A 700µW 8-channel EEG/contact-impedance acquisition system for dry-electrodes

A 700µW 8-channel active-electrode (AE) based EEG monitoring system is presented. The complete system consists of 9 AEs and a back-end analog signal processor. It is capable of continuously recording EEG signals and electrode-tissue contact impedance (ETI). The EEG channels have 1.2GΩ input impedance, 1.75µVrms noise (0.5–100Hz), 84dB CMRR, and can reject ±250mV of electrode offset, while consuming less than <87µW (including ETI measurement). The system facilitates ambulatory use and patient comfort, while delivering high quality EEG signals.