宽量程微电流测量系统  

Wide range weak current integrated amplifier

作　　者：周艳明[1] 谢中[1] 王祝盈[1] 王太宏[1] 陈小林[1] 李媛[1] 

机构地区：[1]湖南大学应用物理系,湖南长沙410082

出　　处：《物理实验》2006年第11期18-20,23,共4页Physics Experimentation

摘　　要：宽量程微电流测量系统利用多增益前置放大器与可编程增益数据采集卡组成两级放大，通过PC机控制选择不同增益实现宽量程的测量，并对其噪声进行了仿真分析，提出了提高信噪比的措施．实验表明，该系统能对动态范围10^11～10^-4A电流信号进行有效测量．The wide range weak current measurement system is a two level amptt/ter composed of multi-gain preamplifier and programmable data collection card. The wide rang measurement is realized through computer controlled gain selection. The noise characteristic of the preamplifier is analyzed by simulation, and the method of improving signal-to-noise is discussed. The experiment shows that this system can detect weak current effectively with the range from 10^-11 to 10^-4 A.

关 键 词：宽量程 微电流放大器 噪声 信噪比 

分 类 号：TM933.1[电气工程—电力电子与电力传动]