Patent ID: 8095221

Claim:
An implantable pulse generator for generating electrical pulses for stimulation of tissue of a patient, the implantable pulse generator comprising: a controller; pulse generating circuitry for generating electrical pulses, the pulse generating circuitry comprising (i) a voltage multiplier for providing a plurality of voltages for pulse generation and (ii) at least one variable resistance circuit disposed in a circuit path of the pulse generating circuitry to control a magnitude of a respective electrical pulse; switching circuitry for delivering electrical pulses from the pulse generating circuitry to outputs of the implantable pulse generator; and output capacitors disposed between the switching circuitry and the outputs of the implantable pulse generator; the controller, controlling the pulse generating circuitry and the switching circuitry, to repeatedly generate consecutive first and second pulses to stimulate tissue of a patient using each first pulse and to discharge residual charge left on one or more output capacitors by each first pulse with each second pulse, wherein the controller controls the voltage multiplier to provide a lower voltage and controls the at least one variable resistance circuit to provide a lower resistance for each second pulse relative to each first pulse; wherein the voltage multiplier comprises a plurality of outputs including at least one constant voltage output and at least one variable voltage output.