A Multichannel EEG Acquisition Scheme Based on Single Ended amplifiers and Digital DRL

M. HABERMAN; E. SPINELLI

IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2012 vol. 6 p. 614 - 618

1932-4545

Abstract—Single ended (SE) amplifiers allow implementingbiopotential front-ends with a reduced number of parts, being wellsuited for preamplified electrodes or compact EEG headboxes.On the other hand, given that each channel has independent gain;mismatching between these gains results in poor common-moderejection ratios (CMRRs) (about 30 dB considering 1% tolerancecomponents). This work proposes a scheme for multichannel EEGacquisition systems based on SE amplifiers and a novel digitaldriven right leg (DDRL) circuit, which overcome the poor CMRRof the front-end stage providing a high common mode reductionat power line frequency (up to 80 dB). A functional prototype wasbuilt and tested showing the feasibility of the proposed technique.It provided EEG records with negligible power line interference,even in very aggressive EMI environments.