Frequency calibration for a monolithic clock generator and timing/frequency reference
US7548125B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 2007 |
| Grant date | Jun 16, 2009 |
| Priority date | — |
| Expiry date | Aug 10, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R23/15
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Exemplary embodiments of the invention provide a system, method and apparatus for frequency calibration of a free-running, reference harmonic oscillator. An exemplary system comprises the harmonic oscillator, a frequency divider, a comparator, and a reactance modulator. The reference harmonic oscillator includes a plurality of switchable reactance modules controlled by corresponding coefficients, and provides an oscillation signal having an oscillation frequency, which is divided or multiplied by the frequency divider to provide an output signal having an output frequency. The comparator compares the output frequency to an externally supplied reference frequency using first and second predetermined levels of discrimination, and provides first or second comparison signals when the output frequency is higher or lower than the reference frequency. The reactance modulator determines a plurality of coefficients to control switching of the plurality of switchable reactance modules to increase or decrease a reactance of the oscillator in response to the first and second comparison signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.