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  3. CDF Parameter Passing to the Netlist

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CDF Parameter Passing to the Netlist

gintel
gintel over 12 years ago

Here is my problem:

 I would like to create the hspiceD (or spectre, doesn't really matter) netlist for a circuit, let us call it depth0. This circuit has a subblock, i0, which is an instance of cell depth1. Inside depth1, there is a resistor and a capacitor. In addition, depth1 has a parameter called myParam (defaults to 1) that I would like to pass to the netlist. In other words, I would like to create a netlist like this:

.subckt depth1 in out
* INPUT:  in
* OUTPUT:  out
* ----------------------------
*.PININFO  in:I
*.PININFO  out:O
* ----------------------------
r0 in out 1e3
c0 out 0 1e-12
.ends depth1

.subckt depth0 in0 out0
* INPUT:  in0
* OUTPUT:  out0
* ----------------------------
*.PININFO  in0:I
*.PININFO  out0:O
* ----------------------------
xi0 in0 out0 depth1 myParam=1

.ends depth0
.end

To achieve this, I have edited the CDF parameters of depth1 (Scope:Cell, Layer:Base). I added a parameter called myParam, type:String, Default Value:1, Parse as CEL:yes, Parse as Number:yes, Store Default:yes. When I build the dept0 schematic and add the depth1 symbol, I can see the myParam parameter in the symbol view. In the Simulation Information of the CDF parameters window, in hspiceD simulator, I added myParam in instParameters section.

When I netlist, I do get the netlist above without the myParam value. In other words, the bold line above in the actual netlist is this:

 xi0 in0 out0 depth1

If in the stop view list, I put schematic, then I do get the bold line as I want, (i.e. xi0 in0 out0 depth1 myParam=1), but then the netlister does not descend into i0, and the netlist file does not include the depth1 subckt at all.

Is there a way to keep both the parameter value and the subckt information in the netlist?

Thanks.

 

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  • Andrew Beckett
    Andrew Beckett over 12 years ago

    You need something in the schematic to actually use the parameter - e.g. set the resistor value to 1e3*pPar("myParam") - and then it should get netlisted.

    Andrew.

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  • Andrew Beckett
    Andrew Beckett over 12 years ago

    You need something in the schematic to actually use the parameter - e.g. set the resistor value to 1e3*pPar("myParam") - and then it should get netlisted.

    Andrew.

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