A Stimulation Artifacts Removal Technique Employing VCO and Phase Detector for Simultaneous Neural Stimulation and Recording

In this paper, a voltage-controlled oscillator (VCO) and phase detector (PD) based stimulation artifact (SA) removal scheme is proposed for simultaneous neural stimulation and recording. VCO is used to avoid the saturation of conventional front-end amplifier. The VCO converted signals are separated in the frequency and time domain. A PD in closed- loop recovers the neural signal from the converted signal, and a predicted SA amplitude helps removing the SA. Compared to other SA removal schemes, the proposed VCO-PD-based SA removal technique avoids the subtraction path at the input stage to ensure a high input impedance and achieves high linearity for continuous SA removal.