How to determine per length RLC in a board

Hi, All:

If the stackup in a board is a symmetric stripline structure (GND-SIG-PWR),
the characteristic impedance is the same for switching high and low, and the
per length RLC are also the same for both switching cases.

How to determine the per length RLC in a board with a stackup like
SIG-GND-PWR? The characteristic impedance and per length RLC are
switching-dependent, but there is no way to put two values for each trace in
an ebd file.

Intel uses ebd to describe packages used for Pentium processors,I have the
same question there on the way to determine RLC values.

Your help is appreciated.

Thanks,

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Yaping Zhou (r3aadv)
(512) 933-5803
Motorola Semiconductor Products Sector
Final Manufacturing Technology Center
Ed Bluestein, Austin, Texas
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