SNVAA87
august 2023
LMR38020
1
Abstract
Trademarks
1
Introduction
1.1
Micro Inverter System
1.2
Typical Power Tree and Design Requirements
2
Conventional Flyback Design Challenges
2.1
SSR Design Challenges
2.2
PSR Design Challenges
3
New Fly-Buck Design
3.1
LMR38020 Overview
3.2
Comparison with Conventional Flyback
3.3
Design Considerations
3.4
LMR38020 Fly-Buck Design Example
4
Bench Test and Result
4.1
Start Up
4.2
Typical Switching Waveforms Under Steady State
4.3
Efficiency
4.4
Load Regulation
4.5
Short Circuit
4.6
Thermal Performance
5
Summary
6
References
6
References
Texas Instruments,
LMR38020 SIMPLE SWITCHER® 4.2-V to 80-V, 2-A Synchronous Buck Converter with 40-μA IQ
, data sheet.
Texas Instruments,
Designing an Isolated Buck (Fly-Buck™) Converter using the LMR38020
, application note.
Texas Instruments,
UCC28600 8-Pin Quasi-Resonant Flyback Green-Mode Controller
, data sheet.
Texas Instruments,
High-Efficiency Off-Line CV and CC Flyback Controller with Primary-Side Regulation (PSR)
, data sheet.
Würth Elektronik,
Lifetime of Optocouplers
E2E,
Differences between PSR and SSR in bias power-supply design
IEEE,
Isolated Bias Power Supply for IGBT Gate Drives Using the Fly-Buck Converter