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Modified parameters don't change layout pcells

egolowen

Hi,

I am writing SKILL code in order to modify the parameters of layout instances, however even though the parameter has been properly modified, the layout pcell does not change (for example, if I increase the length of an nfet the property is the correct value but the layout instance remains the same size).

 I have tried using:
  foreach(prop properties
... 
prop~>value = param_value
...
)

and:
 dbReplaceProp(inst prop~>name 'string param_value)

But neither have fixed the issue.
Is there a better may to modify these parameters so the layout itself is updated properly? I was thinking of trying to use a replay file but that may not do the trick.

Thanks,
Elizabeth

Parents

  • Anand,

    The first thing is to determine what the PCell parameters are actually called, and what type they are, and whether they are the same as the CDF parameters. Sometimes there are CDF parameters which you set, and then the CDF callbacks set the pcell parameters.

    To find out the pcell parameters on the instance, I suggest you select the instance and then execute:

    foreach(mapcar prop car(geGetSelSet())~>master~>parameters~>value list(prop~>name prop~>value prop~>valueType))

    This will output something like:

    (("fingers" 2.0 "float")
    ("tap" "Integrated" "string")
    ("fw" 4e-07 "float")
    ("l" 4.5e-08 "float")
    ("connectGates" "None" "string")
    ("connectSD" "None" "string")
    ("switchSD" "FALSE" "boolean")
    ("diffCont" "TRUE" "boolean")
    ("dfm" "Minimum" "string")
    ("mtlCvg" "" "string")
    ("sdMtlWidth" 6e-08 "float")
    ("leftAbut" 0 "int")
    ("rightAbut" 0 "int")
    ("topTap" "FALSE" "boolean")
    ("bottomTap" "FALSE" "boolean")
    ("leftTap" "TRUE" "boolean")
    ("rightTap" "FALSE" "boolean")
    ("tapExtension" "" "string")
    ("tapCntRows" 1 "int")
    )

    You could compare this with the default values (I highlighted in red the difference):

    foreach(mapcar prop car(geGetSelSet())~>master~>superMaster~>parameters~>value list(prop~>name prop~>value prop~>valueType))

    You can also then compare with the CDF parameters:

    foreach(mapcar param cdfGetInstCDF(car(geGetSelSet()))~>parameters list(param~>prompt param~>name param~>value param~>paramType))

    (("Model Name" "model" "g45p1svt" "string")
    ("Multiplier" "m" "1" "string")
    ("Simulation Multiplier" "simM" "iPar(\"m\")" "string")
    ("Length" "l" "45n" "string")
    ("Finger Width" "fw" "400n" "string")
    ("Total Width" "w" "800n" "string")
    ("Simulation Width" "simW" "400n" "string")
    ("Fingers" "fingers" "2" "string")
    ("AreaFormula" "AreaFormula" "((iPar(\"fingers\")+1)*0.5u+iPar(\"fingers\")*iPar(\"l\"))*(iPar(\"fw\")+0.5u)*iPar(\"m\")" "string")
    ("Folding Threshold" "threshold" "10u" "string")
    ("Diff Cont" "diffCont" t "boolean")
    ("Gate Connection" "connectGates" "None" "cyclic")
    ("Use DFM Rules" "dfm" "Minimum" "cyclic")
    ("S/D Metal Width" "sdMtlWidth" "60n" "string")
    ("S/D Connection" "connectSD" "None" "cyclic")
    ("Switch S/D" "switchSD" nil "boolean")
    ("Metal Coverage" "mtlCvg" "" "string")
    ("Left Abutment" "leftAbut" 0 "int")
    ("Right Abutment" "rightAbut" 0 "int")
    ("Bodytie Type" "tap" "Integrated" "cyclic")
    ("Left Tap" "leftTap" t "boolean")
    ("Right Tap" "rightTap" nil "boolean")
    ("Bottom Tap" "bottomTap" nil "boolean")
    ("Top Tap" "topTap" nil "boolean")
    ("Tap Extension" "tapExtension" "" "string")
    ("Tap Contact Rows" "tapCntRows" 1 "int")
    ("Show Sim Parameters" "showSimParams" nil "boolean")
    ("Edit Area & Perim" "editAreaPerim" nil "boolean")
    ("Drain diffusion area" "ad" "56f" "string")
    ("Source diffusion area" "as" "56f" "string")
    ("Drain diffusion periphery" "pd" "1.08u" "string")
    ("Source diffusion periphery" "ps" "1.08u" "string")
    ("Drain diffusion res squares" "nrd" "0.35" "string")
    ("Source diffusion res squares" "nrs" "0.35" "string")
    ("Left S/D Length (SA)" "sa" "140n" "string")
    ("Right S/D Length (SB)" "sb" "140n" "string")
    ("Gate Spacing (SD)" "sd" "160n" "string")
    ("SCA" "sca" "100.511" "string")
    ("SCB" "scb" "0.07485" "string")
    ("SCC" "scc" "0.01118" "string")
    ("Drain diffusion length" "ld" "" "string")
    ("Source diffusion length" "ls" "" "string")
    ("Device initially off" "off" nil "boolean")
    ("Drain source initial voltage" "Vds" "" "string")
    ("Gate source initial voltage" "Vgs" "" "string")
    ("Bulk source initial voltage" "Vbs" "" "string")
    ("Temp rise from ambient" "trise" "" "string")
    ("Source/drain selector" "geo" "" "string")
    ("Additional drain resistance" "rdc" "" "string")
    ("Additional source resistance" "rsc" "" "string")
    ("Temperature difference" "dtemp" "" "string")
    ("PAS Update Param List" "pasUpdateParamList" "fw, l" "string")
    )

