0000866291-20-000011 | 10-Q | XBRL Viewer

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Cover Page - shares	6 Months Ended
Cover Page - shares	Sep. 25, 2020	Nov. 16, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 25, 2020
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	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		189,431,766
Entity Central Index Key	0000866291
Amendment Flag	false
Current Fiscal Year End Date	--03-26
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Current assets:
Cash and cash equivalents	$ 201,998	$ 214,491
Restricted cash	6,354	5,385
Trade accounts receivable, net of allowances for doubtful accounts of $338 and $288 at September 25, 2020 and March 27, 2020, respectively	57,926	59,457
Trade and other accounts receivable due from related party	16,783	30,851
Accounts receivable - other	2,780	1,796
Inventories	104,796	127,227
Prepaid expenses and other current assets	16,585	9,014
Total current assets	407,222	448,221
Property, plant and equipment, net	217,901	332,330
Deferred income tax assets	6,861	7,217
Goodwill	20,257	1,285
Intangible assets, net	36,274	19,958
Related party note receivable	51,377	0
Equity investment in related party	25,028	0
Other assets, net	14,779	8,810
Total assets	779,699	817,821
Current liabilities:
Trade accounts payable	23,856	20,762
Amounts due to related party	1,157	4,494
Accrued expenses and other current liabilities	64,929	56,855
Current portion of related party debt	0	25,000
Bank lines-of-credit	33,000	43,000
Total current liabilities	122,942	150,111
Related party notes payable, less current portion	0	17,700
Other long-term liabilities	21,251	15,878
Total liabilities	144,193	183,689
Commitments and contingencies (Note 16)
Stockholders' Equity:
Additional paid-in capital	439,732	458,697
Retained earnings	208,759	194,355
Accumulated other comprehensive loss	(14,133)	(19,976)
Equity attributable to Allegro MicroSystems, Inc.	634,464	633,182
Non-controlling interests	1,042	950
Total stockholders' equity	635,506	634,132
Total liabilities, non-controlling interest and stockholders' equity	779,699	817,821
Class A, $.01 par value; 12,500,000 shares authorized; 10,000,000 shares issued and outstanding at September 25, 2020 and March 27, 2020
Stockholders' Equity:
Common stock:	100	100
Class L, $.01 par value; 1,000,000 shares authorized; 638,298 shares issued and outstanding September 25, 2020; 622,470 shares issued and outstanding at March 27, 2020
Stockholders' Equity:
Common stock:	$ 6	$ 6

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Allowances	$ 338	$ 288
Common Stock, Class A
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	12,500,000	12,500,000
Common stock, shares issued (in shares)	10,000,000	10,000,000
Common stock, shares outstanding (in shares)	10,000,000	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)	1,000,000	1,000,000
Common stock, shares issued (in shares)	638,298	622,470
Common stock, shares outstanding (in shares)	638,298	622,470

Statement of Income (Including Gross Margin) (Statement) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Net sales	$ 136,649	$ 163,240	$ 251,650	$ 315,683
Cost of goods sold	74,879	94,634	134,179	187,690
Gross Profit	61,770	68,606	117,471	127,993
Operating expenses:
Research and development	25,130	25,952	49,510	52,080
Selling, general and administrative	24,238	27,593	51,027	53,121
Total operating expenses	49,368	53,545	100,537	105,201
Operating income	12,402	15,061	16,934	22,792
Other income (expense):
Interest income (expense), net	350	(65)	663	(70)
Foreign currency transaction (loss) gain	(1,318)	609	(1,186)	3,360
Income in earnings of equity investment	246	0	458	0
Other, net	20	(1,189)	213	(1,096)
Income before income taxes	11,700	14,416	17,082	24,986
Income tax provision	2,082	2,833	2,610	10,168
Net income	9,618	11,583	14,472	14,818
Net income attributable to non-controlling interests	34	18	68	69
Net income attributable to Allegro MicroSystems, Inc.	$ 9,584	$ 11,565	$ 14,404	$ 14,749
Net income attributable to Allegro MicroSystems, Inc. per share:
Basic and diluted (in dollars per share)	$ 0.96	$ 1.16	$ 1.44	$ 1.47
Weighted average shares outstanding:
Basic and diluted (in shares)	10,000,000	10,000,000	10,000,000	10,000,000
Non-Related Party Revenue
Net sales	$ 114,138	$ 146,615	$ 205,519	$ 282,891
Related Party Revenue
Net sales	$ 22,511	$ 16,625	$ 46,131	$ 32,792

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 9,618	$ 11,583	$ 14,472	$ 14,818
Foreign currency translation adjustment	1,900	(1,784)	6,180	(1,017)
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 income	11,518	9,799	20,339	13,801
Comprehensive (expense) income attributable to non-controlling interest	(31)	(33)	(24)	18
Comprehensive income attributable to Allegro MicroSystems, Inc.	$ 11,487	$ 9,766	$ 20,315	$ 13,819

- 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, Class A	Common Stock Common Stock, Class L	Additional Paid-In Capital	Retained Earnings	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	14,818						14,749		69
Stock-based compensation	748					748
Foreign currency translation adjustment	(1,017)							(999)	(18)
Issuance of Class L shares, net of forfeitures (in shares)					0
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 Sep. 27, 2019				10,000,000	607,620
Ending balance at Sep. 27, 2019	604,338			$ 100	$ 6	448,510	172,134	(17,277)	865
Beginning balance (in shares) at Jun. 28, 2019				10,000,000	607,620
Beginning balance at Jun. 28, 2019	594,165			$ 100	$ 6	448,136	160,569	(15,460)	814
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,583						11,565		18
Stock-based compensation	374					374
Foreign currency translation adjustment	(1,784)							(1,817)	33
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 Sep. 27, 2019				10,000,000	607,620
Ending balance at Sep. 27, 2019	604,338			$ 100	$ 6	448,510	172,134	(17,277)	865
Beginning balance (in shares) at Mar. 27, 2020		10,000,000	622,470	10,000,000	622,470
Beginning balance at Mar. 27, 2020	634,132			$ 100	$ 6	458,697	194,355	(19,976)	950
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	14,472						14,404		68
Stock-based compensation	1,025					1,025
Capitalization changes related to organizational structure of affiliates and direct and indirect interests in subsidiaries	(19,692)					(19,692)
Foreign currency translation adjustment	6,180							6,156	24
Issuance of Class L shares, net of forfeitures (in shares)					15,828
Issuance of Class L shares, net of forfeitures	0
Reclassification of certain class L shares	(298)					(298)
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 Sep. 25, 2020		10,000,000	638,298	10,000,000	638,298
Ending balance at Sep. 25, 2020	635,506			$ 100	$ 6	439,732	208,759	(14,133)	1,042
Beginning balance (in shares) at Jun. 26, 2020				10,000,000	638,298
Beginning balance at Jun. 26, 2020	623,935			$ 100	$ 6	439,679	199,175	(16,002)	977
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,618						9,584		34
Stock-based compensation	580					580
Capitalization changes related to organizational structure of affiliates and direct and indirect interests in subsidiaries	(527)					(527)
Foreign currency translation adjustment	1,900							1,869	31
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 Sep. 25, 2020		10,000,000	638,298	10,000,000	638,298
Ending balance at Sep. 25, 2020	$ 635,506			$ 100	$ 6	$ 439,732	$ 208,759	$ (14,133)	$ 1,042

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 14,472	$ 14,818
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	24,026	31,477
Deferred income taxes	1,307	(320)
Stock-based compensation	1,025	748
Loss on disposal of assets	293	559
Provisions for inventory and bad debt	209	1,941
Changes in operating assets and liabilities:
Trade accounts receivable	6,196	10,294
Accounts receivable - other	(1,292)	1,148
Inventories	(8,772)	3,043
Prepaid expenses and other assets	(16,725)	(3,863)
Trade accounts payable	2,793	(759)
Due to/from related parties	10,731	(19,601)
Accrued expenses and other current and long-term liabilities	(5,623)	(11,769)
Net cash provided by operating activities	28,640	27,716
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(18,091)	(18,199)
Acquisition of business, net of cash acquired	(8,500)	0
Proceeds from sales of property, plant and equipment	282	3,920
Contribution of cash balances due to divestiture of subsidiary	(16,335)	0
Net cash used in investing activities	(42,644)	(14,279)
CASH FLOWS FROM FINANCING ACTIVITIES:
Related party note receivable	0	30,000
Net cash provided by financing activities	0	30,000
Effect of exchange rate changes on Cash and cash equivalents and Restricted cash	2,480	(7,157)
Net (decrease) increase in Cash and cash equivalents and Restricted cash	(11,524)	36,280
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:	208,352	139,537
RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH:
Cash and cash equivalents and Restricted cash	208,352	139,537
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for interest	107	763
Cash paid for income taxes	6,385	4,582
Non-cash transactions:
Changes in Trade accounts payable related to Property, plant and equipment, net	(4,000)	(2,659)
Loans to cover purchase of common stock under employee stock plan	171	0
Deconsolidation related to Divestiture Transactions (Note 1)	$ 0	$ 0

Nature of the Business and Basis of Presentation

6 Months Ended

Sep. 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 the Company’s final prospectus on Form 424(b) filed with the SEC on October 30, 2020 (the “Prospectus”). 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 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. In order to affect this in-kind, non-cash transaction, Sanken contributed the forgiveness of the fair value of the entire related party notes payable of $42,700 owed 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. 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 $25,669 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 a tax impact of $419 for the fair value basis difference compared to book value and $458 of income earned during the six months ended September 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 $19,692 at September 25, 2020. This amount includes an estimated tax effect of $527 and $2,497 for the three- and six-month periods ended September 25, 2020, respectively, of which $419 was charged against the investment noted above.

