RTL Logic

From: der Mouse <mouse_at_Rodents.Montreal.QC.CA>
Date: Fri Jan 7 21:57:55 2005

> Doesn't 4000-series CMOS logic operate pretty well at non-5 volt
> levels if powered to such levels?

Which brings up something I've wondered about for a long time: what
goes wrong with TTL when powered at other than 5V? "It doesn't work",
yes, but _why_? I've got schematics for many of the simpler circuits
in my data book, and I can't see anything there that I wouldn't expect
to work equally well at anywhere from 3 volts or so up to the point at
which either currents get so high that dissipated power cooks something
or insulating layers break down, whichever happens first.

So there's obviously something I don't quite understand going on, and
there are few better places to learn such things than here. :-)
Besides, the data book itself, never mind the parts described in it, is
on topic by now. Heck, I personally used it in the late '70s.

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Received on Fri Jan 07 2005 - 21:57:55 GMT