电阻测量方法的研究

The Research on Measuring Method of Resistance

详细分析了1kΩ～500GΩ电阻各量程的分辨率和测量电路输出信号范围，并以此为依据设计了实用的电路系统。同时给出具体的测量方法如下：首先判断电阻的范围，将放大器切换到合适的量程；放大后的电压信号经A／D转换送给单片机计算电阻值；根据各自量程的标准电阻值及其测量值之差进行动态校正。该方法消除了噪声对测量精度的影响。测试结果表明：在全量程范围内，最小测量误差为0.03％，最大测量误差为0.8％。

The resolution and output signal of each range from 1 kΩ to 500 GΩ resistance are analyzed. Thus the practical circuit system is designed. The concrete measuring method is given as follows： Firstly, the unknown resistance range is judged approximately; then, switch the amplifier to an appropriate measurement range; the voltage signal output from amplifier is transmitted to single chip computer through A/D converter, the resistance value is calculated by the computer. Dynamic adjustment is conducted on the difference between the standard resistance of each range and the measurement. This method eliminates the noise effect on precision of measurement. Test results in full measurement rangeshow that the minimum measurement error is 0.03%, the maximum error is 0.8%.