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Kem

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frequency-dependent parameter in verilog a
May 10^th, 2011, 8:36am

I'm new here and have no experience with verilog a before. I 'm working on a FET transistor model and i have to do it with verilog a. I would like to describe a noise parameter as a function of frequency.

<i_d^2>=4*R*K*T0*B*(w*Cgs)^2 / gm

I would like to know how I can implement a frequency-dependent parameter since verilog a only works in the time domain ?

thanks a lot for your help

kem

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rfidea Senior Member Offline Posts: 159 Europe	Re: frequency-dependent parameter in verilog a Reply #1 - May 10^th, 2011, 8:57am There is a function, flicker_noise(pwr, exp [ , name ]), that you can use for this. There is no limitation for the variable exp so you can use the function for increasing noise with frequency, if you like. By the way, veriloga works both in frequency and time domain.
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Kem New Member Offline Posts: 9	Re: frequency-dependent parameter in verilog a Reply #2 - May 10^th, 2011, 9:03am thanks a lot for your answer! In my case i will do it with white_noise function. Does it means i just have to create a frequency paramerter ? kem
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rfidea

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Re: frequency-dependent parameter in verilog a
Reply #3 - May 10^th, 2011, 9:37am

I do not understand why you should use white_noise if you would like to have a frequency dependent noise source when there is a function for that?

If you need a flat noise response for frequencies above some corner frequency and a 1/f relationship below that corner frequency you can add a white noise source and a flicker noise source by white_noise(..) + flicker_noise(..)

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Kem New Member Offline Posts: 9	Re: frequency-dependent parameter in verilog a Reply #4 - May 10^th, 2011, 12:20pm thanks for your answer. I think i have to use both of them. I have to model the transistor untill ~30 GHz. And the really interessant frequency domain is f>2 GHz
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Kem New Member Offline Posts: 9	Re: frequency-dependent parameter in verilog a Reply #5 - May 16^th, 2011, 9:19am i still haven't solved my problem. The real question is how to model the induced gate noise current of a fet transistor. Are there someone who can help me ? thanks kem
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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: frequency-dependent parameter in verilog a Reply #6 - May 17^th, 2011, 12:51pm Did you look at how correlated noise is done in the MOS11 model, posted on this site? http://www.designers-guide.org/VerilogAMS/semiconductors/mos11010/mos11010.va
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Kem New Member Offline Posts: 9	Re: frequency-dependent parameter in verilog a Reply #7 - May 18^th, 2011, 5:52am Thanks for pointing out the link. I have read it but i couldn't really understand it since there are comment missing. kem
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