电子器件2018，Vol.41Issue(2)：431-436,6.DOI:10.3969/j.issn.1005-9490.2018.02.030
一种具有较大电容动态测量范围的接口电路
An Interface Circuit with Large Capacitance Dynamic Measuring Range
摘要
Abstract
In order to solve the problem of signal acquisition of capacitive sensor,a high precision capacitive sensor interface circuit with large dynamic range is proposed. The interface circuit is composed of a capacitor active bridge circuit and relaxation ossillator which can convert capacitor into frequency directly,and a frequency output circuit which is used to determine the response of the micro humidity sensor. Based on the capacitive humidity film sensor it was tested,the experimental results show that compared with the existing similar circuit design,the capacitance measurement range of the circuit structure is more simple and has greater and higher accuracy,in 1 pF~600 pF measuring range accuracy(error percent)<-2.14%,the interface circuit sensitivity is 4.91. Hz/10-6,and the output frequency and capacitance change with a linear relationship.关键词
电容式传感器/有源电桥/张弛振荡器/湿度测量Key words
capacitive sensor/active bridge/oscillator/humidity measurement分类
信息技术与安全科学引用本文复制引用
徐忠根,马永斌..一种具有较大电容动态测量范围的接口电路[J].电子器件,2018,41(2):431-436,6.基金项目
河南省科技厅2016年科技发展计划科技攻关重点项目(62102210361) （62102210361）
