Exhibit 99.1 Allegro MicroSystems Reports Second Quarter 2025 Results – Sales Increased 12% Sequentially to 187Million–Manchester,NH,October31,2024–AllegroMicroSystems,Inc.("Allegro"orthe"Company")(Nasdaq:ALGM),agloballeaderinpowerandsensingsemiconductorsolutionsformotioncontrolandenergyefficientsystems,todayannouncedfinancialresultsforitssecondquarterendedSeptember27,2024."Wedeliveredresultsin−linewithourcommitments.Secondquartersaleswere187 millio ...