This part is a kind of semiconductor called STRV152.

Function of this product has PRC Off-Line Switching Regulator.

Manufacturers : Sanken electric

Image and pinout :

Some of the text within the PDF file :

Low Profile and Creeping distance of 4mm Package 650V, 2.8Ω, tOFF= 8µs, PRC Off-Line Switching Regulator STR-V152 General Descriptions The STR-V100 series comprise an integrated power MOSFET and a controller IC with a current mode and PRC* control for switching power supply applications. * PRC (Pulse Ratio Control)---the control method for OFF-time fixed and ON time controlled (Sanken’s designation) The SIP8L full mold package of low-profile and with creeping distance between high and low voltage of 4mm or longer (lead pin on Printed Circuit Board, PCB). A startup circuit and a standby function are incorporated in the control circuit. Thereby, requirements for low power consumption and low standby power can be achieved. The product easily achieves high cost-performance power supply sy [ ... ]

STRV152 PDF Datasheet Download