Switching power supply
US7385380B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 10, 2007 |
| Grant date | Jun 10, 2008 |
| Priority date | — |
| Expiry date | Jan 10, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/0027
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a switching power supply apparatus for performing a switching control of a power MOS transistor that flows current to a coil and converting input voltage into output voltage, even if there occurs offset voltage in a current sensing operational amplifier, source potential of a current sensing MOS transistor is precisely kept at source potential of a low side power MOS transistor. For example, an offset cancel capacitor is arranged at an inverting input terminal of the current sensing operational amplifier, and voltage in the direction to offset the offset voltage occurring in the operational amplifier is charged to this capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.