    As you can see in my example, there are many more CDF parameters than pcell parameters.

    When you do your dbReplaceProp, if you are settings the PCell parameter directly and it has the right type, you should see the effect - assume that the PCell actually takes note of that parameter. If you need to call the callbacks (generally needed if the parameter names don't match between CDF and PCells, or if more than one PCell parameter changes when you change the parameter on the edit properties form), then you'd also then need to call:

    instId=car(geGetSelSet())
    abInvokeInstCdfCallbacks(instId)

    or the CCSinvokeInstCdfCallbacks equivalent - to make everything update as if you'd done it through the edit properties form.

    Hope this helps a bit!

    Regards,

    Andrew.

Reply

  • Anand,

    The first thing is to determine what the PCell parameters are actually called, and what type they are, and whether they are the same as the CDF parameters. Sometimes there are CDF parameters which you set, and then the CDF callbacks set the pcell parameters.

    To find out the pcell parameters on the instance, I suggest you select the instance and then execute:

    foreach(mapcar prop car(geGetSelSet())~>master~>parameters~>value list(prop~>name prop~>value prop~>valueType))

    This will output something like:

    (("fingers" 2.0 "float")
    ("tap" "Integrated" "string")
    ("fw" 4e-07 "float")
    ("l" 4.5e-08 "float")
    ("connectGates" "None" "string")
    ("connectSD" "None" "string")
    ("switchSD" "FALSE" "boolean")
    ("diffCont" "TRUE" "boolean")
    ("dfm" "Minimum" "string")
    ("mtlCvg" "" "string")
    ("sdMtlWidth" 6e-08 "float")
    ("leftAbut" 0 "int")
    ("rightAbut" 0 "int")
    ("topTap" "FALSE" "boolean")
    ("bottomTap" "FALSE" "boolean")
    ("leftTap" "TRUE" "boolean")
    ("rightTap" "FALSE" "boolean")
    ("tapExtension" "" "string")
    ("tapCntRows" 1 "int")
    )

    You could compare this with the default values (I highlighted in red the difference):

    foreach(mapcar prop car(geGetSelSet())~>master~>superMaster~>parameters~>value list(prop~>name prop~>value prop~>valueType))

    You can also then compare with the CDF parameters:

    foreach(mapcar param cdfGetInstCDF(car(geGetSelSet()))~>parameters list(param~>prompt param~>name param~>value param~>paramType))

