[ QUOTE ]
RussH said:
I'd expect about 1.5 amps DD with a 3.4v Vf on alkaline batteries. A 1 ohm, 1 watt resistor would get you down to about 1 amp. Better would be a Shottky diode, which would add about a .3v drop, effectively giving you a 'k' Vf with very little loss. A 2 watt Shottky is smaller than a 1/2 watt resistor. DD on alkalines wouldn't be too bad, tho, since they would drop to about 1 amp after maybe 1/2 hour of use. HTH, -RussH
[/ QUOTE ]
Actually, for a Luxeon and 3 alkaline cells, resistive current limiting gives a flatter discharge curve than the use of a diode. A diode gives an almost constant drop across it while the drop across a resistor decreases as the current decreases.