Switching power supply for reducing external parts for overcurrent protection
US7535736B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 2007 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | Nov 9, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/32
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A switching power supply has a switching device connected via a primary winding of a transformer to DC input voltage; a circuit for rectifying voltage at a secondary winding of the transformer, and outputting an output signal; and a control circuit for controlling on/off states of the switching device. The control circuit detects a current signal generated based on a forward voltage generated at a drive winding of the transformer while the switching device is on; generates an input correction signal using the current signal, the level of the input correction signal varying in accordance with the DC input voltage; detects a signal of current flowing through the switching device; and compares the input correction signal with the signal of the current flowing through the switching device, and limits the maximum value of this current in accordance with the DC input voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.