Patent ID: 8008903

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; a feedback circuit coupled to receive a feedback signal which is representative of an output of a power converter during a feedback portion of an off time of the power switch, the feedback circuit coupled to respond to the feedback signal to control the clock signal generator to regulate a duty cycle of the feedback portion of the off time of the power switch as a proportion of a total power switch switching cycle period, wherein the feedback circuit further comprises a feedback capacitor coupled to be charged during the feedback portion of the off time of the power switch and coupled to be discharged for a remaining portion of the total power switch switching cycle period and comprises first and second current sources coupled to charge and discharge the feedback capacitor; and a voltage stabilization circuit coupled to the feedback circuit to stabilize first and second voltages across first and second current sources, respectively.