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, who contracted with Sanken as their new channel for fulfillment of Sanken product sales in North America and Europe. Sanken will continue to provide distribution support for Allegro’s products in Japan. See Note 20, ”Related party transactions,” for further discussion.

In accordance with the divestiture transactions noted above, the following non-cash 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 Coronavirus

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 outbreak 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. Such risks include, if the business impacts of COVID-19

carry on for an extended period, 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. While the Company does not currently expect to use the proceeds from these borrowings for any near-term liquidity needs, it may use the proceeds for working capital and other general corporate purposes.

On March 27, 2020, the President of the United States signed and enacted 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”). The Company currently estimates a $1,680 cash acceleration is available to it as a result of this change and the Company plans to adjust its historical income tax filings accordingly. Additional income tax provisions of the Act are currently being evaluated and not expected to have a material impact. The CARES Act also contains a provision for deferred payment of 2020 employer payroll taxes after the date of enactment to future years. The Company expects to defer a portion of its remaining 2020 employer payroll taxes to subsequent years.

Financial Periods

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

Summary of Significant Accounting Policies	6 Months Ended
Summary of Significant Accounting Policies	Sep. 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 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 September 25, 2020 and March 27, 2020, the Company had $1,806 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 its creditworthiness of its customers and maintains allowances, to the extend 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 September 25, 2020 and March 27, 2020, Sanken accounted for 15.5% 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 ended. For the three- and six-month periods ended September 25, 2020, Sanken accounted for 16.5% and 18.3% of total net sales, respectively. No other customers accounted for 10% or more of total net sales for either of the three- and six-month periods ended September 25, 2020. For the three- and six-month periods ended September 27, 2019, Sanken accounted for 10.2% 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 six-month periods ended September 27, 2019. During the three-month period ended September 25, 2020 sales from customers located outside of the United States accounted for in the aggregate 84.7% of the Company’s total net sales, with Greater China accounting for 27.8% and Japan accounting for 16.4%. No other countries accounted for greater than 10% of total net sales for the three-month period ended September 25, 2020. During the six-month period ended September 25, 2020 sales from customers located outside of the United States in the aggregate accounted for 86.5% of the Company’s total net sales, with Greater China accounting for 27.8%, Japan accounting for 18.3% and South Korea accounting for 10.4%. No other countries accounted for greater than 10% of total net sales for the six-month period ended September 25, 2020. During the three-month period ended September 27, 2019 sales from customers located outside of the United States in the aggregate accounted for 81.2% of the Company’s total net sales, with Japan accounting for 26.0% and Greater China accounting for 22.5%. No other countries accounted for greater than 10% of total net sales for the three-month period ended September 27, 2019. During the six-month period ended September 27, 2019 sales from customers located outside of the United States in the aggregate accounted for 81.2% of the Company’s total net sales, with Japan accounting for 27.2% and Greater China accounting for 18.9%. No other countries accounted for greater than 10% of total net sales for the six-month period ended September 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 ASU No. 2016-02, “Leases (Topic 842)” (“ASU 2016-02” or “the new lease standard”) which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification determines whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. In addition, a lessee is required to record (i) a right-of-use asset and a lease liability on its balance sheet for all leases with accounting lease terms of more than 12 months regardless of whether it is an operating or financing lease and (ii) lease expense for operating leases and amortization and interest expense for financing leases. Leases with a term of 12 months or less may be accounted for similar to prior guidance for operating leases. In July 2018, the FASB issued ASU No. 2018-11, which added an optional transition method under the new lease standard that allows companies to adopt the standard as of the beginning of the year of adoption as opposed to the earliest comparative period presented. In November 2019, the FASB issued guidance delaying the effective date for all entities, except for public business entities. 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 it is currently evaluating the expected effect on its consolidated financial statements and related disclosures. 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 guidance delaying the effective date for all entities, except for public business entities. For public entities, this guidance was effective for annual periods beginning after December 15, 2018, including interim periods within those fiscal years. For nonpublic entities, this guidance is effective for annual periods beginning after December 15, 2020. 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 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

6 Months Ended

Sep. 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 acquisition date. 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	$	3,996
Property and equipment	57
Finite-life intangible assets	13,600
Indefinite-life intangible assets	2,400
Deferred tax liability	(3,843)
Goodwill	18,871
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-month period ended September 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

6 Months Ended

Sep. 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 six- month periods ended September 25, 2020 and September 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				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Core end market:
Automotive	$	89,479	$	98,209	$	165,857	$	190,607
Industrial	21,650		18,092		42,056		34,737
Other	25,520		20,542		43,737		38,329
Other applications:
Wafer foundry products	—		16,698		—		32,988
Distribution of Sanken products	—		9,699		—		19,022
Total net sales	$	136,649	$	163,240	$	251,650	$	315,683

Net sales by product:


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Power integrated circuits (“PIC”)	$	50,271	$	45,235	$	91,870	$	80,235
Magnetic sensors (“MS”)	86,097		91,608		159,499		183,438
Photonics	281		—		281		—
Wafer foundry products	—		16,698		—		32,988
Distribution of Sanken products	—		9,699		—		19,022
Total net sales	$	136,649	$	163,240	$	251,650	$	315,683

Net sales by geography:


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Americas:
United States	$	20,962	$	30,659	$	33,958	$	59,248
Other Americas	3,249		5,200		5,177		11,208
EMEA:
Europe	24,374		24,140		42,220		52,281
Asia:
Japan	22,511		42,472		46,131		85,940
Greater China	37,935		36,696		70,006		59,960
South Korea	12,515		13,950		26,127		27,294
Other Asia	15,103		10,123		28,031		19,752
Total net sales	$	136,649	$	163,240	$	251,650	$	315,683

The Company recognizes sales net of returns, credits issued, price protection adjustments and stock rotation rights. At September 25, 2020 and March 27, 2020, these adjustments were $19,337 and $17,473, respectively, and were netted against

trade accounts receivable in the unaudited consolidated balance sheets. These amounts represent activity of a charge of $1,864 and a credit of $412 for the six-month periods ended September 25, 2020 and September 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

6 Months Ended

Sep. 25, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

The following tables present information about the Company’s financial assets and liabilities as of September 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 September 25, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market fund deposits	$	41,342	$	—	$	—	$	41,342
Restricted cash:
Money market fund deposits	6,354		—		—		6,354
Total assets	$	47,696	$	—	$	—	$	47,696
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 six-month period ended September 25, 2020:


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

Balance at September 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 six-month periods ended September 25, 2020 and September 27, 2019, there were no transfers between 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

6 Months Ended

Sep. 25, 2020

Receivables [Abstract]

Trade Accounts Receivable, net

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


	September 25, 2020		March 27, 2020
Trade accounts receivable	$	93,657	$	107,223
Less:
Allowance for doubtful accounts	(338)		(288)
Returns and sales allowances	(18,999)		(17,185)
Related party trade accounts receivable	(16,394)		(30,293)
Total	$	57,926	$	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	50		64,316		64,366
Write-offs, net of recoveries	—		(62,502)		(62,502)
Balance at September 25, 2020	$	338	$	18,999	$	19,337


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	(201)		57,155		56,954
Write-offs, net of recoveries	—		(57,366)		(57,366)
Balance at September 27, 2019	$	211	$	17,396	$	17,607

Inventories

6 Months Ended

Sep. 25, 2020

Inventory Disclosure [Abstract]

Inventories

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


	September 25, 2020		March 27, 2020
Raw materials and supplies	$	9,415	$	12,411
Work in process	61,916		87,606
Finished goods	30,061		24,659
Finished goods – consigned	3,404		2,551
Total	$	104,796	$	127,227

In connection with the Acquisition, the Company acquired inventory with a stepped-up basis of $3,120 in the three- and six-month periods ended September 25, 2020. The Company recorded inventory provisions totaling $490 and $2,073 for the three- and six-month periods ended September 25, 2020, respectively, and $473 and $1,530 for the three- and six-month periods ended September 27, 2019, respectively.

Property, Plant and Equipment, net

6 Months Ended

Sep. 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:


	September 25, 2020		March 27, 2020
Land	$	23,419	$	27,898
Buildings, building improvements and leasehold improvements	89,433		150,402
Machinery and equipment	476,338		694,215
Office equipment	6,690		7,517
Construction in progress	18,504		27,919
Total	614,384		907,951
Less accumulated depreciation	(396,483)		(575,621)
Total	$	217,901	$	332,330

Total depreciation expense amounted to $11,797 and $22,606 in the three- and six-month periods ended September 25, 2020, respectively, and $15,540 and $30,570 in the three- and six-month periods ended September 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 September 25, 2020 and March 27, 2020 are as follows:


	September 25, 2020		March 27, 2020
United States	$	40,659	$	152,536
Philippines	127,274		106,618
Thailand	41,519		62,380
Other	9,842		12,112
Total	$	219,294	$	333,646

Amortization of prepaid tooling costs amounted to $19 and $36 for the three- and six-month periods ended September 25, 2020, respectively, and $30 and $62 in the three- and six-month periods ended September 27, 2019, respectively.

Goodwill and Intangible Assets

6 Months Ended

Sep. 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	18,871
Currency translation	101
Balance at September 25, 2020	$	20,257

Intangible assets, net is as follows:


	September 25, 2020
Description	Gross		Accumulated Amortization		Net Carrying Amount		Weighted- Average Lives
Patents	$	30,801	$	11,066	$	19,735	10 years
Customer relationships	6,193		5,797		396		9 years
Process technology	17,150		1,755		15,395		12 years
Trademarks	810		62		748		5 years
Other	32		32		—
Total	$	54,986	$	18,712	$	36,274


	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 three-month period ended September 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 $18,871. 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 $671 and $1,384 for the three- and six-month periods ended September 25, 2020, respectively, and $418 and $845 for the three- and six-month periods ended September 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 ten years. There were no such costs capitalized during either of the first six months of fiscal years 2020 or 2021.

