0000866291-21-000007 | 10-Q | XBRL Viewer

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Cover Page - shares	9 Months Ended
Cover Page - shares	Dec. 25, 2020	Feb. 01, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 25, 2020
Current Fiscal Year End Date	--12-25
Document Transition Report	false
Entity File Number	001-39675
Entity Registrant Name	ALLEGRO MICROSYSTEMS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-2405937
Entity Address, Address Line One	955 Perimeter Road
Entity Address, City or Town	Manchester,
Entity Address, State or Province	NH
Entity Address, Postal Zip Code	03103
City Area Code	603
Local Phone Number	626-2300
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	ALGM
Security Exchange Name	NASDAQ
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		189,433,744
Entity Central Index Key	0000866291
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Current assets:
Cash and cash equivalents	$ 157,653	$ 214,491
Restricted cash	6,520	5,385
Trade accounts receivable, net of allowances for doubtful accounts of $138 and $288 at December 25, 2020 and March 27, 2020, respectively	67,334	59,457
Trade and other accounts receivable due from related party	20,153	30,851
Accounts receivable - other	1,373	1,796
Inventories	94,021	127,227
Prepaid expenses and other current assets	31,476	9,014
Total current assets	378,530	448,221
Property, plant and equipment, net	214,372	332,330
Deferred income tax assets	23,188	7,217
Goodwill	20,249	1,285
Intangible assets, net	36,420	19,958
Equity investment in related party	26,657	0
Other assets, net	12,482	8,810
Total assets	711,898	817,821
Current liabilities:
Trade accounts payable	20,262	20,762
Amounts due to related party	2,078	4,494
Accrued expenses and other current liabilities	66,779	56,855
Current portion of related party debt	0	25,000
Bank lines-of-credit	0	43,000
Total current liabilities	89,119	150,111
Obligations due under Senior Secured Credit Facilities	25,000	0
Related party notes payable, less current portion	0	17,700
Other long-term liabilities	20,861	15,878
Total liabilities	134,980	183,689
Commitments and contingencies (Note 16)
Stockholders' Equity:
Preferred Stock, $0.01 par value; 20,000,000 shares authorized, no shares issued or outstanding at December 25, 2020 and March 27, 2020	0	0
Common stock	1,894	0
Additional paid-in capital	589,202	458,697
(Accumulated deficit) / retained earnings	(5,094)	194,355
Accumulated other comprehensive loss	(10,171)	(19,976)
Equity attributable to Allegro MicroSystems, Inc.	575,831	633,182
Non-controlling interests	1,087	950
Total stockholders' equity	576,918	634,132
Total liabilities, non-controlling interest and stockholders' equity	711,898	817,821
Common Stock, Class A
Stockholders' Equity:
Common stock	0	100
Common Stock, Class L
Stockholders' Equity:
Common stock	$ 0	$ 6

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Allowances for doubtful accounts	$ 138	$ 288
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	0
Common stock, shares issued (in shares)	189,431,726	0
Common stock, shares outstanding (in shares)	189,431,726	0
Common Stock, Class A
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	0	12,500,000
Common stock, shares issued (in shares)	0	10,000,000
Common stock, shares outstanding (in shares)	0	10,000,000
Common Stock, Class L
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	0	1,000,000
Common stock, shares issued (in shares)	0	622,470
Common stock, shares outstanding (in shares)	0	622,470

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Net sales	$ 164,449	$ 159,802	$ 416,099	$ 475,485
Cost of goods sold	90,024	98,277	224,203	285,967
Gross Profit	74,425	61,525	191,896	189,518
Operating expenses:
Research and development	30,999	25,485	80,509	77,565
Selling, general and administrative	67,650	24,909	118,677	78,030
Total operating expenses	98,649	50,394	199,186	155,595
Operating (loss) income	(24,224)	11,131	(7,290)	33,923
Other (expense) income:
Loss on debt extinguishment	(9,055)	0	(9,055)	0
Interest (expense) income, net	(2,598)	10	(1,935)	(60)
Foreign currency transaction (loss) gain	(145)	(560)	(1,331)	2,800
Income in earnings of equity investment	949	0	1,407	0
Other, net	(510)	(81)	(297)	(1,177)
(Loss) income before income tax (benefit) provision	(35,583)	10,500	(18,501)	35,486
Income tax (benefit) provision	(30,523)	1,542	(27,913)	11,710
Net (loss) income	(5,060)	8,958	9,412	23,776
Net income attributable to non-controlling interests	35	32	103	101
Net (loss) income attributable to Allegro MicroSystems, Inc.	$ (5,095)	$ 8,926	$ 9,309	$ 23,675
Net (loss) income attributable to Allegro MicroSystems, Inc. per share (Note 17):
Basic (in dollars per share)	$ (0.04)	$ 0.89	$ 0.19	$ 2.37
Diluted (in dollars per share)	$ (0.04)	$ 0.89	$ 0.05	$ 2.37
Weighted average shares outstanding:
Basic (in shares)	124,363,078	10,000,000	48,121,026	10,000,000
Diluted (in shares)	124,363,078	10,000,000	171,638,787	10,000,000
Non-Related Party Revenue
Net sales	$ 138,010	$ 143,267	$ 343,529	$ 426,158
Related Party Revenue
Net sales	$ 26,439	$ 16,535	$ 72,570	$ 49,327

Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (5,060)	$ 8,958	$ 9,412	$ 23,776
Foreign currency translation adjustment	3,972	2,886	10,152	1,869
Net actuarial loss amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax	0	0	(313)	0
Comprehensive (loss) income	(1,088)	11,844	19,251	25,645
Comprehensive expense attributable to non-controlling interest	(10)	(23)	(34)	(5)
Comprehensive (loss) income attributable to Allegro MicroSystems, Inc.	$ (1,098)	$ 11,821	$ 19,217	$ 25,640

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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+ Details

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Stock, Class A	Common Stock, Class L	Common Stock	Common Stock Common Stock, Class A	Common Stock Common Stock, Class L	Additional Paid-In Capital	Retained Earnings / Accum. Deficit	Accumulated Other Comprehensive Loss	Non-Controlling Interests
Beginning balance (in shares) at Mar. 29, 2019					10,000,000	607,620
Beginning balance at Mar. 29, 2019	$ 589,789				$ 100	$ 6	$ 447,762	$ 157,385	$ (16,278)	$ 814
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	23,776							23,675		101
Issuance of common stock (in shares)						30,300
Stock-based compensation	1,051						1,051
Foreign currency translation adjustment	1,869								1,864	5
Net actuarial loss and amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax	0
Ending balance (in shares) at Dec. 27, 2019					10,000,000	607,620
Ending balance at Dec. 27, 2019	616,485				$ 100	$ 6	448,813	181,060	(14,414)	920
Beginning balance (in shares) at Sep. 27, 2019					10,000,000	607,620
Beginning balance at Sep. 27, 2019	604,338				$ 100	$ 6	448,510	172,134	(17,277)	865
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	8,958							8,926		32
Stock-based compensation	303						303
Foreign currency translation adjustment	2,886								2,863	23
Net actuarial loss and amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax	0
Ending balance (in shares) at Dec. 27, 2019					10,000,000	607,620
Ending balance at Dec. 27, 2019	$ 616,485				$ 100	$ 6	448,813	181,060	(14,414)	920
Beginning balance (in shares) at Mar. 27, 2020	0	10,000,000	622,470	0	10,000,000	622,470
Beginning balance at Mar. 27, 2020	$ 634,132			$ 0	$ 100	$ 6	458,697	194,355	(19,976)	950
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)						17,203
Ending balance (in shares) at Nov. 01, 2020			638,298
Beginning balance (in shares) at Mar. 27, 2020	0	10,000,000	622,470	0	10,000,000	622,470
Beginning balance at Mar. 27, 2020	$ 634,132			$ 0	$ 100	$ 6	458,697	194,355	(19,976)	950
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,412							9,309		103
Capitalization changes related to organizational structure of affiliates and direct and indirect interests in subsidiaries	(19,165)						(19,165)
Issuance of common stock (in shares)				25,000,000		15,828
Issuance of common stock	321,425			$ 250			321,175
Stock-based compensation	46,901						46,901
Conversion of Class A and Class L common stock into common stock in connection with the IPO (in shares)				166,500,000	(10,000,000)	(636,301)
Conversion of Class A and Class L common stock into common stock in connection with the IPO	0			$ 1,665	$ (100)	$ (6)	(1,559)
Repurchase of Class A and Class L common stock to cover related taxes (in shares)				(2,068,274)		(1,997)
Repurchase of Class A and Class L common stock to cover related taxes	(27,707)			$ (21)			(27,686)
Conversion of LTCIP/TRIP awards into restricted stock units in connection with the IPO	2,081						2,081
Cash dividend paid to holders of Class A common stock	(400,000)						(191,242)	(208,758)
Foreign currency translation adjustment	10,152								10,118	34
Net actuarial loss and amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax	$ (313)								(313)
Ending balance (in shares) at Dec. 25, 2020	189,431,726	0	0	189,431,726	0	0
Ending balance at Dec. 25, 2020	$ 576,918			$ 1,894	$ 0	$ 0	589,202	(5,094)	(10,171)	1,087
Beginning balance (in shares) at Sep. 25, 2020				0	10,000,000	638,298
Beginning balance at Sep. 25, 2020	635,506			$ 0	$ 100	$ 6	439,732	208,759	(14,133)	1,042
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	(5,060)							(5,095)		35
Reclassification of certain class L shares	298						298
Capitalization changes related to organizational structure of affiliates and direct and indirect interests in subsidiaries	527						527
Issuance of common stock (in shares)				25,000,000
Issuance of common stock	321,425			$ 250			321,175
Stock-based compensation	45,876						45,876
Conversion of Class A and Class L common stock into common stock in connection with the IPO (in shares)				166,500,000	(10,000,000)	(636,301)
Conversion of Class A and Class L common stock into common stock in connection with the IPO	0			$ 1,665	$ (100)	$ (6)	(1,559)
Repurchase of Class A and Class L common stock to cover related taxes (in shares)				(2,068,274)		(1,997)
Repurchase of Class A and Class L common stock to cover related taxes	(27,707)			$ (21)			(27,686)
Conversion of LTCIP/TRIP awards into restricted stock units in connection with the IPO	2,081						2,081
Cash dividend paid to holders of Class A common stock	(400,000)						(191,242)	(208,758)
Foreign currency translation adjustment	3,972								3,962	10
Net actuarial loss and amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax	$ 0
Ending balance (in shares) at Dec. 25, 2020	189,431,726	0	0	189,431,726	0	0
Ending balance at Dec. 25, 2020	$ 576,918			$ 1,894	$ 0	$ 0	$ 589,202	$ (5,094)	$ (10,171)	$ 1,087

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 9,412	$ 23,776
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	36,225	47,608
Amortization of deferred financing costs	226	0
Deferred income taxes	(17,526)	(288)
Stock-based compensation	46,901	1,051
Loss on disposal of assets	272	718
Loss on debt extinguishment	9,055	0
Provisions for inventory and bad debt	3,857	3,353
Changes in operating assets and liabilities:
Trade accounts receivable	(5,975)	15,540
Accounts receivable - other	115	657
Inventories	1,118	(341)
Prepaid expenses and other assets	(29,655)	(6,165)
Trade accounts payable	2,411	1,100
Due to/from related parties	8,283	(20,969)
Accrued expenses and other current and long-term liabilities	(1,185)	(17,270)
Net cash provided by operating activities	63,534	48,770
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(25,880)	(34,997)
Acquisition of business, net of cash acquired	(8,500)	0
Proceeds from sales of property, plant and equipment	314	3,936
Contribution of cash balances due to divestiture of subsidiary	(16,335)	0
Net cash used in investing activities	(50,401)	(31,061)
CASH FLOWS FROM FINANCING ACTIVITIES:
Related party note receivable	51,377	30,000
Proceeds from initial public offering, net of underwriting discounts and other offering costs	321,425	0
Payments for taxes related to net share settlement of equity awards	(27,707)	0
Dividends paid	(400,000)	0
Borrowings of senior secured debt, net of deferred financing costs	315,719	0
Repayment of senior secured debt	(300,000)	0
Repayment of unsecured credit facilities	(33,000)	0
Net cash (used in) provided by financing activities	(72,186)	30,000
Effect of exchange rate changes on Cash and cash equivalents and Restricted cash	3,350	(6,452)
Net (decrease) increase in Cash and cash equivalents and Restricted cash	(55,703)	41,257
Cash and cash equivalents and Restricted cash at beginning of period	219,876	103,257
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD:	164,173	144,514
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH:
Cash and cash equivalents at beginning of period	214,491	99,743
Restricted cash at beginning of period	5,385	3,514
Cash and cash equivalents and Restricted cash at beginning of period	219,876	103,257
Cash and cash equivalents at end of period	157,653	139,306
Restricted cash at end of period	6,520	5,208
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD:	164,173	144,514
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for interest	2,559	872
Cash paid for income taxes	7,568	12,937
Noncash transactions:
Changes in Trade accounts payable related to Property, plant and equipment, net	(786)	(2,663)
Loans to cover purchase of common stock under employee stock plan	171	232
Deconsolidation related to PSL Divestiture (Note 1)	$ 0	$ 0

Nature of the Business and Basis of Presentation

9 Months Ended

Dec. 25, 2020

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of the Business and Basis of Presentation

Allegro MicroSystems, Inc., together with its consolidated subsidiaries (“AMI” or the “Company”), is a global leader in designing, developing and manufacturing sensing and power solutions for motion control and energy-efficient systems in automotive and industrial markets. The Company was incorporated under the laws of Delaware on March 30, 2013 under the name of Sanken North America, Inc. (“SKNA”) as a wholly owned subsidiary of Sanken Electric Co., Ltd. (“Sanken”). In October 2017, Sanken sold 28.8% of the common stock of SKNA to One Equity Partners (“OEP”). In April 2018, SKNA filed a certificate of amendment in the state of Delaware to change its name to Allegro MicroSystems, Inc. The Company is headquartered in Manchester, New Hampshire and has a global footprint with 16 locations across four continents.

The accompanying unaudited condensed consolidated financial statements have been prepared by the Company. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The unaudited condensed consolidated financial statements include the Company's accounts and those of its subsidiaries. All intercompany balances have been eliminated in consolidation. These unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Registration Statement on Form S-1 filed with the SEC on February 2, 2021 (the “Registration Statement”). In the opinion of the Company's management, the financial information for the interim periods presented reflects all adjustments necessary for a fair presentation of the Company's financial position, results of operations and cash. The results reported in these unaudited condensed consolidated financial statements are not necessarily indicative of results that may be expected for the entire year.

On November 2, 2020, the Company completed its initial public offering (“IPO”) of 28,750,000 shares of its common stock at an offering price of $14.00 per share, of which 25,000,000 shares were sold by the Company and 3,750,000 shares were sold by selling stockholders, resulting in net proceeds to the Company of approximately, $321,425 after deducting $20,125 of underwriting discounts and $8,450 of offering costs. The Company’s common stock is now listed on the Nasdaq Global Select Market under the ticker symbol “ALGM.”

On March 28, 2020, the Company entered into an agreement to divest a majority of its ownership interest in Polar Semiconductor, Inc. (“PSL”) to Sanken, in order to better align with its fabless, asset-lite scalable manufacturing strategy (the “PSL Divestiture”). In order to affect this in-kind, noncash transaction, Sanken contributed the forgiveness of the fair value of the entire related party notes payable of $42,700 owed by PSL to Sanken and the Company contributed the forgiveness of the fair value of $15,000 out of the $66,377 total debt owed by PSL to the Company, which was previously eliminated in consolidation. The entire net receivable balance of $51,377 plus accrued interest of $762 was repaid on October 14, 2020. Following the divestiture, Sanken held a 70% majority share in PSL with the Company retaining a 30% minority shareholder interest. The investment was recorded for the 30%, totaling $25,250 at the divestiture date. Beginning with reporting periods on and after March 28, 2020, the investment is included on the Company’s balance sheet as an equity investment in a related party, including $949 and $1,407 of income earned during the three- and nine-month periods ended December 25, 2020.

In addition, the difference between the fair value contributed by both parties at the consummation of this transaction and the book value was treated as an adjustment of capitalization changes related to organizational structure of affiliates and direct and indirect interests in subsidiaries within additional paid-in capital of $19,165 at December 25, 2020. This amount includes an estimated tax effect of $1,552 for the nine-month period ended December 25, 2020.

On March 28, 2020, in connection with the divestiture described above, the Company also formally terminated its distribution agreement with Sanken to distribute Sanken’s products and entered into a transitional services agreement with PSL, which contracted with Sanken as its new channel for fulfillment of Sanken product sales in North America and Europe. Sanken will continue to provide distribution support for the Company’s products in Japan. See Note 20, “Related party transactions,” for further discussion.

In accordance with the PSL Divestiture noted above, the following noncash assets and liabilities and related equity impacts attributable to the unaudited statement of cash flows are summarized below:


	March 28, 2020
Cash and cash equivalents	$	(15,332)
Restricted cash	(1,013)
Trade accounts receivable, net of allowances	37
Accounts receivable – other	(308)
Inventories	(32,250)
Prepaid expenses and other current assets	(376)
Property, plant and equipment, net	(115,341)
Related party note receivable	51,377
Equity investment in related party	25,462
Other assets, net	5,609
Trade accounts payable	4,176
Accrued expenses and other current liabilities	7,150
Current portion of related party debt	25,000
Bank lines-of-credit	10,000
Related party notes payable, less current portion	17,700
Other long-term liabilities	(1,247)
Additional paid-in capital	19,165

Impact of the COVID-19 Pandemic

On March 11, 2020, the COVID-19 outbreak was declared a pandemic by the World Health Organization. The pandemic has resulted in governments around the world implementing increasingly stringent measures to help control the spread of the virus, including quarantines, “shelter in place” and “stay at home” orders, travel restrictions, business curtailments, school closures and other measures. In addition, governments and central banks in several parts of the world have enacted fiscal and monetary stimulus measures to counteract the impacts of the COVID-19 pandemic.

The Company continues to monitor the rapidly evolving conditions and circumstances as well as guidance from international and domestic authorities, including public health authorities, and the Company may need to take additional actions based on their recommendations. There is considerable uncertainty regarding the impact on the Company’s business stemming from current measures and potential future measures that could restrict access to the Company’s facilities, limit manufacturing and support operations and place restrictions on the Company’s workforce and suppliers. The measures implemented by various authorities related to the COVID-19 pandemic have caused the Company to change its business practices, including those related to where employees work, the distance between employees in the Company’s facilities, limitations on the in-person meetings between employees and with customers, suppliers, service providers, and stakeholders, as well as restrictions on business travel to domestic and international locations or to attend trade shows, investor conferences and other events.

The full extent to which the ongoing COVID-19 pandemic adversely affects the Company’s financial performance will depend on future developments, many of which are outside of the Company’s control, are highly uncertain and cannot be predicted, including, but not limited to, the duration and spread of the pandemic, its severity, the effectiveness of actions to contain the virus or treat its impact and how quickly and to what extent normal economic and operating conditions can resume. The COVID-19 pandemic could also result in additional governmental restrictions and regulations, which could adversely affect the Company’s business and financial results. In addition, a recession, depression or other sustained adverse market impact resulting from COVID-19 could materially and adversely affect the Company’s business and its access to needed capital and liquidity. Even after the COVID-19 pandemic has lessened or subsided, the Company may continue to experience adverse impacts on its business and financial performance as a result of its global economic impact.

To the extent that the COVID-19 pandemic adversely affects the Company’s business, results of operations, financial condition or liquidity, it also may heighten many of the other risks. For example, if the business impacts of COVID-19 are

prolonged, this could cause the Company to recognize impairments for goodwill and certain long-lived assets including amortizable intangible assets.

