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HyperLynx PI does not support this configuration, because it is generally not useful. The decoupling capacitor effect we care about on the PCB is generally between about 10MHz (or higher) to somewhere around 300MHz. The purpose of the ferrite bead is to isolate the high frequency noise between the two plane shapes. Since the ferrite bead blocks the frequencies above about 10MHz, there is generally no need to see how that high-frequency noise propagates through the ferrite.
If you find that your PCB design does not fit into this general case, there is a way to simulate with the ferrite bead. Here is a technote that outlines the method.
Thanks for your reply. The Technote was very helpful.
When running simulations in Decoupling analysis, there seems to be no effect in Z PDN curve, if VRM is assigned or not assigned.
Is VRM taken into consideration for Decoupling analysis?
Because VRM should take care of the low frequency(< 1MHz) before the capacitors take over, Is this included in calculating the Impedance profile?
Please share your views on the same.
The VRM is included in decoupling analysis in version 8.0 through 8.1.1. There was some discussion about removing it in 8.2, but I don't know if that happened. The effect of the VRM is generally at frequencies lower than we care about for decoupling. The overall effect depends on the parameters of the VRM, the transmission planes, the capacitor placement, the capacitor models, and the selection of probe points in distributed decoupling. Try making the resonant frequency of the capacitors higher, and selecting a probe point close to the VRM. Then see if the results are different with and without the VRM model.
Please send Soft copy of HyperLynza PI/SI tech note to this ID