Patent ID: 7683596

Claim:
A circuit comprising: a DC/DC converter having an output and a trim input, wherein the trim input changes a first voltage at the output of the DC/DC converter; and a control circuit having a sense input coupled to the output of the DC/DC converter and an output coupled to the trim input, the control circuit comprising a comparator and an output control circuit, wherein the comparator receives a first signal corresponding to a reference voltage and a second signal corresponding to the first voltage at the output of the DC/DC converter, the comparator comparing the first and second signals, and the output control circuit having an input coupled to an output of the comparator and an output coupled to the trim input of the DC/DC converter, the output control circuit comprising: a capacitor, the capacitor storing a voltage; an amplifier having an input coupled to the capacitor and an output coupled to the trim input; a first current source selectively coupled to the capacitor to charge the capacitor; a second current source selectively coupled to the capacitor to discharge the capacitor; and control logic having an input coupled to an output of the comparator, the control logic controlling the first and second current sources to charge and discharge the capacitor to adjust the voltage on the trim input to reduce a difference between the first signal and the second signal, wherein the DC/DC converter and the control circuit are configured in a control loop.