Dear All,

I am using a 0.18 um process, I am uisng the minimum length devices in my schematic, but when I extract the netlist using the analog enviroment, the netlist takes the default length of the device which is 1um.

How do I change the default length of the device to 0.18um. Please help to acheive this.

Regards,
Prakash.

First question, what do you mean by 'when I extract the netlist'?
Are you doing a simple netlist creation out of the Analog Environment or
do you preforming an parasitic extraction?

Maybe your cell CDF (Component Description Format) is not
defined right.

Modifying the default value of l from your MOS
is the wrong approach.
You rather should check why the local setting of l
was not taken into account.

1. Start form you model file
  there must be something like
  model <modeName> bsim3v3
  if you device refers direct to a model
  or
  subckt <modelName> n1 n2 n3
    parameters w=1u l=1u

For bsim3v3 w and l are defined instance parameters.
For a subcircuit the parameters must be defined in
the parameter list with a default value.

2. Check your cell CDF for the MOS.
  You can do this over the GUI
  CIW->Tools->CDF->Edit..
  Make sure your CDF Tpye is set to 'Base'.
  Check there if you have the parameter l in the
  'Component Parameters' section as well as in
  the 'Simulation Information' for the simulator
  spectre (I assume).
  For the simInfo of spectre l must be also in the list
  of 'instParameters'.

  An optional way of checking the cell CDF is to
  use the SKILL command cdfDump.
  cdfDump( "yourLibName" "./mos.cdf" ?cellName "yourCellName" ?level 'base ?edit t )

 You'll get a textual output you must see something like this for l
 
 cdfCreateParam( cdfId
       ?name           "l"
       ?prompt         "Length (M)"
       ?units          "lengthMetric"
       ?defValue       ""
       ?type           "string"
       ?display        "artParameterInToolDisplay('l)"
       ?parseAsNumber  "yes"
       ?parseAsCEL     "yes"
   )

and

cdfId->simInfo->spectre = '( nil
       propMapping       nil
       namePrefix        ""
       otherParameters   (model)
       instParameters    (w l as ad ps pd nrd nrs m trise region)
       termOrder         (D G S B)
       termMapping       (nil D \:d G \:g S \:s B \:b)
       componentName     someName
   )


You can reload the CDF file with load( ""./mos.cdf" ) after modification.

3. If all is proper defined the netlister should take care of the local setting of l.

Bernd