[SI-LIST] Re: doubt about crosstalk.
- From: MikonCons@xxxxxxx
- To: si-list@xxxxxxxxxxxxx
- Date: Wed, 24 Jul 2002 17:56:31 EDT
Per multiple comments/requests:
[Q] "I was wondering if you did a control with the same layout without the
guard trace
and only used the spacing as the isolation?"
[Mikon] Yes. The reference point for performance was precisely what you
describe. As I originally stated, "A series of microstrips, guarded
microstrips, striplines, and guarded striplines were constructed at specified
50 Ohm trace levels. The center-to-center spacing of the signal traces was
maintained for all configurations and the trace widths adjusted to achieve
the targeted 50 Ohm level for all lines."
[Q] "There are two components to crosstalk, magnetic and capacitive. I can
see
where a guard trace can easily help with the capacitive crosstalk but the
effects on magnetic crosstalk would be much less. The magnetic field contains
energy in the flux lines. It is unclear to me whether the magnetic crosstalk
can
be lowered by placing a parasitic loop between the aggressor and the victim
traces.
[Mikon] The guard traces (as well as the ground planes) carry high frequency
return currents (i.e., in the opposite direction) induced by the signals and
help reduce the magnetic loop and the field intensities created thereby.
[Q] "Can you please share your study with this group."
Actually, I thought I just did share my results, at least about the crosstalk
question. In the same tutorial, I also introduced the multiple-layer,
co-planar, via-connected, chassis ground trace techniques for reduction of
edge-related radiated emissions (and superior ESD protection), multiple other
radiation and crosstalk reduction techniques, and a dissertation on buried
capacitance versus discrete capacitors for power distribution system
decoupling. The full tutorial is over an hour long and has long since been
archived in my files. It was also in a different presentation format than the
now more common Microsoft PowerPoint files.
You might try to access the files at Hewlett-Packard (now Agilent) as that
work is published multiple times in the 1990 to 1993 HP High-Speed Design
Seminar books. They also did a videotape of my associated presentation which
was marketed (via a third party) out of either San Antonio or Houston, Texas
(I don't precisely recall which).
The most recent publication I know of is in both the U.S. and European HP
seminar books "1993 High Speed Digital Design Symposium." At that time, Jim
Kabel was the Test and Measurement U.S. Marketing Center Manager for HP. You
might try to locate more information through him.
That's all I have time for now, so good luck.
Mike
Michael L. Conn
Owner/Principal Consultant
Mikon Consulting
*** Serving Your Needs with Technical Excellence ***
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
