LED驱动器的反馈控制闭环电路分析
LED Driver Circuit of Control Closed Loop Analysis
毛竹1
作者信息
- 1. 卡任特照明(上海)有限公司,上海,201203
- 折叠
摘要
本文介绍以电流反馈的半桥开关控制驱动LED的实用电路.以半桥驱动作为主电路并用变压器作为隔离电路,同时以电阻作为负载LED的电流检测传感器以及放大器、光耦隔离作为负反馈回路.推导出每个子电路的传递函数,把所有子电路的传递函数集合成幅频特性和相频特性的表达式,利用MathCAD画出幅频特性和相频特性的波特图.通过调整电路元器件的参数,最终满足波特图稳定裕度判定方法来确定负反馈环路系统的稳定性.
Abstract
The article introduces a practical circuit for drive LED using half-bridge switch control with current feedback.A half-bridge driver is used as the main circuit and a transformer is used as an isolation cir-cuit.The resistor is used as the current detection sensor of the LED load,with amplifier and opt coupler isola-tion as a negative feedback loop.The transfer function set of all sub circuits is derived and synthesized into ex-pressions for amplitude frequency characteristics and phase frequency characteristics.MathCAD is used to draw Bode plots of amplitude-frequency characteristics and phase-frequency characteristics.By adjusting the parame-ters of circuit components,the Bode plot stability margin determination method is finally satisfaction.
关键词
半桥控制/负反馈环路/幅频和相频特性/MathCAD/波特图/稳定裕度Key words
half-bridge control/closed feedback loop/amplitude frequency and Phase frequency/Math-CAD/bode plot/stability margin引用本文复制引用
出版年
2024
NETL
NSTL
万方数据