Switching control circuit for discontinuous mode PFC converters
US7116090B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 2005 |
| Grant date | Oct 3, 2006 |
| Priority date | — |
| Expiry date | Oct 19, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A switching control circuit having detection terminal, input terminal, ramp generator, program terminal, error amplifier, mix circuit, and delay circuit for power factor control is provided. The detection terminal generates a detection signal in response to the inductor discharge. An input terminal is connected for detecting a switching current signal. The program terminal determines the slew rate of the ramp signal and the maximum on-time of the switching signal. An error amplifier generates an error signal for regulating the output. A mix circuit generates a mixing signal proportional to ramp signal and the switching current signal. The switching signal is turned on in response to the detection signal, and is turned off based on the error signal. The slew rate of the mixing signal is increased in response to the increase of the input voltage. The on-time of the switching signal is increased inversely proportional to the input voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.