Frequency synthesizing device and automatic calibration method thereof
US10218367B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 2017 |
| Grant date | Feb 26, 2019 |
| Priority date | — |
| Expiry date | May 5, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L2207/06
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A frequency synthesizing device includes a voltage-controlled oscillator receiving an adjusting signal and generating an output signal according to the adjusting signal. A feedback frequency divider having a plurality of divisor values receives the output signal and generates a feedback signal after performing frequency dividing. An automatic frequency calibration circuit of the frequency synthesizing device includes a first frequency divider receiving a reference frequency, and a second frequency divider receiving the feedback signal. A comparator of the automatic frequency calibration circuit receives and compares outputs from the first frequency divider and the second frequency divider in a predetermined period to generate a comparing result. A state machine outputs the adjusting signal according to the comparing result in a calibration mode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.