Does anyone know how to wire a Cree Xlamp MK-R LED? What size resistor do we need to be inline with the wiring? These are 12v LEDs.

http://www.cree.com/led-components-and-modules/products/xlamp/arrays-directional/xlamp-mkr

Thank you!
Joey

 

It depends, what type of power supply will you use?

These can handle 1.25 amps. They need a big heat sink and DON'T LOOK AT THE LED - the will leave black spots for days and can damage your retinas. Use a diffuser.

If you don't have a diffuser immediately, you can tape it to the bottom of a 20 oz water bottle (lighting the inside of the bottle).

 

I'm building a concept for a lighting system. It has to be super small and bright as heck! I'm planning on using about 4-8 Cree123 3v batteries in series.

Thanks,
Joey

 

'Tools, You didn't understand "they need a big heat sink", did you??

 

If you are just doing a prototype, I'd recommend a constant current power supply. You might do a quick internet search and find a 1A LED power supply pretty easily. I'll also reiterate the previous recommendations due to my experience with LEDs. Careful with your eyes, and careful with the power/heat dissipation or the LEDs will burn up almost instantly.

 

Does anyone know how to wire a Cree Xlamp MK-R LED? What size resistor do we need to be inline with the wiring? These are 12v LEDs.

Joey

Those are NOT 12V LED's.. They have a 11.7V forward voltage.. That is not the same as what would typically be referred to as a 12V LED..
IF I bought a 12V LED I would expect it already had a resistor or other form of current limiting so it can be attached to a 12V constant voltage source..
Its not the same thing..


And you DO NOT use a resistor for LED's like that.. You use a constant current power supply. Why.. because the forward voltage will change with temps and that can lead to drastic differences in the current being supplied to that LED..

and if you don't use a suitable heatsink it will just burn up in a short time..

Stop and learn first..then do it right..

and listen when we say don't look at it.. It can permanently damage your eyes and MUST be used with a proper diffuser/lens and even then DON'T look directly at it unless you are wearing welding goggles.

 

and you would typically buy then preattached to a metal clad circuit board or purchase/design your own board and then reflow solder it to it.. Then thermal compound then heatsink..

Why don't you just buy a cheap Chinese flashlight off ebay?

IMO if you have to ask how to even wire and LED you have no business developing a "concept lighting system"

Sorry if that sounded harsh but there are WAY too many idiots playing with high power LED's now without knowing the basic fundamentals/safety/thermal dissipation,etc.. concepts behind them..

 

Guys, I really appreciate your feedback. I contacted a friend who owns a HUGE company that develops all sorts of things. Instead of doing this myself, I decided to get some pros to help me with it. I can make the business happen, but I need some brainiacs to help me with the concept. Thanks for the assistance. As for the "harsh" comments....I'm a fireman......I can handle it. Leather skin son!

Take care guys.