The Company has taken actions to mitigate its financial risk given the uncertainty in global markets caused by the COVID-19 pandemic. During the fourth quarter of fiscal year 2020, the Company borrowed $43,000 under its revolving credit facilities. The borrowing was made as part of the Company’s ongoing efforts to preserve financial flexibility in light of the current uncertainty in the global markets and related effects on the Company’s business resulting from the COVID-19 pandemic. In connection with entering into a new revolving credit facility on September 30, 2020, the Company used cash on hand to repay all amounts outstanding under the line of credit and terminated all commitments thereunder.

On March 27, 2020, the President of the United States signed into law the Coronavirus Aid, Relief and Economic Security Act (“the CARES Act”). The CARES Act contains numerous tax provisions including a correction to the applicable depreciation rates available in the original Tax Cuts and Jobs Act (“TCJA”) for Qualified Improvement Property (“QIP”), temporarily establishes a five year carryback period for current net operating losses (“NOL”), and contains a provision for deferred payment of 2020 employer payroll taxes. The Company currently estimates cash tax benefits of the NOL and QIP changes to be $8,963 and $1,680, respectively. Additionally, the Company plans to defer payment of $2,766 of payroll taxes, with $1,383 to be paid back in the third quarter of fiscal year 2022 and the remainder in the third quarter of fiscal year 2023. Additional income tax provisions of the Act are currently being evaluated and not expected to have material impacts.

Financial Periods

The Company’s third quarter three-month period is a 13-week period ending on the last Friday in December. The Company’s 2021 fiscal three- and nine-month periods ended December 25, 2020, and the Company’s 2020 three- and nine-month periods ended December 27, 2019.

Summary of Significant Accounting Policies	9 Months Ended
Summary of Significant Accounting Policies	Dec. 25, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and disclosures of contingencies at the date of the unaudited consolidated financial statements and the reported amounts of net sales and expenses during the reporting period. Such estimates relate to useful lives of fixed and intangible assets, allowances for doubtful accounts and customer returns and sales allowances. Such estimates could also relate to the fair value of acquired assets and liabilities, including goodwill and intangible assets, net realizable value of inventory, accrued liabilities, the valuation of stock-based awards, deferred tax valuation allowances, and other reserves. On an ongoing basis, management evaluates its estimates. Actual results could differ from those estimates, and such differences may be material to the unaudited condensed consolidated financial statements. Deferred Offering Costs The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in stockholder’s equity as a reduction of the additional paid-in capital generated as a result of the offering. As of December 25, 2020 and March 27, 2020, the Company had $0 and $0 of deferred offering costs, respectively. Concentrations of Credit Risk and Significant Customers Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents and accounts receivable. The Company maintains its cash and cash equivalents with financial institutions, which management believes to be of a high credit quality. To manage credit risk related to accounts receivables, the Company evaluates the creditworthiness of its customers and maintains allowances, to the extent necessary, for potential credit losses based upon the aging of its accounts receivable balances and known collection issues. The Company has not experienced any significant credit losses to date. As of December 25, 2020 and March 27, 2020, Sanken accounted for 19.8% and 33.8% of the Company’s outstanding trade accounts receivable, net, respectively, including related party trade accounts receivable. No other customers accounted for 10% or more of outstanding trade accounts receivable, net during those periods. For the three- and nine-month periods ended December 25, 2020, Sanken accounted for 16.1% and 17.4% of total net sales, respectively. No other customers accounted for 10% or more of total net sales for either of the three- and nine-month periods ended December 25, 2020. For the three- and nine-month periods ended December 27, 2019, Sanken accounted for 10.3% and 10.4% of total net sales, respectively. No other customers accounted for 10% or more of total net sales for either of the three- and nine-month periods ended December 27, 2019. During the three-month period ended December 25, 2020 sales from customers located outside of the United States accounted for, in the aggregate, 85.4% of the Company’s total net sales, with Greater China accounting for 28.1%, Japan accounting for 16.0% and South Korea accounting for 10.7%. No other countries accounted for greater than 10% of total net sales for the three-month period ended December 25, 2020. During the nine-month period ended December 25, 2020, sales from customers located outside of the United States, in the aggregate, accounted for 86.1% of the Company’s total net sales, with Greater China accounting for 27.9%, Japan accounting for 17.4% and South Korea accounting for 10.5%. No other countries accounted for greater than 10% of total net sales for the nine-month period ended December 25, 2020. During the three-month period ended December 27, 2019, sales from customers located outside of the United States, in the aggregate, accounted for 82.8% of the Company’s total net sales, with Japan accounting for 28.8% and Greater China accounting for 22.1%. No other countries accounted for greater than 10% of total net sales for the three-month period ended December 27, 2019. During the nine-month period ended December 27, 2019, sales from customers located outside of the United States, in the aggregate, accounted for 81.8% of the Company’s total net sales, with Japan accounting for 27.8% and Greater China accounting for 20.0%. No other countries accounted for greater than 10% of total net sales for the nine-month period ended December 27, 2019. Impact of Recently Issued Accounting Standards The Company qualifies as “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has elected to “opt in” to the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company will adopt the new or revised standard at the time nonpublic companies adopt the new or revised standard and will do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company. The Company may choose to early adopt any new or revised accounting standards whenever such early adoption is permitted for nonpublic companies. In February 2016, the Financial Accounting Standards Board (“FASB”) issued its new lease accounting guidance in ASU No. 2016-02, “Leases (Topic 842)” (“ASU 2016-02” or “the new lease standard”), subsequently amended by ASU 2018-11, Leases (Topic 842): Targeted Improvements. Under the new guidance, lessees will be required to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. Lessees will no longer be provided with a source of off-balance sheet financing. The new lease guidance also simplifies the accounting for sale and leaseback transactions primarily because lessees must recognize lease assets and lease liabilities. The standard is effective for public companies for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years (i.e., January 1, 2019, for a calendar-year entity). Early application is permitted. Entities have the option of using either a modified retrospective approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, or else a transition option (which the Company expects to use) allowing lessees to not apply the new lease standard in comparative periods but instead recognize a cumulative-effect adjustment to retained earnings as of the date of adoption. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. Lessees and lessors may not apply a full retrospective transition approach. In May 2020, FASB issued ASU No. 2020-05 delaying the effective date of the new lease standard for nonpublic companies to fiscal years beginning after December 15, 2021 and interim periods within those fiscal years beginning after December 15, 2022. The Company expects to adopt this guidance during fiscal year 2022 and its assessment of the impact of adopting this standard is underway, including cataloging all leases, performing a preliminary analysis of the amounts of lease liabilities and right-of-use assets to be recorded and reviewing potential changes to the disclosures on leases. Based on this preliminary assessment, the Company does not expect the adoption of this standard to have a significant impact on its consolidated statement of operations. However, the Company expects that the recognition of right-of-use assets and corresponding lease liabilities will have a significant impact on its consolidated balance sheet. In June 2016, the FASB issued ASU No. 2016-13, “Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”), which adds an impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses, which the FASB believes will result in more timely recognition of such losses. The ASU is also intended to reduce the complexity by decreasing the number of credit impairment models that entities use to account for debt instruments. ASU 2016-03, along with its subsequent clarifications, was effective for public companies beginning after December 15, 2019 and is effective for nonpublic companies for fiscal years beginning after December 15, 2021. The Company is evaluating the new guidance and the expected effect on its consolidated financial statements and related disclosures. In November 2019, the FASB issued ASU No. 2019-10 delaying the effective date for all entities. For public entities, this guidance was effective for annual periods beginning after December 15, 2019, including interim periods within those fiscal years. For nonpublic entities, this guidance is effective for annual periods beginning after December 15, 2022, including interim periods within those fiscal years. In August 2018, the FASB issued ASU No. 2018-14, “Compensation—Retirement Benefits—Defined Benefit Plans—General (Topic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans” (“ASU 2018-14”), which modifies the disclosure requirements for defined benefit pension plans and other postretirement plans. ASU 2018-14 should be applied on a retrospective transition basis, and it is effective for public companies beginning after December 15, 2020 and for nonpublic companies beginning after December 15, 2021. The Company is evaluating the new guidance and the expected effect on its consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement” (“ASU 2018-13”), which modifies the disclosure requirements on fair value measurements in Topic 820, Fair Value Measurement, regarding transfers between levels of financial instruments, amounts of unrealized gains and losses included in other comprehensive (loss) income for Level 3 fair value measurements and the information used to determine the fair value of Level 3 fair value measurements. The standard is effective for both public and nonpublic companies, for annual periods beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted. The Company is currently assessing the potential impact that the adoption of ASU 2018-13 will have on its consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 simplifies the accounting for income taxes by removing certain exceptions for intraperiod tax allocations and deferred tax liabilities for equity method investments and adds guidance on whether a step-up in tax basis of goodwill relates to a business combination or a separate transaction. This ASU is effective for fiscal years beginning after December 15, 2020 for public companies and for fiscal years beginning after December 15, 2021 for nonpublic companies, with early adoption permitted. The Company is evaluating the new guidance and the expected effect on its consolidated financial statements and related disclosures. In January 2020, the FASB issued ASU No. 2020-01, “Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)” (“ASU 2020-01”), which addresses accounting for the transition into and out of the equity method and provides clarification of the interaction of rules for equity securities, the equity method of accounting, and forward contracts and purchase options on certain types of securities. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020 for public companies and beginning after December 15, 2021 for nonpublic entities with early adoption permitted. The Company is currently assessing the potential impact that the adoption of ASU 2020-01 will have on its consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting” (“ASU 2020-04”) to provide temporary optional expedients and exceptions to the contract modifications, hedge relationships, and other transactions affected by reference rate reform if certain criteria are met. This ASU, which was effective for all entities upon issuance on March 12, 2020 and may be applied through December 31, 2022, is applicable to all contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or any other reference rate expected to be discontinued. The Company is still assessing the impact that the adoption of ASU 2020-04 will have on its consolidated financial statements.

Acquisition

9 Months Ended

Dec. 25, 2020

Business Combinations [Abstract]

Acquisition

On August 28, 2020, the Company closed on its purchase of Voxtel, Inc. (the “Acquisition”), a privately-held technology company located in Beaverton, Oregon that develops, manufactures and supplies photonic and advanced 3D imaging technologies. The total preliminary purchase price was $35,081, including certain earn-outs that have the potential payout of $15,000. The fair value of these earn-outs at acquisition date was $7,800.

The Acquisition has been accounted for as a business combination and, in accordance with ASC 805, Business Combinations, the Company has recorded the assets acquired and liabilities assumed at their respective fair values as of the date of the Acquisition. The following table summarizes the preliminary purchase price allocation recorded:


Estimated fair value of consideration:
Base purchase price	$	27,281
Contingent Consideration	7,800
Total estimated fair value of consideration	$	35,081
Estimated fair value of assets acquired and liabilities assumed:
Net working capital	$	4,064
Property and equipment	57
Finite-life intangible assets	13,600
Indefinite-life intangible assets	2,400
Deferred tax liability	(3,843)
Goodwill	18,803
Allocated purchase price	$	35,081

The significant intangible assets identified in the preliminary purchase price allocation discussed above include completed technology, in-process research and development, customer relationships and trademarks. Completed technology, customer relationships and trademarks are amortized over their respective useful lives on a straight-line basis. An estimated fair value of $2,400 was assigned to acquired in-process research and development costs with an indefinite life.

Amortization of completed technology is included within cost of revenue, and amortization of customer relationships and trademarks is included within selling, general and administrative expense. To value the completed technology and the in-process research and development assets, the Company utilized the income approach, specifically a discounted cash-flow method known as the multi-period excess earnings method. Customer relationships represent the underlying relationships with certain customers to provide ongoing services for products sold. The Company utilized the income approach, specifically the distribution method, a subset of the excess-earnings method to value the customer relationships and trademarks.

The following table presents the estimated fair values and useful lives of the identifiable finite-life intangible assets acquired:


	Useful Life	Fair value
Completed technology	12 years	$	13,100
Customer relationships	6 years	300
Trademarks	5 years	200
		$	13,600

Goodwill was recognized for the excess purchase price over the fair value of the net assets acquired. The goodwill reflects the value of the synergies the Company expects to realize and the assembled workforce. Goodwill from the Acquisition is included within the Company’s one reporting unit and is included in the Company’s enterprise-level annual review for impairment. Goodwill resulting from the Acquisition is not deductible for tax purposes.

The purchase price has been allocated to the tangible and intangible assets acquired and liabilities assumed based upon the respective estimates of fair value as of the date of the Acquisition, which remains preliminary, and using assumptions that the Company’s management believes are reasonable given the information then available. The final allocation of the purchase price may differ materially from the information presented in these condensed consolidated financial statements. Any

changes to the preliminary estimates of the fair value of the assets acquired and liabilities assumed will be recorded as adjustments to those assets and liabilities and residual amounts will be allocated to goodwill.

The revenues and loss before income taxes from the Acquisition were immaterial to the Company’s consolidated results for the three- and nine-month periods ended December 25, 2020. The Company has not presented pro forma results of operations for the Acquisition because it is not material to the Company's consolidated results of operations, financial position, or cash flows.

Revenue from Contract with Customers

9 Months Ended

Dec. 25, 2020

Revenue from Contract with Customer [Abstract]

Revenue from Contracts with Customers

The Company generates revenue from the sale of magnetic sensor integrated circuits (“ICs”), application-specific analog power semiconductors, wafer foundry products and from the sale of Sanken-related products. The following tables summarize net sales disaggregated by core end market and application, by product and by geography for the three- and nine-month periods ended December 25, 2020 and December 27, 2019. The categorization of net sales by core end market and application is determined using various characteristics of the product and the application into which the Company’s product will be incorporated. The categorization of net sales by geography is determined based on the location the products are being shipped to.

Net sales by core end market and application:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Core end market:
Automotive	$	113,902	$	99,074	$	279,759	$	289,681
Industrial	23,654		21,358		65,710		56,095
Other	26,893		15,070		70,630		53,399
Other applications:
Wafer foundry products	—		16,634		—		49,622
Distribution of Sanken products	—		7,666		—		26,688
Total net sales	$	164,449	$	159,802	$	416,099	$	475,485

Net sales by product:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Power integrated circuits (“PIC”)	$	54,406	$	43,665	$	146,276	$	123,900
Magnetic sensors (“MS”)	109,457		91,837		268,956		275,275
Photonics	586		—		867		—
Wafer foundry products	—		16,634		—		49,622
Distribution of Sanken products	—		7,666		—		26,688
Total net sales	$	164,449	$	159,802	$	416,099	$	475,485

Net sales by geography:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Americas:
United States	$	23,934	$	27,498	$	57,892	$	86,746
Other Americas	5,620		4,722		10,797		15,930
EMEA:
Europe	28,239		24,341		70,459		76,622
Asia:
Japan	26,439		46,010		72,570		131,950
Greater China	46,172		35,284		116,178		95,244
South Korea	17,606		14,119		43,733		41,413
Other Asia	16,439		7,828		44,470		27,580
Total net sales	$	164,449	$	159,802	$	416,099	$	475,485

The Company recognizes sales net of returns, credits issued, price protection adjustments and stock rotation rights. At December 25, 2020 and March 27, 2020, these adjustments were $16,574 and $17,473, respectively, and were netted against trade accounts receivable in the unaudited consolidated balance sheets. These amounts represent activity of credits of $899 and $815 for the nine-month periods ended December 25, 2020 and December 27, 2019, respectively.

Unsatisfied performance obligations primarily represent contracts for products with future delivery dates. The Company elected to not disclose the amount of unsatisfied performance obligations as these contracts have original expected durations of less than one year.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Fair Value Measurements

9 Months Ended

Dec. 25, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

The following tables present information about the Company’s financial assets and liabilities as of December 25, 2020 and March 27, 2020 measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values:


	Fair Value Measurement at December 25, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market fund deposits	$	16,320	$	—	$	—	$	16,320
Restricted cash:
Money market fund deposits	6,520		—		—		6,520
Total assets	$	22,840	$	—	$	—	$	22,840
Liabilities:
Other long-term liabilities:
Contingent consideration	$	—	$	—	$	7,800	$	7,800
Total liabilities	$	—	$	—	$	7,800	$	7,800


	Fair Value Measurement at March 27, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market fund deposits	$	46,337	$	—	$	—	$	46,337
Restricted cash:
Money market fund deposits	5,385		—		—		5,385
Total assets	$	51,722	$	—	$	—	$	51,722

The following table shows the change in fair value of Level 3 contingent consideration in connection with the Acquisition for the nine-month period ended December 25, 2020:


	Level 3 Contingent Consideration
Balance at March 27, 2020	$	—
Additions during the year	7,800

Balance at December 25, 2020	$	7,800

Assets and liabilities measured at fair value on a recurring basis also consist of marketable securities, unit investment trust fund, loans, bonds, stock and other investments which are the Company’s defined benefit plan assets. Fair value information for those assets and liabilities, including their classification in the fair value hierarchy, is included in Note 15, “Retirement Plans.”

During the nine-month periods ended December 25, 2020 and December 27, 2019, there were no transfers among Level 1, Level 2 and Level 3.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Trade Accounts Receivable, net

9 Months Ended

Dec. 25, 2020

Receivables [Abstract]

Trade Accounts Receivable, net

Trade accounts receivable, net (including related party trade accounts receivable) consisted of the following:


	December 25, 2020		March 27, 2020
Trade accounts receivable	$	103,687	$	107,223
Less:
Allowance for doubtful accounts	(138)		(288)
Returns and sales allowances	(16,437)		(17,185)
Related party trade accounts receivable	(19,778)		(30,293)
Total	$	67,334	$	59,457

Changes in the Company’s allowance for doubtful accounts and returns and sales allowances were as follows:


Description	Allowance for Doubtful Accounts		Returns and Sales Allowances		Total
Balance at March 27, 2020	$	288	$	17,185	$	17,473
Charged to costs and expenses or revenue	(150)		103,660		103,510
Write-offs, net of recoveries	—		(104,408)		(104,408)
Balance at December 25, 2020	$	138	$	16,437	$	16,575


Description	Allowance for Doubtful Accounts		Returns and Sales Allowances		Total
Balance at March 29, 2019	$	412	$	17,607	$	18,019
Charged to costs and expenses or revenue	(175)		91,690		91,515
Write-offs, net of recoveries	—		(92,330)		(92,330)
Balance at December 27, 2019	$	237	$	16,967	$	17,204

Inventories

9 Months Ended

Dec. 25, 2020

Inventory Disclosure [Abstract]

Inventories

Inventories include material, labor and overhead and consisted of the following:


	December 25, 2020		March 27, 2020
Raw materials and supplies	$	8,689	$	12,411
Work in process	57,477		87,606
Finished goods	24,451		24,659
Finished goods – consigned	3,404		2,551
Total	$	94,021	$	127,227

In connection with the Acquisition, the Company acquired inventory with a stepped-up basis of $3,120, for which $1,245 was on-hand at December 25, 2020. The Company recorded inventory provisions totaling $885 and $2,958 for the three- and nine-month periods ended December 25, 2020, respectively, and $1,008 and $2,538 for the three- and nine-month periods ended December 27, 2019, respectively.

Property, Plant and Equipment, net

9 Months Ended

Dec. 25, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment, net

Property, plant and equipment, net is stated at cost, and consisted of the following:


	December 25, 2020		March 27, 2020
Land	$	23,829	$	27,898
Buildings, building improvements and leasehold improvements	91,535		150,402
Machinery and equipment	488,796		694,215
Office equipment	6,643		7,517
Construction in progress	10,956		27,919
Total	621,759		907,951
Less accumulated depreciation	(407,387)		(575,621)
Total	$	214,372	$	332,330

Total depreciation expense amounted to $11,255 and $33,861 in the three- and nine-month periods ended December 25, 2020, respectively, and $15,677 and $46,247 in the three- and nine-month periods ended December 27, 2019, respectively.

Long-lived assets include property, plant and equipment and related deposits on such assets, and capitalized tooling costs. The geographic locations of the Company's long-lived assets, net, based on physical location of the assets, as of December 25, 2020 and March 27, 2020 are as follows:


	December 25, 2020		March 27, 2020
United States	$	35,894	$	152,536
Philippines	136,284		106,618
Thailand	34,226		62,380
Other	9,306		12,112
Total	$	215,710	$	333,646

Amortization of prepaid tooling costs amounted to $18 and $54 for the three- and nine-month periods ended December 25, 2020, respectively, and $32 and $94 in the three- and nine-month periods ended December 27, 2019, respectively.

