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Simulators >> Circuit Simulators >> SpectreMDL: Export result from noise analysis
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Message started by PeterB on Feb 15^th, 2007, 11:36am

Title: SpectreMDL: Export result from noise analysis
Post by PeterB on Feb 15^th, 2007, 11:36am

I want to run a noise analysis inside a MC loop using SpectreMDL.
The noise analysis is working, looks like this:
run noise (iprobe=id1, oprobe=vt1, param=freq, start=1, stop=100, log=3)

but I don't know how to export the noise results (tried something like export n1=in....)

I would be also interested, if it is possible to export values from analyses, which are defined in the netlist ("named analysis).
This would enable pss and pnoise analysis indirectly, correct?

Thanks in advance!

Peter

Title: Re: SpectreMDL: Export result from noise analysis
Post by Scott Flinchbaugh on Feb 21^st, 2007, 4:37pm

Peter,

Here is how you would access noise results from a spectreMDL run. I realize that the documentation is a bit
lacking in this area and will be approved shortly. If you are using MMSIM6.0.2 or later these are available
to you.

In summary there are 4 computed parameters that you can access after a noise analysis is run:
1. Input noise (in)
2. Output noise (out)
3. Noise Factor (F)
4. Noise Figure (NF)

These parameters may be accessed using the following syntax:
<analysis_name>:<noise_parameter_name>

So for your particular case you would construct something similar to the following:

alias measurement my_noise_measure {
export real input_noise, output_noise, noise_factor, noise_figure
run noise (iprobe=id1, oprobe=vt1, param=freq, start=1, stop=100, log=3);
input_noise = noise:in;
output_noise = noise:out;
noise_factor = noise:F;
noise_figure = noise:NF;
}

run my_noise_measure;

Also your observation that the pss and pxf analyses could be run by MDL is indeed correct. There is
no restriction on running the analyses themselves. However, they are not integrated with the analyses, so
you cannot expect to be able to do measurements on their data. For instance, you can run a pss analysis
from an MDL control file, but you would not be able to obtain max(V(node1)) for the pss solution, as the MDL
measurements are ONLY performed for the following analyses:
transient
ac
noise
dc ( and dcsweep )

Thanks,
-scott F.

Title: Re: SpectreMDL: Export result from noise analysis
Post by nube_human on Oct 15^th, 2008, 9:11pm

Hi Scott,

Can you help me with separating out the flicker and thermal components of the noise? I can measure noise with the method you suggest, but can't separate flicker from thermal as the measure statement does not specify which noise is being measured (my guess is total, but could be wrong).

Thanks,
NH

Title: Re: SpectreMDL: Export result from noise analysis
Post by Andrew Beckett on Jan 2^nd, 2009, 3:32pm

Spectre does not provide the total output noise split into flicker, thermal etc components. It does however allow you to find the contribution of each noise source from each device - so you could find the amount of flicker noise contributed by each individual component instead.

Unfortunately Scott passed away in an accident in the middle of 2008. A great loss.

Regards,

Andrew.

Title: Re: SpectreMDL: Export result from noise analysis
Post by nube_human on Jan 5^th, 2009, 11:05am

Thanks for the update Andrew. Sorry to hear about Scott.

NH