James Sweet wrote:
stoneattic wrote:
James T. White wrote:

"stoneattic" wrote in message
groups.com

See page 11 of the spec sheet. VF(typ) = 4.1V @ IF = 112ma.

So you will need a series resistor sized to drop .9V at 112ma.

--
James T. White



Thanks! That's actually what I thought but I wasn't sure I was reading
that correctly on the spec sheet. So an 8 ohm resistor is the way to
go? I assume a 1/4w would be fine?

Thanks again



In a pinch you can start with a 500 ohm or so pot, then set it to max
resistance, measure the current with a DMM and adjust the pot to get the
desired current/brightness and then disconnect the pot, measure the
resistance of that and choose a fixed resistor as close as you can get.
1/4W should be plenty, 1/8W should work too.

Since I use this thing in the dark mostly I would lean towards the
brightest I could get out of it which would be at a resistance of 0.
hehe Obviously that's not a good idea. Do you think the 8 ohms would
give me the best brightness and still protect the LED enough? I've got
10ohms resistors (1/8 and 1/4W) laying around so I may toss one of
those in and call it done. How does that sound?

Thanks again!