This part is a kind of semiconductor called TB2903HQ.

Function of this product has Maximum Power 47 W BTL x 4-Ch Audio Power IC.

Manufacturers : Toshiba

Image and pinout :

Some of the text within the PDF file :

TB2903HQ TOSHIBA Bi-CMOS Digital Integrated Circuit Silicon Monolithic TB2903HQ Maximum Power 47 W BTL × 4-ch Audio Power IC The TB2903HQ is 4-ch BTL audio amplifier for car audio applications. This IC can generate higher power: POUT MAX = 47 W as it includes the pure complementary P-ch and N-ch DMOS output stage. It is designed to yield low distortion ratio for 4-ch BTL audio power amplifier, built-in standby function, muting function, and various kinds of protectors. Additionally, Off-set detector is built in. Weight: 7.7 g (typ.) Features • High power output : POUT MAX (1) = 47 W (typ.) (VCC = 14.4 V, f = 1 kHz, JEITA max, RL = 4 Ω) : POUT MAX (2) = 43 W (typ.) (VCC = 13.7 V, f = 1 kHz, JEITA max, RL = 4 Ω) : POUT (1) = 29 W (typ.) (VCC = 14.4 V, f = 1 kHz, THD = 10%, RL = 4 �� [ ... ]

TB2903HQ PDF Datasheet Download