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 where can I find the 'rcut' variable to change it? Cadence 6.15.509 

Last post Mon, Oct 22 2012 8:46 AM by zcam. 2 replies.
Started by zcam 20 Oct 2012 07:58 AM. Topic has 2 replies.
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  • Sat, Oct 20 2012 7:58 AM

    • zcam
    • Not Ranked
    • Joined on Wed, Feb 29 2012
    • Posts 7
    • Points 95
    where can I find the 'rcut' variable to change it? Cadence 6.15.509 Reply

    Hi, 

    I have a customized electronic model  for my circuit input. This model contents some resistor larger than 'rcut' which is now equals to 1e12 Ohm in my cadence setup. 

    I guess this limit can be changed. But I couldn't find where to change? Any body has expirences on this?

     

    Thanks

     

    --

    Kangqiao 
    Filed under: ,
    • Post Points: 20

  • Mon, Oct 22 2012 2:21 AM

    Re: where can I find the 'rcut' variable to change it? Cadence 6.15.509 Reply

    I'm assuming you're talking about spectre? If so, this is probably "rcut" as described in "spectre -h options". The default is infinity, except for bsource resistors. Given that  you've not told us much about how this is affecting you, or what the model looks like, I suggest you contact customer support so you can provide some details (if you can't provide them here). There's not normally much benefit in having resistors larger than 1e12 because the default gmin is 1e12 too and so the chances of the resistance having any effect in the solution are pretty small.

    Regards,

    Andrew.

     
    • Post Points: 20

  • Mon, Oct 22 2012 8:46 AM

    • zcam
    • Not Ranked
    • Joined on Wed, Feb 29 2012
    • Posts 7
    • Points 95
    Re: where can I find the 'rcut' variable to change it? Cadence 6.15.509 Reply

    Thank Andrew. 

    I found the rcut option in spectre reference manual.  And tested with for example add something in the option for each analysis:

    rcut=1e14

    which should be large enough for our model. But as you said, the result has nothing changed.  

     

    --

    Kangqiao 
    • Post Points: 5
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Started by zcam at 20 Oct 2012 07:58 AM. Topic has 2 replies.