incorrect extraction issue 

Hi kristen

Thank you very much for the detail explanation. Editing the extracted view manually would always result in "check and save" errors during netlisting. If the extracted view was created using QRC, we can add a callProc.il skillscript in the QRC tech directory to correct the extracted view. When QRC is generating the extracted view, it will read in callProc.il file and pass the cellview ID of the extracted view the script. The script can then search for the appropriate fet and modify its properties.

Unfortunately, your extracted view has been generated using Calibre xRC and hence callProc.il method does not apply. I think it would be better for you to also post your question on Mentor Calibre forum to see if you can get more ideas. If it is ok with you, kindly update this thread with a link to your post on the Mentor forum so that everybody can benefit from your experience. : ) Thanks.

Actually I think the Calibre LVS deck should be corrected to fix this problem. : )  The problem lies with the rule deck and not with extracted view generation. So modifying the extracted view is just a workaround.

A 3rd possible workaround is as follows:
a. Generate a spice netlist using Calibre xRC
b. Use a text editor to correct the fet properties
c. Create a symbol in Virtuoso to represent the netlist and simulate the netlist directly


Best regards
Quek

Hi Kristen

It is possible to run into problems only when generating extracted views and not spectre or spice netlists. This is because when generating extracted view, the device parameters in the parasitic netlist has to match that of the device CDF. E.g. LVS deck extracts a parameter named "W=123u" for fetABC and passes it to QRC(or Calibre xRC). QRC will simply use this parameter when creating the extracted view. But if the CDF info of fetABC is actually looking for a parameter named "width", it will not accept "W" from QRC and will use default value of "width" from CDF. This situation is possible because some pdks do additional mapping from "width" to "w" in CDF.

(CDF : Component Description Format)

Hence a wrong extracted view will be generated. But if we were to simply use a spice/spectre netlist with "W" and not "width", it would simulate well because "W" is what the model file needs.

In the spectre parasitic netlist which you had obtained using Calibre xRC, does it has "simulator lang=spectre" as the 1st line? Is the file named with extension ".sp" instead of ".scs"? It should be named as ".scs".


Best regards
Quek

Hi Kristen

You should use the symbol view. Would you please check the following?

a. Has the spectre netlist been added as one of the model files in ADE-L?

b. Please execute the following in ciw and check the return value:
getShellEnvVar("CDS_Netlisting_Mode")

c. Please upload a snapshot of "spectre" siminfo cdf section


Thanks
Quek

Hi Kristen

Would you please check the following?

a. In ADE-L netlist, does the line for the cell look similar to the following?

I5 (net1 net2 net3 net4) 100GHz_half_backup

If not, how does it look like?

b. Please go to "Setup->Environment". What are the values for "Switch View List" and "Stop View list"?

c. Would you please execute the following cmd in ciw and paste the output?

ddGetObj("Osc_layouts" "100GHz_half_backup")~>views~>name



Thanks
Quek

Hi Kristen

Your setup looks good and it looks like the cell has been netlisted correctly. It is really strange. By the way, may I know the version of spectre which you are using?

terminal>spectre -W

Thanks
Quek

Hi Kristen

Sorry that I am not sure where the problem is. I think it should be just a setup problem because this really cannot be too difficult but it would take a good examination of the actual setup to determine the cause of the problem. I would suggest filing a service request with your nearest Cadence support centre and let an engineer assist you on this. : )

Best regards
Quek