Clock generator and method for reducing electromagnetic interference from digital systems
US9900145B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 2016 |
| Grant date | Feb 20, 2018 |
| Priority date | — |
| Expiry date | May 19, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/84
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A spread-spectrum clock generator has a phase-locked loop locked to a reference signal that gives a stable-frequency output to a variable phase shifter. The variable phase shifter provides a spread-spectrum clock output because its phase-shift is determined by a pseudorandom sequence generator and the pseudorandom sequence generator changes its output regularly or irregularly within limits. The clock generator performs a method of generating a spread-spectrum clock including locking the phase-locked loop to the reference signal, and phase shifting the stable frequency signal by a phase-shift determined by the pseudorandom sequence generator; and changing the phase-shift determined by the pseudorandom sequence generator. Since phase shifting is performed open-loop, total phase shift is defined by design.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.