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


Remainder of 2021	$	1,584
2022	3,057
2023	2,917
2024	2,788
2025	2,598
Thereafter	23,330
Total	$	36,274

Other Assets, net

6 Months Ended

Sep. 25, 2020

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

Other Assets, net

The composition of other assets, net is as follows:


	September 25, 2020		March 27, 2020
VAT receivables long-term, net	$	4,988	$	3,039
Deposits	2,376		2,399
Prepaid contracts long-term	3,609		1,282
Deferred offering costs	1,806		—
Other	2,000		2,090
Total	$	14,779	$	8,810

Accrued Expenses and Other Current Liabilities

6 Months Ended

Sep. 25, 2020

Payables and Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

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


	September 25, 2020		March 27, 2020
Accrued management incentive (LTIP)	$	748	$	11,488
Accrued management incentive (non-LTIP)	7,176		6,273
Accrued salaries and wages	18,105		12,069
Base acquisition purchase price due	17,244		—
Accrued vacation	5,804		7,146
Accrued severance	4,417		6,065
Accrued professional fees	4,258		4,036
Accrued income taxes	1,324		3,408
Accrued utilities	666		1,114
Other current liabilities	5,187		5,256
Total	$	64,929	$	56,855

Management Long-Term Incentive Plan

6 Months Ended

Sep. 25, 2020

Management Long-Term Incentive Plan

On August 28, 2015 the Company’s Board of Directors approved a Long-Term Cash Incentive Plan (“LTIP”) for certain employees. Under the LTIP, 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. The accrual activity, payments, removal due to divestitures and balances related to the LTIP 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)		—
Removal due to divestiture	(378)		(398)
Accruals	(270)		(1,037)
Balance at September 25, 2020	$	748	$	—

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

Bank Lines of Credit	6 Months Ended
Bank Lines of Credit	Sep. 25, 2020
Debt Disclosure [Abstract]
Bank Lines of Credit	Bank Lines of Credit On January 22, 2019, the Company, through its subsidiaries, entered into a revolving line-of-credit agreement, with a financial institution, that provides for a maximum borrowing capacity of $25,000. The revolving line-of credit bears interest at LIBOR on the day of the advance plus a 0.4% spread payable upon maturity of the draws, and expires 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, and as of September 25, 2020 the Company’s outstanding balance under the revolving line-of-credit agreement was $25,000. The revolving line of credit is secured, for 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. See Note 21, “Subsequent Events.” On March 27, 2006, the Company, through its subsidiaries, 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 bears interest at LIBOR on the day of the advance plus 1.0% spread payable upon maturity of the draws and is guaranteed by Sanken. Under the terms of the revolving line-of-credit agreement, the principal is 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 $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 provides 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 $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, and as of September 25, 2020 the Company’s outstanding balance under the line-of-credit agreement was $8,000. In connection with entering into a new revolving credit facility, the Company used cash on hand to repay all amounts outstanding under the line-of-credit and terminated all commitments thereunder. See Note 21, “Subsequent Events.” 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 $1,235 at September 25, 2020) at the bank’s prevailing interest rate, which was approximately 4.6% at both September 25, 2020 and March 27, 2020. The line-of credit expires on August 31, 2021. There were no borrowings outstanding under this line-of-credit as of September 25, 2020 or 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 $1,544 at September 25, 2020) at the bank’s prevailing interest rate. The line-of credit expires on June 30, 2021. There were no borrowings outstanding under this line-of-credit as of September 25, 2020 or 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 will be available to be used for working capital, general corporate or other purposes during the COVID-19 crisis into fiscal year 2021. After the divestiture of PSL, the remaining $33,000 of bank lines-of-credit was classified as short-term as of September 25, 2020.

Other Long-Term Liabilities

6 Months Ended

Sep. 25, 2020

Other Liabilities Disclosure [Abstract]

Other Long-Term Liabilities

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


	September 25, 2020		March 27, 2020
Accrued management incentive (LTIP)	$	—	$	2,439
Accrued management incentive (non-LTIP)	1,012		2,304
Accrued retirement	9,213		8,005
Accrued contingent consideration	7,800		—
Provision for uncertain tax positions (net)	2,952		2,855
Other	274		275
Total	$	21,251	$	15,878

Retirement Plans

6 Months Ended

Sep. 25, 2020

Retirement Benefits [Abstract]

Retirement Plans

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 cost 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 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 Income

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


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Service cost	$	277	$	238	$	547	$	475
Interest cost	156		168		308		334
Expected return on plan assets	(74)		(82)		(152)		(164)
Net acquired/transferred obligation	—		—		—		—
Amortization of net transition asset	—		(3)		—		(6)
Amortization of prior service cost	2		2		4		4
Actuarial loss	45		24		79		48
Net periodic pension expense	$	406	$	347	$	786	$	691

Information on Plan Assets

The table below sets forth the fair value of the entity’s plan assets as of September 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 Prospectus.


	Fair Value at September 25, 2020		Level 1		Level 2		Level 3
Assets of non-U.S. defined benefit plan:
Government securities	$	1,862	$	1,862	$	—	$	—
Unit investment trust fund	1,098		—		1,098		—
Loans	605		—		—		605
Bonds	1,309		—		1,309		—
Stocks and other investments	1,820		692		1		1,127
Total	$	6,694	$	2,554	$	2,408	$	1,732


	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 six-month period ended September 25, 2020:


	Level 3 Non-U.S. Defined Plan Assets
	Loans		Stocks
Balance at March 27, 2020	$	756	$	364
Additions during the year	120		—
Redemptions during the year	(303)		—
Revaluation of equity securities	—		745
Change in foreign currency exchange rates	32		18
Balance at September 25, 2020	$	605	$	1,127

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 six-month periods ended September 25, 2020 the Company contributed approximately $247 and $487 to its non-U.S. pension plan, respectively, and during the three- and six-month periods ended September 27, 2019 the Company contributed approximately $230 and $463 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 September 25, 2020 and March 27, 2020, respectively (approximately $1,053 and $975 at September 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 $1,040 and $2,069 for the three- and six-month periods ended September 25, 2020, respectively, and approximately $960 and $2,007 for the three- and six-month periods ended September 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 $206 and $385 for the three- and six-month periods ended September 25, 2020, respectively, and approximately $183 and $359 for the three- and six-month periods ended September 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 six-month periods ended September 27, 2019 was $401 and $934, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Commitment and Contingencies	6 Months Ended
Commitment and Contingencies	Sep. 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 the 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 as of September 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 September 25, 2020 or March 27, 2020.

Net Income per Share

6 Months Ended

Sep. 25, 2020

Earnings Per Share [Abstract]

Net Income per Share

The following table sets forth the computation of diluted net income attributable to Allegro MicroSystems, Inc. per share:


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Net income attributable to Allegro MicroSystems, Inc.	$	9,584	$	11,565	$	14,404	$	14,749
Net income attributable to common stockholders	9,618		11,583		14,472		14,818
Weighted average basic and diluted common shares	10,000,000		10,000,000		10,000,000		10,000,000
Basic and diluted net income attributable to Allegro MicroSystems, Inc. per share	$	0.96	$	1.16	$	1.44	$	1.47
Basic and diluted net income attributable to common stockholders per share	$	0.96	$	1.16	$	1.45	$	1.48

Class A shares are entitled to a priority dividend of 8%. After Class A shareholders receive an annualized return on capital of 8%, distributions of the remaining value are 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 six-month periods ended September 25, 2020 and September 27, 2019, the Company did not allocate income to the Class L shares 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.

Unaudited Pro Forma Net Income per Share

Unaudited pro forma basic and diluted net income per share attributable to Allegro MicroSystems, Inc. for the three- and six-month periods ended September 25, 2020 have been prepared to give effect to the Common Stock Conversion as described below in Note 21, “Subsequent Events” as if such event had occurred on September 25, 2020.


	Three-Month Period Ended September 25, 2020		Six-Month Period Ended September 25, 2020
Numerator:


Net income, as reported	$	9,584	$	14,404
Denominator:
Weighted-average shares used to compute net income per share attributable to common shareholders, basic	10,000,000		10,000,000
Pro forma adjustments to reflect the Common Stock Conversion	156,500,000		156,500,000
Pro forma adjustments to reflect the Company’s buy-back of shares to cover withholding taxes	(2,068,234)		(2,068,234)
Total	164,431,766		164,431,766
Pro forma net income per share attributable to common shareholders	$	0.06	$	0.09

Common Stock and Stock-Based Compensation

6 Months Ended

Sep. 25, 2020

Share-based Payment Arrangement [Abstract]

Common Stock and Stock-Based Compensation

Common Stock and Stock-Based CompensationThe Company has 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 common shares. The previous single class of common stock was retired in full. The Company sold 2,880,000 of newly-issued shares of Class A common stock, representing a 28.8% ownership interest, to OEP for cash consideration of $291,000. 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 are entitled to dividends, when, and if declared by the Board of Directors. Holders of shares of Class A common stock are 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 are 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 entitles 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 are 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 will 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 initial public offering (“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 will convert into Class A common stock.

Also, in connection with the OEP transaction, the Company granted 400,000 of unvested Class A shares and 597,400 of unvested Class L shares to certain Company employees. The Class A shares 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 Class A shares. If such a change in control or IPO occurred, the unvested Class A shares would immediately become vested and the Company would recognize $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 vest on a straight-line basis over a service period of four years. Class L unvested shares have no other vesting conditions. If an IPO occured, 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 will accelerate vesting.

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


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Cost of sales	$	53	$	45	$	150	$	90
Research and development	32		26		53		45
Selling, general and administrative	495		303		822		613
Total stock-based compensation	$	580	$	374	$	1,025	$	748

The Company issued 15,828 Class L shares during the six-month period ended September 25, 2020 with a weighted average price per share of $33.83. The Company issued no Class L shares during the six-month period ended September 27, 2019. There were 638,298 Class L shares outstanding at September 25, 2020 with a weighted average price per share of $11.99.

