Non-Isolated 14 W LED Driver

This design example report describes a non-isolated 14 W LED driver employing TNY279GN for LED lighting application. It operates in an input voltage ranging from 195 VAC to 265 VAC and delivers an output of 20 V at 0.7 A. This design features high efficiency, integrated TinySwitch-III safety and reliability, BP/M capacitor value that selects MOSFET current limit for greater design flexibility, and tightly toleranced I2f parameter that reduces system cost.

The LED array and enclosure were designed to provide safety isolation to the end user. Therefore the output of this design is not electrically isolated from the AC input.

This document contains the complete specification of the power supply, a detailed circuit diagram, the entire bill of materials required to build the supply, the transformer design, the test data, and the oscillographs of the power supply’s most important electrical waveforms.