硅压阻压力传感器调理电路设计与验证  

Design and Certification of Conditioning Circuit for Silicon Piezo-resistive Pressure Sensors

作　　者：王浩 张弛 赵建平 WANG Hao;ZHANG Chi;ZHAO Jian-ping(School of Civil Aviation,Northwestern Polytechnical University,Xi'an 710072,China;Aeronautical Computing Technique Research Institute,Aviation Industry Corporation of China,Xi'an 710065,China)

机构地区：[1]西北工业大学民航学院,陕西西安710072 [2]中国航空工业集团公司西安航空计算技术研究所,陕西西安710065

出　　处：《仪表技术与传感器》2022年第11期7-11,共5页Instrument Technique and Sensor

基　　金：航空科学基金(2018ZC31003)。

摘　　要：文中提出了一种硅压阻压力传感器的调理电路。首先,针对硅压阻压力传感器精度取决于激励源的特性,提出了一种高精度直流电压激励电路,该激励电路采用负反馈结构,且具有过流保护功能,当外部发生过流故障时,恒压源输出变为占空比可配置的PWM形式,有效提高了电路可靠性;其次,针对硅压阻压力传感器输出阻抗较大的问题,利用传感器全桥结构提出了“双上拉电阻”方案,在实现开路检测功能的同时,对硅压阻压力传感器输出误差影响可忽略不计,并设计了基于仪表运放的放大电路及滤波电路;最后,对该电路进行了测试验证,结果表明激励电压精度为0.2%,传感器输出调理精度为0.5%,满足压力高精度调理需求。A conditioning circuit of silicon piezo-resistive pressure sensor was proposed.First, aiming at that the accuracy of the silicon piezo-resistive pressure sensor depends on the accuracy of the excitation source, a high precision DC voltage excitation circuit was proposed, which adopted a negative feedback structure, and the circuit had the function of over-current protection.When the external over-current fault occurred, the output of the circuit became PWM form with duty cycle, and the reliability of the circuit was improved effectively.Secondly, in view of the large output impedance of silicon piezo-resistive pressure sensor, the scheme of "double pull-up resistance" was put forward by utilizing the full bridge structure of the sensor, while realizing the open-circuit detection function, the influence on the output error of the silicon piezo-resistive pressure sensor was negligible, and the amplifier circuit and the filter circuit based on the instrument operational amplifier were designed.Finally, the circuit was tested and verified.The results show that the excitation voltage error does not exceed 0.2%, and the sensor output adjustment error does not exceed 0.5%, which meets the requirements of high-precision pressure adjustment.

关 键 词：硅压阻压力传感器 调理电路 精密电压源 开路检测 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]