Phase-locked loop which can automatically adjust to and lock upo

Details Phase-locked loop which can automatically adjust to and lock upo Phase-locked loop which can automatically adjust to and lock upo

1997-10-16

2000-04-11

Kinkead, Arnold

Oscillators

Automatic frequency stabilization using a phase or frequency...

Tuning compensation

331 25, 331 1A, 331 17, 327156, 327159, 327160, H03L 718

Patent

active

060492546

ABSTRACT:
An apparatus is provided for automatically and dynamically adjusting a frequency division factor of a clock divider situated in the feedback loop of a phase-locked loop (PLL). The frequency division factor is modified based on changes in the input signal frequency forwarded to the PLL. If the input signal frequency increases, the decision circuit coupled to the input of the voltage controlled oscillator records that change as an encoded digital signal. That signal will accordingly modify the current frequency division factor dependent on current division factor as well as the current input signal frequency. The decision circuit can be modeled as an A/D converter, and the control unit placed between the decision circuit and the clock divider can be modeled as a state diagram. Each state of the state diagram is indicative of a frequency division factor, or a change in that division factor, wherein the coded digital signal indicates possible change from one state to another. By modifying the frequency division factor, the PLL can dynamically lock upon a changed input signal frequency without varying the clocking signal output from the PLL. Thus, the PLL can accommodate various input signal frequencies yet maintain a relatively fixed clocking signal to be forwarded as a timing reference to a digital processor.

REFERENCES:
patent: 4516083 (1985-05-01), Turney
patent: 5281926 (1994-01-01), Rabii
patent: 5334952 (1994-08-01), Maddy et al.
patent: 5371480 (1994-12-01), Hedberg et al.
English Abstract for Patent Abstract of Japan; Publication No. 53054456; Publication Date May 17, 1978; Application Date Oct. 27, 1976; Application No. 51129919; Applicant Mitsubishi Electric Corp.
International Search Report for PCT/US 98/21889 mailed on Feb. 24, 1999.

Affiliated with

Also associated with

Rating

Phase-locked loop which can automatically adjust to and lock upo does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Phase-locked loop which can automatically adjust to and lock upo, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase-locked loop which can automatically adjust to and lock upo will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1179812