High-speed resistor-based charge pump for active loop filter-based phase-locked loops
US9543969B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2015 |
| Grant date | Jan 10, 2017 |
| Priority date | — |
| Expiry date | Dec 7, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/0891
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Techniques are described for increasing the speed of a resistor-based charge pump for an active loop filter-based phase-locked loop (PLL). The techniques may include placing a low-resistance discharge path between respective nodes of a current source and sink in a charge pump, and selectively activating the low-resistance discharge path when the charge pump is turned off. The low-resistance discharge path may have a resistance that is lower than the resistance of other current paths between the respective nodes in the charge pump (e.g., current paths formed by the resistors included in the current source and sink of the charge pump), thereby reducing the amount of time needed to reset the charge on the respective nodes when the charge pump is turned off. In this way, the speed of a resistor-based charge pump may be increased, thereby allowing the overall speed of an active filter-based PLL to be increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.