DER-528 - 14 W non-dimmable, high efficiency (>86%), power factor corrected, isolated LED driver

This engineering report describes a non-dimmable, isolated flyback LED driver designed to drive 20V to 40V LED strings at 350mA over an input voltage range of 90VAC to 265VAC. The LED driver uses LYT5226D in the LYTSwitch-5 series of devices. LYTSwitch-5 is a non-dimmable LED driver IC with single-stage PFC functionality and precise LED current control. LYTSwitch-5 integrates a high-voltage power MOSFET and a discontinuous mode, variable frequency, variable on-time controller. The controller also offers fast (cycle-by-cycle) current limiting, input and output OVP, and advanced thermal management circuitry. The DER-528 provides a nominal 350 mA constant current output over a 20 V minimum – 40 V maximum output LED voltage range. Key design goals are high efficiency and constant current regulation over a wide input and output voltage range. This document contains power supply specifications, schematics, bill of materials, transformer documentation, printed circuit layout, design spreadsheet, and performance data.