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FrozenGate by Avery

Burnt Diode?

Bristol

Bristol

0
Joined
Oct 18, 2012
Messages
57
Points
8
First off, I have been researching this, but nothing on the threads look like my scenario. I bought a Survival Lasers host kit. I followed the tutorial (this being my first laser build) and did every step.

Details: I ordered a 2 (ish) watt diode and sent a special request to Gary (head of Survival Lasers) to put a nice driver in. So, I soldered the connections, making sure not to overheat the diode. Put the Aixiz module lens in and turned it on. It did a really bring flash of blue (the diode is blue) and then went dim. The beam itself is way to big, being 3 inches at about 2-3 feet. What is going on here? Also, the heatsink gets way too hot.
 





Not too much of details there.

Like with any troubleshooting, you don't ask a doctor what's wrong with you over telephone,

I'd need to ask you to snap a few pictures of your setup so we can see what are we dealing with here.
 
It sounds like something went wrong with the driver or some of the soldering. By your description of the way the diode acted is it sounds like it was damaged and it is LEDd. The diode or driver may have some ESD damage. Did you remember to ground yourself before touching the diode and driver? Also, did you remember to short out the driver before connecting it up to the diode?

I have to agree that some pictures might help us help you.

If you can't figure out how to post an image just paste a link to it.
 
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ApexProxy said:
It sounds like something went wrong with the driver or some of the soldering. By your description of the way the diode acted is it sounds like it was damaged and it is LEDd. The diode or driver may have some ESD damage. Did you remember to ground yourself before touching the diode and driver? Also, did you remember to short out the driver before connecting it up to the diode?
Click to expand...

It's my first build, I was always grounded, and I tried not to touch the diode itself very much. But no, I did not short out the driver. The driver is in a container itself, called the "pill"? Anything I can do about this? :scowl:
 
7344-photo-2012-10-29-15-17
 
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Doesn't tell us terribly much,

But so far, I can see that (maybe) you have not isolated diode's pins. It's possible that they bent and touched while the laser was powered, judging from the twisted pair wires.

Diode's pins must NEVER touch, otherwise you lose driver, and sometimes diode too.
 
Eudaimonium said:
Doesn't tell us terribly much,

But so far, I can see that (maybe) you have not isolated diode's pins. It's possible that they bent and touched while the laser was powered, judging from the twisted pair wires.

Diode's pins must NEVER touch, otherwise you lose driver, and sometimes diode too.
Click to expand...

As soon as I was done soldering it, I put electrical tape between the two main pins, I left the red separator on at the bottom.
 
I'm still thinking the diode was killed by ESD or a capacitor discharge spike.
 
So... orderer another diode? If I do, what do I do to prevent this from happening?
 
Before connecting laser diode, briefly touch the driver's output wires together while the driver is unpowered. (NOT while powered, obviously).

Reason behind is that, if your driver ever ran without a load, the output capacitor which is directly parallel to the diode is retaining a lot of charge. The moment you connect a diode to it, that charge is gonna shoot right through it and kill it.

Briefly shorting the output is obviously emptying the capacitor so it's safe to connect your laser diode.

Observe proper ESD safety too, I know you said you did ground yourself and all, and personally I never had a single ESD incident in my life (except ones caused intentionally, usually zapping other people with finger tips. Fun.), but better safe than sorry.

Also, one of most important steps is, no matter what instructions you provided to the seller, is to test-load the driver's output. Which means, constructing a dummy load and using it to measure out how much current is the driver actually giving out.

It may be too much for diode to handle. That's what I suspect the most in this scenario, you did say the diode lit up incredibly brightly for brief moment before going LED.

Care to describe exactly what happened? We may confirm the culprit here.
 
Ohh... that makes a lot more sense. Okay, every time I turn the laser on, it get's really bright (I don't have the lens on right now, because when I put it on it doesn't focus the beam at all, it's still a huge dot) for about.. 2 seconds, maybe 6 if I leave it off for a long time, then dims super low.
 
So wait, it starts out bright EVERY time you turn it on?

Well that's a bit of an important detail to not mention until now, because it means your diode is NOT dead.

It means your batteries are.
 
Hmm, well the issue with it spiking up and then dimming every time you use it sounds like driver damage to me. The issue with the focus sounds like you either have the lens backwards or the lens is really dirty lol. If you had an alternate way to power the diode you could test it alone to narrow down your possible problems.
 
Nope. It's batteries.

Trust me on this one.

Charge the batteries / buy new ones. Try again. Rejoyce!
 
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