.SIGMA.-.DELTA. modulator-controlled phase-locked-loop circuit
US5986512A · kind A · utility
52Cited by
5References
31Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 12, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Dec 12, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M7/304
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A .SIGMA..DELTA. modulator-controlled, phase-locked-loop circuit, and an associated method, generates a frequency-regulated signal which does not exhibit undesired tones. Dithering signals are generated and are provided to a .SIGMA..DELTA. modulator. The .SIGMA..DELTA. modulator forms a division-factor control signal used to control the division factor of a frequency divider forming a portion of the PLL circuit. The dithering signals applied to the .SIGMA..DELTA. modulator reduce the likelihood that the .SIGMA..DELTA. modulator shall enter a limit cycle and generate repetitive output signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.