In my defense: I did the math myself and I searched the forums before asking.
If the LED's forward voltage at 1A is 3.7V (as listed for the single green Cree XP-E2) then no resistor is necessary. Correct?
Math:
Ω = (3.7V - 3.7V)/1A = (0)/1 = 0
W = 0Ω x 12A = 0 x 1 = 0
On the Tri-Cree listing it says 3.58Vf for green, which leaves me at 0.12Ω at 0.12W.
Math:
Ω = (3.7V - 3.58V)/1A = (.12)/1 = .12
W = 0.12Ω x 12A = .12 x 1 = .12
That's a much smaller resistor than anything I've seen anybody use. Am I doing something wrong, or do I really need a teeny-tiny (or no) resistor for a green Cree?
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