一种应用于微型气体流量计的低噪声信号采集系统  

A low noise signal acquisition system applied in micro gas flowmeter

作　　者：李辉[1] 刘鲲[1] 

机构地区：[1]安徽师范大学物理与电子信息学院,安徽芜湖241000

出　　处：《传感器与微系统》2012年第11期81-83,共3页Transducer and Microsystem Technologies

基　　金：安徽师范大学博士科研启动基金资助项目(132-151202)

摘　　要：针对微型气体流量计对微弱信号采集的要求,采用超低偏置电流的放大芯片LMP7721,辅以Guard环保护技术,再加上24位高精度A/D转换器ADS1211,设计了一种超高分辨率、低噪声的弱信号采集系统。通过将数字和模拟部分分开布局,以及合理的电源和地线设计,系统的性能得到了保证。实验表明:采集系统的最小可分辨信号接近0.1 mV,噪声RMS值小于50μV。Aiming at requirement of micro gas flowmeter on weak signal acquisition,super low offset current amplifier chip LMP7721 with Guard ring protection technology,and 24 bit A / D converter ADS1211 are used in the design.A super-high resolution and low noise weak signal acquisition system is designed.Performance of the system is guaranted,digital and analog part must be laid out separately,and power and ground wires also should be planned reasonably.The experiment shows the least resolved signal is close to 0.1 mV,and the noise RMS is less than 50 μV.

关 键 词：微型气体流量计 Guard环 高精度A D转换器 低噪声信号采集系统 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]