Premature LED failures?

Nubo

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Dec 23, 2004
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One of the most attractive features of LED is, of course, not having to worry so much about "blown bulbs". But I've been having problems with an LED light lately. I'm not going to name the manufacturer since they're bending over backwards to make it right. But, so far, I've had a 75% failure rate in just a matter of a few hours of runtime. These are 5mm LEDs, and aren't driven overly hard as far as I can tell. The Mfr. has a good reputation. The light itself wasn't abused.

The failures have all manifested initially by a "flicker" which progresses to a flashing/strobing behavior. The output didn't dim, just became intermittent. In one case the lamp stopped lighting altogether.

I guess I'm curious as to what exactly could be failing in these lamps? Could it be the thin wires leading to the die? Damage during soldering? I don't think the phosphor failed.

It's kind of disheartening as it has blown my assumptions about the reliability of LEDs.
 

Tremendo

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Dec 31, 2005
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Nubo said:
It's kind of disheartening as it has blown my assumptions about the reliability of LEDs.
I'm pretty new, but I'd say in general, LED's are fine. You're just getting some bad luck or maybe you keep trying the same light and there's a problem. :thinking:
 

IsaacHayes

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It could be a problem with the electronics too or assmebly of the light. The LED may well be fine. LED flashlights are more than just a "bulb" usualy. They usualy have electronics along with the LED.

I remember Arc had a problem with a batch of IC's they recieved and ended up the lights would flicker...
 

DCFluX

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Jan 4, 2006
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I've noticed several random failures of LEDs made by some of the cheaper companies from China.

Depends on who made it as to whether it will short or open.
 

Nubo

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Dec 23, 2004
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IsaacHayes said:
It could be a problem with the electronics too or assmebly of the light. The LED may well be fine. LED flashlights are more than just a "bulb" usualy. They usualy have electronics along with the LED.

I remember Arc had a problem with a batch of IC's they recieved and ended up the lights would flicker...

The unit was repaired once (not replaced) and indicated "replaced defective LEDs". 2 had failed at that time. Now, one of the original LEDs has gone out the same way. The 2 replacements seem ok. I don't know whether to blame the LEDs or the light at this point so asked for a complete replacement which they are willing to do. I'm just sort of curious as to how often folks have run into flaky LEDs.

In answer to evan9162 - I'm just going by the light output and runtime.
 

greenLED

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Mar 26, 2004
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Knowing which light you're talking about would help us diagnose the problem.

The fact the vendor is fixing/replacing the lights is a good thing - LED circuits are not failproof.
 
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