Circuit and operating method of PLL
US9432030B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 2013 |
| Grant date | Aug 30, 2016 |
| Priority date | — |
| Expiry date | Mar 29, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/0898
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A phase locked loop (PLL) includes a voltage controlled oscillator (VCO), a loop filter, and a feedback control unit. The VCO is configured to generate a first oscillating signal and a second oscillating signal according to a VCO control signal. The loop filter is configured to output the VCO control signal by low-pass filtering a signal at an input node of the loop filter. The feedback control unit has an output node coupled to the input node of the loop filter, the feedback control unit is configured to apply a first predetermined amount of current, along a first current direction, to the first feedback control output node during a variable period of time; and to apply one of K second predetermined amounts of current, along a second current direction opposite the first current direction, to the first feedback control output node during a predetermined period of time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.