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 How to know that ALL MOS are in saturaion region by running ocean script? 

Last post Tue, Jul 9 2013 9:07 PM by MOSMOS. 5 replies.
Started by MOSMOS 07 Jul 2013 03:13 AM. Topic has 5 replies and 817 views
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  • Sun, Jul 7 2013 3:13 AM

    • MOSMOS
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    • Points 85
    How to know that ALL MOS are in saturaion region by running ocean script? Reply

    I want to know how to write a ocean script that can create a file to display all MOS' region,but I don't know the function.

    How to know that where are All MOS in ??

    THANKS! 

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    • Post Points: 20
  • Mon, Jul 8 2013 12:03 AM

    • VKhlyupin
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    Re: How to know that ALL MOS are in saturaion region by running ocean script? Reply

     If you mean that you need to determine a region which each MOS in after some simulation, I'm affraid there is no one function to do this and you'll have to read skill docs to obtain a methodology.

    If you are talking about values of the CDF description of each MOS (some CDF descriptions have the "reagion" parameter) I think "dbGet" function coul help you.

    • Post Points: 20
  • Mon, Jul 8 2013 4:41 AM

    Re: How to know that ALL MOS are in saturaion region by running ocean script? Reply

    If you're using OCEAN, and you've run a DC operating point simulation, then you can use the report() function to do this.

    For example:

    analysis('dc ?saveOppoint t)
    run()
    selectResult('dcOpInfo)
    report(?param "region")

    You'll get the region of each device returned as a number. If you look at "spectre -h modelType" - e.g. "spectre -h bsim4" you get:

     1       region=triode     Estimated operating region. Spectre outputs the number (0-4) in a rawfile.
                              Possible values are off, triode, sat, subth, and breakdown.

    and for "spectre -h bjt" you get:

     3       region=fwd        Estimated operating region. Spectre outputs number (0-4) in a rawfile.
                              Possible values are off, fwd, rev, sat, and breakdown.

    So the numbers correspond to the various regions. So for a MOS, 2 means it is in the saturation region.

    The previous reply talking about CDF parameters is not relevant - that was (presumably) talking about the instance parameter region - which is merely a hint to the simulator as to which region the device is in, to help with DC convergence (an option that is rarely set, because it's not that practical to set it on each transistor, and anyway it's not the final region - just a clue to the simulator to tell it (say) that the device is off and hence to expect it to be off when trying to reach DC convergence).

    Regards,

    Andrew.

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  • Mon, Jul 8 2013 8:22 PM

    • MOSMOS
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    Re: How to know that ALL MOS are in saturaion region by running ocean script? Reply

    Thank you,the results are displayed in terminal using your function .But I want to save the results into a text file,can you give me some suggestions?

    like this:

    p=outfile("./region.txt" "a")

    。。。。。。 

    run()

     fprintf(p "%d

    ................................................................ 

     Can i use such a way to write the results into a text file?

    Thank you very much! 

     

     

     


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  • Tue, Jul 9 2013 12:56 AM

    Re: How to know that ALL MOS are in saturaion region by running ocean script? Reply

    ocean> ocnHelp 'report           

    PROTOTYPE     report([?output t_filename | p_port] [?type
                  t_type] [?name t_name] [?param t_param] [?format
                  s_reportStyle] [?maxLineWidth charsPerLine]) => t/nil
    ...

    So you can do report(?output "./region.txt" ?param "region") or report(?output p ?param "region")

    Regards,

    Andrew.

    • Post Points: 20
  • Tue, Jul 9 2013 9:07 PM

    • MOSMOS
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    Re: How to know that ALL MOS are in saturaion region by running ocean script? Reply
    It's kind of you,thank you very much!
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Started by MOSMOS at 07 Jul 2013 03:13 AM. Topic has 5 replies.