WS3252

WS3252 WS3252 High Precision CC/CV Primary-Side PWM Controller Features ■ 5uA ultra-low startup current ■ 2mA Low operating current ■±5% Constant Voltage Regulation at Universal AC input ■ Primary-side Sensing and Regulation Without TL431 and Opto-coupler ■ Programmable CV and CC Regulation ■ Built-in Primary winding inductance compensation ■ Programmable cable drop compensation ■ Built-in soft start ■ Built-in Leading-edge blanking ■ Cycle by cycle over current protection (OCP) ■ VCC over voltage clamp & under voltage lockout( UVLO) ■ Maximum Gate output voltage clamped at 12V ■ Frequency jittering General Description WS3252 is a high-integrated offline PWM controller, optemized for high poformance low power AC/DC charger and adapter adapter application. WS3252 operates in primary-side sensing and regulation. Consequently, opto-coupler and TL431 could be eliminated, thus reduce the cost. It can achieve ± 5% constant voltage precision in full input voltage range. CC/CV Control as shown in fig.1.In CC Control, the current and output power setting can be adjusted externally by the sense resistor Rs at CS pin. In CV control, multi-mode operations are utilized to achieve high performance and high efficiency. In addition, good load regulation is achieved by the built-in cable drop compensation. Device operates in PFM in CC mode as well at large load condition and it operates in PWM with frequency reduction at light/medium load. Vo Applications Low power AC/DC offline SMPS for ...