Goodwill and Intangible Assets

9 Months Ended

Dec. 25, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

The table below summarizes the changes in the carrying amount of goodwill as follows:


	Total
Balance at March 27, 2020	$	1,285
Goodwill arising from Acquisition	18,803
Currency translation	161
Balance at December 25, 2020	$	20,249

Intangible assets, net is as follows:


	December 25, 2020
Description	Gross		Accumulated Amortization		Net Carrying Amount		Weighted- Average Lives
Patents	$	31,852	$	11,661	$	20,191	10 years
Customer relationships	6,193		5,823		370		9 years
Process technology	17,150		2,028		15,122		12 years
Trademarks	810		73		737		5 years
Other	32		32		—
Total	$	56,037	$	19,617	$	36,420


	March 27, 2020
Description	Gross		Accumulated Amortization		Net Carrying Amount		Weighted- Average Lives
Patents	$	29,115	$	9,834	$	19,281	10 years
Customer relationships	5,462		5,335		127		9 years
Process technology	1,650		1,650		—
Trademarks	608		58		550
Other	32		32		—
Total	$	36,867	$	16,909	$	19,958

As summarized in Note 3, “Acquisition,” the Company completed its acquisition of Voxtel, Inc. during the nine-month period ended December 25, 2020. The Company paid an amount of $35,081 to acquire Voxtel, which represents its fair value on that date. Any excess of the Acquisition consideration over the fair value of the assets acquired and liabilities assumed was allocated to goodwill, which amounted to $18,803. As a result of the Acquisition, the Company recorded finite-life intangible assets of $13,600, the types and lives of which are detailed in the above-referenced financial note. In addition, as a result of the Acquisition, the Company recorded indefinite-life intangible assets of $2,400.

Intangible assets amortization expense was $926 and $2,310 for the three- and nine-month periods ended December 25, 2020, respectively, and $422 and $1,267 for the three- and nine-month periods ended December 27, 2019, respectively. The majority of the Company’s intangible assets are related to patents as noted above. The Company capitalizes external legal costs incurred in the defense of its patents when it believes that a significant, discernible increase in value will result from the defense and a successful outcome of the legal action is probable. When the Company capitalizes patent defense costs, it amortizes these costs over the remaining estimated useful life of the patent, which is generally 10 years. There were no such costs capitalized during either of the first nine months of fiscal years 2021 or 2020.

As of December 25, 2020, annual amortization expense of intangible assets for the next five fiscal years is expected to be as follows:


Remainder of 2021	$	850
2022	3,293
2023	3,139
2024	3,003
2025	2,709
Thereafter	23,426
Total	$	36,420

Other Assets, net

9 Months Ended

Dec. 25, 2020

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Other Assets, net

The composition of other assets, net is as follows:


	December 25, 2020		March 27, 2020
VAT receivables long-term, net	$	6,662	$	3,039
Deposits	2,414		2,399
Prepaid contracts long-term	1,478		1,282

Other	1,928		2,090
Total	$	12,482	$	8,810

Accrued Expenses and Other Current Liabilities

9 Months Ended

Dec. 25, 2020

Payables and Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

The composition of accrued expenses and other current liabilities is as follows:


	December 25, 2020		March 27, 2020
Accrued management incentive (LTCIP)	$	94	$	11,488
Accrued management incentive (non-LTCIP)	14,143		6,273
Accrued salaries and wages	18,603		12,069
Base acquisition purchase price due	17,244		—
Accrued vacation	5,534		7,146
Accrued severance	2,643		6,065
Accrued professional fees	1,057		4,036
Accrued income taxes	1,803		3,408
Accrued utilities	628		1,114
Other current liabilities	5,030		5,256
Total	$	66,779	$	56,855

Management Long-Term Incentive Plan

9 Months Ended

Dec. 25, 2020

Management Long-Term Incentive Plan

Management Long-Term Cash Incentive Plan

On August 28, 2015, the Company’s Board of Directors approved a Long-Term Cash Incentive Plan (“LTCIP”) for certain employees. Under the LTCIP, employees receive cash payments upon achievement of certain performance metrics determined based on a three-year rolling performance period. The Company had executed individual agreements with employees to pay certain incentives upon achievement of the plan conditions at the end of each three-year performance period.

In connection with its IPO, the Company offered certain employees (excluding its named executive officers) who were eligible to receive cash bonuses under the Company’s LTCIP and/or Talent Retention Incentive Program (as amended, the “TRIP”) the opportunity to elect to receive restricted stock units (“RSUs”) under its 2020 Omnibus Incentive Compensation Plan in lieu of cash payouts under the LTCIP and/or TRIP, through the LTCIP/TRIP Award RSU Conversion Program (the “RSU Conversion Program”). The expense related to the LTCIP and TRIP awards elected to be exchanged in the RSU Conversion Program amounted to $607 and $421, respectively. The number of RSUs granted to employees that elected to participate in the RSU Conversion Program is determined as a percentage of the employee’s target bonus under the LTCIP or

TRIP, and amounted to 602,490 and 348,911 RSUs on behalf of the LTCIP and TRIP conversion, respectively, at a grant date fair value of $14.00. If an employee elected not to participate in the RSU Conversion Program, the LTCIP or TRIP award will continue under its existing terms and conditions.

The accrual activity, payments, removal due to divestitures and balances related to the LTCIP are as follows:


Description	Current Liabilities		Long-Term Liabilities
Balance at March 27, 2020	$	11,488	$	2,439
Reclassification	1,004		(1,004)
Payments	(11,096)		—
RSU conversion	(640)		—
Removal due to divestiture	(378)		(398)
Accruals	(284)		(843)
Balance at December 25, 2020	$	94	$	194

The current and long-term portion of the liabilities associated with the LTCIP is included within accrued expenses and other current liabilities and other long-term liabilities in the Company’s unaudited consolidated balance sheets, respectively.

Debt and Other Borrowings

9 Months Ended

Dec. 25, 2020

Debt Disclosure [Abstract]

Debt and Other Borrowings

Components of Debt

The following is a summary of obligations under the Company’s Senior Secured Credit Facilities and other borrowings at December 25, 2020 and March 27, 2020:


	December 25, 2020		March 27, 2020
Senior Secured Term Loan	$	25,000	$	—

Unsecured Revolving Credit Facilities	—		43,000
Total Debt	25,000		43,000
Less debt payable within one year	—		43,000
Debt payable after one year	$	25,000	$	—

The principal maturities of debt obligations outstanding were as follows at December 25, 2020:


Remainder of 2021	$	—
2022	—
2023	—
2024	—
2025	—
Thereafter	25,000
Total	$	25,000

Senior Secured Credit Facilities:

On September 30, 2020, the Company entered into a term loan credit agreement with Credit Suisse AG, Cayman Islands Branch, as administrative agent and collateral agent, and the other agents, arrangers and lenders party thereto, providing for a $325,000 senior secured term loan facility due in 2027 (the “Term Loan Facility”). On September 30, 2020, the Company also entered into a revolving facility credit agreement with Mizuho Bank, Ltd., as administrative agent and collateral agent, and the other agents, arrangers and lenders party thereto, providing for a $50,000 senior secured revolving credit facility expiring in 2023 (the “Revolving Credit Facility” and, together with the Term Loan Facility, the “Senior Secured Credit Facilities”). The Revolving Credit Facility is secured by a lien on the same collateral and on the same basis as the Term Loan Facility. Interest on the Term Loan Facility is calculated at LIBOR plus 3.75% to 4.00% based on the

Company’s net leverage ratio, and LIBOR is subject to a 0.5% floor. The Company’s outstanding borrowings bore an interest rate of 4.5% at December 25, 2020. The Company has not borrowed on the Revolving Credit Facility at December 25, 2020.

In connection with entering into the Revolving Credit Facility, the Company used cash on hand to repay all prior amounts outstanding under AML’s $25,000 and $8,000 line of credit agreements and terminated all commitments thereunder.

Included in the Term Loan Facility were deferred financing costs of $9,374, which the Company has deducted from the carrying amount presented on its unaudited consolidated balance sheet and amortized into interest expense or recognized as loss on debt extinguishment. Included in the Revolving Credit Facility were deferred financing costs of $300, which the Company classified the related short-term and long-term portions within “Prepaid expenses and other current assets” and “Other assets” on its unaudited consolidated balance sheet and is amortizing those costs over the term of the facility. The unamortized portion of the deferred financing costs associated with the Revolving Credit Facility was $254 at December 25, 2020.

On November 25, 2020, the Company repaid $300,000 of the outstanding $325,000 Term Loan Facility using proceeds from the Company’s recently completed IPO. The repayment was accounted for as a debt extinguishment in accordance with provisions of ASC Topic 470-50, Debt Modifications and Extinguishments. The Company recognized a loss on debt extinguishment of $9,055, which was included within “Other (expense) income” in the unaudited consolidated statement of operations at December 25, 2020. The loss on debt extinguishment consisted of the unamortized balances of previously deferred financing costs which the Company wrote off.

Unsecured Revolving Credit Facilities:

On January 22, 2019, the Company, through its subsidiaries, entered into a revolving line of credit agreement, with a financial institution, that provided for a maximum borrowing capacity of $25,000. The revolving line of credit bore interest at LIBOR on the day of the advance plus a 0.4% spread payable upon maturity of the draws, and expired on January 22, 2021. During fiscal year 2020, the Company borrowed $25,000 under the revolving line of credit. As of March 27, 2020, the Company had a $25,000 outstanding balance under the revolving line of credit agreement with an original repayment date of June 19, 2020 at an interest rate of 1.7%. In the first quarter of fiscal 2021, repayment of the $25,000 borrowings under the revolving line of credit was extended to December 18, 2020. The revolving line of credit was secured, for a one-year period, by a non-refundable fee of $25 that was paid to the financial institution. In connection with entering into a new revolving credit facility on September 30, 2020, the Company used cash on hand to repay all amounts outstanding under the line of credit and terminated all commitments thereunder.

On March 27, 2006, the Company, through its PSL subsidiary, entered into a revolving line of credit agreement, with a financial institution, that provides for a maximum borrowing capacity of $10,000. The revolving line of credit bore interest at LIBOR on the day of the advance plus 1.0% spread payable upon maturity of the draws and was guaranteed by Sanken. Under the terms of the revolving line of credit agreement, the principal was due at various times during fiscal year 2021. During fiscal year 2020, the Company borrowed $10,000 under the revolving line of credit. As of March 27, 2020, the Company had a $10,000 outstanding balance under the revolving line of credit agreement maturing on September 16, 2020, at an interest rate of 2.5%. On March 28, 2020, in conjunction with the divestiture of PSL, the debt was deconsolidated.

On December 5, 2001, the Company, through its subsidiaries, entered into a line of credit agreement with a financial institution that provided for a maximum borrowing capacity of $8,000. On March 18, 2020, the Company borrowed $8,000 under the line of credit. As of March 27, 2020, the Company had an $8,000 outstanding balance under the line of credit agreement maturing on June 18, 2020 at an interest rate of 1.9%. In the first quarter of fiscal 2021, repayment of the $8,000 borrowings under the line of credit was extended to December 21, 2020. In connection with entering into a new revolving credit facility on September 30, 2020, the Company used cash on hand to repay all amounts outstanding under the line of credit and terminated all commitments thereunder.

On November 26, 2019, the Company, through its subsidiaries, entered into a line of credit agreement with a financial institution that provides for a maximum borrowing capacity of 60,000 Philippine pesos (approximately $1,247 at December 25, 2020) at the bank’s prevailing interest rate. The line of credit was due to expire on August 31, 2021. There were no borrowings outstanding under this line of credit as of December 25, 2020 and March 27, 2020.

On November 20, 2019, the Company, through its subsidiaries, entered into a line of credit agreement with a financial institution that provides for a maximum capacity of 75,000 Philippine pesos (approximately $1,559 at December 25, 2020) at the bank’s prevailing interest rate. The line of credit was due to expire on June 30, 2021. There were no borrowings outstanding under this line of credit as of December 25, 2020 and March 27, 2020.

Given the continued uncertainty surrounding COVID-19, during the month of March 2020, the Company executed a $43,000 drawdown of the majority of its remaining available lines-of-credit under its existing agreements, as noted above. The Company took this action as a precautionary measure to increase its cash position and help maintain financial flexibility. The proceeds from the drawdown were used for working capital, general corporate or other purposes during the COVID-19 pandemic into fiscal year 2021.

Other Long-Term Liabilities

9 Months Ended

Dec. 25, 2020

Other Liabilities Disclosure [Abstract]

Other Long-Term Liabilities

The composition of other long-term liabilities is as follows:


	December 25, 2020		March 27, 2020
Accrued management incentive (LTCIP)	$	194	$	2,439
Accrued management incentive (non-LTCIP)	318		2,304
Accrued retirement	9,516		8,005
Accrued contingent consideration	7,800		—
Provision for uncertain tax positions (net)	2,758		2,855
Other	275		275
Total	$	20,861	$	15,878

Retirement Plans

9 Months Ended

Dec. 25, 2020

Retirement Benefits [Abstract]

Retirement Plans

The Company recognizes the funded status (i.e., the difference between the fair value of plan assets and the benefit obligations) of its defined benefit pension plans in its unaudited consolidated balance sheets with a corresponding adjustment to accumulated other comprehensive income (“AOCI”), net of tax. These amounts will continue to be recognized as a component of future net periodic benefit costs consistent with the Company’s past practice. Further, actuarial gains and losses and prior service costs that arise in future periods and are not recognized as net periodic benefit costs in the same periods will be recognized as a component of other comprehensive income. Those amounts will also be recognized as a component of future net periodic benefit costs consistent with the Company’s past practice. The Company uses a measurement date for its defined benefit pension plans and other postretirement benefit plans that is equivalent to its fiscal year-end.

Plan Descriptions

Non-U.S. Defined Benefit Plan

The Company, through its wholly owned subsidiary, Allegro MicroSystems Philippines, Inc. (“AMPI”), has a defined benefit pension plan, which is a noncontributory plan that covers substantially all employees of the respective subsidiary. The plan’s assets are invested in common trust funds, bonds and other debt instruments and stocks.

Effect on the unaudited statements of operations

Expense related to the non-U.S. defined benefit plan was as follows:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Service cost	$	296	$	242	$	843	$	717
Interest cost	166		169		474		503
Expected return on plan assets	(79)		(83)		(231)		(247)

Amortization of net transition asset	—		(4)		—		(10)
Amortization of prior service cost	2		2		6		6
Actuarial loss	47		24		126		72
Net periodic pension expense	$	432	$	350	$	1,218	$	1,041

Information on Plan Assets

The table below sets forth the fair value of the entity’s plan assets as of December 25, 2020 and March 27, 2020, using the same three-level hierarchy of fair value inputs described in the significant accounting policies included in the audited consolidated financial statements as of March 27, 2020 and for the year then ended, which are included in the previously filed Registration Statement.


	Fair Value at December 25, 2020		Level 1		Level 2		Level 3
Assets of non-U.S. defined benefit plan:
Government securities	$	1,826	$	1,826	$	—	$	—
Unit investment trust fund	1,155		—		1,155		—
Loans	562		—		—		562
Bonds	1,193		—		1,193		—
Stocks and other investments	2,353		1,205		1		1,147
Total	$	7,089	$	3,031	$	2,349	$	1,709


	Fair Value at March 27, 2020		Level 1		Level 2		Level 3
Assets of non-U.S. defined benefit plan:
Government securities	$	1,260	$	1,260	$	—	$	—
Unit investment trust fund	897		—		897		—
Loans	756		—		—		756
Bonds	1,094		—		1,094		—
Stocks and other investments	1,572		1,207		1		364
Total	$	5,579	$	2,467	$	1,992	$	1,120

The following table shows the change in fair value of Level 3 plan assets for the nine-month period ended December 25, 2020:


	Level 3 Non-U.S. Defined Plan Assets
	Loans		Stocks
Balance at March 27, 2020	$	756	$	364
Additions during the year	207		—
Redemptions during the year	(440)		—
Revaluation of equity securities	—		753
Change in foreign currency exchange rates	39		30
Balance at December 25, 2020	$	562	$	1,147

The investments in the Company’s major benefit plans largely consist of low-cost, broad-market index funds to mitigate risks of concentration within the market sectors. In recent years, the Company’s investment policy has shifted toward a closer matching of the interest-rate sensitivity of the plan assets and liabilities. The appropriate mix of equity and bond investments is determined primarily through the use of detailed asset-liability modeling studies that look to balance the impact of changes in the discount rate against the need to provide asset growth to cover future service cost. The Company, through its wholly owned subsidiary, Allegro MicroSystems, LLC’s (“AML”), non-U.S. defined benefit plan, has added a greater proportion of fixed income securities with return characteristics that are more closely aligned with changes in liabilities caused by discount rate volatility. There are no significant restrictions on the amount or nature of the investments that may be acquired or held by the plans.

During the three- and nine-month periods ended December 25, 2020, the Company contributed approximately $249 and $736 to its non-U.S. pension plan, respectively, and during the three- and nine-month periods ended December 27, 2019 the Company contributed approximately $235 and $698 to its non-U.S. pension plan, respectively. The Company expects to contribute approximately $943 to its non-U.S. pension plan in fiscal year 2021.

Other Defined Benefit Plan

In December 1993, the Company commenced with a rollover pension promise agreement (“Pension Promise”) to offer a then European employee an insured annuity upon their retirement at age 65. The employee was the only eligible participant of the Pension Promise. The impact associated with the expense and related other income with the Pension Promise was insignificant in fiscal years 2020 and 2019, respectively. The total values of the Pension Promise in the amounts of 827 and 866 British Pounds Sterling at December 25, 2020 and March 27, 2020, respectively (approximately $1,112 and $975 at December 25, 2020 and March 27, 2020, respectively), were classified with other in other assets, net and accrued retirement in other long-term liabilities in the Company’s unaudited consolidated balance sheets.

Defined Contribution Plan

Eligible AML U.S. employees may contribute up to 50% of their pretax compensation to a defined contribution plan, subject to certain limitations, and AML may match, at its discretion, 100% of the participants’ pretax contributions, up to a maximum of 5% of their eligible compensation. Matching contributions by AML totaled approximately $1,112 and $3,181 for the three- and nine-month periods ended December 25, 2020, respectively, and approximately $833 and $2,840 for the three- and nine-month periods ended December 27, 2019, respectively.

The Company, through its AML subsidiary, Allegro MicroSystems Europe, Ltd. (“Allegro Europe”), also has a defined contribution plan (the “AME Plan”) covering substantially all employees of Allegro Europe. Contributions to the AME Plan by the Company totaled approximately $207 and $592 for the three- and nine-month periods ended December 25, 2020, respectively, and approximately $201 and $560 for the three- and nine-month periods ended December 27, 2019, respectively.

