Power controllers and control methods suitable for operating a switched mode power supply in quasi-resonant mode
US8964417B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2013 |
| Grant date | Feb 24, 2015 |
| Priority date | — |
| Expiry date | Dec 2, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The disclosure provides a power controller and related control method for a switch mode power supply operating in a quasi-resonant mode. The switched mode power supply has a power switch and an auxiliary winding. The power controller has a feedback pin connected to the auxiliary winding. A clamp circuit is connected to the feedback pin and configured for clamping a voltage at the feedback pin by providing a clamp current. A peak hold circuit is connected to the clamp circuit for generating a peak record substantially corresponding to a peak value of the clamp current. A valley detector is configured for providing an entry signal indicating a start of a voltage valley. A delay circuit provides a trigger signal a delay time after the entry signal is provided. The delay time varies in response to the peak record, and the trigger signal is capable of turning on the power switch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.