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  3. plot region in mos

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plot region in mos

DanySF
DanySF over 14 years ago

 Hi,

I make a sweep of some parameters (L, and Id) and I want to plot some DCop data .

So I go to Results browser and I search the usual stuff like : gm, vdsat, cgg, cgs.

I can plot also "region" with RMB->Append but if I send the formula to the calculator then I cannot plot it.

 So in the calculator I have something like :

getData("NM0.mn.region" ?result "dc-dc" )

Why this is not working from Caclulator, but is ok when I do RMB->plot ???

I want to save the formula in to a script (Ocean) and I need the formula to work.

Is this a bug or I'm doing something wrong in my setup ?

I have IC5141 with Spectre and Wavescan. My testbench is from 1 nmos and I make a DC sweep with Id and L as parameter.

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  • ywguo
    ywguo over 14 years ago

    Sometimes the tool has weird bugs, especially when we post-process the results. How do you put the formula in the calculator? I will RMB click the signal/parameter in Results Browser, and  choose Calculator. The click the plot button the Calculator to check if the formula is correct. 

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  • ywguo
    ywguo over 14 years ago

    Another point is that this is caused by the pcell and model. Your formula is 

    getData("NM0.mn.region" ?result "dc-dc" )

    It seems that there is a NMOS transistor named mn inside NM0. I mean this is a subckt in the model definition. Sure the foundry or PDK vendor has done something to ensure the correct operation. But this often causes problem when I try to plot operating points in dc sweep or transient simulation. 

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  • DanySF
    DanySF over 14 years ago

     Thanks.

    I checked today the model and indeed there is a subckt inside. Probably this is one of the reason.

    Thanks !

     

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