DER-657 - 45 W High Power Factor, Isolated Flyback Switched Valley-Fill PFC LED Driver

This engineering report describes a 45 W isolated flyback power supply with a single-stage power factor correction circuit for LED lighting applications. This power supply is designed to provide a constant voltage of 80V on a 0A to 580mA output current load. It is also capable of providing a 580mA constant current output for LED lighting applications. The board is optimized to operate over an input voltage range of 90 VAC to 265 VAC. The DER-657 is a universal input flyback converter design with additional switching valley-fill PFC circuitry. Through the PFC circuit, the device meets the high power factor requirements found in LED lighting applications while reducing losses by transferring energy directly to the output. Key design goals are excellent regulation, high efficiency, and high power factor over the input voltage range. This document contains power supply specifications, schematics, bill of materials, transformer documentation, printed circuit board layout, and performance data.