How can I give Addictive White Gaussian Noise(AWGN) as an INPUT?

Surya,

In analogLib, you could use vsource. Vsource has a number of options to add random noise. Check out parameters isnoisy, noisefile, noisevec, noisetype, noiseinterp, rjseed rjrms, pjamp, pjfreq, pjtype.

You could also use a VerilogA model:

`include "disciplines.vams"
`include "constants.vams"

module noisesrc (op);
output op;
electrical op;

analog begin
  @(initial_step) $display("Noise arg is ",sqrt(4*`P_K*$temperature*50.0),"V/sqrt(Hz)");
  V(op) <+ white_noise(4*`P_K*$temperature*50.0);
end

endmodule

This is a small signal noise source for "noise" analysis. If using transient, you could use a verilogA model using $rdist_normal() - but not sure what your requirements are (you could also use transient noise with one of the above sources).

Regards,

Andrew.

Andrew, 

Thank you for your reply. 

I am using transient analysis and I want to check my design by giving Addictive white gaussian noise(AWGN) as an input.

When I select Vsource from the analoglib, it is not giving me all those parameter you mentioned above

Here I don't understand what to choose in Noise entry method (File or Noise/Frequency points).

and the above model You gave is for the noise analysis, but what changes do I have to make to use it in transient analysis and where should I include $rdist_normal() in the Code.

Surya.

Surya,

Probably the simplest is for you to be using a recent enough version of both the IC tools and MMSIM so that the prbs (Pseudo-Random Binary Source) options are available?

Also, the Verilog-A code I gave will work if you enable transient noise. I don't have time right now to produce an example using $rdist_normal.

Regards,

Andrew.

Andrew,

My IC version is 615, and the version of MMSIM is 10.1, I still can't find the "inoisy" plugin. and when i try to add noise/freq pairs, the transient simulation result shows that the added information doesn't make effect. So how could i get a white Gaussian noise added to a supply source when doing transient simulation? Only verilog-A model?

BTW, I'm doing a PLL simulation, and I want to know the effect of supply noise on PLL's output 's jitter performance. 

Hoping your reply!

Thanks!

I'm sure this should work because vsource has supported isnoisy (not that you'd have to set it anyway, because provided you've set the noise source parameters and are actually running transient noise, this should work).

So what does your tran analysis statement look like in the input.scs file?

Regards,

Andrew.