一种基于UC3842的新型开关稳压电源设计  

Switching power supply based on UC3842

作　　者：衡耀付[1] 陈富军[1] 

机构地区：[1]黄淮学院电子科学与工程系,河南驻马店463000

出　　处：《电力自动化设备》2009年第9期133-136,共4页Electric Power Automation Equipment

基　　金：河南省科技厅科技攻关计划项目(2007140010)~~

摘　　要：设计了一种以电流型PWM控制器UC3842芯片为核心的高频单端反激式开关稳压电源。基于信号流程和电路功能模块划分,利用三端稳压器TL431配合新器件UC3842实现了对电源电压的控制和稳压输出。分析了新型开关电源的设计原理、各组成模块的功能以及工作过程。为了满足设计电源的电磁兼容性和安全性要求,设计利用低通滤波扼制了传导干扰,采用光耦器件PC817实现了输入/输出的隔离和反馈,并在电源电路中加入了热敏电阻、压敏电阻以及过压、过流保护等保护措施。实验测试结果表明:所设计的电源具有稳压性能优良,纹波小,电压调整率、负载调整率高等优点。A high frequency single- ended flyback switching power supply is designed with current- mode PWM controller UC3842 chip as its core. Based on the signal flow and functional circuit modules,the voltage control and stable output are realized by using three-terminal voltage regulator TL431 with the new device UC3842. Its design principle,module functions and working process are analyzed. In order to meet the requirements of electromagnetic compatibility and safety,the low- pass filter is used to restrain the conducted interference,and the optical coupler PC817 is used to realize the input/output isolation and feedback. The over-vohage and over-current protective measures are taken and the thermistor and varistor are added in power supply circuitry. Test results show that the designed power supply has good voltage regulation performance, with small ripple and high regulation rate of voltage and load.

关 键 词：开关电源 电流型PWM控制器 电压调整 负载调整 UC3842 电磁兼容性 传导干扰 

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