Patent ID: 8498132

Claim:
A control circuit for use in a power converter, comprising: a clock signal generator coupled to generate a clock signal to control switching of a power switch to be coupled to the control circuit, wherein the clock signal generator comprises a comparator coupled to hold an oscillator from oscillating in response to the feedback circuit; and a feedback circuit coupled to receive a feedback signal which is representative of an output of a power converter during a duration of an output power diode conduction time, the feedback circuit coupled to respond to the feedback signal to control the clock signal generator to regulate a ratio of the duration of the output power diode conduction time divided by a duration of a total power switch switching cycle period, wherein the feedback circuit comprises a detection circuit to determine the duration of the output power diode conduction time, wherein the detection circuit comprises a diode conduction detection circuit to detect when the output power diode is conducting current to determine the duration of the output power diode conduction time, and wherein the diode conduction detection circuit comprises a comparator coupled to compare the feedback signal with a threshold to detect when the output power diode is conducting current.