<SEC-DOCUMENT>0001193125-21-032354-index.html : 20210208
<SEC-HEADER>0001193125-21-032354.hdr.sgml : 20210208
<ACCEPTANCE-DATETIME>20210208161232
ACCESSION NUMBER:		0001193125-21-032354
CONFORMED SUBMISSION TYPE:	424B4
PUBLIC DOCUMENT COUNT:		3
FILED AS OF DATE:		20210208
DATE AS OF CHANGE:		20210208

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALLEGRO MICROSYSTEMS, INC.
		CENTRAL INDEX KEY:			0000866291
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				462405937
		FISCAL YEAR END:			0331

	FILING VALUES:
		FORM TYPE:		424B4
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-252667
		FILM NUMBER:		21601543

	BUSINESS ADDRESS:	
		STREET 1:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103
		BUSINESS PHONE:		(603) 626-2300

	MAIL ADDRESS:	
		STREET 1:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALLEGRO MICROSYSTEMS INC
		DATE OF NAME CHANGE:	19900730
</SEC-HEADER>
<DOCUMENT>
<TYPE>424B4
<SEQUENCE>1
<FILENAME>d112873d424b4.htm
<DESCRIPTION>424B4
<TEXT>
Document 1 - file: d112873d424b4.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>2
<FILENAME>g112873g05f05.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 2 - file: g112873g05f05.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>3
<FILENAME>g112873g06h06.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 3 - file: g112873g06h06.jpg

</DOCUMENT>
</SEC-DOCUMENT>