基于Multisim8的RC一阶电路时间常数的测量  

The measurement on the time constant of first-order RC circuit with Multisim8

作　　者：张学文[1] 司佑全[1] 

机构地区：[1]湖北师范学院物理与电子科学学院,湖北黄石435002

出　　处：《湖北师范学院学报（自然科学版）》2013年第4期80-83,共4页Journal of Hubei Normal University(Natural Science)

基　　金：湖北师范学院2011年指导性教研项目(ZD201121)

摘　　要：在用示波器进行RC一阶电路时间常数τ的测量时,通常采用时标法测量输入信号脉冲宽度大于5τ情况下的时间常数,而当脉冲宽度小于5τ时,采用时标法比较困难。通过分析RC一阶电路充放电过程,得到τ=(T/2)/ln(U01/U01),再利用Multisim8读出U02,U01,进而准确算出电路时间常数τ,从而克服了在脉冲宽度小于5τ的情况下应用时标测量法存在的困难。For measuring the RC circuit＇s time constant with an oscilloscope , the time constant τ, which input signal pulse width is greater than 5τ, is usually measured using the method of time scale However , when the pulse width is less than 5τ, there is some difficulty if applying time scale method .In the present article , by analyzing the charge and discharge process of the first-order RC circuits, the authors obtain the formula τ=（T/2）/ln（Uo2/Uo1）.Then, find the value Uo2,Uo1 by use of Multisim8, and accurately calculate the time constant of the circuit , and so, overcome difficulty in applying the method of time scale measurement when the pulse width is less than 5τ.

关 键 词：RC串联电路 暂态过程 时间常数 

分 类 号：TN707[电子电信—电路与系统]