Income Taxes

6 Months Ended

Sep. 25, 2020

Income Tax Disclosure [Abstract]

Income Taxes

The Company recorded the following tax provision in its unaudited consolidated statements of income:


	Three-Month Period Ended						Six-Month Period Ended
	September 25, 2020			September 27, 2019			September 25, 2020			September 27, 2019
Operating taxes	$	1,589		$	2,566		$	2,405		$	4,277
Discrete tax items	493			267			205			5,891
Provision for income taxes	$	2,082		$	2,833		$	2,610		$	10,168
Annual operating tax rate	13.6		%	17.8		%	14.1		%	17.1		%
Effective tax rate	17.8		%	19.7		%	15.3		%	40.7		%

The Company is subject to income taxes in the United States and the foreign jurisdictions in which it does business. The Company’s income tax provision is comprised of federal, state, local and foreign taxes based on income in multiple jurisdictions and changes in uncertain tax positions. The primary region that is applicable to the determination of the Company’s effective tax rate is the United States. Effective tax rates vary depending on the relative proportion of foreign to U.S. income, the utilization of foreign tax credits and research and development tax credits, changes in corporate structure, changes in the valuation of the Company’s deferred tax assets and changes in tax laws and interpretations. 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 our income tax reserves and expense.

Should actual events or results differ from our 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.

The effective tax rate is comprised of an estimated annual operating tax rate and the tax impact of discrete tax adjustments. The effective tax rate for the six-month period ended September 25, 2020 is below the U.S. statutory tax rate of 21.0% primarily as a result of the benefit of the Research and Development Credits and the Foreign Derived Intangible Income provision of the 2017 Tax Cut and Jobs Act (“U.S. Tax Reform”).

The decrease in the Company’s provision for income tax and the effective tax rate for the six-month period ended September 25, 2020 as compared to the six-month period ended September 27, 2019 was primarily driven by a discrete tax expense of approximately $5,500 recorded in the first quarter of fiscal year 2020, for the settlement of IRS transfer pricing audits for years 2016, 2017, and 2018. Additionally, the Company estimates an increased benefit of the Foreign Derived Intangible Income provision of U.S. Tax Reform for fiscal year 2021 as compared to fiscal year 2020 resulting from an increase in forecasted taxable income year over year.

- 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	6 Months Ended
Related Party Transactions	Sep. 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 $22,511 and $46,131 during the three- and six-month periods ended September 25, 2020, respectively, and $16,625 and $32,792 during the three- and six-month periods ended September 27, 2019, respectively. Trade accounts receivables, net of allowances from Sanken totaled $11,654 and $30,293 as of September 25, 2020 and March 27, 2020, respectively. Other accounts receivable from Sanken totaled $389 and $558 as of September 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 $9,699 and $19,022 during the three- and six-month periods ended September 27, 2019. On March 28, 2020, the Company formally terminated its distribution agreement with Sanken to distribute Sanken’s products. Purchases of various products from Sanken totaled $8,569 and $16,479 for the three- and six-month periods ended September 27, 2019. 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 $720 in the three- and six-month periods ended September 27, 2019. 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 of 2.52% and was repaid in April 2019. Interest income related to the loan to Sanken was $55 in the six-month period ended September 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 includes 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 and lines-of-credit for the three- and six-month periods ended September 27, 2019 amounted to $383 and $795 and related party interest paid for the same periods amounted to $730 and $754, respectively. As of March 27, 2020, the related party notes payable balance of $17,700 was classified in the unaudited 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 September 25, 2020, the Company reflected a related accounts receivable balance of $4,909. This amount includes a reduction of $3,368 from payments made by PSL during the six-month period ended September 25, 2020. In addition, 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 $360 and $720 in the three- and six-month periods ended September 27, 2019. The Company continues to purchase in-process products from PSL. Purchases of various products from PSL totaled $9,967 and $21,890 for the three- and six-month periods ended September 25, 2020. This amount includes $1,700 and $3,500 of price support payments made for the three- and six-month periods ended September 25, 2020 and the reduction of $1,760 and $1,198 of intercompany balances for the three- and six-month periods ended September 25, 2020. Accounts payable to PSL included in amounts due to related party totaled $1,157 as of September 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 is now classified on the Company’s balance sheet as related party note receivable. The related party note receivable held by the Company has a maturity date of March 28, 2027 and bears interest rate of 2.70%, which is 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 September 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 six-month periods ended September 25, 2020 and September 27, 2019, the Company paid aggregate fees of $90 each quarter to Mr. Kazerounian pursuant to the Consulting Agreement. Director and Executive Officer Promissory Notes From time to time, the Company has 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 $654 and $506 of promissory notes outstanding as of as of September 25, 2020 and March 27, 2020, respectively.

Subsequent Events

6 Months Ended

Sep. 25, 2020

Subsequent Events [Abstract]

Subsequent Events

On November 2, 2020, the Company completed its IPO. The Company’s common stock is now listed on the Nasdaq Global Select Market under the ticker symbol “ALGM.” On November 2, 2020 the Company closed 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 were sold by selling stockholders, resulting in net proceeds to the Company of approximately $320,849, after deducting $20,125 of underwriting discounts and $9,026 of estimated offering costs.

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, 2,066,468 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	7,816,614	459,749	8,276,363
Total	163,972,017	459,749	164,431,766

The Company has retrospectively adjusted its earnings per share to reflect the conversion of Class A common stock and Class L common stock to Common Stock resulting from the conversion. See Note 17 “Net Income per Share.”

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, and $1,593 in connection with the automatic acceleration of 25% of the standard vesting term of shares of Class L common stock.

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 Long-Term Cash Incentive Plan (the “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 589,987 and 348,999 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.

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 (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 (the “Revolving Credit Facility” and, together with the Term Loan Facility, the “Senior Secured Credit Facilities”). In connection with entering into the Revolving Credit Facility, the Company used cash on hand to repay all amounts outstanding under AML’s $25,000 line-of-credit agreement with Mizuho Bank, Ltd and AML’s $8,000 line-of-credit agreement with the Bank of Mitsubishi UFJ and terminated all commitments thereunder.

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.

In October 2020, the Company used proceeds from the Term Loan Facility, together with cash on hand, to pay an aggregate cash dividend of $400,000 to holders of its Class A common stock.

On October 14, 2020, the outstanding principal amount of, and accrued and unpaid interest on, the $51,377 related party note receivable due to the Company from PSL in connection with the PSL divestiture was prepaid in full.

On November 20, 2020, the Company provided notice of repayment of $300,000 of the outstanding $325,000 Term Loan Facility using proceeds from the Company’s recently completed IPO. The notice of repayment is expected to occur during the third quarter of fiscal 2021.

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 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 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 its creditworthiness of its customers and maintains allowances, to the extend necessary, for potential credit losses based upon the aging of its accounts receivable balances and known collection issues.
Impact of Recently Adopted Accounting Standards and 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 ASU No. 2016-02, “Leases (Topic 842)” (“ASU 2016-02” or “the new lease standard”) which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification determines whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. In addition, a lessee is required to record (i) a right-of-use asset and a lease liability on its balance sheet for all leases with accounting lease terms of more than 12 months regardless of whether it is an operating or financing lease and (ii) lease expense for operating leases and amortization and interest expense for financing leases. Leases with a term of 12 months or less may be accounted for similar to prior guidance for operating leases. In July 2018, the FASB issued ASU No. 2018-11, which added an optional transition method under the new lease standard that allows companies to adopt the standard as of the beginning of the year of adoption as opposed to the earliest comparative period presented. In November 2019, the FASB issued guidance delaying the effective date for all entities, except for public business entities. 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 it is currently evaluating the expected effect on its consolidated financial statements and related disclosures. 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 guidance delaying the effective date for all entities, except for public business entities. For public entities, this guidance was effective for annual periods beginning after December 15, 2018, including interim periods within those fiscal years. For nonpublic entities, this guidance is effective for annual periods beginning after December 15, 2020. 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 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)

6 Months Ended

Sep. 25, 2020

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Cash Flow Impact of Divestiture


	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)

6 Months Ended

Sep. 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	$	3,996
Property and equipment	57
Finite-life intangible assets	13,600
Indefinite-life intangible assets	2,400
Deferred tax liability	(3,843)
Goodwill	18,871
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)

6 Months Ended

Sep. 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				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Core end market:
Automotive	$	89,479	$	98,209	$	165,857	$	190,607
Industrial	21,650		18,092		42,056		34,737
Other	25,520		20,542		43,737		38,329
Other applications:
Wafer foundry products	—		16,698		—		32,988
Distribution of Sanken products	—		9,699		—		19,022
Total net sales	$	136,649	$	163,240	$	251,650	$	315,683

Revenue from External Customers by Products and Services

Net sales by product:


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Power integrated circuits (“PIC”)	$	50,271	$	45,235	$	91,870	$	80,235
Magnetic sensors (“MS”)	86,097		91,608		159,499		183,438
Photonics	281		—		281		—
Wafer foundry products	—		16,698		—		32,988
Distribution of Sanken products	—		9,699		—		19,022
Total net sales	$	136,649	$	163,240	$	251,650	$	315,683

Revenue from External Customers by Geographic Areas

Net sales by geography:


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Americas:
United States	$	20,962	$	30,659	$	33,958	$	59,248
Other Americas	3,249		5,200		5,177		11,208
EMEA:
Europe	24,374		24,140		42,220		52,281
Asia:
Japan	22,511		42,472		46,131		85,940
Greater China	37,935		36,696		70,006		59,960
South Korea	12,515		13,950		26,127		27,294
Other Asia	15,103		10,123		28,031		19,752
Total net sales	$	136,649	$	163,240	$	251,650	$	315,683

