View Single Post
  #11   Report Post  
Posted to sci.electronics.design,alt.binaries.schematics.electronic,sci.electronics.basics
RobertMacy RobertMacy is offline
external usenet poster
 
Posts: 732
Default "Random" Circuit Needed.

On Wed, 01 Apr 2015 12:08:34 -0700, Jim Thompson
wrote:

...snip...


"For a simulation situation..." ;-)

John F and Lasse have provided how to do it.

...Jim Thompson



For simulation I'd use the built-in rand() function of LTspice, if you
want gaussian instead of uniform distribution, use five rand()'s summed
appropriately. You said you like to use PSpice only, so create a text file
to use in a PWL type thingy THEN you can get completel control, likw
distribution and the elusive 1/f etc, any type statistics you want.

For Hardware to not have to go buy much, use the Soundcard and run it
directly with either a repeating pattern of random values, or from a
random number generator to get very long runs. The method of converting
FROM the audio output [BW is 10Hz to approx 100kHz] is left to the
'student'] The point here is that you can get repeatable random sequences
that are completely under your control.