A low-noise charge sensitive amplifier for MEMS capacitive sensors

Author

Wang, Zhanfei ; Li, Zhihong ; Ni, Xuewen ; Mo, Bangxian

Author_Institution

Inst. of Microelectron., Peking Univ., Beijing

fYear

2006

fDate

23-26 Oct. 2006

Firstpage

673

Lastpage

675

Abstract

This paper describes a low-noise charge sensitive amplifier (CSA) for MEMS capacitive sensors which uses a chopper technique to reduce the low-frequency noise and offset. The feedback resistors of the CSA are implemented as a MOS-bipolar pseudo-resistors and an input common-feedback (ICMFB) is designed to prevent large output errors from input common-shift and maintain the op-amp within its input common-mode range. A simulated resolution of 5.8aF (rms) in capacitive change integrated over the signal band is achieved while chopped at 1 MHz

Keywords

MOSFET; capacitive sensors; choppers (circuits); low noise amplifiers; microsensors; operational amplifiers; 1 MHz; MEMS capacitive sensors; MOS-bipolar pseudoresistors; charge sensitive amplifier; chopper technique; feedback resistors; input common-feedback; low-noise amplifier; op-amp; Capacitance; Capacitive sensors; Choppers; Low pass filters; Low-frequency noise; Low-noise amplifiers; Micromechanical devices; Noise reduction; Operational amplifiers; Output feedback;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State and Integrated Circuit Technology, 2006. ICSICT '06. 8th International Conference on

Conference_Location

Shanghai

Print_ISBN

1-4244-0160-7

Electronic_ISBN

1-4244-0161-5

Type

conf

DOI

10.1109/ICSICT.2006.306433

Filename

4098203