    (("Model Name" "model" "g45p1svt" "string")
    ("Multiplier" "m" "1" "string")
    ("Simulation Multiplier" "simM" "iPar(\"m\")" "string")
    ("Length" "l" "45n" "string")
    ("Finger Width" "fw" "400n" "string")
    ("Total Width" "w" "800n" "string")
    ("Simulation Width" "simW" "400n" "string")
    ("Fingers" "fingers" "2" "string")
    ("AreaFormula" "AreaFormula" "((iPar(\"fingers\")+1)*0.5u+iPar(\"fingers\")*iPar(\"l\"))*(iPar(\"fw\")+0.5u)*iPar(\"m\")" "string")
    ("Folding Threshold" "threshold" "10u" "string")
    ("Diff Cont" "diffCont" t "boolean")
    ("Gate Connection" "connectGates" "None" "cyclic")
    ("Use DFM Rules" "dfm" "Minimum" "cyclic")
    ("S/D Metal Width" "sdMtlWidth" "60n" "string")
    ("S/D Connection" "connectSD" "None" "cyclic")
    ("Switch S/D" "switchSD" nil "boolean")
    ("Metal Coverage" "mtlCvg" "" "string")
    ("Left Abutment" "leftAbut" 0 "int")
    ("Right Abutment" "rightAbut" 0 "int")
    ("Bodytie Type" "tap" "Integrated" "cyclic")
    ("Left Tap" "leftTap" t "boolean")
    ("Right Tap" "rightTap" nil "boolean")
    ("Bottom Tap" "bottomTap" nil "boolean")
    ("Top Tap" "topTap" nil "boolean")
    ("Tap Extension" "tapExtension" "" "string")
    ("Tap Contact Rows" "tapCntRows" 1 "int")
    ("Show Sim Parameters" "showSimParams" nil "boolean")
    ("Edit Area & Perim" "editAreaPerim" nil "boolean")
    ("Drain diffusion area" "ad" "56f" "string")
    ("Source diffusion area" "as" "56f" "string")
    ("Drain diffusion periphery" "pd" "1.08u" "string")
    ("Source diffusion periphery" "ps" "1.08u" "string")
    ("Drain diffusion res squares" "nrd" "0.35" "string")
    ("Source diffusion res squares" "nrs" "0.35" "string")
    ("Left S/D Length (SA)" "sa" "140n" "string")
    ("Right S/D Length (SB)" "sb" "140n" "string")
    ("Gate Spacing (SD)" "sd" "160n" "string")
    ("SCA" "sca" "100.511" "string")
    ("SCB" "scb" "0.07485" "string")
    ("SCC" "scc" "0.01118" "string")
    ("Drain diffusion length" "ld" "" "string")
    ("Source diffusion length" "ls" "" "string")
    ("Device initially off" "off" nil "boolean")
    ("Drain source initial voltage" "Vds" "" "string")
    ("Gate source initial voltage" "Vgs" "" "string")
    ("Bulk source initial voltage" "Vbs" "" "string")
    ("Temp rise from ambient" "trise" "" "string")
    ("Source/drain selector" "geo" "" "string")
    ("Additional drain resistance" "rdc" "" "string")
    ("Additional source resistance" "rsc" "" "string")
    ("Temperature difference" "dtemp" "" "string")
    ("PAS Update Param List" "pasUpdateParamList" "fw, l" "string")
    )

    As you can see in my example, there are many more CDF parameters than pcell parameters.

    When you do your dbReplaceProp, if you are settings the PCell parameter directly and it has the right type, you should see the effect - assume that the PCell actually takes note of that parameter. If you need to call the callbacks (generally needed if the parameter names don't match between CDF and PCells, or if more than one PCell parameter changes when you change the parameter on the edit properties form), then you'd also then need to call:

    instId=car(geGetSelSet())
    abInvokeInstCdfCallbacks(instId)

    or the CCSinvokeInstCdfCallbacks equivalent - to make everything update as if you'd done it through the edit properties form.

    Hope this helps a bit!

    Regards,

    Andrew.

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