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Modeling >> Semiconductor Devices >> MOS RF model parameters
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Message started by OxBox on Oct 30^th, 2008, 5:02am

Title: MOS RF model parameters
Post by OxBox on Oct 30^th, 2008, 5:02am

I have a Spectre model that adds a subcircuit of substrate resistances to my MOS model. Parameters ring, aw, and ax are used to calculate the substrate resistances. I can't find in the spectremod documentation what these parameters represent... Does anyone know what ring, aw, and ax represent in calculating substrate resistances?

Title: Re: MOS RF model parameters
Post by Geoffrey_Coram on Oct 30^th, 2008, 6:23am

I think those are just variables the subckt author used when writing an equation for the substrate resistance. Probably the schematic interface is supposed to have options on the CDF for an instance of that subckt to specify something about the layout of the device. It won't be in the spectre documentation. You might be able to figure it out by looking at the equations or by investigating the schematic symbol and/or its netlisting code.