Re: [SI-LIST] : stackup impedance.

[email protected]
Wed, 17 Sep 1997 11:10:48 -0400

Hi John,

In the first case, the G-P stackup essentially shields
the S-S layers on either side, so you could break this
stackup into S-S-G and P-S-S and analyse it as a microstrip

Second case is quite different from the first one.
You have to analyse it as a stripline configuration


I think the performance of the S-S-G-P-S-S stackup
would be better than the other one.

Hope it helps, best wishes


John Lin - TAO wrote:
> Hi,
> Does anybody have idea about how to calculate the impedance of
> stackup with following structures.
> S-S-G-P-S-S ( 6 layers).
> and
> G-S-S-S-S-P (6 layers).
> I checked books and tried to find equations to calculate impedance.
> However, I cannot find any.
> Best Regards,
> CAE Engineer of EDA Department
> Digital Equipment Corp. Taiwan Branch
> Email: [email protected]
> TEL: 1-886-3-3900000 ext. 2565

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