Polarity detection base pulse insertion for active charge balancing in electrical stimulation

In this paper a previously published charge balancing method, namely pulse insertion, is improved to a new charge balancer which balances the injected charge based on the polarity detection. This makes the remaining voltage to be placed nearer to zero in comparison with the original pulse insertion. Therefore, the faradaic reactions are reduced due to the decrement of the remaining voltage on the double layer capacitor. The proposed charge balancer and the original pulse insertion charge balancer are designed in a 0.18 μm technology and their simulation results are compared. Finally, a discrete-component prototype of the proposed system is implemented to verify that this method is able to balance the charge with more precision.