Humm!
I don't have SC, what voltage are they asking for and what lumens are they?
What temp range is the 'white' light at?
Has anyone got the latest Silicon Chip and ordered some of the LED's out of it?
They look very bright. Also any other ideas about driving them instead of using the LED Dazzler circuit?
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Humm!
I don't have SC, what voltage are they asking for and what lumens are they?
What temp range is the 'white' light at?
Same LED's I found on DE.
3.6V at 2.8A according to the article. 900 lumens.
Not sure about the temp range either.
sorry for the noob question but can these be driven straight from power source or do they defiantly require a driver????
Isuzu MU
nvm... found what i was after -
should be good to use in the old torches i've been collecting for led conversions. now looking for battery packs
Isuzu MU
To get the rated max output from leds they need to be run right on their max rating, on the ragged edge so to speak. Go even slightly over that edge and you risk very early failure so regulation of the power supply is necessary. Also, they typically need to be pulse driven with a very specific duty cycle to get the most out of them so seemingly over-complex power supplies are absolutely necessary if you don't want to make your very own DED (dark emitting diode) sooner than expected.
kcsoft (06-02-11)
They need a constant current source, regulated at 3.6V too. Usually this is done via a resistor, however due to these being 10W per Led, and 2.8A drawn.... The resistor will get very hot, very quickly. The driver is just basically a PWM circuit I presume, don't quote me on that, haven't read the actual circuit description yet.
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kcsoft (06-02-11)
Using a simple series resistor to reduce LED voltage negates the efficiency advantages of the LED especially in the case of high power LEDs where you could easily be dissipating more (of the energy you're trying to conserve) in the resistor than in the LED itself. It also means you need to design it so that the worst case highest input voltage will not result in a LED voltage exceeding its rating which makes the typical average input voltage operate the LED somewhat below its capability which defeats the purpose of using the high power device in the first place as it could end up running at 1/2 power or less 99% of the time to guarantee long life.
I've got a 3W LED downlight with integrated electronics to run off a 12V AC supply which puts out quite a lot of light and the entire housing of it is a diecast alloy heatsink. It's a bit disconcerting how warm that heatsink gets after a short while which, to me, indicates there's a long way to go before we get these things really as efficient as they could be.
Don Benosee (06-02-11)
I've looked at these high powered LED's (M16's etc), for a while.
I actually have 12v runs through the house running 12v LED's and 12v lights straight.
But IMO, by the time you buy these LED 'emitters', buy the cable, buy the switches, buy the heat sinks, buy the P/S, it's a lot of money.
Correct me if i am wrong here;
About $35 per light.
Electricity is 22c per 1000 watts. That's 159,000 watts - per light.
Running a 10W Energy saver 240v (output say 80Watts),
That's about 662 days (24/7), of non stop usage.
If i'm correct, that's why i can't be bothered to go down this path.
Got those LED's for a special price of $16 at the moment:
The DealExtreme ones seem to be a little different.
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What makes you think I'm going to use these for home use GT250? Experimental purposes. Maybe mount inside a compact torch, or bicycle etc.... depending on how bright they are. Don't want them to be too bright for other road users.
You can't save money with these for home use that's for sure.\\
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