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    CONFORMED SUBMISSION TYPE:	S-1/A
    PUBLIC DOCUMENT COUNT:		26
    FILED AS OF DATE:		20201013
    DATE AS OF CHANGE:		20201013

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    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			ALLEGRO MICROSYSTEMS INC
    		CENTRAL INDEX KEY:			0000866291
    		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
    		IRS NUMBER:				000000000
    		FISCAL YEAR END:			0331

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    		SEC ACT:		1933 Act
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    		FILM NUMBER:		201236420

    	BUSINESS ADDRESS:
    		STREET 1:		115 NORTHEAST CUTOFF
    		CITY:			WORCESTER
    		STATE:			MA
    		ZIP:			01606
    		BUSINESS PHONE:		508-853-5000

    	MAIL ADDRESS:
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    		CITY:			WORCESTER
    		STATE:			MA
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