Seeing noise anlaysis in spectre

Hi all,

I have a circuit , I am doinhg noise analysis in Spectre for it. I want
to see contribution of each component on output noise current, so I
opened result browser after simulation. In this under the noise-noise
they specify component name and for each component there is value. So
it wants to give some info about each component's contribution but I am
not able to understand what these value stand for?
Can somebody help me with this?....

Thank you

Regards
Amit Bansal

 

This is the contribution of each noise source in each device at the _output_ of
the circuit. It's in V^2/Hz (or V/sqrt(Hz) - I forget). Or it would be in A^2/Hz
or A/sqrt(Hz) if the measured output is a current (i.e. you've done a probe
for the output).

Just checked - they'll be in V^2/Hz or A^2/Hz

Regards,

Andrew.

 

Thank you very much for the reply. But I am still confused. I am doing
noise analysis for output current and done a iprobe at the output.
Shdn't the sum of square root of these values be eqaual to the
current value at the output ? I tried to varify the same but it is not
coming true. please comment on this.

regards
Amit

 

Sorry for troubling you , you are absolutely correct that it is
A^2/Hz, I had a flaw in my circuit thats why I was not able to verify
it. it is correct that out = sqrt( component1+component2+.....)

thanks
Amit

 

If you have sourcelink access, you might be interested in my solution number
11025268 - "Worked example of noise calculations in simple circuit"

Regards,

Andrew.

 

I dont have any documentation . But I may be able to help u in some
problem of urs.

 

Hi,

You can goes to Result / Print /Noise summary in the Analog artist menu,
That will open a form which alow you to print all the noise source with
their contribution.
The value will be in V/sqrt(Hz) because the total (integrated) noise will be
equal to Noise * sqrt(bandwidth of the signal).
Good luck