Author(s)

Haiwei Mu, Chunhui Zhu

Corresponding Author

Chunhui Zhu

Abstract

In the field of plant electrophysiological signal measurement, it is necessary to accurately measure very weak current signals, usually ranging from 10-1 to 10-15A. However, it is very difficult to directly measure the distribution characteristics of plant electrophysiological signals. In this paper, a non-contact weak current detection system is designed by system proportional measurement method, focusing on the research and improvement of the measurement circuit itself. In order to overcome the disadvantages of expensive instruments, large size and the inability of chips to directly measure current, a circuit which can be applied to the weak current vector detection of sensors is designed. We chose the operational amplifier current feedback method to design the circuit, improved the circuit design and reasonably determined the circuit parameters, and finally realized the automatic continuous monitoring of multi-channel plant physiological electrical signal parameters with a measurement accuracy of 1nA

Keywords

Plant physiological electrical signal, System scale measurement, Weak current measurement, Circuit design, Simulation