This part is a kind of semiconductor called TA8251AHQ.

Function of this product has MAX POWER 30W BTL x 4CH AUDIO POWER IC.

Manufacturers : Toshiba Semiconductor

Image and pinout :

Some of the text within the PDF file :

TA8251AHQ TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic TA8251AHQ Max Power 30W BTL × 4ch Audio Power IC The TA8251AHQ is 4ch BTL audio power amplifier for consumer application. It is designed low distortion ratio for 4ch BTL audio power amplifier, built−in stand−by function, muting function and junction temperature detection circuit. Additionally, the AUX. amplifier is built−in, it can make the beep signal etc. Output to 2 channels (out1 and 4). It contains various kind of protectors for car audio. Features • High power : POUT (max) = 30W (typ.) (VCC = 13.7V, f = 1kHz, RL = 4Ω) : POUT (1) = 21W (typ.) (VCC = 14.4V, f = 1kHz, THD = 10%, RL = 4Ω) Weight: 9.8g (typ.) • Low distortion ratio : THD = 0.02% (typ.) (VCC = 13.2V, f = 1kHz, POU [ ... ]

TA8251AHQ PDF Datasheet Download