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High Memory Requirement for PCB Simulation

Question asked by bijanbina001 on Dec 30, 2018
Latest reply on Jan 11, 2019 by bafisher

I'm exporting a PCB design from the Cadence Allegro to ADS 2017.1. The design is a 10 layer board with RF and digital section. I removed the digital fraction so only RF components are remained. Moreover I only export traces and port (created on smd pads of each component) so the design now have almost 70 ports (most of them are decoupling capacitors and others are switches, LNAs and baluns which are making a 4x4 transceiver) and exported without any components (IBIS, ESPICE, ...)


Then in ADS layout I created a model by EM  > Component > Create EM Model and Symbol from my PCB and add appropriate components between each ports (cap, switch, ...). Finally I add S-Param simulation into the schematic and  configured EM Setup to "EM Simulation Model" and use "Momentum RF" as simulator.


1. But running the simulation will occupy 30GB of memory (After 30minutes) and because of low memory eventually the simulation terminates due to lack of free memory space. I can increase virtual memory (I'm using Win7) but is it normal for  a Momentum to use this much of memory?

PCB Detail:

Max Frequency: 6GHz

Dimension of RF cutout: 10cm x 4cm

IC Component: 12

Passive Component: 20


2. After that I closed my schematic cell and tried to use FEM simulator in layout window (Because of available option for memory limitation) but after 10 minutes, simulation aborted with following error:

Traceback (most recent call last):
  File "G:\Software\Program Files\Keysight\ADS2017_Update1\Momentum\12.62\fem_scripts\", line 1155, in import_settings_and_simulate
    simresult = self.simulate(proj.maxNbThreadsADS(), permEMPro2Ads)
  File "G:\Software\Program Files\Keysight\ADS2017_Update1\Momentum\12.62\fem_scripts\", line 542, in simulate
    lastsim = empro.activeProject.createSimulation(False)
  File "G:\Software\Program Files\Keysight\ADS2017_Update1\fem\2017.10/Win32_64/bin\empro\", line 58, in createSimulation
    return self._createSimulation(iQueue)
RuntimeError: Unable to create a new FEM simulation because the project must be valid before creating a simulation.  The invalidity message is: An enabled Circuit Component is invalid


I don't see any component in "Navigator" pane. Is there any way to check why this error is happening?