Frequency counter
US4984254A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 7, 1989 |
| Grant date | Jan 8, 1991 |
| Priority date | — |
| Expiry date | Mar 7, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R23/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A frequency counter for counting pulses of a variable input signal (Fin) using another input signal (Fgate) of a different, fixed frequency as a reference, includes a noise-shaping synchronizer (20,23,24) for retiming pulses of the lower frequency input signal to have a fixed timing relationship with selected pulses of the higher frequency input signal such as to introduce substantially less phase noise onto the lower frequency input at low modulation rates that would be the case with a simple synchronizer; and a counter and a latch (11,12) responsive to the retimed pulses (13) and to the higher frequency input signal (Fin) to provide a data output representative of the ratio between the frequencies of the input signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.