Digitally controlled oscillator (DCO) for a phase locked loop (PLL) system
US9559709B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2015 |
| Grant date | Jan 31, 2017 |
| Priority date | — |
| Expiry date | Sep 28, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2005/00019
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A digital controlled oscillator (DCO) is provided that includes a plurality of selectable delay cells, a first load adjustment delay (LAD) cell, a second LAD cell, a first set of the load cells (LCs), a second set of the LCs and first and second capacitance elements. A number of the selectable delay cells that are part of a delay cell chain is configurable based on a delay cell number control vector. The delay cell chain generates a delay cell output signal that is received by the first LAD cell. The first set of the LCs generate a first load signal to control an amount of loading on the second LAD cell, and the second set of the LCs generate a second load signal to control loading on the first LAD cell. Substrate voltages of the first and second capacitance elements can be adjusted to adjust loading in the DCO.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.