Phase comparator
US5789947A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 19, 1996 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | Sep 19, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/089
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A phase comparator has a first comparing circuit and a second comparing circuit. The first comparing circuit produces a first output pulse having a duration equal to a phase lead of a first input signal with respect to a phase of a second input signal. The first phase comparator also produces a second output pulse equal in duration to a phase lag of the first input signal with respect to the phase of the second input signal. The second comparing circuit produces a third pulse equal in duration to a phase lead of a third input signal with respect to a phase of a fourth input signal. The second comparator also produces a fourth output pulse equal in duration to a phase lag of the third input signal with respect to the phase of the fourth input signal. The phase comparator further includes a first combining circuit for combining the first output pulse with the third output pulse, a second combining circuit for combining the second output pulse with the fourth output pulse, and a first delay circuit for relatively delaying the first input signal with respect to the third input signal. Optionally, a second delay circuit delays the fourth input signal relative to the second input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.