CMOS circuit providing 90 degree phase delay

Oscillators – Automatic frequency stabilization using a phase or frequency... – Particular error voltage control

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

331 1A, 331 18, 331 25, 331 57, 341 68, 360 41, 360 51, 375120, H03L 700

Patent

active

053999959

ABSTRACT:
A high speed clock recovery system that provides a precise 90.degree. phase shift at the incoming NRZ data rate by using a series of differential inverters and controlling their delays in accordance with the corresponding delays of differential inverters of a ring oscillator that is part of a phase-locked loop. More particularly, the incoming NRZ data and the phase shifted data are fed to an exclusive OR that provides an output signal including a frequency component of the originating clock of the NRZ data. The phase-locked loop further includes a phase detector which is responsive to the output of the exclusive OR and the ring oscillator. Thus, once the loop locks, the ring oscillator is synchronized to the frequency of the originating clock for the NRZ data. By slaving the differential inverters of the phase shifter and the ring oscillator to the same delays, the phase shifter provides a dynamically adjusted delay of precisely 90.degree. at the originating clock frequency of the incoming NRZ data.

REFERENCES:
patent: 4868522 (1989-09-01), Popat et al.
patent: 5043677 (1991-08-01), Tomassetti et al.
patent: 5163067 (1992-11-01), Wight et al.
patent: 5164966 (1992-11-01), Hershberger
patent: 5172397 (1992-12-01), Llewellyn
patent: 5180994 (1993-01-01), Martin et al.
patent: 5191301 (1993-03-01), Mullgrav, Jr.
patent: 5239274 (1993-08-01), Chi
patent: 5250913 (1993-10-01), Gleichert et al.
patent: 5258877 (1993-11-01), Leake et al.
patent: 5260841 (1993-11-01), Suzuki et al.
patent: 5307028 (1994-04-01), Chen
patent: 5343167 (1994-08-01), Masumoto et al.
"A 30-MHz Hybrid Analog/Digital Clock Recovery Circuit in 2-.mu.m CMOS," B. Kim, D. N. Helman, P. R. Gray, IEEE Journal of Solid State Circuits, vol. 25, No. 6 pp. 1385-1394, Dec. 1990.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

CMOS circuit providing 90 degree phase delay does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with CMOS circuit providing 90 degree phase delay, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and CMOS circuit providing 90 degree phase delay will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1151863

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.