This part is a kind of semiconductor called VIPER12A-E.
Function of this product has Low power offline switched-mode power supply primary switcher.
Manufacturers : STMicroelectronics
Image and pinout :
Some of the text within the PDF file :
VIPER12A-E Low power offline switched-mode power supply primary switcher Features ■ Fixed 60 kHz switching frequency ■ 9 V to 38 V wide range VDD voltage ■ Current mode control ■ Auxiliary undervoltage lockout with hysteresis ■ High voltage start-up current source ■ Overtemperature, overcurrent and overvoltage protection with auto-restart ■ Typical power capability – European (195 - 265 Vac) 8 W for SO-8, 13 W for DIP-8 – European (85 - 265 Vac) 5 W for SO-8, 8 W for DIP-8 Description The VIPER12A combines a dedicated current mode PWM controller with a high voltage power MOSFET on the same silicon chip. Figure 1. Block diagram SO-8 DIP-8 Typical applications cover off line power supplies for battery charger adapters, standby power supplies for TV or monitors, auxiliar [ ... ]