Patent ID: 7113006

Claim:
A capacitor circuit, comprising: at least first and second capacitors, a first terminal of the first capacitor connecting to a first source providing a first voltage, a first terminal of the second capacitor connecting to a second source providing a second voltage, the first voltage being greater than the second voltage; a voltage comparator including a first input for receiving a voltage representative of the first voltage, a second input for receiving a third voltage provided by a third source, and at least one output for generating at least one control signal, the at least one control signal being a function of a difference between the voltage representative of the first voltage and the third voltage; and a switch connected to second terminals of the first and second capacitors, the switch being selectively operable in one of at least a first mode and a second mode in response to the control signal, wherein in the first mode the switch is operative to connect the first and second capacitors together in parallel, and in the second mode the switch is operative to connect the first and second capacitors together in series, the first mode being indicative of the voltage representative of the first voltage being less than or about equal to the third voltage, and the second mode being indicative of the voltage representative of the first voltage being greater than the third voltage.