This offline flyback reference design uses the UCC28700 controller to generate 2 isolated outputs (12 V at 1.2 A, -3.3 V at 10 mA) from an AC input (85 VAC - 400 VAC). The controller provides accurate voltage and current regulation with primary-side feedback, eliminating the need for opto-coupler feedback circuits. The valley-switching technique reduces switching losses and keeps the efficiency high.
Features
- 85 VAC - 400 VAC input to 2 isolated outputs
- Valley-switching operation for high overall efficiency
- Primary-side regulation eleminates opto-coupler
- Precise control of output voltage and current