具有零偏补偿功能的电容式微加速度计接口电路  

Interface circuit with zero compensation function for capacitive microaccelerometers

作　　者：刘民杰[1] 池保勇[2] 刘云峰[1] 董景新[1] 赵长德[1] 

机构地区：[1]清华大学精密仪器与机械学系,精密测试技术及仪器国家重点实验室,北京100084 [2]清华大学微电子学研究所,北京100084

出　　处：《清华大学学报（自然科学版）》2010年第11期1815-1819,共5页Journal of Tsinghua University(Science and Technology)

基　　金：国家“十一五”预研项目(5130805020.8)

摘　　要：为了实现了电容式传感器和其他信号处理电路之间的接口,提出了一种电容式传感器接口电路。该接口电路基于开关电容技术,采用采样电荷结构,并在其前端读出电路采用采样开关噪声消除技术,在0.35μm 2P-4 M CMOS标准工艺下设计并流片实现,且特别适用于开环或力平衡闭环电容式微加速度计和振动角速度陀螺仪应用。测试结果表明:在1 MHz的采样时钟下,该接口电路取得了约5.35 aF的电容分辨率和约0.173 aF.Hz-1/2的噪声基底。This paper presents an interface circuit that provides an interface between capacitive MEMS sensors and other signal processing circuits.The interface circuit was based on the switched-capacitor technique,with the sample-charge architecture.The sampling switch KT/C noise elimination technique was used in the front-end readout circuit.The specially designed interface circuit was implemented for applications in open-loop and force-balance close-loop capacitive accelerometers and vibratory rate gyroscopes in a standard 0.35-μm 2P-4M CMOS process.Experimental results indicate that the interface circuit achieves about 5.35 aF of capacitance resolution with a 1 MHz sampling rate and has a rough noise floor of 0.173 aF/rt-Hz@152 Hz at ambient atmosphere.

关 键 词：微加速度计 接口电路 开关电容 采样电荷 噪声基底 

分 类 号：TH824.4[机械工程—仪器科学与技术]