Design of an electronic device for brain computer interface applications

This paper presents the design of an amplifier for EEG signals. The study of EEG signals is very important for the detection of cerebral rhythmic and any abnormalities. Brain waves are classified with respect to human activity; these signals represent an extremely low dynamic range (5 - 200 muV), in a frequency band of 0.5 - 40 Hz. Brain electrical potentials are acquired through the use of special surface electrodes, with a monopolar mounting: sensing electrode is placed over the skull of interest, while along the mid line a second electrode is positioned for reference electrode. This work describes the single electronic stage for the conditioning of the analog acquired signal. The final simulations of the whole electronic circuit are showed and a comparison with the devices on the market is reported.