The Company has a 401(k) plan that covers all employees meeting certain service and age requirements. Employees are eligible to participate in the plan upon hire when the service and age requirements are met. Employees may contribute up to 35% of their compensation, subject to the maximum contribution allowed by the Internal Revenue Service. All employees are 100% vested in their contributions at the time of plan entry. As of January 1, 2008, and until January 1, 2015, the Company’s former wholly owned subsidiary, PSL, adopted and used a Safe Harbor provision, whereby PSL contributed 3% of compensation each pay period for all eligible employees meeting the Safe Harbor criteria. As of January 1, 2015, PSL may match, at its discretion, 100% of the employee’s contribution, up to a maximum of 5% of their eligible compensation. PSL’s matching contributions in the three- and nine-month periods ended December 27, 2019 was $376 and $1,310, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section S99
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=21916913&loc=d3e273930-122802

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (o)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (p)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 715
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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-Section 50
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-Subparagraph (r)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

Commitment and Contingencies	9 Months Ended
Commitment and Contingencies	Dec. 25, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Leases The Company, through its subsidiaries, leases certain real estate property and equipment under operating lease agreements that expire at various dates between one and seven years. The leases generally require the Company to pay for utilities, insurance, taxes and maintenance. Some leases contain escalation clauses, renewal options and purchase options. There have been no material changes to these lease commitments since March 27, 2020. Insurance The Company, through its subsidiaries, utilizes self-insured employee health programs for employees in the United States. The Company records estimated liabilities for its self-insured health programs based on information provided by the third-party plan administrators, historical claims experience and expected costs of claims incurred but not reported. The Company monitors its estimated liabilities on a quarterly basis. As facts change, it may become necessary to make adjustments that could be material to the Company’s unaudited consolidated financial position and results of operations. Legal proceedings The Company is subject to various legal proceedings and claims, the outcomes of which are subject to significant uncertainty. The Company records an accrual for legal contingencies when it is determined that it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. In making such determinations, the Company evaluates, among other things, the degree of probability of an unfavorable outcome and, when it is probable that a liability has been incurred, and its ability to make a reasonable estimate of the loss. If the occurrence of liability is probable, the Company will disclose the nature of the contingency, and if estimable, will provide the likely amount of such loss or range of loss. Furthermore, the Company does not believe there are any matters that could have a material adverse effect on financial position, results of operations or cash flows. Indemnification From time to time, the Company has agreed to indemnify and hold harmless certain customers for potential allegations of infringement of intellectual property rights and patents arising from the use of its products. To date, the Company has not incurred any costs in connection with such indemnification arrangements; therefore, there was no accrual of such amounts at December 25, 2020 or March 27, 2020. Environmental Matters The Company establishes accrued liabilities for environmental matters when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated. If the contingency is resolved for an amount greater or less than the accrual, or the Company’s share of the contingency increases or decreases or other assumptions relevant to the development of the estimate were to change, the Company would recognize an additional expense or benefit in the unaudited consolidated statements of operations during the period such determination was made. No environmental accruals were established at December 25, 2020 or March 27, 2020.

Net (Loss) Income per Share

9 Months Ended

Dec. 25, 2020

Earnings Per Share [Abstract]

Net (Loss) Income per Share

In connection with completion of the Company’s IPO on November 2, 2020 and immediately following the pricing of the IPO, all outstanding shares of Class A common stock and Class L common stock were automatically converted into an aggregate of 166,500,000 shares of common stock (the “Common Stock Conversion”). Outstanding shares of Class A and Class L common stock were converted to common stock in the Common Stock Conversion at conversion rates of approximately 15.822 and 13.010 shares of common stock to each share of Class A and Class L common stock, respectively. As part of the Common Stock Conversion, 2,066,508 and 1,766 shares of common stock were returned to the Company for tax payments made on behalf of holders of Class A common stock and Class L common stock, respectively, in withhold to cover tax transactions.

Prior to the Company’s IPO, shares of Class A common stock were entitled to a priority dividend of 8%. After Class A shareholders received an annualized return on capital of 8%, distributions of the remaining value were split between Class A and Class L shareholders based on the achievement of certain return targets. In determining income to the Class A stockholders for computing basic and diluted earnings per share for the three- and nine-month periods ended December 27, 2019, the Company did not allocate income to the shares of Class L common stock in accordance with ASC 260, because such classes of shares would not have shared in the distribution had all of the income for the periods been distributed. Accordingly, earnings per share calculations were provided only for the Class A shares with a weighted average of 10,000,000 shares for the three- and nine-month periods ended December 27, 2019.

The following table sets forth the basic and diluted net (loss) income attributable to Allegro MicroSystems, Inc. per share. The number of shares of common stock reflected in the calculation is the total shares of common stock (vested and unvested) held on the IPO date, after the Common Stock Conversion.


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Net (loss) income attributable to Allegro MicroSystems, Inc.	$	(5,095)	$	8,926	$	9,309	$	23,675
Net (loss) income attributable to common stockholders	(5,060)		8,958		9,412		23,776
Basic weighted average shares of common stock	124,363,078		10,000,000		48,121,026		10,000,000
Dilutive effect of common stock equivalents	—		—		123,517,761		—
Diluted weighted average shares of common stock	124,363,078		10,000,000		171,638,787		10,000,000
Basic net (loss) income attributable to Allegro MicroSystems, Inc. per share	$	(0.04)	$	0.89	$	0.19	$	2.37
Basic net (loss) income attributable to common stockholders per share	$	(0.04)	$	0.90	$	0.20	$	2.38
Diluted net (loss) income attributable to Allegro MicroSystems, Inc. per share	$	(0.04)	$	0.89	$	0.05	$	2.37
Diluted net (loss) income attributable to common stockholders per share	$	(0.04)	$	0.90	$	0.05	$	2.38

The computed net loss for the three-month period ended December 25, 2020 does not assume conversion of securities that would have an antidilutive effect on loss per share. As the Company was in a net loss position for the three-month period ended December 25, 2020, all common stock equivalents in this period were antidilutive. There were no such convertible securities to consider for the three- and nine-month periods ended December 27, 2019.

The following represents issuable weighted average share information for the respective periods:


	Three-Month Period Ended		Nine-Month Period Ended
	December 25, 2020	December 27, 2019	December 25, 2020	December 27, 2019
Unvested restricted stock units (“RSUs”)	377,767	—	125,922	—
Unvested performance stock units (“PSUs”)	422,768	—	140,923	—
Shares related to Common Stock Conversion	56,752,747	—	123,250,916	—
Total	57,553,282	—	123,517,761	—

As the Company was in a net loss position for the three-month period ended December 25, 2020, common stock equivalents of 57,553,282 were antidilutive.

Common Stock and Stock-Based Compensation

9 Months Ended

Dec. 25, 2020

Share-based Payment Arrangement [Abstract]

Common Stock and Stock-Based Compensation

On November 2, 2020, the Company completed its IPO of 28,750,000 shares of its common stock at an offering price of $14.00 per share, of which 25,000,000 shares were sold by the Company and 3,750,000 shares were sold by selling stockholders, resulting in net proceeds to the Company of approximately $321,425, after deducting $20,125 of underwriting discounts and $8,450 of offering costs. The Company’s common stock is now listed on the Nasdaq Global Select Market under the ticker symbol “ALGM.”

Prior to the IPO, the Company had two classes of common stock, Class A common stock and Class L common stock. The Company’s Board of Directors authorized 12,500,000 shares of Class A common stock at par value of $0.01, out of which the Company issued 6,720,000 to Sanken in exchange for its previous shares of common stock. The previous single class of common stock was retired in full. The Company sold 2,880,000 shares of newly issued Class A common stock, representing a 28.8% ownership interest, to OEP for cash consideration of $291,000 (the “OEP Transaction”). The stock issuance proceeds were recorded net of $9,260 of related transaction costs. The Company’s Board of Directors authorized 1,000,000 shares of Class L common stock at a par value of $0.01.

Both Class A and Class L common stock were entitled to dividends when, and if, declared by the Board of Directors. Holders of shares of Class A common stock were entitled to a priority dividend of 8%. After holders of shares of Class A

common stock receive an annualized return on capital of 8%, distributions of the remaining value were split between holders of shares of Class A common stock and Class L common stock based on the achievement of certain return targets.

Each outstanding share of Class A common stock entitled the holder to one vote on each matter submitted to a vote of the stockholders of the Company, including the election of the Board of Directors. Holders of Class L common stock were not entitled to vote.

In the event of voluntary or involuntary liquidation, dissolution or winding-up of the Company, any amounts available for distribution by the Company were to be paid to the holders of Class A common stock and Class L common stock, as if such distribution were a dividend paid, factoring in the priorities as described above.

Upon the earliest of (i) an IPO; (ii) change of control; (iii) the date OEP and its affiliates cease to own any shares of capital stock of the Company; or (iv) at the election of the Board of Directors, any merger transaction involving the Company or its subsidiaries, each outstanding share of Class L common stock would convert into Class A common stock.

Also, in connection with the OEP Transaction, the Company granted 400,000 unvested shares of Class A common stock and 597,400 unvested shares of Class L common stock to certain Company employees. The shares of Class A common stock vest to the grantees over a service period of 60 months. However, they remain subject to the Company’s repurchase right at par value in the event that either (i) a change in control has not occurred or (ii) the Company has not consummated an IPO by the seventh anniversary of the OEP Transaction. As of March 27, 2020, the Company was not able to determine whether such a change in control or IPO was probable, and therefore, no amount of stock-based compensation was recognized for the unvested shares of Class A common stock at that time. As a result of the Company’s IPO closing on November 2, 2020, the unvested shares of Class A common stock immediately become vested and the Company recognized $40,440 of one-time stock-based compensation (400,000 shares to management at $101.10 per share) at that time.

The Class L unvested shares vested on a straight-line basis over a service period of four years. Class L unvested shares had no other vesting conditions. If an IPO occurred, 25% of the unvested awards would accelerate vesting if 25% or more of the awards are unvested at the time of the IPO. If a change in control occurs, 100% of the then unvested awards would accelerate vesting. Accordingly, based on the Company’s IPO closing on November 2, 2020, the Company accelerated the vesting of the 25% unvested awards at that time.

Prior to the IPO, the Company issued 17,203 shares of Class L common stock during the nine-month period ended December 25, 2020 with a weighted average price per share of $33.83 and issued 30,300 shares of Class L common stock during the nine-month period ended December 27, 2019 with a weighted average price per share of $26.93.

On October 2, 2020, the Company repurchased an aggregate of 1,997 shares of its Class L common stock from certain of its directors and one of its non-executive employees for an aggregate purchase price of $408 in connection with (i) in the case of such directors, the settlement of certain outstanding promissory notes issued by the Company to such directors, and (ii) in the case of such non-executive employee, to satisfy certain withholding tax obligations triggered by the vesting of such shares in accordance with the terms of the applicable award agreement.

Immediately following the pricing of the IPO on November 2, 2020, all outstanding shares of Class A common stock and Class L common stock were automatically converted into an aggregate of 166,500,000 shares of common stock (the “Common Stock Conversion”). Outstanding shares of Class A and Class L common stock were converted to common stock in the Common Stock Conversion at conversion rates of approximately 15.822 and 13.010 shares of common stock to each share of Class A and Class L common stock, respectively. As part of the Common Stock Conversion, 2,066,508 and 1,766 shares of common stock were returned to the Company for tax payments made on behalf of holders of Class A common stock and Class L common stock, respectively, in withhold to cover tax transactions. Outstanding loan amounts related to Class L common stock in the aggregate amount of $753 were extinguished on October 2, 2020.

The following table presents the respective number of shares of common stock and unvested restricted common stock issued in the Common Stock Conversion. The number of shares of common stock and unvested restricted common stock issuable are based upon the vesting provisions of the outstanding shares and reflect the shares vested and unvested at the date of conversion.


	Shares of Common Stock	Shares of Unvested Restricted Common Stock	Total Shares of Common Stock
Class A common stock	156,155,403	—	156,155,403
Class L common stock	7,816,574	459,749	8,276,323
Total	163,971,977	459,749	164,431,726

Prior to the IPO, there were 638,298 shares of Class L common stock outstanding at a weighted average price per share of $11.99. As noted in the above table, as part of the Common Stock Conversion, the Class L common stock was converted to 7,816,574 shares of common stock and 459,749 of unvested restricted common stock at weighted average prices per share of $14.00.

In connection with its IPO, the Company offered certain employees (excluding its named executive officers) who were eligible to receive cash bonuses under the Company’s LTCIP and TRIP the opportunity to elect to receive RSUs under its 2020 Omnibus Incentive Compensation Plan in lieu of cash payouts under the LTCIP and/or TRIP, through the LTCIP/TRIP Award RSU Conversion Program (the “RSU Conversion Program”). The expense related to the LTCIP and TRIP awards elected to be exchanged in the RSU Conversion Program amounted to $607 and $421, respectively. The number of RSUs granted to employees that elected to participate in the RSU Conversion Program is determined as a percentage of the employee’s target bonus under the LTCIP or TRIP, and amounted to 602,490 and 348,911 RSUs on behalf of the LTCIP and TRIP conversion, respectively, at a grant date fair value of $14.00. If an employee elected to not to participate in the RSU Conversion Program, the LTCIP or TRIP award will continue under its existing terms and conditions.

In addition to above, the Company also issued RSUs to its non-employee directors as consideration for their provision of future services. The stock-based compensation expense related to RSUs is measured based on the fair value market price of the Company’s common shares on the grant date and is recognized on a straight-line basis over the requisite service period, which coincides with the vesting period. RSUs can only be exchanged and settled for the Company’s common shares, on a one-to-one basis, upon vesting. RSUs are generally subject to forfeiture prior to the release of vesting restrictions. Included in the table below is a total amount of 54,644 RSUs issued to such non-employee directors.

The following table summarizes the RSU activity for the nine-month period ended December 25, 2020:


	Number of Shares	Weighted-Average Grant-Date Fair Value		Weighted-Average Remaining Contractual Life (In years)	Aggregate Intrinsic Value
Outstanding - March 27, 2020	—	$	—	—	$	—
Granted	1,426,944	14.04
Vested	(376)	14.00
Canceled	(28,920)	14.00
Outstanding - December 25, 2020	1,397,648	$	14.04	1.74	$	34,648

The weighted-average grant fair value per share for RSUs granted during the nine-month period ended December 25, 2020 was $14.04, and the stock-based compensation expense related to non-vested awards not yet recorded at December 25, 2020 was $17,496, which is expected to be recognized over a weighted-average of 1.74 years. During the nine-month period ended December 25, 2020, 376 shares vested.

The Company also awards PSUs to its senior executive officers based on achievement of medium-term plans (“MTP”) approved in meetings of its Board of Directors for establishing target performances. Each award reflects a target number of shares (“Target Shares”) that may be issued to the award recipient. In fiscal year 2021, these awards are earned upon the completion of a three-year performance period ending March 31, 2023. Whether units are earned at the end of the performance period will be determined based on the achievement of certain performance objectives over the performance period. The performance objectives include achieving certain revenue improvement and cumulative EBITDA levels for the performance period, and also include a performance objective relating to relative total shareholder return (“TSR”). Depending on the results achieved during the three-year performance period, the actual number of shares that a grant recipient may receive at the end of the period ranges from —% to 200% of the Target Shares granted.

The weighted-average fair value of the PSUs was determined using the Monte Carlo simulation model incorporating the following weighted-average assumptions:


			Fiscal Year 2021
Performance term			2.42 years
Volatility			49.9%
Risk-free rate of return			0.17%
Dividend yield			—%
Weighted-average fair value per share			$14.00

The following table summarizes the PSU activity for the nine-month period ended December 25, 2020:


	Number of Shares	Weighted-Average Grant-Date Fair Value		Weighted-Average Remaining Contractual Life (In years)	Aggregate Intrinsic Value
Outstanding - March 27, 2020	—	$	—	—	$	—
Granted	650,302	15.05
Vested	—	—
Canceled	—	—
Outstanding - December 25, 2020	650,302	$	15.05	2.90	$	16,121

PSUs are included at 100% - 200% of target goals. The intrinsic value of the PSU’s vested during the nine-month period ended December 25, 2020 was $16,121. The total compensation cost related to non-vested awards not yet recorded at December 25, 2020 was $9,320, which is expected to be recognized over a weighted average of 2.90 years. No shares were vested during the nine-month period ended December 25, 2020.

The following table summarizes unvested restricted common stock activity for the nine-month period ended December 25, 2020:


	Number of Shares	Weighted-Average Grant-Date Fair Value		Weighted-Average Remaining Contractual Life (In years)	Aggregate Intrinsic Value
Outstanding - March 27, 2020	—	$	—	—	—
Common stock conversion	459,749	14.00
Vested	(37,161)	14.00
Canceled	—	—
Outstanding - December 25, 2020	422,588	$	14.00	2.01	10,476

Upon completion of its IPO, the Company recognized one-time stock-based compensation charges of $40,440 in connection with the vesting of all outstanding shares of Class A common stock, $1,610 in connection with the automatic acceleration of 25% of the standard vesting term of shares of Class L common stock and $1,028 with the RSU Conversion Program (see above and Note 12, “Management Long-Term Cash Incentive Program”). In addition, the Company recognized stock-based compensation charges of $144 and $1,169 for its Class L common stock for the three- and nine-month periods ended December 25, 2020, respectively, and stock-based compensation charges of $2,131, $467 and $73 for its RSUs, PSUs and restricted common stock, respectively, for the three- and nine-month periods ended December 25, 2020. All stock-based compensation charges in fiscal 2020 related to expensing of the Company’s Class L common stock. The Company recorded stock-based compensation expense in the following expense categories of its unaudited consolidated statements of operations:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Cost of sales	$	4,694	$	47	$	4,844	$	137
Research and development	2,984		20		3,037		65
Selling, general and administrative	38,198		236		39,020		849
Total stock-based compensation	$	45,876	$	303	$	46,901	$	1,051

Income Taxes

9 Months Ended

Dec. 25, 2020

Income Tax Disclosure [Abstract]

Income Taxes

The Company recorded the following tax (benefit) provision in its unaudited consolidated statements of operations:


	Three-Month Period Ended						Nine-Month Period Ended
	December 25, 2020			December 27, 2019			December 25, 2020			December 27, 2019
Operating taxes	$	(12,169)		$	1,703		$	(9,764)		$	5,980
Discrete tax items	(18,354)			(161)			(18,149)			5,730
(Benefit) provision for income taxes	$	(30,523)		$	1,542		$	(27,913)		$	11,710
Annual operating tax rate	34.2		%	16.2		%	52.8		%	16.9		%
Effective tax rate	85.8		%	14.7		%	150.9		%	33.0		%

The Company’s provision for income taxes is comprised of the year to date taxes based on an estimate of the annual effective tax rate plus the tax impact of discrete items.

The Company is subject to tax in the United States (“U.S.”) and various foreign jurisdictions. The Company’s effective tax rate can fluctuate primarily based on: the mix of its U.S. and foreign income; the impact of discrete transactions; and the difference between the amount of tax benefit generated by the foreign derived intangible income deduction (“FDII”) and research credits offset by the additional tax from the global intangible low-tax income (“GILTI”) and the base erosion tax (“BEAT”).

The Company regularly assesses the likelihood of outcomes that could result from the examination of its tax returns by the IRS, and other tax authorities to determine the adequacy of its income tax reserves and expense. Should actual events or results differ from the Company’s then-current expectations, charges or credits to the Company’s provision for income taxes may become necessary. Any such adjustments could have a significant effect on the results of operations.

For the three months ended December 25, 2020 and December 27, 2019, the Company’s effective income tax (benefit) expense and rates were a benefit of $30,523 or 85.8% and expense of $1,542 or 14.7% on pre-tax loss of $35,583 and income of $10,500, respectively. For the nine-month period ended December 25, 2020 and December 27, 2019, the Company’s effective income tax (benefit) expense and rates were a benefit of $27,913 or 150.9% and expense of $11,710 or 33.0% on pre-tax loss of $18,501 and income of $35,486, respectively.

The change in effective income tax rates is primarily due to the $40,440 IPO related stock-based compensation charge which significantly reduced U.S. income and was included in the Company’s tax rate from operations in the quarter. The incremental stock-based compensation windfall was treated as a discrete tax adjustment as an incremental tax deduction in the three months ended December 25, 2020. Additionally, other discrete transactions, the divestiture of Polar and the one-time dividend resulted in additional tax deductions. The reduction in U.S. income and the discrete tax deductions resulted in a U.S. tax NOL that can be carried back to refund prior years’ taxes. In total approximately $18,149 of discrete tax benefits recorded this quarter were partially offset by a reduction in our FDII deduction and an increase in GILTI and BEAT tax.

