This part is a kind of semiconductor called TDA7850A.
Function of this product has 4 x 50 W MOSFET quad bridge power amplifier plus HSD.
Manufacturers : STMicroelectronics
Image and pinout :
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TDA7850A 4 x 50 W MOSFET quad bridge power amplifier plus HSD Features ■ High output power capability: – 4 x 50W/4Ω max. – 4 x 30W/4Ω @ 14.4V, 1KHz, 10% – 4 x 80W/2Ω max. – 4 x 55W/2Ω @ 14.4V, 1KHz, 10% Excellent 2Ω driving capability Hi-fi class distortion Low output noise St-by function Mute function Automute at min. supply voltage detection Low external component count: – Internally fixed gain (26dB) – No external compensation – No bootstrap capacitors On board 0.35A high side driver ■ ■ MOSFET output power stage ■ ■ ■ ■ ■ ■ ■ Flexiwatt27 (vertical) Flexiwatt27 (horizontal) ■ ESD Protections: ■ ■ ■ ■ ■ ■ ■ Output short circuit to GND, to Vs, across the load Very inductive loads Overrating chip temperature [ ... ]