Charge pump with low charge injection and low clock feed-through
US7888980B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 2009 |
| Grant date | Feb 15, 2011 |
| Priority date | — |
| Expiry date | Jul 20, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/0896
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A charge pump with low charge injection and low clock feed-through for a phase locked loop (PLL). A first source-switched current mirror has a source transistor and an output transistor. The source transistor has a drain connected to a first current source. The output transistor has a drain connected to an output of the charge pump. The gates of the source and output transistors are coupled together by a first conductive link. A switch is coupled between a supply voltage source and a source of the output transistor of the current mirror. A tuner is coupled between the switch and the output transistor of the current mirror. A source of the tuner is coupled to a drain of the switch and to the source of the output transistor. A drain of the tuner is coupled to the first conductive link between the source and output transistors of the current mirror.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.