Switched mode power supply device adapted for low current drains, and cellular phone equipped with such a device
US6897640B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2002 |
| Grant date | May 24, 2005 |
| Priority date | — |
| Expiry date | Sep 6, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/156
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A switched mode power supply device comprising a power transistor periodically set to conduction and supplying a regulated voltage that comprises a ramp generation circuit controlled by a clock signal and periodically generating a ramp voltage. The device includes an amplifier error circuit between a reference voltage and said regulated output voltage and generates an error signal, and a comparator comparing the ramp voltage with said error voltage and providing an output signal for controlling said power circuit. The circuit is characterized in that it comprises a delay element delaying the setting to conduction of the power transistor so as to desynchronize the starting of the ramp and said setting to conduction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.