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CDL netlisting series resistors as multiple instances

RFdog

Greetings,
 
I'm using a standard resistor model with W, L, NumSeries, and NumParallel as parameteres.  All works well on the simulation side.  
 
Due to company guidelines, LVS will not combine series resistor devices.  i.e. if I have 5 series resistors, each of which is 10u x 1u, I must have the exact same in the layout, not just a single 50x1 device.  The problem is that the CDL netlister creates a single 50x1 device which then doesn't match to the 5 10x1 devices in the layout.
 
Other folks here get around the problem by instantiating 5 individual devices in the schematic (each of 1 unit).  Things get pretty messy when the number of series devices gets large, as it often does.
 
Being somewhat new to this company, I think this practice is bizarre, and would like to find a way to force the CDL netlister to look at the number of series resistors (a CDS parameter), and just export them as N unit devices connected in series.  Seems like it could be easily done, but I have no idea how.
 
any help? 
Parents
  • Thanks, Frank. I'm currently using the same work-around you link to, but want to move to something a bit cleaner along the lines of the COS article posted by Quek. Quek -- The COS article is exactly what I need to do, I just need to muddle through getting it working at this point.. Thanks for the link
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  • Thanks, Frank. I'm currently using the same work-around you link to, but want to move to something a bit cleaner along the lines of the COS article posted by Quek. Quek -- The COS article is exactly what I need to do, I just need to muddle through getting it working at this point.. Thanks for the link
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