摘要
介绍了对数放大器测量电流的方法,使用高阻抗的场效应晶体管作为反馈元件,设计了一种宽范围微弱电流的测量电路。选择具有极低输入偏置电流和失调电压的运放提高测量的精度;选择匹配的结型场效应管和热敏电阻实现温度补偿。仿真结果表明,该电路的测量范围为100pA～10mA,测量精度高。
A method of measuring current of logarithmic amplifier is introduced.Using the highimpedance Junction Fieldeffect Transistor as a feedback component,a wide range of weak current measuring circuit has been designed.With very low in put bias current and offset voltage operation amplifier to improve the measurement accuracy;JFET which is matched and thermistors for temperature compensation are selected.Simulation results show that the measurement range of the circuit is lOOpAlOmA, with a high accuracy.
出处
《工业控制计算机》
2013年第6期130-131,共2页
Industrial Control Computer
关键词
输入电流
对数放大器
仿真
input current
logarithmic amplifier
simulation
