siwave simulation results

[buenos]

hi.

if i do a power-plane simlation with siwave, then the results look strange.

-in resonant mode analysis, the result amplitude is always between +/-1V. independently of any changes on the PCB. is it a normalised result? for example if there is a 1.8V plane, then what will be the maximum amplitude (at a given resonant mode, at the peak location on the PCB.)

-I want to know the AC impedance of the plane on a given point on the PCB. i specified a port (as an IC power input pin), so the "compute S, Y, Z param" results should show it, right? on the Z parameteer graph, it seems, the impedance is zero at zero frequency. as i know, it should be infinit. which graph shows the impedance versus frequency? the s-parameter plot: is it S12? S11?...

-in the nets view, there is only one net shown. i followed an siwave userguide, but there is nothing about specifying nets.

 

[sigint]

S11 and S12 for a power plane????? a power plane only exhibits resistive impedance and inductance.

SiGiNT

 

[buenos]

i would use s-parameters for interconnect simulation. "the s-parameter plot: is it S12? S11?... "