摘要
为克服电桥测量小电阻时存在的测量误差大、电桥的使用电流大等问题 ,提出了一种利用方波作为测量信号源 ,通过测量待测电阻上方波电压的方法来间接测量电阻值的方案 .方波信号源由运算放大器振荡电路提供 .本设计电路可以精确测量 0 .0 0 1Ω~ 1 .999Ω电阻 .
Inordertosolvetheproblemaboutbigerrorandbigelectrobridgeelectriccurrentwhenwe useelectrobridgetosurveylittleresistance ,thisarticleputsforwardaplanwhichusesthesquarewavesignal sourceandsurveystheresistancevalueindirectlybysurveyingthesquarewavevoltageontheresistance . Thesquarewavesignalsourceisproducedbyaoscillatorcircuitdesignedbytheoperationalamplifier .This circuitcansurveytheresistancevaluefrom 0 .0 0 1Ωto 1 .999Ωaccurately .