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Modeling >> Semiconductor Devices >> Flicker noise dependency of VGD?
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Message started by gndod on Jul 8^th, 2004, 6:06am

Title: Flicker noise dependency of VGD?
Post by gndod on Jul 8^th, 2004, 6:06am

Hi,

I'm using the bsim3v3 model and while performing a flicker noise analysis I notice that there is a dependency between the flicker noise and the VGD (=VGS-VDS).
So I could not find which is (or are) the parameter(s) in bsim3v3 model that cause this effect and are they only the flicker noise parameters in the model or there are other that influence?
I only could suppose the bias current or the Coxide...

Thaks a lot.
G.

Title: Re: Flicker noise dependency of VGD?
Post by Geoffrey_Coram on Jul 9^th, 2004, 8:26am

The flicker noise is dependent on the drain current cdrain, which is a function of Vds and Vgs (in forward mode, Vds>0 -- or of Vgd and Vsd in reverse mode), so it is not surprising that you see a dependence on Vgd.

The simplest flicker model in bsim3v3 is NOIMOD=1 or =4, where the power spectral density is KF * |cdrain|**AF / (Cox*Leff*Leff*f**EF)

The more complicated NOIMOD=2 or 3 uses parameters NOIA, NOIB, NOIC, and also depends on cdrain.