Boost circuit capable of step-up ratio control
US7304871B2 · kind B2 · utility
23Cited by
1References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2005 |
| Grant date | Dec 4, 2007 |
| Priority date | — |
| Expiry date | Dec 6, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
When a step-up ratio control circuit sets a step-up ratio of a charge pump circuit to 1.0 to enable a short mode, a path inside the charge pump circuit is short-circuited and a first transistor is completely turned on. This produces an inrush current derived from a battery voltage of a lithium ion battery flowing into the charge pump circuit. To address this, a constant current circuit is operated so that the first transistor is turned on slowly. Further, the operation of an oscillator and an operational amplifier is suspended when the short mode is enabled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.