This part is a kind of semiconductor called BA5977FP.

Function of this product has 4ch BTL driver.

Manufacturers : Rohm

Image and pinout :

Some of the text within the PDF file :

IC CD BA5977FP BA5977FP CD 1 4ch BTL BA5977FP LSI PWM 4ch BTL ! CD/MD CD-ROM ! 1) 4ch BTL 2) HSOP28 3) 3ch PWM 4) ch4 SW 5) 6) 7) 8) 1 PreVCC=8V, PowVCC=8V, RL=8Ω , 5.4V Typ. ! Ta=25°C ! IC ! 28 27 Pre Vcc 26 25 24 23 22 10k 50k 100k PIN3 F R INTERFACE 100k R F THERMAL SHUTDOWN INTERFACE FR SW F RF INTERFACE FR R 12 345 67 BA5977FP 21 20 19 18 17 MUTE Vref 50k 50k Pow Vcc Ch3,4 Pow Vcc 19k 10k 50k 6.5k 50k PIN26 16 15 LEVEL SHIFT Pow Vcc Ch1, 2 8 9 10 11 12 13 14 IC ! BA5977FP IC ! ch1 3 4,6,23pin 17k 10k 20k 10k 11 18pin 20pin 50k 50k BA5977FP ch1 3 5,7,22pin 17k 7.3k 50k 9pin 50k 3pin 50k 50k 1pin 2pin 24pin 100k 100k 100k 25pin 10k 100k 27pin 50k 50k 26pin BA5977FP IC ! Ta=25°C, VCC=8V, RL=8Ω, Vb=VOP+=1.75V Parameter Symb [ ... ]

BA5977FP PDF Datasheet Download