A Chopper Stabilized Pre-amplifier for Magnetic Sensor

Author

Jing, Zhao ; Shuang, Zhang ; Shudong, Chen

Author_Institution

Coll. of Electron. Sci. & Eng., Jilin Univ., Changchun, China

fYear

2012

Firstpage

501

Lastpage

504

Abstract

This paper introduced chopping principle and presented a design of chopper stabilized pre-amplifier for magnetic sensor. Compared with auto-zeroing technique, chopping technique does not fold noise to DC and the noise performance is better. This chopper stabilized pre-amplifier used the integrated instrumentation amplifier AD620 as the main amplifier. It achieved low voltage noise about 10nV/√Hz, and the corner frequency of 1/f noise about 1.5mHz. Residual offset caused by nonidealities of CMOS switch was reduced by a delayed demodulate clock. And the measured result was found to agree well with the simulated result.

Keywords

1/f noise; CMOS analogue integrated circuits; choppers (circuits); magnetic sensors; preamplifiers; 1/f noise; CMOS switch; auto-zeroing technique; chopper stabilized preamplifier; corner frequency; delayed demodulate clock; integrated instrumentation amplifier AD620; low voltage noise; magnetic sensor; noise performance; residual offset; Choppers (circuits); Clocks; Frequency modulation; Harmonic analysis; Magnetic sensors; Noise; Power harmonic filters; 1/f noise; chopper stabilized; magnetic sensor; pre-amplifier;

fLanguage

English

Publisher

ieee

Conference_Titel

Industrial Control and Electronics Engineering (ICICEE), 2012 International Conference on

Conference_Location

Xi´an

Print_ISBN

978-1-4673-1450-3

Type

conf

DOI

10.1109/ICICEE.2012.139

Filename

6322428