Design of charge-sensitive and current-sensitive preamplifiers for electrostatic sensor

Abstract In this paper, the signal shape similarity degree is defined as quantitative criteria to distinguish charge-sensitive or current-sensitive preamplifier of electrostatic sensor. To establish the relationship between the similarity degree and the preamplifier, the rate (k) of the cutoff frequency of the preamplifier to the highest frequency of the induced current signal is presented. It is found that there are monotonic relationships between the similarity degree and k, which are built and used to design charge-sensitive and current-sensitive preamplifiers with different requirements. The results of the single particle free-fall experiment verify the effectiveness of this method.