Multi-mode charge pump drive circuit with improved input noise at a moment of mode change
US7250810B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 2006 |
| Grant date | Jul 31, 2007 |
| Priority date | — |
| Expiry date | Aug 24, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A multi-mode charge pump drive circuit has a multi-mode charge pump, a switch control circuit, a current regulation circuit, an error amplifier, a variable resistance unit, and a mode selection circuit. The multi-mode charge pump is operated with a plurality of modes, each of which provides a different multiplicative ratio for converting an input voltage source into a drive voltage. The switch control circuit applies a switch control signal to the multi-mode charge pump. The switch control signal has a slew rate of edge for determining a transition span of the interchange between charging and discharging phases. The mode selection circuit controls the multi-mode charge pump to selectively operate with one of the plurality of modes. When the mode selection circuit changes the mode of the multi-mode charge pump, the mode selection circuit applies a mode change signal to the switch control circuit so as to reduce the slew rate of edge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.