Electric Druid Noise1B

With compliments to Tom Wiltshire, from his website www.electricdruid.net:

"Pure white noise generator using an 8 pin PIC 12F675

This pages describes a simple digital noise source that produces pure white noise over the whole audio band - out to more than 40Khz, in fact. With filtering, you can derive pink noise and other colours. The circuit diagram included below was developed from the famous Polyfusion noise generator, and can produce white, pink and infra-red (low frequency) noise.

The noise generator 12F675 PIC microprocessor uses a dual LFSR algorithm which produces a pseudo-random stream of bits at over 90KHz. The bitstream shouldn't repeat for 142 million years, but obviously I haven't checked!"