United States securities and exchange commission logo January 28, 2021 Ravi Vig Chief Executive Officer Allegro Microsystems, Inc. 955 Perimeter Road Manchester, New Hampshire 03103 Re: Allegro Microsystems, Inc. Draft Registration Statement on Form S-1 Submitted January 25, 2021 CIK No. 0000866291 Dear Mr. Vig: This is to advise you that we do not intend to review your registration statement. We request that you publicly file your registration statement no later than 48 hours prior to the requested effective date and time. Please refer to Rules 460 and 461 regarding requests for acceleration. We remind you that the company and its management are responsible for the accuracy and adequacy of their disclosures, notwithstanding any review, comments, action or absence of action by the staff. Please contact Thomas Jones at 202-551-3602 with any questions. Sincerely, Division of Corporation Finance Office of Manufacturing cc: Peter M. Labonski, Esq.