<DOCUMENT>
<TYPE>EX-21.1
<SEQUENCE>17
<FILENAME>b65742amexv21w1.txt
<DESCRIPTION>EX-21.1 LIST OF SUBSIDIARIES
<TEXT>
<PAGE>
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                                                                    EXHIBIT 21.1

                           ALLEGRO MICROSYSTEMS, INC.
                              LIST OF SUBSIDIARIES

<TABLE>
<CAPTION>
                                                          JURISDICTION OF
NAME OF SUBSIDIARY:                               INCORPORATION OR ORGANIZATION:
-------------------                               ------------------------------
<S>                                               <C>
Allegro MicroSystems Europe, Ltd.                 United Kingdom
Allegro MicroSystems Philippines, Inc.            Philippines
Allegro MicroSystems Philippines Realty, Inc.     Philippines
Allegro MicroSystems Argentina S.A.               Argentina
Allegro MicroSystems Business Development, Inc.   Delaware
</TABLE>
</TEXT>
</DOCUMENT>