Changing a parameter in the PDK model file using Variable in ADE

My guess is that the model file is also defining the same parameter, and has set it so that redefinedparams is ignore or warning. Because of this, whichever is defined last wins.

If you use:

envSetVal("spectre.envOpts" "netlistModelFileFirst" 'boolean t)

before starting ADE (this could go in your .cdsinit file), then it will put the model file include before the parameters statements, and so your ADE variables will win over those defined in the model files.

This option was added in (I believe) IC615 ISR3 (6.1.5.500.3). 

Regards,

Andrew.

Dear Andrew,

Thanks a lot for your reply.

No,

Actually the Model Verilog-A model portion contains a variable as :-

parameters hfn_flag= hfnoise.

And if you open the pCell corresponding to the file, you will see hfn_flag -> 0 or 1 option which one can change manually for the Cell while instantiating.

I put hfnoise as a parameter in Design Variable expecting that netlist will take hf_noise paarmeter value . But Alas !! that is NOT happening.

If that's in the verilogA, then it's a syntax error - it would be parameter not parameters (maybe that's just a typo when you typed it into the forum). Whether it is is in VerilogA or Spectre, hfnoise must be defined somewhere before it is used - so that's the key to this. That said, if it is a VerilogA variable, then this is a different namespace from spectre parameters - so setting it from spectre (and hence ADE) may not be so easy - but it's really hard to tell without seeing the model files.

Best solution is to contact customer support so that we can see the models (either if they're your own, or by knowing the exactly foundry PDK so that we can request access to it).

Regards,

Andrew.