Patent ID: 11942856
Assignee: ARK MICROELECTRONIC CORP. LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 9:
10. A method of operating a power conversion apparatus, the power conversion apparatus configured to supply power to a load, the method comprising steps of:
alternately turning on and turning off a power switch of the power conversion apparatus to convert an input voltage into an output voltage through a transformer,
sensing an auxiliary voltage through the transformer to provide a level signal corresponding to a voltage level of the output voltage according to the auxiliary voltage,
setting a predetermined counting threshold according to the level signal, and setting a blanking time interval according to a feedback signal, wherein the feedback signal is related to the load,
counting a number of oscillation turning points presented during an oscillation of a resonance voltage after the blanking time interval ends, and
turning on the power switch when the number reaches the predetermined counting threshold.