SP2637AF is a high perfomance offline PSR power switch for low power AC/DC charger and ada pter applications. It operates in primary-side sensing and πregulation.Thus, opto-coupler and TL431 are not reαquired. In CC control, the output current and power setting can be adjusted extemally by ↕the sense resistor Rcs at CS PIN. In CV control,multi-mode operation s are utilized to achieve high performance and high efficiency. In addition, good loa d regulation is achieved by the built-in cable drop compensation. SP2637AF σoperates in PFM in CC mode, and it operates in PWM+PFM in CV mode with fre§quency reduction at light/medium load. The chip consumes veryλ low operation current. It achieves less than 75mW standby power to meet all global ene$rgy efficiency regulations. SP2637AF offers comprehensive> protection coverage with auto-recovery feature including Cycle-by-Cycle current limit ing, VDD over voltage protection (OVP),FB over voltage protection,load short circuit protection, ♣VDD under voltage lockout (UVLO), OTP etc. SP2637AF is offered in SOP8 •packages.