Conference Proceeding

A 28-μW EEG readout front-end utilizing a current-mode instrumentation amplifier and a source-follower-based LPF

Dept. of Biomed. Eng., Univ. of Macau, Macau, China
10/2010; DOI:10.1109/PRIMEASIA.2010.5604878 In proceeding of: Microelectronics and Electronics (PrimeAsia), 2010 Asia Pacific Conference on Postgraduate Research in
Source: IEEE Xplore

ABSTRACT A novel low-power EEG readout front-end featuring a current-mode instrumentation amplifier (CMIA) followed by a 4th-order gain-compensated source-follower-based lowpass filter (LPF) is proposed. The CMIA is of current-conveyor topology and is chopper-stabilized to improve the common-mode noise rejection and suppress the dc-offset and 1/f noise. The typical gain-loss problem of source-follower-based LPF is alleviated by adopting a gain-compensation technique. Optimized in 0.35-μm CMOS, the achieved CMRR is >100 dB from 0.01 to 16 Hz, and >90 dB up to 40 Hz. With the chopper stabilization, the noise voltage density is 248 nV√Hz at 0.01 Hz and 197 nV√Hz at 100 Hz. The power consumption is 28 μW at 3 V.

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