Patent ID: 7233504

Claim:
A circuit for regulating a power supply, comprising: a switch coupled between first and second terminals, one of the first and second terminals to be coupled to an input of the power supply, the other of the first and second terminals to be coupled to an input of an energy transfer element of the power supply; an adjustment circuit to be coupled to a third terminal to receive a feedback signal representative of an output level of the power supply to cause a feedback state signal to be generated having a first feedback state that represents an output level that is above a threshold level and a second feedback state that represents an output level that is below the threshold level, the adjustment circuit to adjust the feedback state signal in response to at least one of adjusting the threshold level or adjusting the feedback signal, the adjustment to the feedback state signal tending to cause the feedback state signal to revert from a state at the time of adjustment to a state immediately preceding the adjustment; and a control circuit coupled to the switch and coupled to receive an oscillating signal and the feedback state signal, the control circuit to control switching of the switch in response to the oscillating signal and the feedback state signal.