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Hiding child instances

shridmaster

I'm trying to do what I believe should be a very simple and straightforward thing but after much reading appears to be quite complicated.

I'm test-benching the digital portion of a mixed-signal circuit that's instantiated a few hundred times. Each instance has some digital controls, and an analog portion. To greatly speed up the simulation, I'd like to hide the analog portion, which is neatly contained in one or two cell views deep down the hierarchy, and then unhide it after simulation has ended so it doesn't mess up other peoples' sims

Just as an example, say there's an op-amp that from the top level is contained in instance "I<0:511>/I3/I15/I0". First off, I don't know how to iterate through the 512 instantiations of the top level cell, but let's say we're just working with the I0 instance. I thought it would just be

schIgnore(?objectId "I<0:511>/I3/I15/I0" ?setIgnore t)

Of course this doesn't work. I can get the top level cell dbId with

cv = dbOpenCellViewByType("library" "cell" "schematic" "" "a")

And then I can grab the instance ID with

inst = dbFindAnyInstByName(cv "I0")

This gives me something, but then I'm lost from here. If I use the ~>master to get an Id from inst, I cannot recursively use dbFindAnyInstByName to traverse down the hierarchy. Also the value this returned seems to be meaningless, it can't be used by the schIgnore command. I'm not sure what the schIgnore command is actually even looking for.

So I guess I'm trying to loop through two things, one is to traverse down the hierarchy and grab the ID of a child instance so I can schIgnore it, and another is to iterate through all the top level instances to hide the child instance within each of them.

  • I think the best way to achieve this is not to update the schematic to ignore a specific instance, but instead to use a config view in the hierarchy editor, and then to use the config view in ADE for simulation. If it's an AMS simulation, you need to do this anyway.

    You can then set a cell binding on the block in question or an instance (or occurrence) binding in the tree view to set the instance to "Bind to Open" (right mouse button menu over that cell or instance in the tree view, much as you might set a "view to use"). That will get that block to be omitted from netlisting and hence omitted from simulation - but the core database doesn't need to be edited. This seems a much cleaner way of achieving what you want, as other users or usages will still have the analog block you mention present.

    Regards,

    Andrew

  • in reply to Andrew Beckett

    This is perfect, exactly what I was looking for, thank you!!

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