Blown LED - but why?

[Novastar]

Neo... thanks for confirming that about the Max. Cont. Current thing... I was beginning to wonder about what Eandori was doing regarding over-driving a Lux V to 1000ma (instead of 700ma).

He says it is working fine, and he sees a distinct brightness difference, but... I wonder when or if the thing is going to start losing its brightness... and/or simply blow!

For a Lux III or K2... big deal, $6 to $8 gamble. For a Lux V... I don't know if it's worth $24 every time one would blow.

SO... the quote of the day is:
~~ Give your LED what it WANTS... no more, and preferably a bit less... ~~

[neophyl]

It depends on what he is doing when it comes to overdriving. In certain circumstances you can drive an led alot. For example using a pulsed source the led is only on for a very short space of time. Ive pulsed normal 5mm IR leds that have a 100ma max current at 1500ma before but only because the led was being driven for a fraction of a second with a 12% duty cycle, so they can cool down between shots (it was for a outdoor lasertag system)

In simple terms the death of any led is heat. Heat is caused by the flow of current. With Jonitus's example he could see the thin wire was broken. This is what happens with a fuse, too much current for too long heats up the wires and they pop. Thats good for a fuse, not so good for an led
Alot of power for a very short duration and things dont get hot enough damage it. Thats why pulsed operation works but the figures can look misleading to someone who doesnt follow exactly whats happening.

With our use for sabres a puck/driver of the proper current rating is best, and if you have to use a resistor and cant find the exact resistor value you want use the next value UP, not below.

[Novastar]

Oops, I forgot... good point! Eandori is using CF, so... that's right, as long as he doesn't keep it on the "solid blade" mode for too long (or just always uses the flickerdepth modes alot), gotcha... should be good. Thanks again...