Current-controlled oscillator (CCO) based PLL
US8432204B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 6, 2012 |
| Grant date | Apr 30, 2013 |
| Priority date | — |
| Expiry date | Jan 6, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/099
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A PLL circuit includes a phase frequency detector; a programmable charge pump coupled to an output of the phase frequency detector; a loop filter coupled to an output of the charge pump, the loop filter providing a fine tuning voltage; a first voltage-to-current converter, the first voltage-to-current converter providing a fine tuning current corresponding to the fine tuning voltage; a current-controlled oscillator (CCO); a feedback divider coupled to an output of the CCO and an input of the phase frequency detector; and an analog calibration circuit. The analog calibration circuit provides a coarse adjustment current for coarse adjustments to a frequency pivot point for an oscillator frequency of the CCO, wherein the CCO generates a frequency signal at an output responsive to a summed coarse adjustment and fine tuning current, wherein the frequency pivot point is continuously adjustable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.