OB2252 Datasheet | On-Bright

Current Mode PWM Controller for BJTFreq Shuffling GENERAL DESCRIPTION OB2252 is offered in SOT23-6, SOP-8 and DIP-8 packages. OB2252 is a highly integrated current mode PWM control IC optimized for high performance, low Features standby power and cost effective off-line flyback converter applications in sub 10W range. PWM frequency is internal constant and it is trimmed e to tight range. At no load or light load condition, the IC operates in ‘Extended burst mode’ to minimize fid switching loss. Lower standby power and higher conversion efficiency is thus achieved. VDD low startup current and low operating current a contribute to a reliable power on startup design with OB2252. A large value resistor could thus be used in n the startup circuit to minimize the standby power. o The internal slope pensation improves system large signal stability and reduces the possible sub- B harmonic oscillation at higher than 50% PWM duty cycle output. Leading-edge blanking on current to sense(CS) input removes the signal glitch due to snubber circuit diode reverse recovery and thus l greatly reduces the external ponent count and system cost in the design. tia OB2252 offers plete protection coverage with automatic self-recovery feature including Cycle-by Cycle current limiting (OCP), over load protection n (OLP), VDD over voltage clamp and under voltage lockout (UVLO). Excellent EMI performance is e achieved with On-Bright proprietary frequency shuffling technique together with soft switching fid control at the totem pole Base drive output. The tone energy at below 20KHZ is minimized in the n design and audio noise is eliminated during operation. - Optimized for sub 10W Application Driving Power BJT - Soft Start with 4 m S - Frequency Shuffling for Improved EMI - Extended Burst Mode Control For Improved Efficiency and Minimum Standby Power Design - Audio Noise Free Operation - Fixed 50KHZ Switching Frequency - Internal Synchronized Slope pensation - Low VDD...