Offline synchronous rectifying circuit with current transformer for soft switching power converters
US8004862B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2008 |
| Grant date | Aug 23, 2011 |
| Priority date | — |
| Expiry date | Apr 23, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A synchronous rectifying circuit of soft switching power converter is provided to improve the efficiency. The integrated synchronous rectifier includes a power transistor connected from a transformer to the output of the power converter for rectifying. A controller having a latch circuit generates a drive signal to control the power transistor in response to a switching-current signal. A current transformer generates the switching-current signal in response to the switching current of the transformer. The controller turns off the power transistor when the switching-current signal is lower than a second threshold. The power transistor is turned on once the switching-current signal is higher than a first threshold. Furthermore, a pulse-width detection circuit generates a pulse signal coupled to disable the drive signal and turn off the power transistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.