Patent ID: 8385088

Claim:
A control circuit for use in a power converter, comprising: a drive signal generator coupled to generate a drive signal to control switching of a power switch to be coupled to the control circuit to regulate a flow of energy to a power converter output in response to an energy requirement of one or more loads to be coupled to the power converter output; an unregulated dormant mode and output reset control circuit coupled to render dormant the drive signal generator thereby ceasing the regulation of the flow of energy to the power converter output by the drive signal generator when the energy requirement of the one or more loads falls below a threshold, the drive signal generator coupled to be unresponsive to changes in the energy requirements of the one or more loads when dormant, the unregulated dormant mode control circuit coupled to power up the drive signal generator after a first time period has elapsed, the drive signal generator coupled to again be responsive to changes in the energy requirement of the one or more loads after the first time period has elapsed; a load detection circuit included in the unregulated dormant mode and output reset control circuit, the load detection circuit coupled to identify, after the first time period has elapsed, an increase in the energy requirement of the one or more loads by counting a threshold number of cycles for which substantially high power is delivered by the power converter to the one or more loads; and an output reset circuit included in the unregulated dormant mode and output reset control circuit, the output reset circuit coupled to the load detection circuit and the drive signal generator, the output reset circuit coupled to cease in response to the load detection circuit the flow of energy to the one or more loads during a second time period after the first time period has elapsed to allow a voltage at the power converter output to be discharged to a value substantially below a normal regulation output voltage.