光电式甲醛监测系统中信号调理电路的设计  

Design of Signal Conditioning Circuit in Photo-electricity Inspecting System for Formaldehyde

作　　者：王元昊[1] 肖韶荣[1] 冒晓莉[1] 

机构地区：[1]南京信息工程大学电子与信息工程学院,江苏南京210044

出　　处：《仪表技术与传感器》2007年第11期55-57,共3页Instrument Technique and Sensor

基　　金：江苏省社会发展计划(BS2005054);高校产业发展计划(JHB04-009)

摘　　要：根据光电式甲醛检测原理和探测光束的特点,设计了光电式甲醛浓度测量传感器信号调理电路,该调理电路主要由光电探测器前置放大电路、窄带有源滤波器和精密交流信号-直流信号转换电路3部分组成。基于OP07运算放大器设计的交流信号-直流信号转换电路等效净输入信号小于0.3μV,降低了甲醛测试系统检测限,提高料测试精度。以此信号调理电路构成的系统,实验标定的甲醛浓度的检出限低于2μg/L.Signal conditioning circuit in photo-electricity sensor of measurement for formaldehyde concentration was designed based on inspecting principle formaldehyde and probing light beam. The conditioning circuit consists of photo-electricity detector pre-amplifier, narrowband fountainhead filter and precision AC/DC signal conversion circuit. The AC/DC signal conversion circuit was formed based on OP97 operation amplifier. Its equivalent import signal voltage is less than 0.3 μV. The measurement system inspection threshold is decreased, and the precision is improved. Experiment demarcation indicates that the inspection threshold is less than 2μg/L in the system of measurement for formaldehyde concentration.

关 键 词：光度测量术 甲醛传感器 调理电路 检测限 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]