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badminton

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Transient Noise in Spectre
Mar 21^st, 2007, 8:04pm

Hello all,
� I am designing a low-jitter clock buffer. �For jitter simulation I plan to use the transient noise simulation feature in spectre. �However, I am not very sure how to set the various settings (noiseseed, noisefmax, noisescale, etc.) to obtain a sufficiently accurate simulation of jitter, while minimizing simulation time. �Can anyone give me some pointers? �Thanks!

Sincerely,
Badminton

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Michiel

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Enschede, the Netherlands

Re: Transient Noise in Spectre
Reply #1 - Mar 22^nd, 2007, 4:09pm

badminton wrote on Mar 21^st, 2007, 8:04pm:

Hello all,
I am designing a low-jitter clock buffer. For jitter simulation I plan to use the transient noise simulation feature in spectre. However, I am not very sure how to set the various settings (noiseseed, noisefmax, noisescale, etc.) to obtain a sufficiently accurate simulation of jitter, while minimizing simulation time. Can anyone give me some pointers? Thanks!

Sincerely,
Badminton

I would advise to gain some familiarity with the simulation first. You can start with a simple circuit like an inverter.
-the value of noiseseed is of little importance. Just set it to one.
-set noisefmax to a frequency that is significantly higher than the bandwidth of interest. For a first test you could use 10G
-if you trust your model parameters, set noisescale to one

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badminton New Member Offline Posts: 4	Re: Transient Noise in Spectre Reply #2 - Apr 24^th, 2007, 10:54pm Thanks for the tips. I have some other questions about transient noise simulations: 1. How do the transient noise waveforms compare with the waveforms measured on an actual circuit? In other words, how much can we trust transient noise simulations? 2. How exactly is spectre simulating transient noise?
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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: Transient Noise in Spectre Reply #3 - Apr 25^th, 2007, 3:40am badminton wrote on Apr 24^th, 2007, 10:54pm: 2. How exactly is spectre simulating transient noise? I think there's a whitepaper on this on SourceLink.
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venki_vlsi Junior Member Offline Posts: 29 warangal	Re: Transient Noise in Spectre Reply #4 - May 16^th, 2007, 9:30pm hi, Can u plz send link of that paper. where is source link?i dint get it. plz help me.
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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: Transient Noise in Spectre Reply #5 - May 17^th, 2007, 4:10am http://sourcelink.cadence.com You need to register (meaning, I think, you need to be a Cadence customer.)
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