The circuit design for extraction of electro encephalogram signals

The design of front-end signals acquisition circuit is made for extraction of EEG signals, thus making it possible to amplify, filter, and remove the interference of source signal collected from the brain electrode. After the signal go in turn through such links as pre-amplification, high-pass filtration, 50Hz wave trapping, low-pass filtration, and post amplification, the EEG signals average amplitude of 50μV can reach to between 1V ~4V, thereby meeting the range of requirements the conventional acquisition card needs for the input of analog signal. The simulation results show that the signal, as collected through the circuit, are low in distortion, and thus can be widely used in the devices for processing EEG signals.