飞安级微弱电流C、R测量法性能对比及改进  

Comparison and Improvement with the Capacity of C/R Measurement Method of fA Level Current

作　　者：张贵宇[1] 庹先国[1] 王洪辉[1] 奚大顺[1] 张兆义[1] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,成都610059

出　　处：《电测与仪表》2011年第12期8-12,共5页Electrical Measurement & Instrumentation

基　　金：国家杰出青年科学基金资助项目(41025015);地质灾害防治与地质环境保护国家重点实验室自主研究课题(SKLGP2009Z007);成都市科技计划(10GGYB323GX-023)

摘　　要：通过微弱电流电容积分法(C法)、跨阻法(R法)性能对比分析,得出C法适合间断测量、R法适合连续快速测量场合;以R法为例,从运算放大器选择、抗混叠滤波、高分辨率A/D转换、测量温度控制四个方面出发,解决了输入偏置电流、噪声干扰、分辨率低、环境温度变化等因素对微弱测量的影响,提高了测量性能,实现了对连续变化微弱电流的fA级测量。Through the comparative analysis of capacitor-integration and transimpedance measurement method of weak current,the paper can conclude that capacitor-integration method is suitable for discontinuous measurement,and transimpedance method is suitable for quickly continuous measurement.Taking transimpedance method for example,viewed from choosing amplifier,anti-aliasing filter and high resolution A/D conversion standpoint,the effect caused by input bias current,noise disturbance,low resolution and ambient on weak current measurement temperature has been solved,and improved the performance of measurement.Finally,it has been successful to measure the continuous variation current of fA level.

关 键 词：电容积分/跨阻法 fA(飞安)电流 抗混叠滤波 

分 类 号：TM935[电气工程—电力电子与电力传动]