中圖分類號(hào)： TM933 文獻(xiàn)標(biāo)識(shí)碼： A DOI：10.16157/j.issn.0258-7998.222584 中文引用格式： 李爽玉，馮榮尉，賈冬宇. 直流微電流測(cè)量的研究進(jìn)展[J].電子技術(shù)應(yīng)用，2022，48(7)：13-18. 英文引用格式： Li Shuangyu，F(xiàn)eng 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
Li Shuangyu，F(xiàn)eng Rongwei，Jia Dongyu
Beijing Orient Institute of Measurement and Test，Beijing 100094，China
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
