RDR-347 - 12.6 W, TRIAC Dimmable, Isolated Flyback, Power Factor Corrected (>0.97) LED Driver

This document describes an isolated high power factor (PF) TRIAC dimmable LED driver designed to drive a 34 V, 370 mA LED string over an input voltage range of 90 VAC to 132 VAC. The LED driver uses LYT4313E in the LYTSwitch IC series. The topology used is a single-stage power factor corrected flyback, which provides the high efficiency, high power factor, low THD, isolation, low component count and dimming performance required for this design. High power factor and low THD are achieved by using the LYTSwitch IC, which also provides a range of sophisticated protection features, including automatic restart for open control loop and output short-circuit conditions. Line overvoltage provides longer line fault and surge tolerance, and precise hysteretic thermal shutdown ensures safe average PCB temperatures are maintained under all conditions. Design documents include LED driver specifications, schematics, PCB diagrams, bill of materials, transformer documentation and typical performance characteristics.