LED destructive testing

Has anybody done any destructive testing? Like sticking LEDs on fan-cooled heatsinks and slowly turning up the current until they pop?

w

We all do destructive testing, but we don't usually mean to !!!

they dont pop, they just change tint and goes out..

only time it went was... well, this was intentional....sticking a 5mm red into a switched AC receptacle and click on... BAM!

most destructive testing is based on overdriving experimentation on the table, AC will burn down houses

Illum_the_nation said:

they dont pop, they just change tint and goes out..

only time it went was... well, this was intentional....sticking a 5mm red into a switched AC receptacle and click on... BAM!

Click to expand...

Behold the NED... Noise Emitting Diode! Only works once though. :laughing:

POPPING 5mm's on the ole "line"
fun times, fun times!!.. can get 20 "NEDs" (good one PhotonWrangler!) down at the shack for bout $2. More fun than a $3 bureeto!

last week I was running a Luxeon K2 in direct drive 3.6 v I had put some artic silver compound on the led and placed it on a heatsink. after while I heard a boom (something falling on the ground). 3-4 minutes later I saw some smoke and noticed that the heatsink had dropped. I rapidly disconnected the batteries. (The Luxeon is still working OK though)
Nice to know they can take a beating.

I took some strange looking bulbs from my garage and put 120 votls through them (no obvious filament) purple flash then just a crack and you have a sealed glass bulb with shattered metal and glass inside.

been there, done that

Some time ago, I used a bank of 12 AA nimhs connected in series to power some circuit. Then I decided to use the same bank to DD a lux3, taking power only from the first two cells, so I had 3 output wires coming out of the bank. Just guess who connected the lux3 to the wrong wires so that it got DD'ed from 10 fully charged AA nimhs... I can tell you that for 3 nanoseconds it was the brightest luxeon ever, anywhere! Later I tested the nimh bank with my DMM and came to the conclusion that for a very short moment the luxeon was getting 12 amps to it... :green:

-N

I accidentally hooked a cheap 5mm red LED up to a 12v power supply once. It popped big time, and I got hit with LED fragments.

popping leds is anything but fun....my AC testing shot the head from one wall to the other...sounded like BBs...didnt get hit by it though, dunno how that would've felt.

Im surprised I didnt blow the fuse

I once ran about 3.5A through a Luxeon batwing on a heatsink. It was bright, angry blue for about 20-30 seconds then it got dim very quickly and wouldn't light up afterwards. That was on purpose too.

we have yet to see liquid nitrogen cooled emitters being overdriven

when was this? :wow: :goodjob: evan9162

Gnufsh said:

I accidentally hooked a cheap 5mm red LED up to a 12v power supply once. It popped big time, and I got hit with LED fragments.

Click to expand...

Many years ago, on my first technician job, a co-worker and I got bored and started connecting 5mm LED's to a variable supply; cranking up the voltage until they went "BANG!". Fragments bouncing off the walls. We had a part-time kid in the next room, counting parts. Never could get him to wear his ESD strap. He heard the bang and the fragments bouncing around, came running to our bench, and I told him "John picked up an IC without his strap on." Kid always wore that ESD strap after that.

OK,thanks. So no, nothing extensive, no comparisons, no identical conditions, no records.

Thanks evans9162...

w

nocturnicu great story.

Cree® XLamp® LED Reliability
"Light source failures can be divided into two categories, catastrophic and parametric."

Nocturnicus said:

Many years ago, on my first technician job, a co-worker and I got bored and started connecting 5mm LED's to a variable supply; cranking up the voltage until they went "BANG!". Fragments bouncing off the walls. We had a part-time kid in the next room, counting parts. Never could get him to wear his ESD strap. He heard the bang and the fragments bouncing around, came running to our bench, and I told him "John picked up an IC without his strap on." Kid always wore that ESD strap after that.

Click to expand...

LOL, good story!
That being said, I'm going to go pop more leds, c-ya
I have a basic power supply...1.5-15V @+/- 1 amp...doesnt seem to pop leds too well, but it does when it wants to.

anybody know at what voltage of current does catastrophic failure occur?
temperature---->|
. the red line