用于MEMS微电容检测的全差分放大器  

Full Differential Amplifier for MEMS Micro-Capacitor Detecting

作　　者：江儒龙[1,2] 孔德义[1] 李庄[1,2] 鲍路路[1,2] 林丙涛[1,2] 郭攀[1,2] 

机构地区：[1]中国科学院合肥智能机械研究所传感器国家重点实验室,安徽省仿生感知与先进机器人技术重点实验室,合肥230031 [2]中国科学技术大学物理系,合肥230026

出　　处：《半导体技术》2009年第2期181-184,192,共5页Semiconductor Technology

基　　金：国家自然基金资助项目(60574093,50534050)

摘　　要：设计了一种用于MEMS电容传感器的低噪声低失调全差分运算放大器。微传感器传感电容一般很小,传感电容的变化更小。低噪声低失调放大器大大提高了整个传感器检测电路精度。该放大器采用连续时间共模反馈方法稳定共模输出、低阻结点斩波和动态匹配方法以期达到有稳定输出的低噪声低失调全差分放大器,给出基于HJTC 0.18μm CMOS 1P6M工艺的仿真结果,经过精心设计,各项指标达到或超过应用要求。A low noise low offset full differential amplifier for MEMS capacitor sensor was presented. The capacitor of the micro-sensor is always very small, and the change of the sensor capacitor is much smaller. So this amplifier can help the whole detecting-circuit behave much better. Continue-time CMFB circuit is used for stabilizing the common mode voltage of the amplifier, low noise and offset are achieved by using a chopper and dynamic element matching. The simulating result based on HJTC 0. 18 μm CMOS 1P6M technology is supplied and the results reach or beyond the demand.

关 键 词：微电子机械系统电容传感器 全差分运放 共模反馈 低噪声 

分 类 号：TN722[电子电信—电路与系统]