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Greg's diodes... :P

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Hey-
I just burnt through 2 of SenKat's GB diodes today, and I'm 99% certain that it wasn't by getting it to hot... Are there other ways to kill these that I'm not aware of? (I'm sorry about the noobish question... DIY's aren't anywhere near my most knowledgeable subject. :-[ )
 

Hemlock_Mike

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What was your measured LD current ?? That may be the clue. Did you have a capacitor across the LD ??

Mike
 
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*Smacks himself repeatedly for not thinking of that*
D'OH!! I can't believe it! After years of doing this... :-[
~60-70 mA @ 3V. (I can't get a steady reading from my stupid multimeter :mad: )
 

Hemlock_Mike

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Those readings seem wrong somehow. 3 volts should push the LD to well over 70 mA.
70 mA is just above the lasing threshold as I recall. I'm missing something here.

Mike
 

Things

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is it shorting out in any way? Could you post some pics or something? 70ma is pretty low, but my DIY red was running on 120ma @ 2.5V nd it could burn well, so i think its over the lasing threshold a fair bit?
 

Kenom

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ONE of the easiest ways to kill these diodes other than driving them with too much current (over 350ma) is to when connecting power short the two pins together. (instant death) I don't know how many times I've hit the positive connection to both the negative and positive and turned a diode into a LED.
 

a_pyro_is

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Kenom said:
ONE of the easiest ways to kill these diodes other than driving them with too much current (over 350ma) is to when connecting power short the two pins together. (instant death) I don't know how many times I've hit the positive connection to both the negative and positive and turned a diode into a LED.
??? :-?
I don't understand how that would kill a diode. Unless it simply confused your driver which then floated at the supply voltage and the + pin was reconnected.

mr_munchies said:
Hey-
I just burnt through 2 of SenKat's GB diodes today, and I'm 99% certain that it wasn't by getting it to hot... Are there other ways to kill these that I'm not aware of? (I'm sorry about the noobish question... DIY's aren't anywhere near my most knowledgeable subject. :-[ )
There are many ways to kill a laser diode, but I'm not sure you've killd this one. How about you start from the top.
What are you using to drive the LD?
When you first pulled the diode out from the Al foil you...?
Post some pics of your driver as well as of the LD.
Maybe we can get you giong with this one.
 
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Mike-
Yeah... They didn't seem right to me either. I don't know what the deal is :-/
Kenom-
That might be it...
Things-
What do you want pictures of?
 

JECS

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i thought i had killed a diode earlier today.. then i thought..maybe it has something to do with this resistor i stuck in the circuit (not paying attention to the driver schematic i put in a 100ohm resistor rather than 10). even after replacing it with a 19 or some odd ohm valued resistor in its place it still looked like the first diode i popped. i switched to 3AAA rather than 2AA and that fixed my problem. you can run these things off 2aa for testing etc. just dont do it long. i use at least a diode and capacitor when i do this (now)(ran it for about 10 minutes). be as safe as you want. i bought 5 so im checking my possibilities.. in my case a resistor was to blame though. as soon as i got rid of it or upped my power it was fine. just dont overdo it
 

Things

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i think some pics of the driver/diodes output would help clarify a little bit. If the output is dim, and the diode heats up fast, its most likely dead, if it doesn't do anything, you either broke the internal conections in the diode somehow, or your driver is not right.
 

Kenom

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a_pyro_is said:
[quote author=Kenom link=1196123185/0#5 date=1196176268]ONE of the easiest ways to kill these diodes other than driving them with too much current (over 350ma) is to when connecting power short the two pins together. (instant death)  I don't know how many times I've hit the positive connection to both the negative and positive and turned a diode into a LED.
??? :-?
I don't understand how that would kill a diode. Unless it simply confused your driver which then floated at the supply voltage and the + pin was reconnected.
[/quote]

I couldn't begin to imagine what's going on with how that kills the diode. I've got a battery pack of 2 AAA's (weak ones) that I use for testing the diodes. I will put the positive on the positive and the negative on the negative and while pulling them apart will hit teh negative with the positive while still connected to the positive. INSTANT DEATH. I've done it probably 10 times now. I just got a laser back that was shorted while running hte pins having migrated together and shorted to each other while running. again INSTANT DEATH. I'm going to start using a board in between the pins to prevent shorting.
 

a_pyro_is

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I hope someone with more understanding on this will chime in. But either way, thanks for the warning Kenom.
 




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