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View Full Version : Yet another RGB(A) LED question...


Bianchi
08-27-2010, 07:47 AM
It's me again. I know you must be tired of my questions regarding RGBA LEDs, but this is the last one...I think. And it's kind of lame, actually.

I plan on building a saber with a LedEngin RGBA and 4.8 V (four NiMH batteries, 1.2 V each). What's the minimum resistance (ohms and watts) necessary not to overheat each die?

I couldn't find this information anywhere.

Thanks in advance.
Skottsaber
08-27-2010, 08:05 AM
Correct me if I am wrong but I think that the only real battery solution for 10w Ledengins is Li-Ion.
Bianchi
08-27-2010, 08:27 AM
I didn't know that.
Rhyen Skytracker
08-27-2010, 01:11 PM
I have used 4 NiMH AA batteries to run 2 die on one before(for purple) and I have even done a 7 color change saber using 4 1.5V AAA akaline batteries and a 1000 mA buck puck. http://forums.thecustomsabershop.com/showthread.php?t=8363 Keep in mind when you use more than 2 die on the LED your runtime will drop pretty quick. I mainly only used 1 or 2 die at a time. That is why most people use the Li-Ion batteries. With the Li-Ion batteries you have the option of wiring the LEDs in series when using 2 dice (which will split the voltage) or in series/parallel using more than 2 dice (which will split the voltage and current.
DJMoonbass
08-27-2010, 11:52 PM
it all depends on how you wire it up man. you may be able to pull this off. since li ions typically put out 2600 mah. but that doesnt mean it can handle the current draw. i dont know about that one. but this is a DIY forum and you need to learn this.

so heres what ill have you do to get he answer you seek. look up all the forward voltages and currents on each die of your LED. now take

4.8 subtracted by each of those Fv and devide it by your current. and that will be your resitor. ohms law man.

its always supply voltage - forward voltage of LED / current draw of LED.

or you can cheat and use this: http://www.thecustomsabershop.com/wiringbuilder/wiring.aspx



and choose the LED thats closest to your individual dies. good luck man.
JamoUp
08-28-2010, 05:37 PM
data sheet: http://www.ledengin.com/products/10wLZ/LZ4-00MA10.pdf