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  3. Problem in plotting Cgs vs Vgs

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Problem in plotting Cgs vs Vgs

anhnha
anhnha over 11 years ago

Hi.
I need to plot Cgs vs Vgs of a NMOS transistor. I have searched a lot and followed tutorial but still in vain. Below is my circuit for simulation. My schematic and setting is attached in the picture below. Here, I chose DC analyse, with Vgs sweeping from 0 to 2V.
I created a file, namely, oppoint.scs, and wrote its content as follows:
save M2:oppoint

Then I chose Netlist and Run.

However, the error below appeared.
(please see the attached file in the second post. I can't post two images in a single post).

I couldn't figure out why. I am completely new with Cadence and I can't use SKILL.
Hope you can help.
Thanks.

 

  • Cgs simulation.png
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  • anhnha
    anhnha over 11 years ago

     Here is image about the error:

     

    • error Cgs simulation.png
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  • Andrew Beckett
    Andrew Beckett over 11 years ago

    From the error message, you have also filled in the "Stimulus File" field in the Setup->Simulation Files form (as well as on the model libraries). The error message you show happens if you have got the path incorrect or the permissions are such that the file cannot be read.

    You don't need to specify it on the Stimulus File field and the Model Libraries - one is enough (otherwise it will get included twice), but in either case you need to ensure that the pathname is correct. In a UNIX window, check:

    ls -l /home/HuanNV/Desktop/oppoint.scs

    Does it exist? Is it readable by the user in question? Try doing "cat" on the same file to see if you can read the contents. If you only specified it on the Model Libraries form and the file didn't exist or wasn't readable, you'd get a message in the simulation log file:

    Error found by spectre during circuit read-in.
        ERROR (SFE-868): "input.scs" 10: Unable to open input file `/home/HuanNV/Desktop/oppoint.scs'.
            No such file or directory.

    Regards,

    Andrew.

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  • anhnha
    anhnha over 11 years ago

     Hi.

    Thanks a lot for the answer. You are right, The path is correct. However, the name of that file is incorrect. It has a space at the end and that makes it hard to debug.

    Now I have just completed Netlist and Run.  From ADE, I go to Tools ->  Results Browser and got the Results Browser wizard.

    I don't know how to plot Cgs vs Vgs next. Could you help me?

     

    • Results Browser.png
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  • anhnha
    anhnha over 11 years ago

     I figured it out. Just browses to these folders. Thank you.

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