This part is a kind of semiconductor called OB2273A.

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

Manufacturers : On-Bright

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OB2273A High Performance Current Mode PWM Controller GENERAL DESCRIPTION OB2273A 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 OB2273A. OB2273A offers complete protection coverage with auto-recovery including Cycle-by-Cycle current limiting (OCP), over load protection (OLP), VDD under volt [ ... ]

OB2273A PDF Datasheet Download