SY22657FAC - Single Stage buck-boost and PFC Regulator for LED Dimming application


  • Integreated 600V MOSFET
  • 5%~100% Dimming Range
  • Compatible with 500Hz ~5kHz PWM
  • Fast Start up, <500ms
  • Valley Turn-on of the Primary MOSFET to Achieve Low Switching Losses
  • Power Factor >0.90
  • Reliable Short LED and Open LED Protection
  • RoHS Compliant and Halogen Free
  • Compact Package: SO8

Typical Application


The SY22657 is a single stage buck-boost and PFC Regulator targeting at LED lighting application with analog dimming, which can achieve up to 5% dimming level, high precision for all loading range.

It adopts the proprietary control architecture to achieve an accurate regulation of LED current and Quasi-Resonant valley turn-on high efficiency operation. Proprietary self-bias technique saves the bias supply and reduces the startup time. It keeps the converter in constant on time operation to achieve high power factor.

Reliable short/open LED protection is integrated.


  • LED Lighting