Design of a neural stimulator system with closed-loop charge cancellation

The safety of electrode-tissue interface under electrical neural stimulation is a critical matter and thus precise control of the electrode voltage needs to be warranted. Analytical study on the electrode potential profile during electrical stimulation justifies the need of using a closed-loop system to regulate the electrode voltage. A neural stimulator with cancellation of excessive charge is proposed. The design procedure and methodology are presented to provide general guidelines for similar system designs. Simulation results demonstrate that neural stimulation safety can be achieved by the proposed design methodology.