OB2276

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 protection, and VDD under voltage lockout (UVLO). It also provides latch shut down mode protection include fixed/adjustable VDD over voltage protection (OVP), over temperature protection (OTP) and output over voltage protection. Excellent EMI performance is achieved with On-Bright proprietary frequency shuffling technique. The tone energy at below 22KHZ is minimized in the design and audio noise is eliminated during operation. OB2276 is offered in SOP8 package. FEATURES ■ Power on Soft Start Reducing MOSFET Vds Stress ■ Frequency shuffling for EMI ■ Extended Burst Mode Control For Improved Efficiency and Minimum Standby Power Design ■ Audio Noise Free Operation ■ Fixed 65KHZ Switching Frequency ■ Compre...