低压系统中的过压欠压保护电路设计  

Design of over-voltage and under-voltage protection circuit in low-voltage system

作　　者：赵川粤 冯全源[1] 刘恒毓 Zhao Chuanyue;Feng Quanyuan;Liu Hengyu(Institute of Microelectronics,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学微电子研究所,成都611756

出　　处：《电子测量技术》2022年第7期88-92,共5页Electronic Measurement Technology

基　　金：国家自然科学基金重点项目(62090012,61531016,61831017);四川省科技支撑计划重点项目(2020YFG0282,2020YFG0028,2020YFG0452)资助。

摘　　要：设计了一种应用于低压系统的过压欠压保护电路,通过类似带隙基准的电路结构提高了输出电压阈值精度,通过减少二极管使用实现了低压条件适用,并在电路的欠压保护阈值门限电压中设计了一定迟滞量,防止系统在阈值附近反复关断,其电路的功能正确性在低压电源管理系统应用仿真中进行了验证。基于SMIC 0.18μm标准CMOS工艺,使用Cadence软件对电路进行了设计以及仿真。结果表明,在-40℃~85℃的温度变化区间内,电源电压上升时,系统开始正常工作电压阈值为2.431~2.50 V,阈值精度为3.2%;过压保护阈值为4.931~5.22 V,精度为5.7%;电源电压下降时,欠压检测阈值为1.58~1.663 V,精度为4.9%。系统应用仿真结果表明,在电源电压超出系统正常工作电压阈值时,过压欠压保护电路将控制系统进入关断模式,体现出了正确的保护功能。An overvoltage and undervoltage protection circuit for low-voltage systems is designed.The output voltage threshold accuracy is improved through a circuit structure similar to a bandgap reference,low-voltage conditions are achieved by reducing the use of diodes,and a certain hysteresis is designed in the undervoltage protection threshold voltage of the circuit to prevent the system repeatedly turning off near the threshold,and the functional correctness of the circuit is verified in the simulation of the low-voltage power management system application.The circuit is designed and simulated using SMIC 0.18μm standard CMOS process and Cadence software.The results show that when the power supply voltage rises within the temperature range of-40℃~85℃,the circuit starts to work normally and the voltage threshold is 2.431~2.50 V,the threshold accuracy is 3.2%,the overvoltage protection threshold is 4.931~5.22 V,the accuracy is 5.7%,when the power supply voltage drops,the undervoltage detection threshold is 1.58~1.663 V,the accuracy is 4.9%.The system application simulation results show that when the power supply voltage exceeds the normal operating voltage threshold of the system,the over-voltage and under-voltage protection circuit will control the system to enter the shutdown mode and realize the protection function.

关 键 词：低压系统 欠压保护 过压保护 阈值精度 

分 类 号：TN432[电子电信—微电子学与固体电子学]