Luxeon mods reverse polarity protection

Does anyone know what kind of diode to use for reverse polarity protection in an ls mod? Are there any drawbacks to using one or is there any resistance in one? Thanks for any help you may have.

The drawback is that it will "drop" or "consume" about .7V from your circuit. If you are running off of "extra" batteries and have the current to spare too, it can be a good thing.

But in general, I'd say you are better off either designing for polarity protection through a mechanical means, or just be darn careful when you insert batteries.

If you use one, be sure that it will handle the power that is drawn through it: On one of my first LS designs (running from a 4V Lead Acid battery) I used one INTENTIONALLY to drop the .7V, however the one I used was too small and it burned out AFTER I had "potted" it in epoxy. What a mess.

I say test the LED at a voltage that is significatly lower that max (rated input coltage) to dertermine polarity (just enough to get some glow). Screw that diode stuff...

If you're tryin for figure out a Luxeon, the solder pad with the "dot" net to it is is the + terminal..

Thanks for the input guys. I believe I will stick with being careful when I change batteries, along with a green dot facing up when I have my battery holder in right, and a red dot on the opposite end when the battery holder would be in wrong!