Additionally, in the first quarter of fiscal year 2020, there was a discrete tax expense of approximately $5,500 recorded for the settlement of IRS transfer pricing audits for years 2016, 2017, and 2018.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Related Party Transactions	9 Months Ended
Related Party Transactions	Dec. 25, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Transactions involving Sanken The Company sells products to, and purchases in-process products from, Sanken. In addition, prior to March 28, 2020, the Company also sold products for Sanken. Net sales of Company’s products to Sanken totaled $26,439 and $72,570 during the three- and nine-month periods ended December 25, 2020, respectively, and $16,535 and $49,327 during the three- and nine-month periods ended December 27, 2019, respectively. Trade accounts receivables, net of allowances from Sanken, totaled $17,250 and $30,293 as of December 25, 2020 and March 27, 2020, respectively. Other accounts receivable from Sanken totaled $374 and $558 as of December 25, 2020 and March 27, 2020, respectively. During fiscal year 2020, the Company acted as a distributor of Sanken’s products. Net sales of Sanken’s products by the Company to third parties totaled $7,666 and $26,688 during the three- and nine-month periods ended December 27, 2019, respectively. On March 28, 2020, the Company formally terminated its distribution agreement with Sanken to distribute Sanken’s products. Purchases of various products under the distribution agreement from Sanken totaled $7,356 and $23,835 for the three- and nine-month periods ended December 27, 2019, respectively. Accounts payable to Sanken totaled $4,494 as of March 27, 2020. Joint Development Agreement (“Development Agreement”) The Company, through its former wholly owned subsidiary, PSL, entered into a Development Agreement with Sanken whereby the Company and Sanken jointly own a specific wafer technology and share the reimbursement of development costs incurred by the Company. Sanken reimbursed $360 and $1,080 in the three- and nine-month periods ended December 27, 2019, respectively. Short-term Bridge Loan Receivable to Sanken In March 2019, the Company entered into a short-term bridge loan to Sanken in the amount of $30,000. The loan bore interest at 2.52% and was repaid in April 2019. Interest income related to the loan to Sanken was $55 in the nine-month period ended December 27, 2019. Notes Payable and Line of credit from Sanken The Company, through PSL, its former wholly-owned subsidiary, had related party debt owed to Sanken that included three notes payable in the aggregate amount of $17,700 and two lines-of-credit agreements in the aggregate amount of $25,000 at March 27, 2020. The interest rates on the related party debt was reset at the beginning of each calendar quarter to LIBOR on the last trading day of the previous month, plus a 1.0% spread. Related party interest expense consisting of amounts due to Sanken for intercompany notes payable, lines-of-credit and miscellaneous charges for the three- and nine-month periods ended December 27, 2019 amounted to $334 and $1,129, respectively, and related party interest paid for the same periods amounted to $81 and $835, respectively. As of March 27, 2020, the related party notes payable balance of $17,700 was classified in the consolidated balance sheet as long-term, with various maturity dates through March 14, 2025. The line of credit agreements of $25,000 were classified as current at March 27, 2020. In connection with the PSL divestiture, the total $42,700 balance was contributed in-kind for the fair value of the 70% interest that Sanken acquired. Transactions involving PSL In accordance with the Divestiture Transactions of both PSL and the Sanken distribution business, the Company had both intercompany accounts payable of $1,198 and accounts receivable of $3,368 that were previously eliminated in consolidation. The previous intercompany receivable balance of $3,368 was moved into trade and other accounts receivable due from related party as of March 28, 2020. In addition, as a result of PSL taking over the Sanken distribution business, at December 25, 2020, the Company reflected a related accounts receivable balance of $2,528. This amount includes a reduction of $3,368 from payments made by PSL during the nine-month period ended December 25, 2020. As previously noted above, the Company, through PSL, entered into a Development Agreement with Sanken whereby the Company and Sanken jointly own a specific wafer technology and share the reimbursement of development costs incurred by the Company. Sanken reimbursed no amounts in the three- and nine-month periods ended December 25, 2020 and $360 and $1,080 in the three- and nine-month periods ended December 27, 2019, respectively. In April 2015, PSL and Sanken entered into a discrete technology development agreement (as amended, the “Discrete Technology Development Agreement”), pursuant to which the parties agreed upon the general terms under which they, from time to time, undertook certain activities (the “Discrete Development Activities”) to develop new technologies to be used by PSL to manufacture products for Sanken, as well as the ownership and use of such technologies following their development. In June 2018, the Company, PSL and Sanken entered into an amendment to the Discrete Technology Development Agreement pursuant to which the parties agreed to the assignment of all rights and obligations of PSL under such agreement to the Company and to certain amendments to the terms of such agreement. The Discrete Technology Development Agreement provided that the expenses for all Discrete Development Activities to be shared equally by the Company and Sanken on an annual basis (subject to any exceptions upon which the parties agreed to from time to time). During the three- and nine-month periods ended December 25, 2020 and December 27, 2019, the Company did not pay any fees to PSL pursuant to the Discrete Technology Development Agreement. In May 2009, the Company entered into a technology development agreement (the “IC Technology Development Agreement”) with Polar Semiconductor, Inc., the predecessor of PSL (“PSI”) and Sanken, pursuant to which the parties agreed upon the general terms under which they may, from time to time, undertake certain activities (the “IC Process Development Activities”) to develop new technologies to be used by PSI to manufacture products for the Company and Sanken, as well as the ownership and use of such technologies following their development. The IC Technology Development Agreement provides that the expenses for all IC Process Development Activities will be shared equally by the Company and Sanken on an annual basis (subject to any exceptions upon which the parties may agree from time to time), with such expenses being paid to PSI by Sanken in the form of an up-front annual fee, with PSI being responsible for any expenses that exceed the amount of such fee. The IC Technology Development Agreement will continue in effect until such time as the Company, PSL and Sanken mutually agree to its termination or adopt a successor agreement, or in the event the companies fail to agree upon the annual fee for a fiscal year within three months after the commencement of such fiscal year. During both of the three- and nine-month periods ended December 25, 2020 and December 27, 2019, the Company (through PSL) received fees of $300 and $900 from Sanken pursuant to the IC Technology Development Agreement, and during the three- and nine- month periods ended December 25, 2020 the Company paid fees of $300 and $900 to PSL pursuant to the IC Technology Development Agreement. The Company continues to purchase in-process products from PSL. Purchases of various products from PSL totaled $11,558 and $33,448 for the three- and nine-month periods ended December 25, 2020, respectively. These amounts include $1,500 and $5,000 of price support payments made for the three- and nine-month periods ended December 25, 2020, respectively, and the reduction of $1,157 and $1,198 of intercompany balances for the three- and nine-month periods ended December 25, 2020, respectively. Accounts payable to PSL included in amounts due to related party totaled $2,078 as of December 25, 2020. Note Receivable from PSL On March 28, 2020, in connection with the PSL divestiture, the Company contributed the forgiveness of the fair value of $15,000 out of the $66,377 total debt owed by PSL to the Company, which was previously eliminated in consolidation as of March 27, 2020. As a result of this divestiture, on March 28, 2020, the $51,377 note receivable from PSL was classified on the Company’s balance sheet as related party note receivable. The related party note receivable held by the Company had a maturity date of March 28, 2027 and bore interest at a rate of 2.70%, which was a market rate determined by IRS guidance at the time of the divestiture. The entire receivable of $51,377 plus accrued interest of $762 was repaid on October 14, 2020. Consulting Agreement The Company entered into a board executive advisor agreement (the “Consulting Agreement”) with Reza Kazerounian in December 2017, before Mr. Kazerounian became a member of the Company’s board of directors, pursuant to which the Company engaged Mr. Kazerounian to serve as executive advisor to the board of directors and the office of Chief Executive Officer. The Consulting Agreement provides for a fee payable to Mr. Kazerounian on a monthly basis in exchange for his services (which fee was reduced from $30 per month to $19 per month in connection with Mr. Kazerounian’s appointment to the board of directors in June 2018), as well as a grant of 12,000 shares of the Company’s Class L common stock and a signing bonus of $54 in connection with the execution of the Consulting Agreement. The Consulting Agreement provides that if Mr. Kazerounian is terminated by the board of directors, he will be entitled to a severance payment in the amount of $180 as well as a six-month vesting acceleration of his shares of Class L common stock. The board of directors and Mr. Kazerounian each have the right to terminate the Consulting Agreement at any time. During the nine-month periods ended December 25, 2020 and December 27, 2019, the Company paid aggregate fees of $262 and $270, respectively, to Mr. Kazerounian pursuant to the Consulting Agreement. Director and Executive Officer Promissory Notes From time to time, the Company entered into promissory notes with certain of its directors and executive officers to finance all or a part of the income and employment taxes payable by them in connection with grants of the Company’s Class A common stock and/or Class L common stock. The Company had $506 of promissory notes outstanding as of as of March 27, 2020. On October 2, 2020, the Company repurchased an aggregate of 1,997 shares of its Class L common stock from certain of its directors and one of its non-executive employees for an aggregate purchase price of $408 in connection with, (i) in the case of such directors, the settlement of certain outstanding promissory notes issued by the Company to such directors, and (ii) in the case of such non-executive employee, to satisfy certain withholding tax obligations triggered by the vesting of such shares in accordance with the terms of the applicable award agreement. As a result of these transactions, there were no promissory notes outstanding as of December 25, 2020.

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 25, 2020
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and disclosures of contingencies at the date of the unaudited consolidated financial statements and the reported amounts of net sales and expenses during the reporting period. Such estimates relate to useful lives of fixed and intangible assets, allowances for doubtful accounts and customer returns and sales allowances. Such estimates could also relate to the fair value of acquired assets and liabilities, including goodwill and intangible assets, net realizable value of inventory, accrued liabilities, the valuation of stock-based awards, deferred tax valuation allowances, and other reserves. On an ongoing basis, management evaluates its estimates. Actual results could differ from those estimates, and such differences may be material to the unaudited condensed consolidated financial statements.
Deferred Offering Costs	Deferred Offering Costs The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in stockholder’s equity as a reduction of the additional paid-in capital generated as a result of the offering.
Concentrations of Credit Risk and Significant Customers	Concentrations of Credit Risk and Significant Customers Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents and accounts receivable. The Company maintains its cash and cash equivalents with financial institutions, which management believes to be of a high credit quality. To manage credit risk related to accounts receivables, the Company evaluates the creditworthiness of its customers and maintains allowances, to the extent necessary, for potential credit losses based upon the aging of its accounts receivable balances and known collection issues.
Impact of Recently Issued Accounting Standards	Impact of Recently Issued Accounting Standards The Company qualifies as “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has elected to “opt in” to the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company will adopt the new or revised standard at the time nonpublic companies adopt the new or revised standard and will do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company. The Company may choose to early adopt any new or revised accounting standards whenever such early adoption is permitted for nonpublic companies. In February 2016, the Financial Accounting Standards Board (“FASB”) issued its new lease accounting guidance in ASU No. 2016-02, “Leases (Topic 842)” (“ASU 2016-02” or “the new lease standard”), subsequently amended by ASU 2018-11, Leases (Topic 842): Targeted Improvements. Under the new guidance, lessees will be required to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. Lessees will no longer be provided with a source of off-balance sheet financing. The new lease guidance also simplifies the accounting for sale and leaseback transactions primarily because lessees must recognize lease assets and lease liabilities. The standard is effective for public companies for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years (i.e., January 1, 2019, for a calendar-year entity). Early application is permitted. Entities have the option of using either a modified retrospective approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, or else a transition option (which the Company expects to use) allowing lessees to not apply the new lease standard in comparative periods but instead recognize a cumulative-effect adjustment to retained earnings as of the date of adoption. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. Lessees and lessors may not apply a full retrospective transition approach. In May 2020, FASB issued ASU No. 2020-05 delaying the effective date of the new lease standard for nonpublic companies to fiscal years beginning after December 15, 2021 and interim periods within those fiscal years beginning after December 15, 2022. The Company expects to adopt this guidance during fiscal year 2022 and its assessment of the impact of adopting this standard is underway, including cataloging all leases, performing a preliminary analysis of the amounts of lease liabilities and right-of-use assets to be recorded and reviewing potential changes to the disclosures on leases. Based on this preliminary assessment, the Company does not expect the adoption of this standard to have a significant impact on its consolidated statement of operations. However, the Company expects that the recognition of right-of-use assets and corresponding lease liabilities will have a significant impact on its consolidated balance sheet. In June 2016, the FASB issued ASU No. 2016-13, “Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”), which adds an impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses, which the FASB believes will result in more timely recognition of such losses. The ASU is also intended to reduce the complexity by decreasing the number of credit impairment models that entities use to account for debt instruments. ASU 2016-03, along with its subsequent clarifications, was effective for public companies beginning after December 15, 2019 and is effective for nonpublic companies for fiscal years beginning after December 15, 2021. The Company is evaluating the new guidance and the expected effect on its consolidated financial statements and related disclosures. In November 2019, the FASB issued ASU No. 2019-10 delaying the effective date for all entities. For public entities, this guidance was effective for annual periods beginning after December 15, 2019, including interim periods within those fiscal years. For nonpublic entities, this guidance is effective for annual periods beginning after December 15, 2022, including interim periods within those fiscal years. In August 2018, the FASB issued ASU No. 2018-14, “Compensation—Retirement Benefits—Defined Benefit Plans—General (Topic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans” (“ASU 2018-14”), which modifies the disclosure requirements for defined benefit pension plans and other postretirement plans. ASU 2018-14 should be applied on a retrospective transition basis, and it is effective for public companies beginning after December 15, 2020 and for nonpublic companies beginning after December 15, 2021. The Company is evaluating the new guidance and the expected effect on its consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement” (“ASU 2018-13”), which modifies the disclosure requirements on fair value measurements in Topic 820, Fair Value Measurement, regarding transfers between levels of financial instruments, amounts of unrealized gains and losses included in other comprehensive (loss) income for Level 3 fair value measurements and the information used to determine the fair value of Level 3 fair value measurements. The standard is effective for both public and nonpublic companies, for annual periods beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted. The Company is currently assessing the potential impact that the adoption of ASU 2018-13 will have on its consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 simplifies the accounting for income taxes by removing certain exceptions for intraperiod tax allocations and deferred tax liabilities for equity method investments and adds guidance on whether a step-up in tax basis of goodwill relates to a business combination or a separate transaction. This ASU is effective for fiscal years beginning after December 15, 2020 for public companies and for fiscal years beginning after December 15, 2021 for nonpublic companies, with early adoption permitted. The Company is evaluating the new guidance and the expected effect on its consolidated financial statements and related disclosures. In January 2020, the FASB issued ASU No. 2020-01, “Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)” (“ASU 2020-01”), which addresses accounting for the transition into and out of the equity method and provides clarification of the interaction of rules for equity securities, the equity method of accounting, and forward contracts and purchase options on certain types of securities. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020 for public companies and beginning after December 15, 2021 for nonpublic entities with early adoption permitted. The Company is currently assessing the potential impact that the adoption of ASU 2020-01 will have on its consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting” (“ASU 2020-04”) to provide temporary optional expedients and exceptions to the contract modifications, hedge relationships, and other transactions affected by reference rate reform if certain criteria are met. This ASU, which was effective for all entities upon issuance on March 12, 2020 and may be applied through December 31, 2022, is applicable to all contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or any other reference rate expected to be discontinued. The Company is still assessing the impact that the adoption of ASU 2020-04 will have on its consolidated financial statements.

Nature of the Business and Basis of Presentation (Tables)

9 Months Ended

Dec. 25, 2020

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Cash Flow Impact of Divestiture

In accordance with the PSL Divestiture noted above, the following noncash assets and liabilities and related equity impacts attributable to the unaudited statement of cash flows are summarized below:


	March 28, 2020
Cash and cash equivalents	$	(15,332)
Restricted cash	(1,013)
Trade accounts receivable, net of allowances	37
Accounts receivable – other	(308)
Inventories	(32,250)
Prepaid expenses and other current assets	(376)
Property, plant and equipment, net	(115,341)
Related party note receivable	51,377
Equity investment in related party	25,462
Other assets, net	5,609
Trade accounts payable	4,176
Accrued expenses and other current liabilities	7,150
Current portion of related party debt	25,000
Bank lines-of-credit	10,000
Related party notes payable, less current portion	17,700
Other long-term liabilities	(1,247)
Additional paid-in capital	19,165

Acquisition (Tables)

9 Months Ended

Dec. 25, 2020

Business Combinations [Abstract]

Summary of Preliminary Purchase Price Allocation

The following table summarizes the preliminary purchase price allocation recorded:


Estimated fair value of consideration:
Base purchase price	$	27,281
Contingent Consideration	7,800
Total estimated fair value of consideration	$	35,081
Estimated fair value of assets acquired and liabilities assumed:
Net working capital	$	4,064
Property and equipment	57
Finite-life intangible assets	13,600
Indefinite-life intangible assets	2,400
Deferred tax liability	(3,843)
Goodwill	18,803
Allocated purchase price	$	35,081

Schedule of Finite-Lived Intangible Assets Acquired

The following table presents the estimated fair values and useful lives of the identifiable finite-life intangible assets acquired:


	Useful Life	Fair value
Completed technology	12 years	$	13,100
Customer relationships	6 years	300
Trademarks	5 years	200
		$	13,600

Revenue from Contract with Customers (Tables)

9 Months Ended

Dec. 25, 2020

Revenue from Contract with Customer [Abstract]

Net Sales by Core End Market and Application

Net sales by core end market and application:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Core end market:
Automotive	$	113,902	$	99,074	$	279,759	$	289,681
Industrial	23,654		21,358		65,710		56,095
Other	26,893		15,070		70,630		53,399
Other applications:
Wafer foundry products	—		16,634		—		49,622
Distribution of Sanken products	—		7,666		—		26,688
Total net sales	$	164,449	$	159,802	$	416,099	$	475,485

Revenue from External Customers by Products and Services

Net sales by product:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Power integrated circuits (“PIC”)	$	54,406	$	43,665	$	146,276	$	123,900
Magnetic sensors (“MS”)	109,457		91,837		268,956		275,275
Photonics	586		—		867		—
Wafer foundry products	—		16,634		—		49,622
Distribution of Sanken products	—		7,666		—		26,688
Total net sales	$	164,449	$	159,802	$	416,099	$	475,485

Revenue from External Customers by Geographic Areas

Net sales by geography:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Americas:
United States	$	23,934	$	27,498	$	57,892	$	86,746
Other Americas	5,620		4,722		10,797		15,930
EMEA:
Europe	28,239		24,341		70,459		76,622
Asia:
Japan	26,439		46,010		72,570		131,950
Greater China	46,172		35,284		116,178		95,244
South Korea	17,606		14,119		43,733		41,413
Other Asia	16,439		7,828		44,470		27,580
Total net sales	$	164,449	$	159,802	$	416,099	$	475,485

Fair Value Measurements (Tables)

9 Months Ended

Dec. 25, 2020

Fair Value Disclosures [Abstract]

Fair Value, by Balance Sheet Grouping


	Fair Value Measurement at December 25, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market fund deposits	$	16,320	$	—	$	—	$	16,320
Restricted cash:
Money market fund deposits	6,520		—		—		6,520
Total assets	$	22,840	$	—	$	—	$	22,840
Liabilities:
Other long-term liabilities:
Contingent consideration	$	—	$	—	$	7,800	$	7,800
Total liabilities	$	—	$	—	$	7,800	$	7,800


	Fair Value Measurement at March 27, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market fund deposits	$	46,337	$	—	$	—	$	46,337
Restricted cash:
Money market fund deposits	5,385		—		—		5,385
Total assets	$	51,722	$	—	$	—	$	51,722

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation

The following table shows the change in fair value of Level 3 contingent consideration in connection with the Acquisition for the nine-month period ended December 25, 2020:


	Level 3 Contingent Consideration
Balance at March 27, 2020	$	—
Additions during the year	7,800

Balance at December 25, 2020	$	7,800

Trade Accounts Receivable, net (Tables)

9 Months Ended

Dec. 25, 2020

Receivables [Abstract]

Schedule of Trade Accounts Receivable, Net

Trade accounts receivable, net (including related party trade accounts receivable) consisted of the following:


	December 25, 2020		March 27, 2020
Trade accounts receivable	$	103,687	$	107,223
Less:
Allowance for doubtful accounts	(138)		(288)
Returns and sales allowances	(16,437)		(17,185)
Related party trade accounts receivable	(19,778)		(30,293)
Total	$	67,334	$	59,457

Schedule of Changes in Allowance for Doubtful Accounts and Returns and Sales Allowances

