RMS Noise

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keoiuser

Joined: 24 Mar 2008
Posts: 47
Helped: 5

24 Mar 2008 22:34 rms noise

Hi,

I have to apply a 33mV RMS noise in some circuits, i used the .noisetran simulation with eldo but i couldn't repair the value of 33mV in the simulation flow :
I have the frequency band noise, the noise period injection and an unknown coefficient : THN=40000!!

Any idea of the meaning of the value of THN???Or how can I inject the 33mV rms noise in my simu?

Please help, thank you.

safwatonline

Joined: 19 Nov 2005
Posts: 1418
Helped: 172
Location: EGYPT

25 Mar 2008 8:32 noisetran

<sourcename> <node1> <node2> noise <PSD_value> <vf2> <alpha>

where PSD is the thermal noise PSD
and vf2 is the flicker noise value at 1Hz
alpha is the flicker exponent

keoiuser

Joined: 24 Mar 2008
Posts: 47
Helped: 5

25 Mar 2008 10:26 Re: RMS Noise

Thanks for replying,
First, I don't have enough knownelge in noise domain, in my noisetran simulation i have:

DC NOISE THN=40000f FMIN=100K FMAX=100Meg
Where FMIN & FMAX are the frequency band noise, I just want to determine where the value of 33mV rms noise appears?and so i can change its value.

thanks for help

safwatonline

Joined: 19 Nov 2005
Posts: 1418
Helped: 172
Location: EGYPT

25 Mar 2008 11:07 RMS Noise

ok write the following lines:
.NOISETRAN FMIN=100k FMAX=100MEG NBRUN=2 NFREQ=100 AMP=1 SEED=0 NOMOD=0 NONOM MRUN
Noise1 Plus GROUND noise 10.9e-12 0 1

where Plus is the noise source node