Reflective wave compensation on high speed processor cards

Boots – shoes – and leggings

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

379406, 333 4, H04B 1500

Patent

active

056382871

ABSTRACT:
Packaged signal routing circuits (e.g. on printed circuit cards or boards), route pulse signals with very short rise times from a lossy driver to multiple devices. In these routing circuits, a complex network of conductors branches from a common junction adjacent the driver output into multiple (in the disclosed embodiment, three) conduction paths of unequal length. In accordance with the invention, the internal impedance of the driver is matched to the aggregate charateristic impedance of the branch paths, and a lossless compensating circuit is attached to a shortest branch path. The compensating circuit is designed to transfer signal reflections of predetermined form to the branching junction at the driver via the shortest branch. Without the compensating circuit, reflections presented to the branching junction from the shortest branch are dissimilar to reflections presented to that junction from other branch paths. Consequently, re-reflections return from the junction to the branches, causing distortions in signals sensed at the devices. However, with the compensating circuit connected in the shortest branch, reflections presented from that branch to the junction appear in a form matching reflections presented by the other branches; and the reflections from all branches then cancel at the driver junction. Consequently, signals sensed at the devices have considerably reduced distortions due to the absence of re-reflections. In a preferred embodiment, the compensating circuit consists of a printed circuit trace of predetermined length (representing a transmission line stub with predetermined phase delay characteristics) in series with a point capacitor (or several point capacitors) having predetermined capacitance (determining the shape of the compensating reflections). The compensating circuit, which extends beyond the end of the shortest branch, connects between the end of that branch and reference potential (e.g. ground). The end of the shortest branch is also attached to a device required to sense signals appearing at that point. A new method and polarized bridge device are disclosed for use in analyzing such networks in particular (and for analyzing transmission line effects in general). This method and device permit precise observation and comparison of reflections produced in branches of a network emanating from a common junction, and accurate determination of compensation suitable for modifying such reflections.

REFERENCES:
patent: 3370294 (1968-02-01), Kahn
patent: 3419682 (1968-12-01), Thompson et al.
patent: 3462561 (1969-08-01), Deman
patent: 3465106 (1969-09-01), Nagata et al.
patent: 3723883 (1973-03-01), Renner
patent: 4300092 (1981-11-01), Strenglein
patent: 4493092 (1985-01-01), Adams
patent: 4507793 (1985-03-01), Adams
patent: 4645883 (1987-02-01), Horna et al.
patent: 4686703 (1987-08-01), Bruno et al.
patent: 4727543 (1988-02-01), Bauer
patent: 4866768 (1989-09-01), Sinberg
patent: 4998079 (1991-03-01), Theall, Jr.
patent: 5175515 (1992-12-01), Abernthy et al.
patent: 5304856 (1994-04-01), Rainal

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

Reflective wave compensation on high speed processor cards does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Reflective wave compensation on high speed processor cards, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reflective wave compensation on high speed processor cards will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-770154

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