Fair Value Measurements (Tables)

6 Months Ended

Sep. 25, 2020

Fair Value Disclosures [Abstract]

Fair Value, by Balance Sheet Grouping


	Fair Value Measurement at September 25, 2020 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market fund deposits	$	41,342	$	—	$	—	$	41,342
Restricted cash:
Money market fund deposits	6,354		—		—		6,354
Total assets	$	47,696	$	—	$	—	$	47,696
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 six-month period ended September 25, 2020:


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

Balance at September 25, 2020	$	7,800

Trade Accounts Receivable, net (Tables)

6 Months Ended

Sep. 25, 2020

Receivables [Abstract]

Schedule of Trade Accounts Receivable, Net

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


	September 25, 2020		March 27, 2020
Trade accounts receivable	$	93,657	$	107,223
Less:
Allowance for doubtful accounts	(338)		(288)
Returns and sales allowances	(18,999)		(17,185)
Related party trade accounts receivable	(16,394)		(30,293)
Total	$	57,926	$	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	50		64,316		64,366
Write-offs, net of recoveries	—		(62,502)		(62,502)
Balance at September 25, 2020	$	338	$	18,999	$	19,337


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	(201)		57,155		56,954
Write-offs, net of recoveries	—		(57,366)		(57,366)
Balance at September 27, 2019	$	211	$	17,396	$	17,607

Inventories (Tables)

6 Months Ended

Sep. 25, 2020

Inventory Disclosure [Abstract]

Schedule of Inventories

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


	September 25, 2020		March 27, 2020
Raw materials and supplies	$	9,415	$	12,411
Work in process	61,916		87,606
Finished goods	30,061		24,659
Finished goods – consigned	3,404		2,551
Total	$	104,796	$	127,227

Property, Plant and Equipment, net (Tables)

6 Months Ended

Sep. 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:


	September 25, 2020		March 27, 2020
Land	$	23,419	$	27,898
Buildings, building improvements and leasehold improvements	89,433		150,402
Machinery and equipment	476,338		694,215
Office equipment	6,690		7,517
Construction in progress	18,504		27,919
Total	614,384		907,951
Less accumulated depreciation	(396,483)		(575,621)
Total	$	217,901	$	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 September 25, 2020 and March 27, 2020 are as follows:


	September 25, 2020		March 27, 2020
United States	$	40,659	$	152,536
Philippines	127,274		106,618
Thailand	41,519		62,380
Other	9,842		12,112
Total	$	219,294	$	333,646

Goodwill and Intangible Assets (Tables)

6 Months Ended

Sep. 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	18,871
Currency translation	101
Balance at September 25, 2020	$	20,257

Schedule of Intangible Assets, Net

Intangible assets, net is as follows:


	September 25, 2020
Description	Gross		Accumulated Amortization		Net Carrying Amount		Weighted- Average Lives
Patents	$	30,801	$	11,066	$	19,735	10 years
Customer relationships	6,193		5,797		396		9 years
Process technology	17,150		1,755		15,395		12 years
Trademarks	810		62		748		5 years
Other	32		32		—
Total	$	54,986	$	18,712	$	36,274


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


Remainder of 2021	$	1,584
2022	3,057
2023	2,917
2024	2,788
2025	2,598
Thereafter	23,330
Total	$	36,274

Other Assets, net (Tables)

6 Months Ended

Sep. 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:


	September 25, 2020		March 27, 2020
VAT receivables long-term, net	$	4,988	$	3,039
Deposits	2,376		2,399
Prepaid contracts long-term	3,609		1,282
Deferred offering costs	1,806		—
Other	2,000		2,090
Total	$	14,779	$	8,810

Accrued Expenses and Other Current Liabilities (Tables)

6 Months Ended

Sep. 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:


	September 25, 2020		March 27, 2020
Accrued management incentive (LTIP)	$	748	$	11,488
Accrued management incentive (non-LTIP)	7,176		6,273
Accrued salaries and wages	18,105		12,069
Base acquisition purchase price due	17,244		—
Accrued vacation	5,804		7,146
Accrued severance	4,417		6,065
Accrued professional fees	4,258		4,036
Accrued income taxes	1,324		3,408
Accrued utilities	666		1,114
Other current liabilities	5,187		5,256
Total	$	64,929	$	56,855

Management Long-Term Incentive Plan (Tables)

6 Months Ended

Sep. 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 LTIP 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)		—
Removal due to divestiture	(378)		(398)
Accruals	(270)		(1,037)
Balance at September 25, 2020	$	748	$	—

Other Long-Term Liabilities (Tables)

6 Months Ended

Sep. 25, 2020

Other Liabilities Disclosure [Abstract]

Schedule of Other Long-Term Liabilities

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


	September 25, 2020		March 27, 2020
Accrued management incentive (LTIP)	$	—	$	2,439
Accrued management incentive (non-LTIP)	1,012		2,304
Accrued retirement	9,213		8,005
Accrued contingent consideration	7,800		—
Provision for uncertain tax positions (net)	2,952		2,855
Other	274		275
Total	$	21,251	$	15,878

Retirement Plans (Tables)

6 Months Ended

Sep. 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				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Service cost	$	277	$	238	$	547	$	475
Interest cost	156		168		308		334
Expected return on plan assets	(74)		(82)		(152)		(164)
Net acquired/transferred obligation	—		—		—		—
Amortization of net transition asset	—		(3)		—		(6)
Amortization of prior service cost	2		2		4		4
Actuarial loss	45		24		79		48
Net periodic pension expense	$	406	$	347	$	786	$	691

Fair Value of Entity's Plan Assets


	Fair Value at September 25, 2020		Level 1		Level 2		Level 3
Assets of non-U.S. defined benefit plan:
Government securities	$	1,862	$	1,862	$	—	$	—
Unit investment trust fund	1,098		—		1,098		—
Loans	605		—		—		605
Bonds	1,309		—		1,309		—
Stocks and other investments	1,820		692		1		1,127
Total	$	6,694	$	2,554	$	2,408	$	1,732


	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 six-month period ended September 25, 2020:


	Level 3 Non-U.S. Defined Plan Assets
	Loans		Stocks
Balance at March 27, 2020	$	756	$	364
Additions during the year	120		—
Redemptions during the year	(303)		—
Revaluation of equity securities	—		745
Change in foreign currency exchange rates	32		18
Balance at September 25, 2020	$	605	$	1,127

Net Income per Share (Tables)

6 Months Ended

Sep. 25, 2020

Earnings Per Share [Abstract]

Schedule of Computation of Net Income per Share and Unaudited Pro Forma Net Income per Share

The following table sets forth the computation of diluted net income attributable to Allegro MicroSystems, Inc. per share:


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Net income attributable to Allegro MicroSystems, Inc.	$	9,584	$	11,565	$	14,404	$	14,749
Net income attributable to common stockholders	9,618		11,583		14,472		14,818
Weighted average basic and diluted common shares	10,000,000		10,000,000		10,000,000		10,000,000
Basic and diluted net income attributable to Allegro MicroSystems, Inc. per share	$	0.96	$	1.16	$	1.44	$	1.47
Basic and diluted net income attributable to common stockholders per share	$	0.96	$	1.16	$	1.45	$	1.48


	Three-Month Period Ended September 25, 2020		Six-Month Period Ended September 25, 2020
Numerator:


Net income, as reported	$	9,584	$	14,404
Denominator:
Weighted-average shares used to compute net income per share attributable to common shareholders, basic	10,000,000		10,000,000
Pro forma adjustments to reflect the Common Stock Conversion	156,500,000		156,500,000
Pro forma adjustments to reflect the Company’s buy-back of shares to cover withholding taxes	(2,068,234)		(2,068,234)
Total	164,431,766		164,431,766
Pro forma net income per share attributable to common shareholders	$	0.06	$	0.09

Common Stock and Stock-Based Compensation (Tables)

6 Months Ended

Sep. 25, 2020

Share-based Payment Arrangement [Abstract]

Schedule of Stock-Based Compensation Expense

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


	Three-Month Period Ended				Six-Month Period Ended
	September 25, 2020		September 27, 2019		September 25, 2020		September 27, 2019
Cost of sales	$	53	$	45	$	150	$	90
Research and development	32		26		53		45
Selling, general and administrative	495		303		822		613
Total stock-based compensation	$	580	$	374	$	1,025	$	748

Income Taxes (Tables)

6 Months Ended

Sep. 25, 2020

Income Tax Disclosure [Abstract]

Schedule of Tax Provision

The Company recorded the following tax provision in its unaudited consolidated statements of income:


	Three-Month Period Ended						Six-Month Period Ended
	September 25, 2020			September 27, 2019			September 25, 2020			September 27, 2019
Operating taxes	$	1,589		$	2,566		$	2,405		$	4,277
Discrete tax items	493			267			205			5,891
Provision for income taxes	$	2,082		$	2,833		$	2,610		$	10,168
Annual operating tax rate	13.6		%	17.8		%	14.1		%	17.1		%
Effective tax rate	17.8		%	19.7		%	15.3		%	40.7		%

Subsequent Events (Tables)

6 Months Ended

Sep. 25, 2020

Subsequent Events [Abstract]

Schedule of Conversions of Stock


	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	7,816,614	459,749	8,276,363
Total	163,972,017	459,749	164,431,766