Changes in the Company’s allowance for doubtful accounts and returns and sales allowances were as follows:


Description	Allowance for Doubtful Accounts		Returns and Sales Allowances		Total
Balance at March 27, 2020	$	288	$	17,185	$	17,473
Charged to costs and expenses or revenue	(150)		103,660		103,510
Write-offs, net of recoveries	—		(104,408)		(104,408)
Balance at December 25, 2020	$	138	$	16,437	$	16,575


Description	Allowance for Doubtful Accounts		Returns and Sales Allowances		Total
Balance at March 29, 2019	$	412	$	17,607	$	18,019
Charged to costs and expenses or revenue	(175)		91,690		91,515
Write-offs, net of recoveries	—		(92,330)		(92,330)
Balance at December 27, 2019	$	237	$	16,967	$	17,204

Inventories (Tables)

9 Months Ended

Dec. 25, 2020

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories include material, labor and overhead and consisted of the following:


	December 25, 2020		March 27, 2020
Raw materials and supplies	$	8,689	$	12,411
Work in process	57,477		87,606
Finished goods	24,451		24,659
Finished goods – consigned	3,404		2,551
Total	$	94,021	$	127,227

Property, Plant and Equipment, net (Tables)

9 Months Ended

Dec. 25, 2020

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant, and Equipment

Property, plant and equipment, net is stated at cost, and consisted of the following:


	December 25, 2020		March 27, 2020
Land	$	23,829	$	27,898
Buildings, building improvements and leasehold improvements	91,535		150,402
Machinery and equipment	488,796		694,215
Office equipment	6,643		7,517
Construction in progress	10,956		27,919
Total	621,759		907,951
Less accumulated depreciation	(407,387)		(575,621)
Total	$	214,372	$	332,330

Schedule of Long-lived Assets

The geographic locations of the Company's long-lived assets, net, based on physical location of the assets, as of December 25, 2020 and March 27, 2020 are as follows:


	December 25, 2020		March 27, 2020
United States	$	35,894	$	152,536
Philippines	136,284		106,618
Thailand	34,226		62,380
Other	9,306		12,112
Total	$	215,710	$	333,646

Goodwill and Intangible Assets (Tables)

9 Months Ended

Dec. 25, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Summary of Changes in Carrying Amount of Goodwill

The table below summarizes the changes in the carrying amount of goodwill as follows:


	Total
Balance at March 27, 2020	$	1,285
Goodwill arising from Acquisition	18,803
Currency translation	161
Balance at December 25, 2020	$	20,249

Schedule of Intangible Assets, Net

Intangible assets, net is as follows:


	December 25, 2020
Description	Gross		Accumulated Amortization		Net Carrying Amount		Weighted- Average Lives
Patents	$	31,852	$	11,661	$	20,191	10 years
Customer relationships	6,193		5,823		370		9 years
Process technology	17,150		2,028		15,122		12 years
Trademarks	810		73		737		5 years
Other	32		32		—
Total	$	56,037	$	19,617	$	36,420


	March 27, 2020
Description	Gross		Accumulated Amortization		Net Carrying Amount		Weighted- Average Lives
Patents	$	29,115	$	9,834	$	19,281	10 years
Customer relationships	5,462		5,335		127		9 years
Process technology	1,650		1,650		—
Trademarks	608		58		550
Other	32		32		—
Total	$	36,867	$	16,909	$	19,958

Schedule of Annual Amortization Expense

As of December 25, 2020, annual amortization expense of intangible assets for the next five fiscal years is expected to be as follows:


Remainder of 2021	$	850
2022	3,293
2023	3,139
2024	3,003
2025	2,709
Thereafter	23,426
Total	$	36,420

Other Assets, net (Tables)

9 Months Ended

Dec. 25, 2020

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of Other Assets, Net

The composition of other assets, net is as follows:


	December 25, 2020		March 27, 2020
VAT receivables long-term, net	$	6,662	$	3,039
Deposits	2,414		2,399
Prepaid contracts long-term	1,478		1,282

Other	1,928		2,090
Total	$	12,482	$	8,810

Accrued Expenses and Other Current Liabilities (Tables)

9 Months Ended

Dec. 25, 2020

Payables and Accruals [Abstract]

Schedule of Accrued Expenses and Other Current Liabilities

The composition of accrued expenses and other current liabilities is as follows:


	December 25, 2020		March 27, 2020
Accrued management incentive (LTCIP)	$	94	$	11,488
Accrued management incentive (non-LTCIP)	14,143		6,273
Accrued salaries and wages	18,603		12,069
Base acquisition purchase price due	17,244		—
Accrued vacation	5,534		7,146
Accrued severance	2,643		6,065
Accrued professional fees	1,057		4,036
Accrued income taxes	1,803		3,408
Accrued utilities	628		1,114
Other current liabilities	5,030		5,256
Total	$	66,779	$	56,855

Management Long-Term Incentive Plan (Tables)

9 Months Ended

Dec. 25, 2020

Schedule of Accrual Activity, Payments, Removal Due to Divestitures and Balances Related to the LTIP

The accrual activity, payments, removal due to divestitures and balances related to the LTCIP are as follows:


Description	Current Liabilities		Long-Term Liabilities
Balance at March 27, 2020	$	11,488	$	2,439
Reclassification	1,004		(1,004)
Payments	(11,096)		—
RSU conversion	(640)		—
Removal due to divestiture	(378)		(398)
Accruals	(284)		(843)
Balance at December 25, 2020	$	94	$	194

Debt and Other Borrowings (Tables)

9 Months Ended

Dec. 25, 2020

Debt Disclosure [Abstract]

Summary of Components of Debt

The following is a summary of obligations under the Company’s Senior Secured Credit Facilities and other borrowings at December 25, 2020 and March 27, 2020:


	December 25, 2020		March 27, 2020
Senior Secured Term Loan	$	25,000	$	—

Unsecured Revolving Credit Facilities	—		43,000
Total Debt	25,000		43,000
Less debt payable within one year	—		43,000
Debt payable after one year	$	25,000	$	—

Schedule of Principal Maturities of Debt Obligations

The principal maturities of debt obligations outstanding were as follows at December 25, 2020:


Remainder of 2021	$	—
2022	—
2023	—
2024	—
2025	—
Thereafter	25,000
Total	$	25,000

Other Long-Term Liabilities (Tables)

9 Months Ended

Dec. 25, 2020

Other Liabilities Disclosure [Abstract]

Schedule of Other Long-Term Liabilities

The composition of other long-term liabilities is as follows:


	December 25, 2020		March 27, 2020
Accrued management incentive (LTCIP)	$	194	$	2,439
Accrued management incentive (non-LTCIP)	318		2,304
Accrued retirement	9,516		8,005
Accrued contingent consideration	7,800		—
Provision for uncertain tax positions (net)	2,758		2,855
Other	275		275
Total	$	20,861	$	15,878

Retirement Plans (Tables)

9 Months Ended

Dec. 25, 2020

Retirement Benefits [Abstract]

Schedule of Expense Related to Defined Benefit Plan

Expense related to the non-U.S. defined benefit plan was as follows:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Service cost	$	296	$	242	$	843	$	717
Interest cost	166		169		474		503
Expected return on plan assets	(79)		(83)		(231)		(247)

Amortization of net transition asset	—		(4)		—		(10)
Amortization of prior service cost	2		2		6		6
Actuarial loss	47		24		126		72
Net periodic pension expense	$	432	$	350	$	1,218	$	1,041

Fair Value of Entity's Plan Assets


	Fair Value at December 25, 2020		Level 1		Level 2		Level 3
Assets of non-U.S. defined benefit plan:
Government securities	$	1,826	$	1,826	$	—	$	—
Unit investment trust fund	1,155		—		1,155		—
Loans	562		—		—		562
Bonds	1,193		—		1,193		—
Stocks and other investments	2,353		1,205		1		1,147
Total	$	7,089	$	3,031	$	2,349	$	1,709


	Fair Value at March 27, 2020		Level 1		Level 2		Level 3
Assets of non-U.S. defined benefit plan:
Government securities	$	1,260	$	1,260	$	—	$	—
Unit investment trust fund	897		—		897		—
Loans	756		—		—		756
Bonds	1,094		—		1,094		—
Stocks and other investments	1,572		1,207		1		364
Total	$	5,579	$	2,467	$	1,992	$	1,120

Schedule of Changes in Fair Value of Level 3 Plan Assets

The following table shows the change in fair value of Level 3 plan assets for the nine-month period ended December 25, 2020:


	Level 3 Non-U.S. Defined Plan Assets
	Loans		Stocks
Balance at March 27, 2020	$	756	$	364
Additions during the year	207		—
Redemptions during the year	(440)		—
Revaluation of equity securities	—		753
Change in foreign currency exchange rates	39		30
Balance at December 25, 2020	$	562	$	1,147

Net (Loss) Income per Share (Tables)

9 Months Ended

Dec. 25, 2020

Earnings Per Share [Abstract]

Schedule of Computation of Net (Loss) Income per Share and Unaudited Pro Forma Net Income per Share


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Net (loss) income attributable to Allegro MicroSystems, Inc.	$	(5,095)	$	8,926	$	9,309	$	23,675
Net (loss) income attributable to common stockholders	(5,060)		8,958		9,412		23,776
Basic weighted average shares of common stock	124,363,078		10,000,000		48,121,026		10,000,000
Dilutive effect of common stock equivalents	—		—		123,517,761		—
Diluted weighted average shares of common stock	124,363,078		10,000,000		171,638,787		10,000,000
Basic net (loss) income attributable to Allegro MicroSystems, Inc. per share	$	(0.04)	$	0.89	$	0.19	$	2.37
Basic net (loss) income attributable to common stockholders per share	$	(0.04)	$	0.90	$	0.20	$	2.38
Diluted net (loss) income attributable to Allegro MicroSystems, Inc. per share	$	(0.04)	$	0.89	$	0.05	$	2.37
Diluted net (loss) income attributable to common stockholders per share	$	(0.04)	$	0.90	$	0.05	$	2.38

Schedule of Issuable Weighted Average Share Information

The following represents issuable weighted average share information for the respective periods:


	Three-Month Period Ended		Nine-Month Period Ended
	December 25, 2020	December 27, 2019	December 25, 2020	December 27, 2019
Unvested restricted stock units (“RSUs”)	377,767	—	125,922	—
Unvested performance stock units (“PSUs”)	422,768	—	140,923	—
Shares related to Common Stock Conversion	56,752,747	—	123,250,916	—
Total	57,553,282	—	123,517,761	—

Common Stock and Stock-Based Compensation (Tables)

9 Months Ended

Dec. 25, 2020

Share-based Payment Arrangement [Abstract]

Schedule of Stock Issued in Common Stock Conversion


	Shares of Common Stock	Shares of Unvested Restricted Common Stock	Total Shares of Common Stock
Class A common stock	156,155,403	—	156,155,403
Class L common stock	7,816,574	459,749	8,276,323
Total	163,971,977	459,749	164,431,726

Schedule of Restricted Stock Units Activity

The following table summarizes the RSU activity for the nine-month period ended December 25, 2020:


	Number of Shares	Weighted-Average Grant-Date Fair Value		Weighted-Average Remaining Contractual Life (In years)	Aggregate Intrinsic Value
Outstanding - March 27, 2020	—	$	—	—	$	—
Granted	1,426,944	14.04
Vested	(376)	14.00
Canceled	(28,920)	14.00
Outstanding - December 25, 2020	1,397,648	$	14.04	1.74	$	34,648

Schedule of Performance Units Fair Value Assumptions

The weighted-average fair value of the PSUs was determined using the Monte Carlo simulation model incorporating the following weighted-average assumptions:


			Fiscal Year 2021
Performance term			2.42 years
Volatility			49.9%
Risk-free rate of return			0.17%
Dividend yield			—%
Weighted-average fair value per share			$14.00

Summary of Performance Stock Units Activity

The following table summarizes the PSU activity for the nine-month period ended December 25, 2020:


	Number of Shares	Weighted-Average Grant-Date Fair Value		Weighted-Average Remaining Contractual Life (In years)	Aggregate Intrinsic Value
Outstanding - March 27, 2020	—	$	—	—	$	—
Granted	650,302	15.05
Vested	—	—
Canceled	—	—
Outstanding - December 25, 2020	650,302	$	15.05	2.90	$	16,121

Summary of Unvested Restricted Common Stock Activity

The following table summarizes unvested restricted common stock activity for the nine-month period ended December 25, 2020:


	Number of Shares	Weighted-Average Grant-Date Fair Value		Weighted-Average Remaining Contractual Life (In years)	Aggregate Intrinsic Value
Outstanding - March 27, 2020	—	$	—	—	—
Common stock conversion	459,749	14.00
Vested	(37,161)	14.00
Canceled	—	—
Outstanding - December 25, 2020	422,588	$	14.00	2.01	10,476

Schedule of Stock-Based Compensation Expense

The Company recorded stock-based compensation expense in the following expense categories of its unaudited consolidated statements of operations:


	Three-Month Period Ended				Nine-Month Period Ended
	December 25, 2020		December 27, 2019		December 25, 2020		December 27, 2019
Cost of sales	$	4,694	$	47	$	4,844	$	137
Research and development	2,984		20		3,037		65
Selling, general and administrative	38,198		236		39,020		849
Total stock-based compensation	$	45,876	$	303	$	46,901	$	1,051

Income Taxes (Tables)

9 Months Ended

Dec. 25, 2020

Income Tax Disclosure [Abstract]

Schedule of Tax (Benefit) Provision

The Company recorded the following tax (benefit) provision in its unaudited consolidated statements of operations:


	Three-Month Period Ended						Nine-Month Period Ended
	December 25, 2020			December 27, 2019			December 25, 2020			December 27, 2019
Operating taxes	$	(12,169)		$	1,703		$	(9,764)		$	5,980
Discrete tax items	(18,354)			(161)			(18,149)			5,730
(Benefit) provision for income taxes	$	(30,523)		$	1,542		$	(27,913)		$	11,710
Annual operating tax rate	34.2		%	16.2		%	52.8		%	16.9		%
Effective tax rate	85.8		%	14.7		%	150.9		%	33.0		%

Nature of the Business and Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands				1 Months Ended		3 Months Ended		9 Months Ended
	Nov. 02, 2020 USD ($) $ / shares shares	Oct. 14, 2020 USD ($)	Mar. 28, 2020 USD ($)	Mar. 31, 2020 USD ($)	Oct. 31, 2017	Dec. 25, 2020 USD ($) location continent	Mar. 27, 2020 USD ($)	Dec. 25, 2020 USD ($) location continent	Dec. 27, 2019 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Percentage of ownership interest sold					0.288
Number of locations \| location						16		16
Number of continents on which entity operates \| continent						4		4
Noncash or Part Noncash Divestitures [Line Items]
Noncash or part noncash divestiture, amount of consideration received								$ 0	$ 0
Equity investment in related party						$ 26,657	$ 0	26,657
Adjustments to additional paid in capital, capitalization changes						(527)		19,165
IPO
Noncash or Part Noncash Divestitures [Line Items]
Number of shares issued in transaction (in shares) \| shares	28,750,000
Offering price (in dollars per share) \| $ / shares	$ 14.00
Net proceeds	$ 321,425
Underwriting discounts	20,125
Estimated offering costs	$ 8,450
IPO - Selling Shareholders
Noncash or Part Noncash Divestitures [Line Items]
Number of shares issued in transaction (in shares) \| shares	3,750,000
COVID-19
Noncash or Part Noncash Divestitures [Line Items]
Proceeds from lines of credit				$ 43,000			$ 43,000
Estimated cash benefit, CARES Act, net operating losses						8,963		8,963
Estimated cash benefit, CARES Act, qualified improvement property						1,680		1,680
Estimated deferred payroll taxes, CARES Act						2,766		2,766
Estimated deferred payroll taxes, CARES Act, to be paid, third quarter of fiscal year 2022						1,383		1,383
Allegro Microsystems, Inc. \| IPO
Noncash or Part Noncash Divestitures [Line Items]
Number of shares issued in transaction (in shares) \| shares	25,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL
Noncash or Part Noncash Divestitures [Line Items]
Noncash or part noncash divestiture, amount of consideration received			$ 42,700
Noncash or part noncash divestiture, amount of consideration transferred			$ 15,000
Equity method investment, ownership percentage			30.00%
Equity investment in related party			$ 25,250
Income from equity method investments						949		1,407
Adjustments to additional paid in capital, capitalization changes								19,165
Adjustments to additional paid in capital, income tax benefit from noncash or part noncash divestiture								1,552
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL \| Sanken
Noncash or Part Noncash Divestitures [Line Items]
Ownership percentage by majority shareholder			70.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL \| PSL
Noncash or Part Noncash Divestitures [Line Items]
Related party debt			$ 66,377
Repayments of related party notes receivable		$ 51,377
Note receivable from related party						51,377		51,377
Interest paid		762
Interest payable		$ 762				$ 762		$ 762

Nature of the Business and Basis of Presentation - Cash Flow Impact of Divestiture (Details) - PSL - Disposal Group, Disposed of by Sale, Not Discontinued Operations $ in Thousands	Mar. 28, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash and cash equivalents	$ (15,332)
Restricted cash	(1,013)
Trade accounts receivable, net of allowances	37
Accounts receivable – other	(308)
Inventories	(32,250)
Prepaid expenses and other current assets	(376)
Property, plant and equipment, net	(115,341)
Related party note receivable	51,377
Equity investment in related party	25,462
Other assets, net	5,609
Trade accounts payable	4,176
Accrued expenses and other current liabilities	7,150
Current portion of related party debt	25,000
Bank lines-of-credit	10,000
Related party notes payable, less current portion	17,700
Other long-term liabilities	(1,247)
Additional paid-in capital	$ 19,165

Summary of Significant Accounting Policies - Deferred Offering Costs (Details) - USD ($)	Dec. 25, 2020	Mar. 27, 2020
Accounting Policies [Abstract]
Deferred financing costs	$ 0	$ 0

Summary of Significant Accounting Policies - Concentrations of Credit Risk and Significant Customers (Details)	3 Months Ended			9 Months Ended
	Dec. 25, 2020	Jun. 26, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Revenue Benchmark \| Geographic Concentration Risk \| Non-US
Concentration Risk [Line Items]
Concentration risk, percentage	85.40%		82.80%	86.10%	81.80%
Revenue Benchmark \| Geographic Concentration Risk \| Greater China
Concentration Risk [Line Items]
Concentration risk, percentage	28.10%		22.10%	27.90%	20.00%
Revenue Benchmark \| Geographic Concentration Risk \| Japan
Concentration Risk [Line Items]
Concentration risk, percentage	16.00%		28.80%	17.40%	27.80%
Revenue Benchmark \| Geographic Concentration Risk \| South Korea
Concentration Risk [Line Items]
Concentration risk, percentage	10.70%			10.50%
Sanken \| Trade Accounts Receivable \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage		33.80%		19.80%
Sanken \| Revenue Benchmark \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	16.10%		10.30%	17.40%	10.40%

Acquisition - Additional Information (Details) $ in Thousands		9 Months Ended
	Aug. 28, 2020 USD ($)	Dec. 25, 2020 reportingUnit
Business Acquisition [Line Items]
Number of reporting units \| reportingUnit		1
Voxtel
Business Acquisition [Line Items]
Preliminary purchase price	$ 35,081
Potential payout	15,000
Fair value of earn-outs	7,800
Indefinite-life intangible assets	$ 2,400

Acquisition - Summary of Preliminary Purchase Price Allocation (Details) - USD ($) $ in Thousands	Aug. 28, 2020	Dec. 25, 2020	Mar. 27, 2020
Estimated fair value of assets acquired and liabilities assumed:
Goodwill		$ 20,249	$ 1,285
Voxtel
Estimated fair value of consideration:
Base purchase price	$ 27,281
Contingent Consideration	7,800
Total estimated fair value of consideration	35,081
Estimated fair value of assets acquired and liabilities assumed:
Net working capital	4,064
Property and equipment	57
Finite-life intangible assets	13,600
Indefinite-life intangible assets	2,400
Deferred tax liability	(3,843)
Goodwill	18,803
Allocated purchase price	$ 35,081

