Independent noise sources in Orcad.

What kind of part, BJT, MOSFET ?? Or a system?

Resistor, diode ??

...Jim Thompson

Ok, what type of noise source? White, pink, grey? What bandwidth? Is this for an AC or transient simulation? How long are you simulating?

When you can answer all these questions, then you are ready to design your own. No one noise source will do answer all of these, so they never tried to design one. There is an app note on using a PRN generator to write to a file to be used as a noise source in conjunction with a Vpwl source. Or, just get your own list of random numbers...

Charlie

Thanks for the replies.

I wanted to get a source of white noise, but inserting the resistor will affect other important parameters of the circuit, such as I/V. What I really want is a component which does nothing other than produce I or V noise in frequency domain.

I am doing an AC sweep, from 10kHz to 1MHz, flicker noise contribution can be ignored.

Random number generator will not work, because as I understand it, it will not be analyzed by PSPICE noise solver. It will simply show up on the output as random variation.

• its for time-domain, which I don't need.

Maybe use a resistor thru a behavioral E or G block?

...Jim Thompson