GND Plane Bounce Question

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     All IBISians (SI experts by Default !!)
     
     I would like to pose the following SI question, and solicit help from
     those who actually know the answer or have a very good idea of how to
     estimate it by scaling from previous experience:
     
     
     Assume one GND and one power plane in a PCB separated by say 10 mil,
     with a dielectric constant of say 4. assume that the power plane has a
     via opening where current is injected thru the via down to the GND
     plane. Let's say that the current is 10 Amps. with a riserime of 1 ns.
     Assume nominal via diameter. The drawing below shows the structure:
     
                      
                      | Vcc
     ---------------- | ------------------
                      | GND 10 mil, Er=4
     -----------------|-------------------
     
     
     What I would like to hear from anybody who actually has experienced
     GND plane bounce, is:
     
     *howmuch do you expect the GND plane (not the via stem) to bounce up
     (locally) given the above assumptions, and
     
     *howfar away from the via (radially) do you expect the bounce to drop
     to 10% of the peak which occurs right where the via meets the plane ?
     
     I would apprciate a good guess (and Why: perhaps from previous
     experience), or direction as to "who ?" you think could answer such a
     question. I know that I might need to do a 3-D or radial transmission
     line analysis of the system, but I'm really just looking for a quick
     answer.
     
     
     Thanks for taking the time to read or answer this question.
     
     Samie Samaan
     Intel Corp.
Received on Mon Aug 21 11:32:19 1995