Acquisition - Schedule of Finite-Lived Intangible Assets Acquired (Details) - Voxtel $ in Thousands	Aug. 28, 2020 USD ($)
Business Acquisition [Line Items]
Finite-life intangible assets	$ 13,600
Completed technology
Business Acquisition [Line Items]
Useful Life	12 years
Finite-life intangible assets	$ 13,100
Customer relationships
Business Acquisition [Line Items]
Useful Life	6 years
Finite-life intangible assets	$ 300
Trademarks
Business Acquisition [Line Items]
Useful Life	5 years
Finite-life intangible assets	$ 200

Revenue from Contract with Customers - Net Sales by Core End Market and Application (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 164,449	$ 159,802	$ 416,099	$ 475,485
Automotive
Disaggregation of Revenue [Line Items]
Total net sales	113,902	99,074	279,759	289,681
Industrial
Disaggregation of Revenue [Line Items]
Total net sales	23,654	21,358	65,710	56,095
Other
Disaggregation of Revenue [Line Items]
Total net sales	26,893	15,070	70,630	53,399
Wafer foundry products
Disaggregation of Revenue [Line Items]
Total net sales	0	16,634	0	49,622
Distribution of Sanken products
Disaggregation of Revenue [Line Items]
Total net sales	$ 0	$ 7,666	$ 0	$ 26,688

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9031-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9038-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130543-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130545-203045

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Revenue from Contract with Customers - Net Sales by Product (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 164,449	$ 159,802	$ 416,099	$ 475,485
Power integrated circuits (“PIC”)
Disaggregation of Revenue [Line Items]
Total net sales	54,406	43,665	146,276	123,900
Magnetic sensors (“MS”)
Disaggregation of Revenue [Line Items]
Total net sales	109,457	91,837	268,956	275,275
Photonics
Disaggregation of Revenue [Line Items]
Total net sales	586	0	867	0
Wafer foundry products
Disaggregation of Revenue [Line Items]
Total net sales	0	16,634	0	49,622
Distribution of Sanken products
Disaggregation of Revenue [Line Items]
Total net sales	$ 0	$ 7,666	$ 0	$ 26,688

- Definition

+ References

+ Details

Revenue from Contract with Customers - Net Sales by Geography (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 164,449	$ 159,802	$ 416,099	$ 475,485
United States
Disaggregation of Revenue [Line Items]
Total net sales	23,934	27,498	57,892	86,746
Other Americas
Disaggregation of Revenue [Line Items]
Total net sales	5,620	4,722	10,797	15,930
Europe
Disaggregation of Revenue [Line Items]
Total net sales	28,239	24,341	70,459	76,622
Japan
Disaggregation of Revenue [Line Items]
Total net sales	26,439	46,010	72,570	131,950
Greater China
Disaggregation of Revenue [Line Items]
Total net sales	46,172	35,284	116,178	95,244
South Korea
Disaggregation of Revenue [Line Items]
Total net sales	17,606	14,119	43,733	41,413
Other Asia
Disaggregation of Revenue [Line Items]
Total net sales	$ 16,439	$ 7,828	$ 44,470	$ 27,580

- Definition

+ References

+ Details

Revenue from Contract with Customers - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Mar. 27, 2020
Revenue from Contract with Customer [Abstract]
Trade accounts receivable, returns, credits issued, and price protection adjustments, current	$ 16,574		$ 17,473
Trade accounts receivable, returns, credits issued, and price protection adjustments expense (credit)	$ 899	$ 815

Fair Value Measurements - Assets And Liabilities Measured At Fair Value (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Assets:
Total assets	$ 22,840	$ 51,722
Liabilities:
Contingent consideration	7,800
Total liabilities	7,800
Level 1
Assets:
Total assets	22,840	51,722
Liabilities:
Contingent consideration	0
Total liabilities	0
Level 2
Assets:
Total assets	0	0
Liabilities:
Contingent consideration	0
Total liabilities	0
Level 3
Assets:
Total assets	0	0
Liabilities:
Contingent consideration	7,800
Total liabilities	7,800
Money Market Funds
Assets:
Cash and cash equivalents, fair value disclosure	16,320	46,337
Restricted cash and restricted cash equivalents, fair value disclosure	6,520	5,385
Money Market Funds \| Level 1
Assets:
Cash and cash equivalents, fair value disclosure	16,320	46,337
Restricted cash and restricted cash equivalents, fair value disclosure	6,520	5,385
Money Market Funds \| Level 2
Assets:
Cash and cash equivalents, fair value disclosure	0	0
Restricted cash and restricted cash equivalents, fair value disclosure	0	0
Money Market Funds \| Level 3
Assets:
Cash and cash equivalents, fair value disclosure	0	0
Restricted cash and restricted cash equivalents, fair value disclosure	$ 0	$ 0

Fair Value Measurements - Change in Fair Value of Level 3 Contingent Consideration (Details) - Fair Value, Recurring - Level 3 $ in Thousands	9 Months Ended
	Dec. 25, 2020 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0
Additions during the year	7,800
Ending balance	$ 7,800

Trade Accounts Receivable, net - Summary of Trade Accounts Receivable, net (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020	Dec. 27, 2019	Mar. 29, 2019
Receivables [Abstract]
Trade accounts receivable	$ 103,687	$ 107,223
Less:
Allowance for doubtful accounts	(138)	(288)	$ (237)	$ (412)
Returns and sales allowances	(16,437)	(17,185)	$ (16,967)	$ (17,607)
Related party trade accounts receivable	(19,778)	(30,293)
Trade accounts receivable, net	$ 67,334	$ 59,457

Trade Accounts Receivable, net - Schedule of Changes in Allowance For Doubtful Accounts and Sales Returns and Sales Allowances (Details) - USD ($) $ in Thousands	9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019
Allowance for Doubtful Accounts
Balance at the beginning of the period	$ 288	$ 412
Charged to costs and expenses or revenue	(150)	(175)
Write-offs, net of recoveries	0	0
Balance at the end of the period	138	237
Returns and Sales Allowances
Balance at the beginning of the period	17,185	17,607
Charged to costs and expenses or revenue	103,660	91,690
Write-offs, net of recoveries	(104,408)	(92,330)
Balance at the end of the period	16,437	16,967
Total
Balance at the beginning of the period	17,473	18,019
Charged to costs and expenses or revenue	103,510	91,515
Write-offs, net of recoveries	(104,408)	(92,330)
Balance at the end of the period	$ 16,575	$ 17,204

Inventories (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Inventories (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019	Aug. 28, 2020	Mar. 27, 2020
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 8,689		$ 8,689			$ 12,411
Work in process	57,477		57,477			87,606
Finished goods	24,451		24,451			24,659
Finished goods – consigned	3,404		3,404			2,551
Total	94,021		94,021			$ 127,227
Inventory [Line Items]
Recorded inventory provisions	885	$ 1,008	2,958	$ 2,538
Voxtel
Inventory [Line Items]
Acquired inventory	$ 1,245		$ 1,245		$ 3,120

Property, Plant and Equipment, net - Schedule of PPE (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Property, Plant and Equipment [Line Items]
Total	$ 621,759	$ 907,951
Less accumulated depreciation	(407,387)	(575,621)
Total	214,372	332,330
Land
Property, Plant and Equipment [Line Items]
Total	23,829	27,898
Buildings, building improvements and leasehold improvements
Property, Plant and Equipment [Line Items]
Total	91,535	150,402
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total	488,796	694,215
Office equipment
Property, Plant and Equipment [Line Items]
Total	6,643	7,517
Construction in progress
Property, Plant and Equipment [Line Items]
Total	$ 10,956	$ 27,919

Property, Plant and Equipment, net - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 11,255	$ 15,677	$ 33,861	$ 46,247
Prepaid tooling costs
Property, Plant and Equipment [Line Items]
Amortization expense	$ 18	$ 32	$ 54	$ 94

Property, Plant and Equipment, net - Schedule of Long Lived Assets (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	$ 215,710	$ 333,646
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	35,894	152,536
Philippines
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	136,284	106,618
Thailand
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	34,226	62,380
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	$ 9,306	$ 12,112

Goodwill and Intangible Assets - Summary of Changes in Carrying Amount of Goodwill (Details) $ in Thousands	9 Months Ended
	Dec. 25, 2020 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 1,285
Goodwill arising from Acquisition	18,803
Currency translation	161
Ending balance	$ 20,249

Goodwill and Intangible Assets - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 26, 2020	Dec. 25, 2020	Mar. 27, 2020
Finite-Lived Intangible Assets [Line Items]
Gross		$ 56,037	$ 36,867
Accumulated Amortization		19,617	16,909
Net Carrying Amount		36,420	19,958
Patents
Finite-Lived Intangible Assets [Line Items]
Gross		31,852	29,115
Accumulated Amortization		11,661	9,834
Net Carrying Amount		$ 20,191	19,281
Weighted- Average Lives	10 years	10 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross		$ 6,193	5,462
Accumulated Amortization		5,823	5,335
Net Carrying Amount		$ 370	127
Weighted- Average Lives	9 years	9 years
Process technology
Finite-Lived Intangible Assets [Line Items]
Gross		$ 17,150	1,650
Accumulated Amortization		2,028	1,650
Net Carrying Amount		$ 15,122	0
Weighted- Average Lives		12 years
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross		$ 810	608
Accumulated Amortization		73	58
Net Carrying Amount		$ 737	550
Weighted- Average Lives		5 years
Other
Finite-Lived Intangible Assets [Line Items]
Gross		$ 32	32
Accumulated Amortization		32	32
Net Carrying Amount		$ 0	$ 0

Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
	Aug. 28, 2020	Dec. 25, 2020	Jun. 26, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019	Mar. 27, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 20,249			$ 20,249		$ 1,285
Intangible assets amortization expense		$ 926		$ 422	$ 2,310	$ 1,267
Patents
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life			10 years		10 years
Voxtel
Acquired Finite-Lived Intangible Assets [Line Items]
Preliminary purchase price	$ 35,081
Goodwill	18,803
Finite-lived intangible assets	13,600
Indefinite-lived intangible assets acquired	$ 2,400

Goodwill and Intangible Assets - Future Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2021	$ 850
2022	3,293
2023	3,139
2024	3,003
2025	2,709
Thereafter	23,426
Net Carrying Amount	$ 36,420	$ 19,958

Other Assets, net (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
VAT receivables long-term, net	$ 6,662	$ 3,039
Deposits	2,414	2,399
Prepaid contracts long-term	1,478	1,282
Other	1,928	2,090
Total	$ 12,482	$ 8,810

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Payables and Accruals [Abstract]
Accrued management incentive (LTCIP)	$ 94	$ 11,488
Accrued management incentive (non-LTCIP)	14,143	6,273
Accrued salaries and wages	18,603	12,069
Base acquisition purchase price due	17,244	0
Accrued vacation	5,534	7,146
Accrued severance	2,643	6,065
Accrued professional fees	1,057	4,036
Accrued income taxes	1,803	3,408
Accrued utilities	628	1,114
Other current liabilities	5,030	5,256
Total	$ 66,779	$ 56,855

Management Long-Term Incentive Plan (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Nov. 02, 2020	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Stock-based compensation		$ 45,876	$ 303	$ 46,901	$ 1,051
Current Liabilities
Balance at the beginning of the period				11,488
Balance at the end of the period		94		94
Long-Term Liabilities
Balance at the beginning of the period				2,439
Balance at the end of the period		194		194
Restricted Stock Units (RSUs)
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Stock-based compensation	$ 1,028	2,131		$ 2,131
Grants in period (in shares)				1,426,944
Grant date fair value (in dollars per share)				$ 14.04
RSU Conversion Program \| Restricted Stock Units (RSUs)
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Grant date fair value (in dollars per share)	$ 14.00
LTIP
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Rolling performance period				3 years
Current Liabilities
Balance at the beginning of the period				$ 11,488
Reclassification				1,004
Payments				(11,096)
RSU conversion				(640)
Removal due to divestiture				(378)
Accruals				(284)
Balance at the end of the period		94		94
Long-Term Liabilities
Balance at the beginning of the period				2,439
Reclassification				(1,004)
Payments				0
RSU conversion				0
Removal due to divestiture				(398)
Accruals				(843)
Balance at the end of the period		$ 194		$ 194
LTIP \| RSU Conversion Program
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Stock-based compensation	$ 607
LTIP \| RSU Conversion Program \| Restricted Stock Units (RSUs)
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Grants in period (in shares)	602,490
TRIP \| RSU Conversion Program
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Stock-based compensation	$ 421
TRIP \| RSU Conversion Program \| Restricted Stock Units (RSUs)
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Grants in period (in shares)	348,911

Debt and Other Borrowings - Summary of Components of Debt (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Debt Instrument [Line Items]
Total Debt	$ 25,000	$ 43,000
Less debt payable within one year	0	43,000
Debt payable after one year	25,000	0
Line of Credit \| Senior Secured Term Loan
Debt Instrument [Line Items]
Total Debt	25,000	0
Line of Credit \| Unsecured Revolving Credit Facilities
Debt Instrument [Line Items]
Total Debt	$ 0	$ 43,000

Debt and Other Borrowings - Schedule of Principal Maturities of Debt Obligations (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Long-term Debt, Fiscal Year Maturity [Abstract]
Remainder of 2021	$ 0
2022	0
2023	0
2024	0
2025	0
Thereafter	25,000
Total Debt	$ 25,000	$ 43,000

Debt and Other Borrowings - Senior Secured Credit Facilities (Details)			3 Months Ended		9 Months Ended
	Nov. 25, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)
Line of Credit Facility [Line Items]
Loss on debt extinguishment			$ 9,055,000	$ 0	$ 9,055,000	$ 0
Senior Secured Term Loan \| Credit Suisse AG, Cayman Islands Branch
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 325,000,000
Repayments of line-of-credit agreement	$ 300,000,000
Deferred financing costs		9,374,000
Loss on debt extinguishment					$ 9,055,000
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd
Line of Credit Facility [Line Items]
Maximum borrowing capacity		50,000,000
Interest rate at period end			4.50%		4.50%
Outstanding balance			$ 0		$ 0
Deferred financing costs		$ 300,000
Unamortized deferred financing costs			$ 254,000		$ 254,000
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Interest rate floor		0.005
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd \| London Interbank Offered Rate (LIBOR) \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate		3.75%
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd \| London Interbank Offered Rate (LIBOR) \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate		4.00%
Line of Credit \| Mizuho Bank, Ltd
Line of Credit Facility [Line Items]
Repayments of line-of-credit agreement		$ 25,000,000
Line of Credit \| Bank Of Mitsubishi UFJ
Line of Credit Facility [Line Items]
Repayments of line-of-credit agreement		$ 8,000,000

Debt and Other Borrowings - Unsecured Revolving Credit Facilities (Details)				1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended
	Mar. 18, 2020 USD ($)	Jan. 22, 2019 USD ($)	Mar. 27, 2006 USD ($)	Mar. 31, 2020 USD ($)	Jun. 26, 2020 USD ($)	Mar. 27, 2020 USD ($)	Dec. 25, 2020 USD ($)	Mar. 27, 2020 USD ($)	Nov. 26, 2019 PHP (₱)	Nov. 20, 2019 PHP (₱)
COVID-19
Line of Credit Facility [Line Items]
Proceeds from lines of credit				$ 43,000,000		$ 43,000,000
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring January 22, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 25,000
Proceeds from lines of credit								$ 25,000,000
Outstanding balance						$ 25,000,000		$ 25,000,000
Interest rate at period end						1.70%		1.70%
Collateral, secured period							1 year
Collateral fees, amount							$ 25,000
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring January 22, 2021 \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.40%
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Due at Various Times During Fiscal Year 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 10,000
Proceeds from lines of credit					$ 10,000,000
Outstanding balance						$ 10,000,000		$ 10,000,000
Interest rate at period end						2.50%		2.50%
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Due at Various Times During Fiscal Year 2021 \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate			1.00%
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Maturing June 18, 2020 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity					$ 8,000,000
Proceeds from lines of credit	$ 8,000,000
Outstanding balance						$ 8,000,000		$ 8,000,000
Interest rate at period end						1.90%		1.90%
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring August 31, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity							1,247,000		₱ 60,000,000
Outstanding balance						$ 0	0	$ 0
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring June 30, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity							1,559,000			₱ 75,000,000
Outstanding balance						$ 0	$ 0	$ 0

Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Other Liabilities Disclosure [Abstract]
Accrued management incentive (LTCIP)	$ 194	$ 2,439
Accrued management incentive (non-LTCIP)	318	2,304
Accrued retirement	9,516	8,005
Accrued contingent consideration	7,800	0
Provision for uncertain tax positions (net)	2,758	2,855
Other	275	275
Total	$ 20,861	$ 15,878

Retirement Plans - Schedule of Expense Related to Defined Benefit Plan (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 296	$ 242	$ 843	$ 717
Interest cost	166	169	474	503
Expected return on plan assets	(79)	(83)	(231)	(247)
Amortization of net transition asset	0	(4)	0	(10)
Amortization of prior service cost	2	2	6	6
Actuarial loss	47	24	126	72
Net periodic pension expense	$ 432	$ 350	$ 1,218	$ 1,041

Retirement Plans - Fair Value of Entity's Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	Dec. 25, 2020	Mar. 27, 2020
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	$ 7,089	$ 5,579
Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	3,031	2,467
Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	2,349	1,992
Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,709	1,120
Government securities
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,826	1,260
Government securities \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,826	1,260
Government securities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Government securities \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Unit investment trust fund
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,155	897
Unit investment trust fund \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Unit investment trust fund \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,155	897
Unit investment trust fund \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Loans
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	562	756
Loans \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Loans \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Loans \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	562	756
Bonds
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,193	1,094
Bonds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Bonds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,193	1,094
Bonds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	0	0
Stocks and other investments
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	2,353	1,572
Stocks and other investments \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,205	1,207
Stocks and other investments \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1	1
Stocks and other investments \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	$ 1,147	$ 364

Retirement Plans - Schedule of Changes in Fair Value of Level 3 Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	$ 5,579
Ending balance	7,089
Loans
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	756
Ending balance	562
Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	1,120
Ending balance	1,709
Level 3 \| Loans
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	756
Additions during the year	207
Redemptions during the year	(440)
Revaluation of equity securities	0
Change in foreign currency exchange rates	39
Ending balance	$ 562
Level 3 \| Stocks
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance		$ 364
Additions during the year		0
Redemptions during the year		0
Revaluation of equity securities		753
Change in foreign currency exchange rates		30
Ending balance		$ 1,147

Retirement Plans - Narrative (Details) £ in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)	Dec. 25, 2020 GBP (£)	Mar. 27, 2020 USD ($)	Mar. 27, 2020 GBP (£)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 249	$ 235	$ 736	$ 698
Expected contributions in current fiscal year	943		$ 943
Other Defined Benefit Plan \| Pension Promise
Defined Benefit Plan Disclosure [Line Items]
Retirement age			65 years
Other assets, net	1,112		$ 1,112		£ 827	$ 975	£ 866
Accrued retirement, other long-term liabilities	1,112		$ 1,112		£ 827	$ 975	£ 866
Defined Contribution Plan
Defined Benefit Plan Disclosure [Line Items]
Maximum employee contribution			50.00%
Employer matching contribution			100.00%
Maximum employer contribution			5.00%
Total contributions	1,112	833	$ 3,181	2,840
Defined Contribution Plan \| AME Plan
Defined Benefit Plan Disclosure [Line Items]
Total contributions	$ 207	201	$ 592	560
Defined Contribution Plan \| 401(K) Plan
Defined Benefit Plan Disclosure [Line Items]
Maximum employee contribution			35.00%
Employer matching contribution			100.00%
Maximum employer contribution			5.00%
Total contributions		$ 376		$ 1,310
Vesting percentage			100.00%
Safe Harbor Provision, employer contribution			0.03

