中图分类号： TM933
文献标识码： A
DOI：10.16157/j.issn.0258-7998.222584
中文引用格式： 李爽玉，冯荣尉，贾冬宇. 直流微电流测量的研究进展[J].电子技术应用，2022，48(7)：13-18.
英文引用格式： Li Shuangyu，Feng Rongwei，Jia Dongyu. Research on the progress of weak current detection[J]. Application of Electronic Technique，2022，48(7)：13-18.

Research on the progress of weak current detection

Abstract： DC micro current measurement technology is widely used in nuclear radiation detection, electrostatic detection, space radiation detection and other fields. It is a characteristic extreme value measurement technology, involving many technologies such as high impedance operational amplifier circuit design, leakage current protection and so on. The research on DC micro current measurement technology mainly starts with resistive and capacitive feedback circuits, analyzes the working principle and transfer function of the measurement circuit, focuses on the influence of leakage current, thermal potential, operational amplifier and resistance parameters on the measurement error, deduces the circuit transfer function and simulation analysis, and finally puts forward a scheme to reduce the influence of various parameters on the measurement results. This paper summarizes the DC micro current measurement methods at home and abroad in recent years, and analyzes the current voltage conversion method, current frequency conversion method and modulation, demodulation and amplification method. The current situation of DC micro current measuring instruments at home and abroad is investigated. There are many high-precision weak current measuring instruments in the world, which greatly improves the weak signal measurement.

Key words : weak current detection；preamplifier；I-V conversion；I-F conversion