High-Precision and Low-Noise Readout Circuits for Wearable EEG-Signal Acquisition Devices

A high Precision and low noise gain-configurable 2-channel readout circuits, which enables the measurement of wearable electroencephalography (EEG) signal is presented in this article. The prototype readout circuits has been fabricated in a standard 0.18 μm BCDA process. Benefiting from the proposed low-power chopper amplifier structure that eliminates the need for an additional low-pass filter (LPF) and continuous optimization design, it achieves a common mode rejection ratio (CMRR) of -121.6 dB, an input-referred noise (IRN) of 0.42 μVpp , and a dynamic range (DR) of 129.6 dB. Compared with front-end for wearable EEG-Signal acquisition, the proposed work demonstrates an advanced DR (129.6 dB) and a competitive IRN (0.42 μVpp). The proposed gain-configurable 2-channel front-end was implemented in a wearable EEG-signal acquisition experiments to test brainwave responses under the typical low-frequency steady-state visual evoked potential paradigm (SSVEP), successfully demonstrating its capability for wearable EEG-signal acquisition.