Switching controller for flyback power converters without input capacitor
US9007786B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 2012 |
| Grant date | Apr 14, 2015 |
| Priority date | — |
| Expiry date | Feb 10, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/0022
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention proposes a switching controller of a flyback power converter. The switching controller includes a switching circuit, a sample-and-hold circuit, a voltage detection circuit, an oscillation circuit, and a comparator. The voltage detection circuit generates a holding signal when a level of an input voltage of the flyback power converter is lower than a low-threshold. The oscillation circuit limits the maximum frequency of switching signal. The maximum frequency is increased in response to a decrement of a modulation signal. The modulation signal correlated with a level of the input voltage is used to generate a control signal when the level of the input voltage is lower than an ultra-low-threshold. The control signal is enabled to operate the flyback power converter in continuous current mode operation. Therefore, an input capacitor can be eliminated and manufacturing cost is saved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.