White Noise Source

24 Stage Linear Feedback Shift Register (LFSR)

This circuit can be used to generate a pseudo-random sequence of 0's and 1's -- that is "white noise" or "static." The schematic shows a 24 stage shift register with XNOR taps at registers 7, 16, 22, and 24 using the Fibonacci configuration. With these taps, the circuit generates a "maximal length sequence" of pseudo random values which repeats only after (224 - 1) clock pulses.

This circuit runs off a regular 9V battery, a real advantage of CMOS logic. Similar circuits can be constructed using the 4014 IC and/or using other lengths and tap points. See my table for some other configurations which use two or four taps.

Questions/Comments to: suits@mtu.edu

There are no pop-ups or ads of any kind on these pages. If you are seeing them, they are being added by a third party without the consent of the author.

Back to Physics of Music Notes
To Suits Page
To PH1090 course page
To MTU Physics Home
Copyright Info