Nature of the Business and Basis of Presentation - Additional Information (Details) $ in Thousands		1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 28, 2020 USD ($)	Mar. 31, 2020 USD ($)	Oct. 31, 2017	Sep. 25, 2020 USD ($) location continent	Mar. 27, 2020 USD ($)	Sep. 25, 2020 USD ($) location continent	Sep. 27, 2019 USD ($)
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				$ 25,028	$ 0	25,028
Adjustments to additional paid in capital, capitalization changes				527		19,692
COVID-19
Noncash or Part Noncash Divestitures [Line Items]
Proceeds from lines of credit		$ 43,000			$ 43,000
CARES Act, estimated cash acceleration available as a result of change in depreciation rates				1,680		1,680
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	$ 25,669
Effective income tax rate reconciliation, divestiture, amount						419
Income from equity method investments						458
Adjustments to additional paid in capital, capitalization changes						19,692
Adjustments to additional paid in capital, income tax benefit from noncash or part noncash divestiture				$ 527		$ 2,497
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

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 ($)	Sep. 25, 2020	Mar. 27, 2020
Accounting Policies [Abstract]
Deferred offering costs	$ 1,806,000	$ 0

Summary of Significant Accounting Policies - Concentrations of Credit Risk and Significant Customers (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019	Mar. 27, 2020
Revenue Benchmark \| Geographic Concentration Risk \| Non-US
Concentration Risk [Line Items]
Concentration risk, percentage	84.70%	81.20%	86.50%	81.20%
Revenue Benchmark \| Geographic Concentration Risk \| Greater China
Concentration Risk [Line Items]
Concentration risk, percentage	27.80%	22.50%	27.80%	18.90%
Revenue Benchmark \| Geographic Concentration Risk \| Japan
Concentration Risk [Line Items]
Concentration risk, percentage	16.40%	26.00%	18.30%	27.20%
Revenue Benchmark \| Geographic Concentration Risk \| South Korea
Concentration Risk [Line Items]
Concentration risk, percentage			10.40%
Sanken \| Trade Accounts Receivable \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage			15.50%		33.80%
Sanken \| Revenue Benchmark \| Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	16.50%	10.20%	18.30%	10.40%

Acquisition - Additional Information (Details) $ in Thousands		6 Months Ended
	Aug. 28, 2020 USD ($)	Sep. 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	Sep. 25, 2020	Mar. 27, 2020
Estimated fair value of assets acquired and liabilities assumed:
Goodwill		$ 20,257	$ 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	3,996
Property and equipment	57
Finite-life intangible assets	13,600
Indefinite-life intangible assets	2,400
Deferred tax liability	(3,843)
Goodwill	18,871
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		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 136,649	$ 163,240	$ 251,650	$ 315,683
Automotive
Disaggregation of Revenue [Line Items]
Total net sales	89,479	98,209	165,857	190,607
Industrial
Disaggregation of Revenue [Line Items]
Total net sales	21,650	18,092	42,056	34,737
Other
Disaggregation of Revenue [Line Items]
Total net sales	25,520	20,542	43,737	38,329
Wafer foundry products
Disaggregation of Revenue [Line Items]
Total net sales	0	16,698	0	32,988
Distribution of Sanken products
Disaggregation of Revenue [Line Items]
Total net sales	$ 0	$ 9,699	$ 0	$ 19,022

- 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
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-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		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 136,649	$ 163,240	$ 251,650	$ 315,683
Power integrated circuits (“PIC”)
Disaggregation of Revenue [Line Items]
Total net sales	50,271	45,235	91,870	80,235
Magnetic sensors (“MS”)
Disaggregation of Revenue [Line Items]
Total net sales	86,097	91,608	159,499	183,438
Photonics
Disaggregation of Revenue [Line Items]
Total net sales	281	0	281	0
Wafer foundry products
Disaggregation of Revenue [Line Items]
Total net sales	0	16,698	0	32,988
Distribution of Sanken products
Disaggregation of Revenue [Line Items]
Total net sales	$ 0	$ 9,699	$ 0	$ 19,022

- Definition

+ References

+ Details

Revenue from Contract with Customers - Net Sales by Geography (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 136,649	$ 163,240	$ 251,650	$ 315,683
United States
Disaggregation of Revenue [Line Items]
Total net sales	20,962	30,659	33,958	59,248
Other Americas
Disaggregation of Revenue [Line Items]
Total net sales	3,249	5,200	5,177	11,208
Europe
Disaggregation of Revenue [Line Items]
Total net sales	24,374	24,140	42,220	52,281
Japan
Disaggregation of Revenue [Line Items]
Total net sales	22,511	42,472	46,131	85,940
Greater China
Disaggregation of Revenue [Line Items]
Total net sales	37,935	36,696	70,006	59,960
South Korea
Disaggregation of Revenue [Line Items]
Total net sales	12,515	13,950	26,127	27,294
Other Asia
Disaggregation of Revenue [Line Items]
Total net sales	$ 15,103	$ 10,123	$ 28,031	$ 19,752

- Definition

+ References

+ Details

Revenue from Contract with Customers - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Mar. 27, 2020
Revenue from Contract with Customer [Abstract]
Trade accounts receivable, returns, credits issued, and price protection adjustments, current	$ 19,337		$ 17,473
Trade accounts receivable, returns, credits issued, and price protection adjustments expense (credit)	$ 1,864	$ (412)

Fair Value Measurements - Assets And Liabilities Measured At Fair Value (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Assets:
Total assets	$ 47,696	$ 51,722
Liabilities:
Contingent consideration	7,800
Total liabilities	7,800
Level 1
Assets:
Total assets	47,696	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	41,342	46,337
Restricted cash and restricted cash equivalents, fair value disclosure	6,354	5,385
Money Market Funds \| Level 1
Assets:
Cash and cash equivalents, fair value disclosure	41,342	46,337
Restricted cash and restricted cash equivalents, fair value disclosure	6,354	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	6 Months Ended
	Sep. 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	Sep. 25, 2020	Mar. 27, 2020	Sep. 27, 2019	Mar. 29, 2019
Receivables [Abstract]
Trade accounts receivable	$ 93,657	$ 107,223
Less:
Allowances	(338)	(288)	$ (211)	$ (412)
Returns and sales allowances	(18,999)	(17,185)	$ (17,396)	$ (17,607)
Related party trade accounts receivable	(16,394)	(30,293)
Trade accounts receivable, net	$ 57,926	$ 59,457

Trade Accounts Receivable, net - Schedule of Changes in Allowance For Doubtful Accounts and Sales Returns and Sales Allowances (Details) - USD ($) $ in Thousands	6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019
Allowance for Doubtful Accounts
Balance at the beginning of the period	$ 288	$ 412
Charged to costs and expenses or revenue	50	(201)
Write-offs, net of recoveries	0	0
Balance at the end of the period	338	211
Returns and Sales Allowances
Balance at the beginning of the period	17,185	17,607
Charged to costs and expenses or revenue	64,316	57,155
Write-offs, net of recoveries	(62,502)	(57,366)
Balance at the end of the period	18,999	17,396
Total
Balance at the beginning of the period	17,473	18,019
Charged to costs and expenses or revenue	64,366	56,954
Write-offs, net of recoveries	(62,502)	(57,366)
Balance at the end of the period	$ 19,337	$ 17,607

Inventories - Schedule Of Inventory (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 9,415	$ 12,411
Work in process	61,916	87,606
Finished goods	30,061	24,659
Finished goods – consigned	3,404	2,551
Total	$ 104,796	$ 127,227

Inventories - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Inventories - Narrative (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Inventory [Line Items]
Recorded inventory provisions	$ 490	$ 473	$ 2,073	$ 1,530
Voxtel
Inventory [Line Items]
Inventory acquired, step up basis				$ 3,120

Property, Plant and Equipment, net - Schedule of PPE (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Property, Plant and Equipment [Line Items]
Total	$ 614,384	$ 907,951
Less accumulated depreciation	(396,483)	(575,621)
Total	217,901	332,330
Land
Property, Plant and Equipment [Line Items]
Total	23,419	27,898
Buildings, building improvements and leasehold improvements
Property, Plant and Equipment [Line Items]
Total	89,433	150,402
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total	476,338	694,215
Office equipment
Property, Plant and Equipment [Line Items]
Total	6,690	7,517
Construction in progress
Property, Plant and Equipment [Line Items]
Total	$ 18,504	$ 27,919

Property, Plant and Equipment, net - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 11,797	$ 15,540	$ 22,606	$ 30,570
Prepaid tooling costs
Property, Plant and Equipment [Line Items]
Amortization expense	$ 19	$ 30	$ 36	$ 62

Property, Plant and Equipment, net - Schedule of Long Lived Assets (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	$ 219,294	$ 333,646
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	40,659	152,536
Philippines
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	127,274	106,618
Thailand
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	41,519	62,380
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	$ 9,842	$ 12,112

Goodwill and Intangible Assets - Summary of Changes in Carrying Amount of Goodwill (Details) $ in Thousands	6 Months Ended
	Sep. 25, 2020 USD ($)
Goodwill [Roll Forward]
43917	$ 1,285
Goodwill arising from acquisition	18,871
Currency translation	101
44099	$ 20,257

Goodwill and Intangible Assets - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Sep. 25, 2020	Mar. 27, 2020
Finite-Lived Intangible Assets [Line Items]
Gross	$ 54,986	$ 36,867
Accumulated Amortization	18,712	16,909
Net Carrying Amount	36,274	19,958
Patents
Finite-Lived Intangible Assets [Line Items]
Gross	30,801	29,115
Accumulated Amortization	11,066	9,834
Net Carrying Amount	$ 19,735	$ 19,281
Weighted- Average Lives	10 years	10 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross	$ 6,193	$ 5,462
Accumulated Amortization	5,797	5,335
Net Carrying Amount	$ 396	$ 127
Weighted- Average Lives	9 years	9 years
Process technology
Finite-Lived Intangible Assets [Line Items]
Gross	$ 17,150	$ 1,650
Accumulated Amortization	1,755	1,650
Net Carrying Amount	$ 15,395	0
Weighted- Average Lives	12 years
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross	$ 810	608
Accumulated Amortization	62	58
Net Carrying Amount	$ 748	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		6 Months Ended		12 Months Ended
	Aug. 28, 2020	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019	Mar. 27, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 20,257		$ 20,257		$ 1,285
Intangible assets amortization expense		$ 671	$ 418	$ 1,384	$ 845
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	18,871
Finite-lived intangible assets	13,600
Indefinite-lived intangible assets acquired	$ 2,400

