Phase/frequency comparator
US5438285A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 17, 1993 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Mar 17, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D13/004
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A phase/frequency comparator includes: two inputs which respectively receive first and second logic signals; a first logic gate which is at an active state during a duration equal to the phase advance of the first signal with respect to the second signal; and a second logic gate which is at an active state during a duration equal to the phase advance of said second signal with respect to the first signal. The phase/frequency comparator also includes: a first switching element operated by the active state of the second gate to prevent transmission to the first gate a state liable to switch the first gate to its active state; and a second switching element operated by the active state of the first gate to prevent transmission to the second gate a state liable to switch the second gate to its active state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.