A New Stray-Immune Interface Circuit for Capacitive Sensors
一种新的不受寄生电容影响的电容式传感器接口电路

A novel interface circuit is presented to detect the minimal change of the differential capacitance.Based on the charge transfer circuit,the interface circuit introduces another charge transfer circuit detecting the reference differential capacitance.By differentially amplifying the output of the detecting and reference circuit,the interface circuit shows better stability and much higher sensitivity.At the same time,it keeps the characteristic of high immunity to parasitic capacitance.