This part is a kind of semiconductor called UPC1237.

Function of this product has PROTECTOR IC.

Manufacturers : UTC

Image and pinout :

Some of the text within the PDF file :

UNISONIC TECHNOLOGIES CO., LTD UPC1237 Preliminary LINEAR INTEGRATED CIRCUIT PROTECTOR IC FOR STEREO POWER AMPLIFIER „ DESCRIPTION UTC UPC1237 is a semiconductor integrated circuit designed for protecting stereo power amplifiers and loudspeakers. „ FEATURES * Wide supply voltage range of 25V~60V. * Contain a relay driver. (Max. I6=80mA) * Work as either latching function or automatic resetting function by using pin 3. (In both overload detection and output offset detection, either function can be selected.) * Single power supply. * Built-in output offset detection function. Both positive and negative output offset can be detected through pin2. * AC voltage can be detected. * Time delay function. The time delay form amplifier power ON to relay ON can be freely set by selecting extern [ ... ]

UPC1237 PDF Datasheet Download