A circuit for providing a regulated output voltage from a charge pump circuit (51) while utilizing very low amounts of power, the circuit including a clock circuit (55) for providing clock pulses to operate the charge pump circuit to produce an output voltage, a bias circuit (54, 56-60) for monitoring the output voltage of the charge pump and furnishing signals for enabling the clock circuit in response to an insufficient output voltage, and circuitry (63-67, 69) for enabling the bias circuit during a fraction of the tool operating time available to the charge pump.