Goodwill and Intangible Assets - Future Amortization Expense (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2021	$ 1,584
2022	3,057
2023	2,917
2024	2,788
2025	2,598
Thereafter	23,330
Net Carrying Amount	$ 36,274	$ 19,958

Other Assets, net (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
VAT receivables long-term, net	$ 4,988	$ 3,039
Deposits	2,376	2,399
Prepaid contracts long-term	3,609	1,282
Deferred offering costs	1,806	0
Other	2,000	2,090
Total	$ 14,779	$ 8,810

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Payables and Accruals [Abstract]
Accrued management incentive (LTIP)	$ 748	$ 11,488
Accrued management incentive (non-LTIP)	7,176	6,273
Accrued salaries and wages	18,105	12,069
Base acquisition purchase price due	17,244	0
Accrued vacation	5,804	7,146
Accrued severance	4,417	6,065
Accrued professional fees	4,258	4,036
Accrued income taxes	1,324	3,408
Accrued utilities	666	1,114
Other current liabilities	5,187	5,256
Total	$ 64,929	$ 56,855

Management Long-Term Incentive Plan (Details) $ in Thousands	6 Months Ended
	Sep. 25, 2020 USD ($)
Current Liabilities
Balance at the beginning of the period	$ 11,488
Balance at the end of the period	748
Long-Term Liabilities
Balance at the beginning of the period	2,439
Balance at the end of the period	$ 0
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)
Removal due to divestiture	(378)
Accruals	(270)
Balance at the end of the period	748
Long-Term Liabilities
Balance at the beginning of the period	2,439
Reclassification	(1,004)
Payments	0
Removal due to divestiture	(398)
Accruals	(1,037)
Balance at the end of the period	$ 0

Bank Lines of Credit (Details)				1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
Bank Lines of Credit (Details)	Mar. 18, 2020 USD ($)	Jan. 22, 2019 USD ($)	Mar. 27, 2006 USD ($)	Mar. 31, 2020 USD ($)	Mar. 27, 2020 USD ($)	Sep. 25, 2020 USD ($)	Mar. 27, 2020 USD ($)	Nov. 26, 2019 PHP (₱)	Nov. 20, 2019 PHP (₱)	Dec. 05, 2001 USD ($)
Line of Credit Facility [Line Items]
Bank lines-of-credit					$ 43,000,000	$ 33,000,000	$ 43,000,000
COVID-19
Line of Credit Facility [Line Items]
Proceeds from lines of credit				$ 43,000,000	43,000,000
Line of Credit
Line of Credit Facility [Line Items]
Bank lines-of-credit						$ 33,000,000
Line of Credit \| Line-of-Credit Agreement Expiring January 22, 2021
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
Line of Credit \| Line-of-Credit Agreement Due at Various Times During Fiscal Year 2021
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%
Line of Credit \| Line-of-Credit Agreement Maturing June 18, 2020
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	$ 8,000,000
Interest rate at period end					1.90%		1.90%
Line of Credit \| Line-of-Credit Agreement Expiring August 31, 2021
Line of Credit Facility [Line Items]
Maximum borrowing capacity						1,235,000		₱ 60,000,000
Outstanding balance					$ 0	0	$ 0
Interest rate at period end					4.60%		4.60%
Line of Credit \| Line-of-Credit Agreement Expiring June 30, 2021
Line of Credit Facility [Line Items]
Maximum borrowing capacity						1,544,000			₱ 75,000,000
Outstanding balance					$ 0	$ 0	$ 0
Line of Credit \| London Interbank Offered Rate (LIBOR) \| Line-of-Credit Agreement Expiring January 22, 2021
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.40%
Line of Credit \| London Interbank Offered Rate (LIBOR) \| Line-of-Credit Agreement Due at Various Times During Fiscal Year 2021
Line of Credit Facility [Line Items]
Basis spread on variable rate			1.00%

Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Other Liabilities Disclosure [Abstract]
Accrued management incentive (LTIP)	$ 0	$ 2,439
Accrued management incentive (non-LTIP)	1,012	2,304
Accrued retirement	9,213	8,005
Accrued contingent consideration	7,800	0
Provision for uncertain tax positions (net)	2,952	2,855
Other	274	275
Total	$ 21,251	$ 15,878

Retirement Plans - Schedule of Expense Related to Defined Benefit Plan (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 277	$ 238	$ 547	$ 475
Interest cost	156	168	308	334
Expected return on plan assets	(74)	(82)	(152)	(164)
Net acquired/transferred obligation	0	0	0	0
Amortization of net transition asset	0	(3)	0	(6)
Amortization of prior service cost	2	2	4	4
Actuarial loss	45	24	79	48
Net periodic pension expense	$ 406	$ 347	$ 786	$ 691

Retirement Plans - Fair Value of Entity's Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	Sep. 25, 2020	Mar. 27, 2020
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	$ 6,694	$ 5,579
Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	2,554	2,467
Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	2,408	1,992
Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,732	1,120
Government securities
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,862	1,260
Government securities \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,862	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	1,098	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	1,098	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	605	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	605	756
Bonds
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	1,309	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	1,309	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	1,820	1,572
Stocks and other investments \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets of non-U.S. defined benefit plan	692	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	$ 1,127	$ 364

Retirement Plans - Schedule of Changes in Fair Value of Level 3 Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	$ 5,579
Ending balance	6,694
Loans
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	756
Ending balance	605
Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Beginning balance	1,120
Ending balance	1,732
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	120
Redemptions during the year	(303)
Revaluation of equity securities	0
Change in foreign currency exchange rates	32
Ending balance	$ 605
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		745
Change in foreign currency exchange rates		18
Ending balance		$ 1,127

Retirement Plans - Narrative (Details) £ in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Sep. 25, 2020 GBP (£)	Mar. 27, 2020 USD ($)	Mar. 27, 2020 GBP (£)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 247	$ 230	$ 487	$ 463
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	1,053		$ 1,053		£ 827	$ 975	£ 866
Accrued retirement, other long-term liabilities	1,053		$ 1,053		£ 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	1,040	960	$ 2,069	2,007
Defined Contribution Plan \| AME Plan
Defined Benefit Plan Disclosure [Line Items]
Total contributions	$ 206	183	$ 385	359
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		$ 401		$ 934
Vesting percentage			100.00%
Safe Harbor Provision, employer contribution			0.03

Commitment and Contingencies (Details) - USD ($)	Sep. 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 Income per Share - Schedule of Computation of Net Income per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Earnings Per Share [Abstract]
Net income attributable to Allegro MicroSystems, Inc.	$ 9,584	$ 11,565	$ 14,404	$ 14,749
Net income attributable to common stockholders, basic	9,618	11,583	14,472	14,818
Net income attributable to common stockholders, diluted	$ 9,618	$ 11,583	$ 14,472	$ 14,818
Weighted average basic and diluted common shares (in shares)	10,000,000	10,000,000	10,000,000	10,000,000
Basic and diluted net income attributable to Allegro MicroSystems, Inc. per share (in dollars per share)	$ 0.96	$ 1.16	$ 1.44	$ 1.47
Basic and diluted net income attributable to common stockholders per share (in dollars per share)	$ 0.96	$ 1.16	$ 1.45	$ 1.48

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669619-108580

Reference 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 4: 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(22))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 6: 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 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669625-108580

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

+ References

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+ Details

Net Income per Share - Narrative (Details) - Common Stock, Class A - Common Stock	6 Months Ended
	Sep. 25, 2020
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%

Net Income per Share - Unaudited Pro Forma Net Income per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Numerator:
Net income, as reported	$ 9,584	$ 11,565	$ 14,404	$ 14,749
Denominator:
Weighted-average shares used to compute net income per share attributable to common shareholders, basic (in shares)	10,000,000		10,000,000
Pro forma adjustments to reflect the Common Stock Conversion (in shares)	156,500,000		156,500,000
Pro forma adjustments to reflect the Company’s buy-back of shares to cover withholding taxes (in shares)	(2,068,234)		(2,068,234)
Weighted average basic common shares (in shares)	164,431,766		164,431,766
Weighted average diluted common shares (in shares)	164,431,766		164,431,766
Pro forma basic net income per share attributable to common shareholders (in dollars per share)	$ 0.06		$ 0.09
Pro forma diluted net income per share attributable to common shareholders (in dollars per share)	$ 0.06		$ 0.09

Common Stock and Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
	Oct. 31, 2017 USD ($) class $ / shares shares	Sep. 25, 2020 $ / shares shares	Sep. 27, 2019 shares	Jun. 26, 2020 shares	Mar. 27, 2020 $ / shares shares	Jun. 28, 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, Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized (in shares)	12,500,000	12,500,000			12,500,000
Common stock, par value (in dollars per share) \| $ / shares	$ 0.01	$ 0.01			$ 0.01
Issuance of common shares (in shares)	6,720,000
Number of shares issued in transaction (in shares)	2,880,000
Net proceeds \| $	$ 291
Estimated offering costs \| $	$ 9,260
Priority dividend, percentage	0.08
Grants in period (in shares)	400,000
Vesting period	60 months
Common stock, shares outstanding (in shares)		10,000,000			10,000,000
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)		10,000,000	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	1,000,000			1,000,000
Common stock, par value (in dollars per share) \| $ / shares	$ 0.01	$ 0.01			$ 0.01
Grants in period (in shares)	597,400
Vesting period	4 years
Common stock, shares outstanding (in shares)		638,298			622,470
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)		15,828	0
Shares issued during period, weighted average price per share (in dollars per share) \| $ / shares		$ 33.83
Common stock, shares outstanding (in shares)		638,298	607,620	638,298	622,470	607,620	607,620
Common stock, shares outstanding, weighted average price per share (in dollars per share) \| $ / shares		$ 11.99

