This part is a kind of semiconductor called TEA2025A.

Function of this product has STEREO AUDIO AMPLIFIER.

Manufacturers : UTC

Image and pinout :

Some of the text within the PDF file :

UNISONIC TECHNOLOGIES CO.,LTD. TEA2025A LINEAR INTEGRATED CIRCUIT STEREO AUDIO AMPLIFIER  DESCRIPTION The UTC TEA2025A is a monolithic integrated circuit, consisting of a 2-channel power amplifier. It is suitable for stereo and bridge amplifier application of radio cassette tape recorders.  FEATURES * High output power Stereo: Po=2.3W (Typ) at Vcc=9V, RL=4 Ω Bridge: Po=4.7W (Typ) at Vcc=9V, RL=8Ω * Low switching distortion at high frequency * Small shock noise at the time of power on/off dur to a built-in muting circuit * Good ripple rejection due to a built-in ripple filter * Good channel separation * Soft tone at the time of output straiten * Closed loop voltage gain fixed 45dB (Bridge: 51dB) but availability with external resistor added * Minimum number of external part [ ... ]

TEA2025A PDF Datasheet Download