Differential charge pump with common-mode feedback compensation
US7075348B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 2002 |
| Grant date | Jul 11, 2006 |
| Priority date | — |
| Expiry date | Oct 16, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/0896
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A differential charge pump includes a first current, a second current, a first switching device, a second switching device, a first phase inverting switching device, a second phase inverting switching device, and a common mode feedback device. The common mode feedback device is used to adjust the current level exported by the first current source, according to the common mode voltage of the differential charge pump, so that the respective currents exported by the first current source and the second current source are to be the same. The present invention has used the property that the common mode voltage of the differential charge pump should be a constant value, so as to correct the level of the current source. As a result, the current exported by the differential charge pump can be precisely corrected. Also, the present invention only needs one charge pump, so that the structure is simple and the fabrication is easy. In addition, no matter whether there is a rising or falling signal, the correction can be performed. Therefore, it has no issue of shift for the common mode voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.