The PMP20612 reference design is a high efficiency AC-DC LED driver reference design with very low total harmonic distortion (THD). This design uses CCM PFC with the UCC28180 controller to provide power factor correction (PFC) functionality from 108VAC to 305VAC input. A two-switch Flyback converter with the UCC28740 controller is used to provide 200V/1A constant current (CC)/ constant voltage (CV). The voltage sensing and current sensing circuit at the output side with the TL431 and INA180 allow an external circuit to process a dimming function. As a result this design achieves 92.9% peak efficiency at 230VAC/50Hz input. At 277VAC, the board also has less than 20% THD with 20% load.