Circuits and methods for detecting phase lock

Details Circuits and methods for detecting phase lock Circuits and methods for detecting phase lock

2007-02-27

2007-02-27

Mis, David (Department: 2817)

Oscillators

Automatic frequency stabilization using a phase or frequency...

Afc with logic elements

C331SDIG002

Reexamination Certificate

active

11179365

ABSTRACT:
In a phase-locked loop circuit including a lock detection function, the phase-locked loop circuit includes a lock detection circuit. The lock detection circuit includes a lock-window-entry detection circuit and a lock-detection-signal generation circuit. The lock-window-entry detection circuit detects a front edge of an up signal or a down signal generated by a phase frequency detector at a front edge of a delayed up signal or a delayed down signal to generate a lock-window-entry detection signal, wherein the delayed up signal or the delayed down signal is delayed substantially by as much as a lock window. The lock-detection-signal generation circuit counts an input signal of a phase-locked loop circuit to generate a lock detection signal when the lock-window-entry detection signal is continuously enabled for a predetermined time period. In this manner, a lock detection signal is output only when the phase locking operation has been completed.

REFERENCES:
patent: 4668917 (1987-05-01), Levine
patent: 6496554 (2002-12-01), Ahn
patent: 2002/0094054 (2002-07-01), Lee
patent: 2005/0073343 (2005-04-01), Kim et al.
patent: 09-036735 (1997-02-01), None
patent: 2002-344312 (2002-11-01), None
patent: 1992-0014072 (1992-07-01), None
patent: 1995-0002376 (1995-01-01), None
patent: 1999-0080623 (1999-11-01), None
patent: 1020020022918 (2002-03-01), None
patent: 1020020042161 (2002-06-01), None
patent: 10-2005-0033896 (2005-04-01), None

Affiliated with

Also associated with

Rating

Circuits and methods for detecting phase lock does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Circuits and methods for detecting phase lock, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuits and methods for detecting phase lock will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3854452