-----Original
Message-----
From: Mellitz, Richard
[mailto:richard.mellitz@INTEL.COM]
Sent: Wednesday,
January 18, 2006
4:09 PM
To:
STDS-802-3-BLADE@listserv.ieee.org
Subject: Re: [BP]
Interference
tolerance test channels
Did
it!
I built a channel that has 3db less loss at 5GHz with out impacting
the
loss at 1GHz. Also I created the AF coefficients to match this channel.
See
attached zip file. I also checked the causality of the s4p as well. J
…Rich
Steve,
But also
realize that the general line
also has built in margin for it to account for temperature,
environmental, and
material variation as well. The line as currently proposed has to
be examined to look at from several aspects. For example, the Molex
channels are hugging the new proposed 23 dB line. 5” are on the
daughtercard and 35” are on the backplane, which uses a typical 7 mil
line. So we are saying that to meet the skin effect at the lower
frequencies we need a 7 mil wide line? I think that is too far.
Look at the attached figure – 7 mil wide traces hug that line. I
think we have moved it too far upward.
I don’t see
any efforts yet on
reducing the problem via the crosstalk aspect of the problem. Has that
been abandoned? I don’t think all of the burden at this time should
be shifted to the channel, but should also be shared with the total
allowable
crosstalk. Many of the channels did have margin. We should look to
striking a balance between the two.
John
-----Original
Message-----
From: Steve Anderson
[mailto:steve.anderson@xilinx.com]
Sent: Monday,
January 16, 2006
2:52 PM
To: DAmbrosia, John
F;
STDS-802-3-BLADE@listserv.ieee.org
Subject: RE: [BP]
Interference
tolerance test channels
John, all:
But does a line made with the squared and cubed terms create a
physically
realizable channel?
In the real channel I think there may be only two variables to play
with:
skin effect and dielectric
absorption.
If we
base simulations on something other than this, then I think bad things
can
happen like
non-causal
effects.
Steve A.
Guys,
Goergen
asked the magic
question. Is it possible? Yes it is. We have a squared and
cubed term to play with. I am hoping Joel has some suggestions as
well. I just had a chance to do a quick scan and saw this. I will
be working on this stuff tonight
John
-----Original
Message-----
From: Oganessyan,
Gourgen
[mailto:Gourgen.Oganessyan@MOLEX.COM]
Sent: Monday,
January 16, 2006
2:24 PM
To:
STDS-802-3-BLADE@listserv.ieee.org
Subject: Re: [BP]
Interference
tolerance test channels
I see
now what you refer too. I am not sure how you physically relaize a
channel you
are suggesting, keep low freq the same and come up at 5 GHz? Any
physical
channel should result in a tilted line?
-----Original
Message-----
From: Mellitz, Richard
[mailto:richard.mellitz@INTEL.COM]
Sent: Monday,
January 16, 2006
1:05 PM
To:
STDS-802-3-BLADE@listserv.ieee.org
Subject: Re: [BP]
Interference
tolerance test channels
The
line didn’t only tilt. It also shifted. John D looked
at a few channels as I attached. If we shift, it’s got an impact for KX
and KX4.
…Rich
The new channel appears
to be inline with what we stated - a tilt of the
line from DC to about a 3dB drop at 5GHz. Why do you feel the lower
frequencies need to stay fixed?
Thanks, Joe
Joe Abler
abler@us.ibm.com
IBM Systems & Technology Group
919-254-0573
High Speed Serial Link Solutions
919-254-9616 (fax)
3039 Cornwallis Road
Research Triangle Park, NC 27709
Hi Charles,
DC and low freq's went down way to much! Can you create a model with the
same losses at say 1GHz or so and 2 dB less at 5GHz? I thought that's
what we agreed.
... Rich
-----Original Message-----
From: Charles Moore [mailto:charles.moore@avagotech.com]
Sent: Friday, January 13, 2006 8:42 PM
To: STDS-802-3-BLADE@listserv.ieee.org
Subject: [BP] Interference tolerance test channels
guys,
I propose that we use the model ITTC_23.s4p for reduced
attenuation
EIT modeling. If it really will not work, ITTC_20.s4p is available as a
bail out channel. If it looks too easy, let me know and i will step it
up just
a tad.
The numbers refer to the fitted attenuation at 5.15...GHz.
charles
--
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| Charles Moore
| Avago Technologies
| Image Solutions Division
| charles.moore@avagotech.com
| (970) 288-4561
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