Primary-Side Regulated Flyback with 184 to 265VAC Input (12V @ 3W) Reference Design

The PMP8764 reference design uses the UCC28700 primary-side regulated flyback controller to generate a 12V/250mA output from a 230VAC input. The valley switching of the UCC28700 allows this low-cost design to achieve a maximum load efficiency over 78%; no load losses are only 30mW.This circuit fits onto a 23mm x 37mm PCB.