The PR779 is a 1.2 kW universal input (85 to 270 VRMS) interleaved PFC converter with 390 VDC output. It achieves efficiencies greater than 95% at 115 Vac from 20% to 100% load. Efficiency is greater than 97% for the same load group when input is 230 Vac. Power factor is greater than 0.98 for the same load range and either 115 VAC or 230 VAC input. The design meets current EN61000-3-2 requirements. The design consists of two boards. The main board, PR779, includes the power train components and a daughter board, PR780. The daughter board contains all the necessary control circuitry to drive the power train. The control is based on the UCC28070 continuous current mode interleaved PFC controller.