Question for noise source

Hi all, I am a new user of Cadence. I need to generate a noise source
for my simulation because no noise source could be found in analoglib.
Could anyone tell me how to have a noise source? I just got an idea
that I could use Matlab to generate a random number set and transfer
into Cadence as a noise source but I do not know how to input the
Matlab file into Cadence to become an component to use. It is better
if there are other easier way to make it. Thanks for help.

 

you can generate small-signal noise sources (noise/pnoise simulation)
with a veriloga block.
There are 3 functions defined in veriloga to generate noise:
- white_noise( power [ , "name"]) : generate white noise
- flicker_noise( power, exp [ , "name"]): generate pink noise 1/f^exp
- noise_table(vector [ , "name" ]): piece-wise description of noise
spectral density.

Have a look at the veriloga section in cadence's documentation for
more details.

You can also generate noise with an analogLib resistance providing
4kTR white noise
(there is a parameter to enable/disable noise).

To generate a "noisy" signal in large-signal simulations (tran), you
can generate a random
signal with a veriloga block using one of following functions:
$random, $rdist_uniform,
$rdist_normal ...

 

Also, the sources in analogLib (vsource, isource, port) have the means of
specifying a noise file, with noise versus frequency values.

Regards,

Andrew.