SN57CP Datasheet | On-Bright

DESCRIPTION SN57 is a high performance offline PSR power switch for low power AC/DC charger and adapter applications. It operates in primary-side sensing and regulation. Consequently, opto-coupler and TL431 could be eliminated. Proprietary Constant Voltage (CV) and Constant Current (CC) control is integrated as shown in the figure below. 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 pensation. 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. The chip consumes very low operation current, it can achieve less than 75m W standby power. SN57 offers prehensive protection coverage with auto-recovery features including Cycle-by-Cycle current limiting, VDD over voltage protection, short circuit protection, built-in leading edge blanking, VDD under voltage lockout (UVLO), OTP etc. SN57 is offered in SOP8 package. FEATURES - Primary-side sensing and regulation without TL431 and opto-coupler - High precision constant voltage and current regulation at universal AC input - Multi-mode PWM/PFM operation for efficiency improving - Quasi-resonant operation for highest overall efficiency - Programmable CV and CC regulation - Built-in line voltage and primary winding inductance pensation - Programmable cable drop pensation - No need for control loop pensation - Audio noise free operation - Internal BJT switch - Good dynamic response with synchronous rectifier application - Built-in leading edge blanking (LEB) - prehensive protection coverage with auto-recovery - VDD over voltage protection - VDD under voltage lockout with hysteresis (UVLO) - Cycle-by-cycle current limiting - Feedback loop open protection - Output short circuit protection - Over temperature...