自动电阻测试仪的设计及其误差处理

设计了一款宽范围自动量程转换电阻测试仪。以STC12C5A08S2为核心,通过继电器自动转换量程,由高阻抗运放LF356组成比例运算电路,得到不同的输出电压,经过单片机自带的10位ADC并通过换算得到被测电阻的阻值。详细分析了各量程的分辨率,提高测试精度的方法,并根据测试结果利用软件补偿硬件的方法使用曲线拟合的方式进行误差处理,在测试值和实际值之间建立方程来减小误差,最终测试结果表明各量程的最大测量误差为1%。具备使用方便,测量范围宽,精度高的特点。

Design and errortreatment of automatic resistance tester

Design of a wide range of automatic resistance tester is introduced.STC12C5A08S2 is used as the core,and the relay is used for automatic conversion range.By the high impedance op-amp LF356 composition proportion operation circuit,get different output voltage.By single chip with 10 ADC and the conversion,it can get tested resistance of the resister.This paper analyzes each range resolution,improves the accuracy of the test method.According to the test results,using software compensation method with curve fitting is used for error handling.equations are established between in the measured value and the actual value to reduce errors.Test results show that the range of the maximum error of measurement is 1%.The system is easy to use,and it has wide measuring range,and the characteristics of high precision.