On 2 Maio, 19:07, Riad KACED <riad.ka...@[EMAIL PROTECTED]
> wrote:
> Hi There !
>
> The Last time I worked with this AMS 0.35u process was when at the
> uni ... ages ago !
> So I don't really know what's the VT value on this PDK but I can give
> you a hint to get it yourself without asking anybody but your best
> ever companion for this kind of requests : Spectre !
>
> 1. A MOS is operating in saturation mode when both of the following
> conditions are satisfied :
> Cond_1: VGS > VTH
> Cond_2: VDS > (VGS-VTH)
>
> That's of course for N-type Fets, just reverse it for the P ones.
>
> 2. To get your VTH from Spectre, just run a DC OP on your schematic
> and the go to :
> Analog Design Environment Window -> Results -> Print -> DC Operating
> Point
> This menu should be active (not grayed) if you've already done a DC
> (with saving OP points) simulation.
>
> So when you hit this 'DC operating Points' menu, Cadence comes with a
> blank window called 'Results Display Window'.
> This window is empty so far because it's waiting for you to select the
> device from the schematic.
> If you give a look at the bottom left corner of your current schematic
> window, you should see the following message :
> Ready> select instances for the MP output ...
> You know then what you do ! Just hit that device and you get your
> Rsults display window nicely decorated !
>
> You will find there all the outputs you need for your transistor,
> including the VTH
>
> This is the simplest way for you to get the VTH
>
> There are other ways to print this value if don't like the GUIs but I
> don't recommend it for you.
>
> BTW, among this huge list of output parameters, there is one that
> could interests you : "region"
> I'm not gonna tell you what it is, just search in the Spectre
> do***entation and you will understand why I'm talking about it ...
>
> Enjoy yourself !
>
> Riad.
Hi!
I knew the Results Display Window. And I've already done what you
said.
The problem is when I want to dimension a MOS with a current and vgs
defined. If it's in the saturation region, I'll just need the
threshold voltage.
Furthermore, when I look to the vth in the results I see that it isn't
constant because it depends on a lot of things.
I thing that I have to study tthe Spectre Do***entation, as you advice
me.
Thanks again
Sara
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