基于单片机的微小电阻测量系统设计  

Design of a micro resistance measuring instrument based on singlechip

作　　者：杨秀增 宋俊慷 韦树贡 YANG Xiuzeng;SON Junkang;WEI Shugong(Department of Physical and Electronic Engineering,Guangxi Normal University for Nationalities,Chongzuo 532200,China)

机构地区：[1]广西民族师范学院物理与电子工程学院,广西崇左532200

出　　处：《电子设计工程》2021年第2期85-89,共5页Electronic Design Engineering

基　　金：广西重点研发计划项目(2018AB44049);广西民族师范学院服务地方经济社会发展专项项目(2018FW004)。

摘　　要：针对利用电桥平衡法测量微小电阻,操作流程复杂和繁琐的问题,以STC15单片机为控制器,设计一款高精度、多档与自动微小电阻测量系统。测量系统主要由恒流源电路、电压信号预处理电路、数据采集与单片机控制4部分组成。恒流源电路采用高精度基准电压芯片LM399进行设计。采用高精度运放芯片ICL7650进行前置放大电路设计,利用有源二阶低通滤波器滤除高频干扰信号。采用四线制电阻测量法提高测量精度,采用可编程放大电路实现微小电阻的多档自动化测量。利用毫欧级标准电阻对系统进行测试,测试表明,该系统具有测量精度高、操作简便、读数直观等优点。In view of the complicated and complicated operation of measuring micro-resistance by bridge balance method,a high-precision micro-resistance measurement system was designed.The measuring system is composed of constant current source circuit,voltage signal preprocessing circuit,data acquisition and single chip microcomputer control.The constant current source circuit is designed by high precision voltage reference chip LM399.High-precision op-amp chip ICL7650 is used for pre-amplifier circuit design.An active second-order low pass filter is used to filter out interference signals.The four-wire resistance measurement method is adopted to improve the measurement accuracy,and the programmable amplifier circuit is used to realize the automatic measurement of micro resistance.The system is tested with milliohm standard resistance.The system has the advantages of high measurement accuracy,simple operation and intuitive reading.

关 键 词：微小电阻 四线制测电阻 可编程放大电路 STC15单片机 

分 类 号：TN98[电子电信—信息与通信工程]