Charge Balancing Circuit, Stimulator Circuit and Method for Charge Balancing

A stimulator circuit for functional electrical stimulation, the stimulator circuit comprising:

• a charge balancing circuit comprising an electrode terminal configured to receive an electrode voltage, an amplifier coupled to the electrode terminal and configured to amplify and invert the electrode voltage to generate an intermediate voltage, and a compensation stage implemented as a transistor stage with a first transistor, the compensation stage configured to generate, when the electrode voltage lies outside a specified safety range and depending on the intermediate voltage, an output current by controlling a conductance the first transistor, and to supply the output current to the electrode terminal for driving the electrode voltage towards and/or into the specified safety range;
• and
• a stimulation source connected to the electrode terminal of the charge balancing circuit, wherein the stimulation source is implemented as a current source and is configured to supply a monophasic and/or a biphasic current pulse to the charge balancing circuit via the electrode terminal.