Patent ID: 6750685
Filing Date: 2004-06-15
Classification: H03K,H03L

Abstract:
An apparatus, comprising:a first switch circuit that is actuated in response to a first control signal; a second switch circuit that is actuated in response to a second control signal; a first transistor that is arranged to conduct a first current when the first switch circuit is in an open position; a second transistor that is arranged to conduct a second current when the second switch circuit is in an open position; a capacitance circuit that is arranged to be charged in response to the first current, and to be discharged in response to the second current, wherein the capacitance circuit is arranged to provide an output voltage that corresponds to a charge stored therein, wherein the output voltage is held substantially constant when the first and second switch circuits are in a closed position, the output voltage increases when the first switch circuit is in an open position and the second switch circuit is in a closed position, and the output voltage decreases when the first switch circuit is in a closed position and the second switch circuit is in an open position; and a reset circuit that is arranged to adjust the output voltage at power up.