Junction Noise

[Martin Czech]

:::I have a 24 bit unit clocked from a VCO that has no automatic
:::"forbidden" state fixer.  I have a reset switch that I have used only
:::once when troubleshooting it.  The math says that if the unit
:::is well constructed, there should be no possibility of locking up.
:::I've used mine for hours and hours and never had a problem.

sure. For audio purposes there may be no need for a false mode
detector. If the noise stops, give it  a reset. OTOH for serious
applications such a detector is a must. Any circuit I design here will
NOT pass any design review if I can't prove how the system will get out
of such a trap, with good reason. We had several cases of grief were
such locking up causes "crash" of a chip.

You can not say by math that the false state will never be, instead you
can predict the propability.

And if it happens only once in week, it's even worse!  How long will you
need to find such a design flaw, if it takes a week to get the system
into the "funny" mode.

Avoiding the false state was not the main idea of feeding
analog noise into the shift register. The idea was to
improove statistical or spectral behaviour by "scrambling",
as well as artificial sound effects, and having FIR
filtering as well...

This may be interesting for very low frequencys where analog
filters are difficult to realize...

m.c.