An integrated MEG acquisition system with CMOS instrumentation amplifier and offset cancellation

Author

Lyu, HyunJune ; Choi, Jae Sung ; Choi, Hyun Jin ; Park, Gun Sang ; Han, Seung Soo ; Choi, Jun-rim

Author_Institution

Sch. of Electron. Eng., Kyungpook Nat. Univ., Daegu, South Korea

fYear

2012

fDate

19-21 Sept. 2012

Firstpage

81

Lastpage

84

Abstract

We propose a CMOS-based Magnetoencephalography(MEG) acquisition system. The MEG acquisition system consists of a small-sized high inductance coil sensor and an instrumentation amplifier (IA). The small-sized high inductance coil sensor is fabricated in 0.18 μm standard CMOS process. Output signal sensitivity of MEG acquisition sensor chip is 3.25fT/μV and noise figure of 34.9fT/(√Hz). The IA is designed along with low-pass and high-pass filters to reduce noise. It draws only 540 μA from a standard 3.3V battery, making it suitable for use in portable systems. By using current feedback techniques it achieves a common mode rejection ratio of 120 dB while the total noise referred to input is kept below 0.87 μV.

Keywords

CMOS analogue integrated circuits; biomedical electronics; high-pass filters; instrumentation amplifiers; low-pass filters; magnetoencephalography; CMOS instrumentation amplifier; MEG acquisition sensor chip; common mode rejection ratio; current 540 muA; current feedback techniques; high-pass filters; integrated MEG acquisition system; low-pass filters; magnetoencephalography acquisition system; offset cancellation; output signal sensitivity; portable systems; size 0.18 mum; small-sized high inductance coil sensor; standard CMOS process; voltage 3.3 V; CMOS integrated circuits; Coils; Inductance; Instruments; Magnetic field measurement; Superconducting magnets; Temperature measurement; Biomedical instrumentation amplifier; High inductance magnetic coil; Integrated sensor; Magnetoencephalogram(MEG);

fLanguage

English

Publisher

ieee

Conference_Titel

Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD), 2012 International Conference on

Conference_Location

Seville

Print_ISBN

978-1-4673-0685-0

Type

conf

DOI

10.1109/SMACD.2012.6339422

Filename

6339422