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Bus-expansion-like trick for an array of design variables

fastandig

I am using IC 5.1.

I create 64 voltage sources by first creating a single one, then copying it, pressing F3 and then entering 63 in the "columns".

I assign 64 net names by using bus expansion so then i get something like inp<0>, inp<1> ..... inp<63>.

The tools allow me to do the above quickly without manually having to draw so many voltage sources or naming so many nets one by one.

So I was wondering if there's a way I can assign 64 such design variables to the 64 dc voltage sources, lets call them inp_var<0>, inp_var<1>.... inp_var<63>, without having to manually pull up the property box of 64 voltage sources and typing 64 design variable names. Is there a quick way to do this, something like the above bus-expansion way?

Or is the only alternate way is to modify the netlist every time (using some script) before I run monte-carlo simulations for each combination of the 64 voltages? Or any other faster/better solutions?

I think this can be done in IC 6.1 but unfortunately I've to work in IC 5.1 because of legacy circuits, so please let me know if I can do it in IC 5.1. Thank you.

  • Andrew Beckett

    This isn't possible with anything built-in (even in IC6.1.X), but it's easy enough to do with a little bit of SKILL code. For example:

    procedure(CCFsetBusVars(@key (propName 'vdc) (suffix "_var") (instances geGetSelSet()))
    let((varName netName bussedInstTerm)
        rexCompile("^\\([^<]*\\)<\\([0-9]*\\)>$")
        foreach(inst instances
            when(inst~>objType=="inst"
                ;--------------------------------------------------------
                ; Use net name connected to instance to name the
                ; variable, assuming it looks like a bus. Otherwise
                ; base the variable name on the name of the source
                ;--------------------------------------------------------
                bussedInstTerm=
                    exists(instTerm inst~>instTerms
                        rexExecute(instTerm~>net~>name)
                    )
                varName=
                    if(bussedInstTerm then
                        rexSubstitute(strcat("\\1" suffix "\\2"))
                    else
                        strcat(inst~>name suffix)
                    )
                putprop(inst varName propName)
            )
        )
        t
    )
)

    Assuming you've placed all the instances, added the wires and labelled the wires (with bus expansion), and performed a schematic check (to extract the nets), you can then select all the instances (doesn't matter if the wires are selected too), and run CCFsetBusVars(). There are some keyword arguments if the property is not called "vdc" - so for current sources it would be CCFsetBusVars(?propName 'idc)

    Regards,

    Andrew.

  • fastandig
    in reply to Andrew Beckett

    Thank you Andrew, worked very well.

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