Common Stock and Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	$ 580	$ 374	$ 1,025	$ 748
Cost of sales
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	53	45	150	90
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	32	26	53	45
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	$ 495	$ 303	$ 822	$ 613

Income Taxes - Schedule of Tax Provision (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)
Income Tax Disclosure [Abstract]
Operating taxes	$ 1,589	$ 2,566	$ 2,405	$ 4,277
Discrete tax items	493	267	205	5,891
Provision for income taxes	$ 2,082	$ 2,833	$ 2,610	$ 10,168
Annual operating tax rate	0.136	0.178	0.141	0.171
Effective tax rate	17.80%	19.70%	15.30%	40.70%

- Definition

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

+ References + Details

Income Taxes - Narrative (Details) $ in Millions	6 Months Ended
Income Taxes - Narrative (Details) $ in Millions	Sep. 27, 2019 USD ($)
Income Tax Disclosure [Abstract]
Settlement of IRS transfer pricing audits	$ 5.5

Related Party Transactions (Details) $ in Thousands			1 Months Ended	3 Months Ended				6 Months Ended		12 Months Ended
Related Party Transactions (Details) $ in Thousands	Oct. 14, 2020 USD ($)	Mar. 28, 2020 USD ($)	Sep. 30, 2017 USD ($) shares	Sep. 25, 2020 USD ($)	Jun. 26, 2020 USD ($)	Sep. 27, 2019 USD ($)	Jun. 28, 2019 USD ($)	Sep. 25, 2020 USD ($)	Sep. 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				$ 136,649		$ 163,240		$ 251,650	$ 315,683
Trade accounts receivable from related party				16,394				16,394		$ 30,293
Amounts due to related party				1,157				1,157		4,494
Related party notes payable, less current portion				0				0		17,700
Current portion of related party debt				0				0		25,000
Noncash or part noncash divestiture, amount of consideration received								0	0
Trade accounts payable				23,856				23,856		20,762
Trade accounts receivable, net				57,926				57,926		59,457
Cost of goods sold				74,879		94,634		134,179	187,690
Eliminations
Related Party Transaction [Line Items]
Trade accounts receivable, net		$ 3,368
Cost of goods sold				1,760				1,198
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
Noncash or part noncash divestiture, amount of consideration transferred		$ 15,000
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%
Related party debt		$ 66,377
Note receivable from related party				51,377				51,377
Interest payable				762				762
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| PSL \| PSL \| Subsequent Event
Related Party Transaction [Line Items]
Interest paid	$ 762
Repayments of related party notes receivable	51,377
Related Party Revenue
Related Party Transaction [Line Items]
Total net sales				22,511		16,625		46,131	32,792
Distribution of Sanken products
Related Party Transaction [Line Items]
Total net sales				0		9,699		0	19,022
Sanken
Related Party Transaction [Line Items]
Trade accounts receivable from related party				11,654				11,654		30,293
Other accounts receivable from related party				389				389		558
Purchases from related party						8,569			16,479
Amounts due to related party										$ 4,494
Reimbursement of development costs						360			720
Promissory notes outstanding											$ 30,000
Stated interest rate											2.52%
Interest income									55
Number of notes payable \| notesPayable										3
Related party notes payable, less current portion										$ 17,700
Number of line-of-credit agreements \| lineOfCredit										2
Basis spread on variable rate										1.00%
Interest expense						383			795
Interest paid						730			754
Current portion of related party debt										$ 25,000
Sanken \| Related Party Revenue
Related Party Transaction [Line Items]
Total net sales				22,511		16,625		46,131	32,792
Sanken \| Distribution of Sanken products
Related Party Transaction [Line Items]
Total net sales						9,699			$ 19,022
PSL
Related Party Transaction [Line Items]
Trade accounts receivable from related party		$ 3,368		4,909				4,909
Purchases from related party				9,967				21,890
Amounts due to related party				1,157				1,157
PSL \| Subsequent Event
Related Party Transaction [Line Items]
Note receivable from related party	51,377
Repayments of related party notes receivable	$ 51,377
PSL \| Price Support Payment
Related Party Transaction [Line Items]
Purchases from related party				1,700				3,500
Director
Related Party Transaction [Line Items]
Monthly fee payable												$ 19	$ 30
Signing fee			$ 54
Severance payment if terminated			$ 180
Accelerated vesting, acceleration period			6 months
Related party transaction amounts				90	$ 90	$ 90	$ 90
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				$ 654				$ 654		$ 506

Subsequent Events - Narrative (Details)					1 Months Ended		3 Months Ended			6 Months Ended
Subsequent Events - Narrative (Details)	Nov. 02, 2020 USD ($) $ / shares shares	Oct. 14, 2020 USD ($)	Oct. 02, 2020 USD ($) shares	Sep. 30, 2020 USD ($)	Oct. 31, 2020 USD ($)	Oct. 31, 2017 USD ($) shares	Dec. 25, 2020 USD ($)	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Nov. 20, 2020 USD ($)
Subsequent Event [Line Items]
Stock-based compensation								$ 580,000	$ 374,000	$ 1,025,000	$ 748,000
Common Stock, Class A
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) \| shares						2,880,000
Net proceeds						$ 291,000
Estimated offering costs						$ 9,260,000
Grants in period (in shares) \| shares						400,000
Common Stock, Class L
Subsequent Event [Line Items]
Grants in period (in shares) \| shares						597,400
Subsequent Event
Subsequent Event [Line Items]
Shares issued upon conversion, including shares withheld for tax withholding obligation (in shares) \| shares	166,500,000
Shares issued upon conversion (in shares) \| shares	164,431,766
Subsequent Event \| RSU Conversion Program \| Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Grant date fair value (in dollars per share) \| $ / shares	$ 14.00
Subsequent Event \| LTIP \| RSU Conversion Program
Subsequent Event [Line Items]
Stock-based compensation	$ 607,000
Subsequent Event \| LTIP \| RSU Conversion Program \| Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Grants in period (in shares) \| shares	589,987
Subsequent Event \| TRIP \| RSU Conversion Program
Subsequent Event [Line Items]
Stock-based compensation	$ 421,000
Subsequent Event \| TRIP \| RSU Conversion Program \| Restricted Stock Units (RSUs)
Subsequent Event [Line Items]
Grants in period (in shares) \| shares	348,999
Subsequent Event \| Term Loan Facility \| Credit Suisse AG, Cayman Islands Branch
Subsequent Event [Line Items]
Maximum borrowing capacity				$ 325,000,000								$ 325,000,000
Subsequent Event \| Term Loan Facility \| Credit Suisse AG, Cayman Islands Branch \| Forecast
Subsequent Event [Line Items]
Repayments of line-of-credit agreement							$ 300,000,000
Subsequent Event \| Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd
Subsequent Event [Line Items]
Maximum borrowing capacity				50,000,000
Subsequent Event \| Line-of-Credit Agreement \| Mizuho Bank, Ltd
Subsequent Event [Line Items]
Repayments of line-of-credit agreement				25,000,000
Subsequent Event \| Line-of-Credit Agreement \| Bank Of Mitsubishi UFJ
Subsequent Event [Line Items]
Repayments of line-of-credit agreement				$ 8,000,000
Subsequent Event \| PSL
Subsequent Event [Line Items]
Note receivable from related party		$ 51,377,000
Repayments of related party notes receivable		$ 51,377,000
Subsequent Event \| Common Stock, Class A
Subsequent Event [Line Items]
Shares issued upon conversion (in shares) \| shares	156,155,403
Conversion rate	15.822
Shares returned for tax payments made on behalf of holders of common stock (in shares) \| shares	2,066,468
Stock-based compensation	$ 40,440,000
Aggregate cash dividend					$ 400,000,000
Subsequent Event \| Common Stock, Class L
Subsequent Event [Line Items]
Shares issued upon conversion (in shares) \| shares	8,276,363
Conversion rate	13.010
Shares returned for tax payments made on behalf of holders of common stock (in shares) \| shares	1,766
Outstanding loan amounts extinguished			$ 753,000
Stock-based compensation	$ 1,593,000
Accelerated vesting, percentage	0.25
Stock repurchased during period (in shares) \| shares			1,997
Stock repurchased during period, aggregate purchase price			$ 408,000
Subsequent Event \| IPO
Subsequent Event [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	$ 320,849,000
Underwriting discounts	20,125,000
Estimated offering costs	$ 9,026,000
Subsequent Event \| IPO \| Allegro Microsystems, Inc.
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) \| shares	25,000,000
Subsequent Event \| IPO - Selling Shareholders
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) \| shares	3,750,000

Subsequent Events - Schedule of Stock Issued in Common Stock Conversion (Details) - Subsequent Event	Nov. 02, 2020 shares
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	164,431,766
Shares of Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	163,972,017
Shares of Unvested Restricted Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	459,749
Common Stock, Class A
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	156,155,403
Common Stock, Class A \| Shares of Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	156,155,403
Common Stock, Class A \| Shares of Unvested Restricted Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	0
Common Stock, Class L
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	8,276,363
Common Stock, Class L \| Shares of Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	7,816,614
Common Stock, Class L \| Shares of Unvested Restricted Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	459,749

Label	Element	Value
Restricted Cash and Cash Equivalents	us-gaap_RestrictedCashAndCashEquivalents	$ 5,385,000
Restricted Cash and Cash Equivalents	us-gaap_RestrictedCashAndCashEquivalents	3,514,000
Restricted Cash and Cash Equivalents	us-gaap_RestrictedCashAndCashEquivalents	6,354,000
Restricted Cash and Cash Equivalents	us-gaap_RestrictedCashAndCashEquivalents	$ 5,188,000