RE: [SI-LIST] : skin effect and transmission line simulators

Mellitz, Richard (mellitz@xgate.columbiasc.ncr.com)
Tue, 9 Sep 1997 07:40:53 -0400

Interesting. BGA foot print effects... eh. So how big a problem is
it? Are we talking greater than or less than 100 ps of extra transition
time delay? Are coupling coefficients increased by greater that 10%? I
know.. I know.. What frequency, what drive, etc. etc.. Do you have a
handle on how big a problem it is and when it is prudent to include
such?

Rich Mellitz, NCR
>----------
>From: Dr. Edward P. Sayre[SMTP:esayre@nesa.com]
>Sent: Monday, September 08, 1997 7:27 PM
>To: fangj@binghamton.edu
>Cc: si-list@silab.Eng.Sun.COM
>Subject: Re: [SI-LIST] : skin effect and transmission line simulators
>
>Funny you should mention this. This is exactly the problem in estimating
>the footprint effects we have seen in BGA dispersion problems. Having the
>package paramters is only half the problem. Who will provide the rest of
>the circuit information for packaging?
>
>ed sayre
>
>At 11:20 AM 9/5/97 -0400, you wrote:
>>
>>
>>On Thu, 4 Sep 1997, Al Barber wrote:
>>
>>> Chris Simon wrote:
>>> >
>>>
>>> > The simulator I'm looking for should include all of the following:
>>> ....
>>> >
>>> > I would be interested in hearing which of the above criteria are met by
>>> > other tools, or whether a future revision will incorporate these
>>>>features.
>>>
>>> There is an additional feature I'm surprised you don't mention. How
>>> about crosstalk among multiple lines?
>>>
>>> Al Barber
>>> Hewlett Packard Labs
>>>
>>
>>Crosstalk not only appears between multiple parallel lines, but also
>>between vias. Our recent study shows that electromagnetic coupling between
>>vias is often as significant as or sometimes even more significant than
>>the coupling between parallel traces. A signal integrity software tool is
>>better to be able to accurately model the coupling between multiple lines,
>>vias, as well as the voltage fluctuations in the power and ground supply
>>systems.
>>
>>
>>Jiayuan Fang
>>SUNY-Binghamton
>>
>>
>>
>
>
>
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