A Matching Technique for Biphasic Stimulation Pulse

Biphasic pulses are commonly used for neural stimulation. One of the important requirements for biphasic pulses is to maintain charge balance. Since the durations of the cathodic and anodic current pulses are usually set to the same value, the amplitudes of these current pulses are therefore required to be matched. In this paper, a self-calibration technique is proposed to match the amplitudes of the cathodic and anodic current pulses. For pulse amplitude of ~3mA, the amplitude difference between the two pulses can be reduced to less than 2μA after calibration.