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Simulators >> RF Simulators >> Transient Analysis for VCO
https://designers-guide.org/forum/YaBB.pl?num=1224748107

Message started by gorkhim on Oct 23^rd, 2008, 12:48am

Title: Transient Analysis for VCO
Post by gorkhim on Oct 23^rd, 2008, 12:48am

Hello,
I have been using spectre to simulate VCO with nano-wire transistors for Transient analysis. I have been getting following warning over and over:

I1.Q1.Mpx: Parasitic resistor 'bias independent gate resistance' has been deleted because its value of 42 mohm (R / MFactor) was smaller than 'MinR' .

Simulation is very slow.
Does anyone have any solution for it? Is this serious problem? Please help....Really appreciated.
Thank You

Title: Re: Transient Analysis for VCO
Post by jbdavid on Dec 18^th, 2008, 7:59pm

Without access to information on the technology you are using and the circuit you are using, I don't think a good engineering judgement is possible. but if you have lots of these errors, I would be guessing that you have a LOT of devices in your design, most of which are parasitic.. and the setting you are using are telling the simulator to treat as Shorted any resistor that is too small .. If you LOWER the number (to make the warnings go away) then you will have even more devices and the simulation will run even SLOWER..

Now you have to put your engineering hat on and decide what is "close enough" .

jbd