开关电源的过载保护电路设计  

Design of Over Load Protection Circuit for Switching Mode Power Supply

作　　者：刘雪山[1] 杨静[1] 张鸿儒[2] 

机构地区：[1]西南交通大学电气工程学院,四川成都610031 [2]西南交通大学信息科学与技术学院,四川成都610031

出　　处：《通信电源技术》2009年第4期45-48,共4页Telecom Power Technology

摘　　要：基于UC3842的反激式开关电源,文中从原理和实验两方面分析了恒功率控制和恒电流控制的过载保护电路,阐述了各自的特点,并提出了一种适用于短暂过载场合的延时锁定关断过载保护电路,实验证明此电路工作于保护模式时开关元件无开关应力,为高峰值负载电源过载保护电路的设计提供了一种有效的方法。Based on fly-back converter with UC3842 controlled, overload protection circuits of constant power control and constant current control are analyzed from principle and experiment result. The characteristics of these two overload protection circuits are presented. A kind of timer latch protection circuit used for transient overload is proposed. Experiment results verify that switching components do not have switching stress in protection mode, which provides an effective method to design protection circuit for switching mode power supply with high peak load.

关 键 词：开关电源 打嗝模式 开关应力 锁定保护 

分 类 号：TN86[电子电信—信息与通信工程] TM46[电气工程—电器]