Commitment and Contingencies (Details) - USD ($)	Dec. 25, 2020	Mar. 27, 2020
Loss Contingencies [Line Items]
Indemnification accruals	$ 0	$ 0
Environmental accruals	$ 0	$ 0
Minimum
Loss Contingencies [Line Items]
Operating lease agreement term	1 year
Maximum
Loss Contingencies [Line Items]
Operating lease agreement term	7 years

Net (Loss) Income per Share - Narrative (Details)		3 Months Ended		9 Months Ended
Net (Loss) Income per Share - Narrative (Details)	Nov. 02, 2020 shares	Dec. 25, 2020 shares	Dec. 27, 2019 shares	Dec. 25, 2020 shares	Dec. 27, 2019 shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issued upon conversion, including shares withheld for tax withholding obligation (in shares)	166,500,000
Basic weighted average common shares (in shares)		124,363,078	10,000,000	48,121,026	10,000,000
Diluted weighted average common shares (in shares)		124,363,078	10,000,000	171,638,787	10,000,000
Antidilutive securities excluded from computation of net loss per share (in shares)		57,553,282
Common Stock, Class A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion rate	15.822
Shares returned for tax payments made on behalf of holders of common stock (in shares)	2,066,508
Common Stock, Class A \| Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Priority dividend rate				8.00%
Annualized return on capital, triggering percent, remaining distributions split between Class A and Class L shareholders				8.00%
Common Stock, Class L
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion rate	13.010
Shares returned for tax payments made on behalf of holders of common stock (in shares)	1,766

Net (Loss) Income per Share - Schedule of Computation of Net Income per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Earnings Per Share [Abstract]
Net (loss) income attributable to Allegro MicroSystems, Inc.	$ (5,095)	$ 8,926	$ 9,309	$ 23,675
Net (loss) income attributable to common stockholders, basic	(5,060)	8,958	9,412	23,776
Net (loss) income attributable to common stockholders, diluted	$ (5,060)	$ 8,958	$ 9,412	$ 23,776
Basic weighted average common shares (in shares)	124,363,078	10,000,000	48,121,026	10,000,000
Dilutive effect of common stock equivalents (in shares)	0	0	123,517,761	0
Diluted weighted average common shares (in shares)	124,363,078	10,000,000	171,638,787	10,000,000
Basic net (loss) income attributable to Allegro MicroSystems, Inc. per share (in dollars per share)	$ (0.04)	$ 0.89	$ 0.19	$ 2.37
Basic net (loss) income attributable to common stockholders per share (in dollars per share)	(0.04)	0.90	0.20	2.38
Diluted net (loss) income attributable to Allegro MicroSystems, Inc. per share (in dollars per share)	(0.04)	0.89	0.05	2.37
Diluted net (loss) income attributable to common stockholders per share (in dollars per share)	$ (0.04)	$ 0.90	$ 0.05	$ 2.38

Net (Loss) Income per Share - Schedule of Issuable Weighted Average Share Information (Details) - shares	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive effect of common stock equivalents (in shares)	57,553,282	0	123,517,761	0
Common Class A and Common Class L
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive effect of common stock equivalents (in shares)	56,752,747	0	123,250,916	0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive effect of common stock equivalents (in shares)	377,767	0	125,922	0
Performance Stock Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive effect of common stock equivalents (in shares)	422,768	0	140,923	0

Common Stock and Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended		7 Months Ended	9 Months Ended
	Nov. 02, 2020 USD ($) $ / shares shares	Oct. 02, 2020 USD ($) shares	Oct. 31, 2017 USD ($) class $ / shares shares	Dec. 25, 2020 USD ($) $ / shares shares	Dec. 27, 2019 USD ($) shares	Nov. 01, 2020 $ / shares shares	Dec. 25, 2020 USD ($) $ / shares shares	Dec. 27, 2019 USD ($) $ / shares shares	Sep. 25, 2020 shares	Mar. 27, 2020 $ / shares shares	Sep. 27, 2019 shares	Mar. 29, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of classes of stock \| class			2
Common stock, shares authorized (in shares)				1,000,000,000			1,000,000,000			0
Common stock, par value (in dollars per share) \| $ / shares				$ 0.01			$ 0.01			$ 0.01
Stock repurchased during period, aggregate purchase price \| $				$ 27,707			$ 27,707
Shares issued upon conversion, including shares withheld for tax withholding obligation (in shares)	166,500,000
Common stock, shares outstanding (in shares)				189,431,726			189,431,726			0
Shares issued upon conversion (in shares)	164,431,726
Weighted average conversion price (in dollars per share) \| $ / shares	$ 14.00
Stock-based compensation \| $				$ 45,876	$ 303		$ 46,901	$ 1,051
IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued in transaction (in shares)	28,750,000
Offering price (in dollars per share) \| $ / shares	$ 14.00
Net proceeds \| $	$ 321,425
Underwriting discounts \| $	20,125
Estimated offering costs \| $	$ 8,450
IPO \| Allegro Microsystems, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued in transaction (in shares)	25,000,000
IPO - Selling Shareholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued in transaction (in shares)	3,750,000
LTIP \| RSU Conversion Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation \| $	$ 607
TRIP \| RSU Conversion Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation \| $	$ 421
Shares of Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon conversion (in shares)	163,971,977
Shares of Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon conversion (in shares)	459,749
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)							1,426,944
Stock-based compensation \| $	$ 1,028			2,131			$ 2,131
Grant date fair value (in dollars per share) \| $ / shares							$ 14.04
Stock-based compensation expense not yet recorded \| $				17,496			$ 17,496
Stock-based compensation expense not yet recorded, period for recognition							1 year 8 months 26 days
Vested during period (in shares)							376
Restricted Stock Units (RSUs) \| Share-based Payment Arrangement, Nonemployee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)							54,644
Restricted Stock Units (RSUs) \| RSU Conversion Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value (in dollars per share) \| $ / shares	$ 14.00
Restricted Stock Units (RSUs) \| LTIP \| RSU Conversion Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	602,490
Restricted Stock Units (RSUs) \| TRIP \| RSU Conversion Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	348,911
Performance Stock Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)							650,302
Stock-based compensation \| $				467			$ 467
Grant date fair value (in dollars per share) \| $ / shares							$ 15.05
Stock-based compensation expense not yet recorded \| $				$ 9,320			$ 9,320
Stock-based compensation expense not yet recorded, period for recognition							2 years 10 months 24 days
Performance period							3 years
Vested during period (in shares)							0
Intrinsic value, vested \| $							$ 16,121
Performance Stock Units (PSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant percentage of target shares granted maximum				0			0
Inclusion percentage of target goals				100.00%			100.00%
Performance Stock Units (PSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant percentage of target shares granted maximum				2			2
Inclusion percentage of target goals				200.00%			200.00%
Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)							459,749
Stock-based compensation \| $				$ 73			$ 73
Grant date fair value (in dollars per share) \| $ / shares							$ 14.00
Vested during period (in shares)							37,161
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common shares (in shares)				25,000,000			25,000,000
Stock repurchased during period (in shares)				2,068,274			2,068,274
Stock repurchased during period, aggregate purchase price \| $				$ 21			$ 21
Common stock, shares outstanding (in shares)				189,431,726			189,431,726		0	0
Common Stock, Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued in transaction (in shares)			2,880,000
Net proceeds \| $			$ 291
Estimated offering costs \| $			$ 9,260
Common stock, shares authorized (in shares)			12,500,000	0			0			12,500,000
Common stock, par value (in dollars per share) \| $ / shares			$ 0.01	$ 0.01			$ 0.01			$ 0.01
Issuance of common shares (in shares)			6,720,000
Priority dividend, percentage			0.08
Grants in period (in shares)			400,000
Vesting period			60 months
Conversion rate	15.822
Shares returned for tax payments made on behalf of holders of common stock (in shares)	2,066,508
Common stock, shares outstanding (in shares)				0			0			10,000,000
Shares issued upon conversion (in shares)	156,155,403
Stock-based compensation \| $	$ 40,440
Common Stock, Class A \| Shares of Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon conversion (in shares)	156,155,403
Common Stock, Class A \| Shares of Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon conversion (in shares)	0
Common Stock, Class A \| OEP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncontrolling interest ownership percentage			28.80%
Common Stock, Class A \| If Initial Public Offering or Change in Control Occurs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting cost \| $			$ 40,440
Accelerated vesting, number (in shares)			400,000
Accelerated vesting, share price (in dollars per share) \| $ / shares			$ 101.10
Common Stock, Class A \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares outstanding (in shares)				0	10,000,000		0	10,000,000	10,000,000	10,000,000	10,000,000	10,000,000
Common Stock, Class L
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized (in shares)			1,000,000	0			0			1,000,000
Common stock, par value (in dollars per share) \| $ / shares			$ 0.01	$ 0.01			$ 0.01			$ 0.01
Grants in period (in shares)			597,400
Vesting period			4 years
Accelerated vesting, percentage	0.25
Stock repurchased during period (in shares)		1,997
Stock repurchased during period, aggregate purchase price \| $		$ 408
Conversion rate	13.010
Shares returned for tax payments made on behalf of holders of common stock (in shares)	1,766
Outstanding loan amounts extinguished \| $		$ 753
Common stock, shares outstanding (in shares)				0		638,298	0			622,470
Common stock, shares outstanding, weighted average price per share (in dollars per share) \| $ / shares						$ 11.99
Shares issued upon conversion (in shares)	8,276,323
Stock-based compensation \| $	$ 1,610			$ 144			$ 1,169
Common Stock, Class L \| Shares of Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon conversion (in shares)	7,816,574
Common Stock, Class L \| Shares of Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon conversion (in shares)	459,749
Common Stock, Class L \| If Initial Public Offering Occurs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting, percentage			0.25
Accelerated vesting, minimum percentage of awards unvested			0.25
Common Stock, Class L \| If a Change in Control Occurs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting, percentage			1
Common Stock, Class L \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common shares (in shares)						17,203	15,828	30,300
Shares issued during period, weighted average price per share (in dollars per share) \| $ / shares						$ 33.83		$ 26.93
Stock repurchased during period (in shares)				1,997			1,997
Common stock, shares outstanding (in shares)				0	607,620		0	607,620	638,298	622,470	607,620	607,620

Common Stock and Stock-Based Compensation - Schedule of Stock Issued in Common Stock Conversion (Details)	Nov. 02, 2020 shares
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	164,431,726
Common Stock, Class A
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	156,155,403
Common Stock, Class L
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	8,276,323
Shares of Common Stock
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	163,971,977
Shares of Common Stock \| Common Stock, Class A
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	156,155,403
Shares of Common Stock \| Common Stock, Class L
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	7,816,574
Shares of Unvested Restricted Common Stock
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	459,749
Shares of Unvested Restricted Common Stock \| Common Stock, Class A
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	0
Shares of Unvested Restricted Common Stock \| Common Stock, Class L
Conversion of Stock [Line Items]
Shares issued upon conversion (in shares)	459,749

Common Stock and Stock-Based Compensation - Schedule of Restricted Stock Units Activity (Details) - Restricted Stock Units (RSUs) $ / shares in Units, $ in Thousands	9 Months Ended
	Dec. 25, 2020 USD ($) $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	0
Granted (in shares) \| shares	1,426,944
Vested (in shares) \| shares	(376)
Cancelled (in shares) \| shares	(28,920)
Ending balance (in shares) \| shares	1,397,648
Weighted-Average Grant-Date Fair Value
Beginning balance (in dollars per share) \| $ / shares	$ 0
Granted (in dollars per share) \| $ / shares	14.04
Vested (in dollars per share) \| $ / shares	14.00
Cancelled (in dollars per share) \| $ / shares	14.00
Ending balance (in dollars per share) \| $ / shares	$ 14.04
Weighted-Average Remaining Contractual Life	1 year 8 months 26 days
Aggregate Intrinsic Value \| $	$ 34,648

Common Stock and Stock-Based Compensation - Schedule of Performance Units Fair Value Assumptions (Details) - Performance Stock Units (PSUs)	9 Months Ended
	Dec. 25, 2020 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance term	2 years 5 months 1 day
Volatility	49.90%
Risk-free rate of return	0.17%
Dividend yield	0.00%
Weighted-average fair value per share (in dollars per share)	$ 14.00

Common Stock and Stock-Based Compensation - Summary of Performance Stock Units Activity (Details) - Performance Stock Units (PSUs) $ / shares in Units, $ in Thousands	9 Months Ended
	Dec. 25, 2020 USD ($) $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	0
Granted (in shares) \| shares	650,302
Vested (in shares) \| shares	0
Cancelled (in shares) \| shares	0
Ending balance (in shares) \| shares	650,302
Weighted-Average Grant-Date Fair Value
Beginning balance (in dollars per share) \| $ / shares	$ 0
Granted (in dollars per share) \| $ / shares	15.05
Vested (in dollars per share) \| $ / shares	0
Cancelled (in dollars per share) \| $ / shares	0
Ending balance (in dollars per share) \| $ / shares	$ 15.05
Weighted-Average Remaining Contractual Life	2 years 10 months 24 days
Aggregate Intrinsic Value \| $	$ 16,121

Common Stock and Stock-Based Compensation - Summary of Unvested Restricted Common Stock Activity (Details) - Restricted Common Stock $ / shares in Units, $ in Thousands	9 Months Ended
	Dec. 25, 2020 USD ($) $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	0
Granted (in shares) \| shares	459,749
Vested (in shares) \| shares	(37,161)
Cancelled (in shares) \| shares	0
Ending balance (in shares) \| shares	422,588
Weighted-Average Grant-Date Fair Value
Beginning balance (in dollars per share) \| $ / shares	$ 0
Granted (in dollars per share) \| $ / shares	14.00
Vested (in dollars per share) \| $ / shares	14.00
Cancelled (in dollars per share) \| $ / shares	0
Ending balance (in dollars per share) \| $ / shares	$ 14.00
Weighted-Average Remaining Contractual Life	2 years 3 days
Aggregate Intrinsic Value \| $	$ 10,476

Common Stock and Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020	Dec. 27, 2019	Dec. 25, 2020	Dec. 27, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	$ 45,876	$ 303	$ 46,901	$ 1,051
Cost of sales
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	4,694	47	4,844	137
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	2,984	20	3,037	65
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	$ 38,198	$ 236	$ 39,020	$ 849

Income Taxes - Schedule of Tax Provision (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)
Income Tax Disclosure [Abstract]
Operating taxes	$ (12,169)	$ 1,703	$ (9,764)	$ 5,980
Discrete tax items	(18,354)	(161)	(18,149)	5,730
(Benefit) provision for income taxes	$ (30,523)	$ 1,542	$ (27,913)	$ 11,710
Annual operating tax rate	0.342	0.162	0.528	0.169
Effective tax rate	85.80%	14.70%	150.90%	33.00%

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Nov. 02, 2020	Dec. 25, 2020	Dec. 27, 2019	Jun. 28, 2019	Dec. 25, 2020	Dec. 27, 2019
Income Tax Contingency [Line Items]
(Benefit) provision for income taxes		$ (30,523)	$ 1,542		$ (27,913)	$ 11,710
Effective tax rate		85.80%	14.70%		150.90%	33.00%
(Loss) income before income tax (benefit) provision		$ (35,583)	$ 10,500		$ (18,501)	$ 35,486
Stock-based compensation		45,876	303		46,901	1,051
Discrete tax items		$ (18,354)	$ (161)		$ (18,149)	$ 5,730
Settlement of IRS transfer pricing audits				$ 5,500
Common Stock, Class A
Income Tax Contingency [Line Items]
Stock-based compensation	$ 40,440

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Related Party Transactions (Details)				1 Months Ended	3 Months Ended			9 Months Ended
Related Party Transactions (Details)	Oct. 14, 2020 USD ($)	Oct. 02, 2020 USD ($) shares	Mar. 28, 2020 USD ($)	Sep. 30, 2017 USD ($) shares	Dec. 25, 2020 USD ($)	Jun. 26, 2020	Dec. 27, 2019 USD ($)	Dec. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)	Mar. 27, 2020 USD ($) notesPayable lineOfCredit	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	May 31, 2018 USD ($)
Related Party Transaction [Line Items]
Total net sales					$ 164,449,000		$ 159,802,000	$ 416,099,000	$ 475,485,000
Trade accounts receivable from related party					19,778,000			19,778,000		$ 30,293,000
Amounts due to related party					2,078,000			2,078,000		4,494,000
Related party notes payable, less current portion					0			0		17,700,000
Current portion of related party debt					0			0		25,000,000
Noncash or part noncash divestiture, amount of consideration received								0	0
Trade accounts receivable, net					67,334,000			67,334,000		59,457,000
Stock repurchased during period, aggregate purchase price					27,707,000			27,707,000
Common Stock, Class L
Related Party Transaction [Line Items]
Stock repurchased during period (in shares) \| shares		1,997
Stock repurchased during period, aggregate purchase price		$ 408,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL
Related Party Transaction [Line Items]
Noncash or part noncash divestiture, amount of consideration received			$ 42,700,000
Noncash or part noncash divestiture, amount of consideration transferred			$ 15,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL \| Sanken \| PSL
Related Party Transaction [Line Items]
Ownership percentage by majority shareholder			70.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL \| PSL
Related Party Transaction [Line Items]
Stated interest rate			2.70%
Interest paid	$ 762,000
Repayments of related party notes receivable	51,377,000
Related party debt			$ 66,377,000
Note receivable from related party					51,377,000			51,377,000
Interest payable	$ 762,000				762,000			762,000
Related Party Revenue
Related Party Transaction [Line Items]
Total net sales					26,439,000		16,535,000	72,570,000	49,327,000
Distribution of Sanken products
Related Party Transaction [Line Items]
Total net sales					0		7,666,000	0	26,688,000
Sanken
Related Party Transaction [Line Items]
Trade accounts receivable from related party					17,250,000			17,250,000		30,293,000
Other accounts receivable from related party					374,000			374,000		558,000
Purchases from related party							7,356,000		23,835,000
Amounts due to related party										$ 4,494,000
Reimbursement of development costs					0		360,000	0	1,080,000
Promissory notes outstanding											$ 30,000,000
Stated interest rate											2.52%
Interest income									55,000
Number of notes payable \| notesPayable										3
Related party notes payable, less current portion										$ 17,700,000
Number of line-of-credit agreements \| lineOfCredit										2
Current portion of related party debt										$ 25,000,000
Basis spread on variable rate						1.00%
Interest expense							334,000		1,129,000
Interest paid							81,000		835,000
Sanken \| Related Party Revenue
Related Party Transaction [Line Items]
Total net sales					26,439,000		16,535,000	72,570,000	49,327,000
Sanken \| Distribution of Sanken products
Related Party Transaction [Line Items]
Total net sales							7,666,000		26,688,000
PSL
Related Party Transaction [Line Items]
Trade accounts receivable from related party			3,368,000		2,528,000			2,528,000
Purchases from related party					11,558,000			33,448,000
Amounts due to related party					2,078,000			2,078,000
Reduction of intercompany balances					1,157,000			1,198,000
PSL \| Discrete Technology Development Agreement
Related Party Transaction [Line Items]
Fees paid					0		0	0	0
PSL \| IC Technology Development Agreement
Related Party Transaction [Line Items]
Fees paid					300,000			900,000
Fees received					300,000		$ 900,000	300,000	900,000
PSL \| Price Support Payment
Related Party Transaction [Line Items]
Purchases from related party					1,500,000			5,000,000
PSL \| Eliminations
Related Party Transaction [Line Items]
Accounts payable to related party			1,198,000
Trade accounts receivable, net			$ 3,368,000
PSL \| PSL
Related Party Transaction [Line Items]
Repayments of related party notes receivable								3,368,000
Director
Related Party Transaction [Line Items]
Fees paid								262,000	$ 270,000
Monthly fee payable												$ 19,000	$ 30,000
Signing fee				$ 54,000
Severance payment if terminated				$ 180,000
Accelerated vesting, acceleration period				6 months
Director \| Common Stock, Class L
Related Party Transaction [Line Items]
Shares granted (in shares) \| shares				12,000,000
Directors and executive officers
Related Party Transaction [Line Items]
Related party debt					$ 0			$ 0		$ 506,000