[time-nuts] Re: thermodynamics of time keeping

[Poul-Henning Kamp]

--------
Dana Whitlow writes:
> Perhaps the author is trying to include Schmitt triggers to sort of emulate
> mechanical escapements.
> I've occasionally used the things (Schmitt triggers) to help square up
> sinewaves, but never in a case
> where I was concerned about stability or jitter.
>
> BTW, how do three inverters constitute a Schmitt trigger?

I dont think the important thing is the Schmitt Trigger,
but rather the square wave.

But putting multiple '04 inverters in sequence was a well
known method to shapen flanks, and I have always understood
that as the reason for using three in the xtal clock generator
setup.


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