On Wed, 14 Dec 2005 05:45:36 -0700, Wes Stewart wrote:

On Wed, 14 Dec 2005 08:52:14 +0100, Juergen Hannappel
wrote:

Mark & Juanita writes:


[...]

Given the current state of engineering and our level of technology, I'd
be inclined to label this as a design flaw. i.e. Double-E who designed

Given the incredible prive tag of .4 cents for a protection diode you
are sugesting to put the manufacturer out of business by needlessly
increased cost?

There is a design consideration to be considered.

With the ever decreasing operational voltages that newer ICs use, a
diode voltage drop is greater fraction of the available supply
(battery) voltage.

If this is a remote with a 12V battery, then 0.65 V or so isn't a big
factor. However, with some of the new devices running off 3 or few
volts, you're cutting into the supply pretty heavily. A Schottky can
help but it's still an issue.

I believe the OP indicated this was a 9V battery. Still, the trade
between protecting against catastrophic damage in what is a highly likely
event (reversed polarity applied) and having to deal with the voltage drop
to protect against that event seems to come down very heavily on the
protection side.



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If you're gonna be dumb, you better be tough

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