This part is a kind of semiconductor called OB2276.

Function of this product has High Performance Current Mode PWM Controller.

Manufacturers : On-Bright

Image and pinout :

Some of the text within the PDF file :

OB2276 High Performance Current Mode PWM Controller GENERAL DESCRIPTION OB2276 is a highly integrated current mode PWM control IC optimized for high performance, low standby power and cost effective offline flyback converter applications. PWM switching frequency at normal operation is internally fixed and is trimmed to tight range. At no load or light load condition, the IC operates in extended ‘burst mode’ to minimize switching loss. Lower standby power and higher conversion efficiency is thus achieved. VDD low startup current and low operating current contribute to a reliable power on startup and low standby design with OB2276. OB2276 offers complete protection coverage with auto-recovery including Cycle-by-Cycle current limiting (OCP), over load protection (OLP), Brownout protectio [ ... ]

OB2276 PDF Datasheet Download