Patent ID: 8144760

Claim:
A circuit for use with an analog signal and a predetermined value, comprising: a control circuit including a first comparator adapted to compare the analog signal and the predetermined value and configured to provide a control signal based on the comparison of the analog signal and the predetermined value; a sawtooth signal generating circuit coupled to the control circuit for receiving the control signal and configured to provide a sawtooth signal with a direction of ramp in the form of an up ramp or a down ramp, the direction of the ramp being based on the control signal; and a second comparator coupled to the sawtooth signal generating circuit and the control circuit, the second comparator receiving the analog signal and selectively receiving the up ramp or the down ramp of the sawtooth signal and the second comparator being configured to generate an output to the control circuit based on the analog signal and the direction of ramp of the sawtooth signal.