Power Integrations LYT6079C-H129 | Demoboard DER-857

Description

This engineering report describes an isolated flyback LED driver. It is designed to drive a nominal LED voltage string of 24 V at 2.7 A through a constant current post regulator from an input voltage range of 90 VAC to 132 VAC. The LED driver utilizes the LYT6079C from the LYTSwitch-6 family of devices, which has a higher current limit than the usual LYT6079C part.DER-857 is a low-line input flyback converter design added with a switched valley-fill PFC circuit. Through the PFC circuit, the design meets the high power factor requirement in LED lighting application while reducing loss by direct energy transfer. The key design goals were high efficiency and high power factor across the input voltage range.This document contains the power supply specification, schematic diagram, bill of materials, transformer documentation, printed circuit board layout, and performance data.

Features

• Accurate constant voltage and constant current regulation
• Industry first AC/DC controller with isolated, safety rated feedback without optocoupler
• High power factor, >0.9 at 120 VAC
• Ultrafast transient response
• Highly energy efficient, >88 % across line
• Integrated protection and reliability features
• Output short-circuit protection
• Line and output OVP
• Thermal foldback and over temperature shutdown with hysteretic automatic power recovery
• CCM + quasi-resonant switching for precision CC/CV operation without need for loop compensation
• Meets IEC 2.5 kV ring wave, 1 kV differential surge
• Meets EN55022 conducted EMI

Typical applications

• LED Lighting

More information

• Datasheet
• IC product information