B
[email protected]
- Jan 1, 1970
- 0
Jim said:Of course, at my age that's just yesterday ;-)
This one. However a lot of those faster devices were cantankerous as
hell to keep from oscillating... the MC1650/51 never was... and I
designed it ~1965.
I certainly had enough trouble sorting out other people boards where
LM311's were cantankerous, but the first Am685 I ever designed onto a
board - back in 1975 - never showed any sign of oscillating, and the
AD96685s never gave us any trouble in 1989 (though at least one of the
boards did turn out to be virtually useless because the printed circuit
department "knew" that the order of the four inner layers of the board
didn't matter, and didn't pass on my instructions on the build-up to
the manufacturer).
I personally checked out the layouts around every comparator on every
one of our (three) double extended Eurocards, but I don't remember
having to ask for more than minor nit-picking changes which could be
done on the spot.
There are a few simple rules for laying out fast comparators - starting
with "keep the outputs well away from the inputs" - and you don't have
to learn them from experience.