Patent ID: 8693217

Claim:
A power supply controller, comprising: a signal separator circuit coupled to generate a feedback signal in response to a sense signal representative of an output of a power supply; an error signal generator coupled to generate an error signal in response to the feedback signal and a reference signal; and a control circuit coupled to generate a drive signal in response to the error signal and a current sense signal, wherein the drive signal is coupled to control switching of a switch of the power supply, wherein the current sense signal is representative of a current through the switch; and a multi-cycle modulation circuit included in the control circuit and coupled to generate a first signal in response to a second signal, a third signal and a fourth signal, wherein the first signal is coupled to inhibit the drive signal, wherein the fourth signal is generated in response to the first signal, wherein the second signal is coupled to cause the drive signal to start skipping on-time intervals of cycles, wherein the third signal is coupled to cause the drive signal to stop skipping the on-time intervals of cycles, wherein the fourth signal is coupled to disable the second signal from causing the drive signal to start skipping the on-time intervals of cycles, and wherein a sum of the on-time intervals of cycles and the skipped on-time intervals of cycles is greater than or equal to a constant, wherein the multi-cycle modulation circuit includes a filter circuit including a counter coupled to a first logical AND gate, wherein the counter has a plurality of binary outputs that are coupled to be received by the first logical AND gate, wherein the first logical AND gate is coupled to reset the fourth signal in response to the plurality of binary outputs received from the counter.