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IsaacHayes said:
Ok, I understand the voltage deal now. I was thinking more along the lines of like 5w's being run at 9v is around double the current.. So 1w's can pull a lot with very little voltage changes. got it.
Re: the packaging. It seems the 3w stars are now directly on the metal star with the pcb cut around it, rather sitting on top of the copper pcb like current 1ws. So they are like a 5w in that regards. Is that the only thermal improvement? Or did they do something to the actual DIE it's self? In other words :
1w emitter same as 3w emitter?
1w star diff than 3w star in re: to mounting to the aluminum star.
In regards to the flux bins, I guess we will just have to wait until documentation is released so we can see where the range of bins starts and stops with 3Ws. Who knows how far it will overlap into 1w/5w teritory... /ubbthreads/images/graemlins/icon3.gif
One thing though, since it's getting 3x more power, shouldn't it be 3x as bright as a 1w? But if it's just an overdriven 1w then wouldn't the effeciency be less than when using 3 seperate 1w stars?
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The 5Ws run at double the voltage because of the fact that they run a 2series/2parallel configuration.
A lot of people have speculated that the die in the 1W units and 3W units is the same, and the packaging is merely different. In the case of whites, they might tweak the phosphor ratio a little bit to prevent the unit from being overly bluish.
Chances are the 3Ws are indeed less efficient. (Not sure exactly about this.)
I believe the 1W blue/green/cyan Luxeons actually use 1.25W or so. The actual input power of the "1W" units varies depending on the Vf. They're binned by Vf, color temperature, and brightness. All are rated at 350 mA. The average power is probably 1W, but it varies with Vf. (Which is why R2Hs are so desirable - Because of the low Vf, they are consuming the least power, but they're very efficient so have a high luminosity bin.)