> >> Does anybody use these?  Find them at Digikey, or Mouser, or etc?
>
> >Such as the Raychem/tyco "Polyswitch" series, available at digikey/etc.
> >
> >I have some from dumpster diving.  They seem a bit slow to me, taking a
> >couple seconds to open (that may be something you can select, though.)
>
> Yeah, they are really designed as a safety device to handle long term
> overloads, rather than used like a normal fuse. Not sure what the minimum
> current rating is, but I doubt that they will really suit the OP desires.
> There are surface mount ones that might get close though.
>
> The other trick to them is that they are designed to work close to max
> current rating, but if you try and grossly exceed that, then they will act
> rapidly as they then heat up fast. Makes them good for protecting
> transformaers in power supplies from short circuit outputs,
> instead of using
> fuses.

        And they are very good for burning your figures! I was once debugging a
board that wasn't powering up right (it worked one day and they puff,
nothing). We turned it on and observed a full 5V across the power rail along
with a larger then normal current draw. Confused we started poking at things
to see what was drawing the current (the board only had passives on it). I
touched one of these fuses and it was cold to the touch. Went along,
touching things lightly and then touched that polyfuse again (of course, I
didn't KNOW what it was, I though it was a cap or something, didn't think
about what it was). Of course, at this point a few amps had been flowing
through it and suffice it to say it wasn't a pleasant experience! :) TTYL

----------------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.