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3 in a row GONE!!

o_DEATH_ANG3L_o

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Man I am so mad. :mad: I had three DVD burners. Two of them were Liteons 20X and one was a phillips 16X. All three were OPEN CAN diodes. I just dont get it though. :-? I was VERY precautious in removing these diodes. I understand they are WAY more sensative than closed can. But here's the thing. I wore a grounding wrist strap. Worked on an antistatic mat. Grounded my soldering iron and only touched the diode to the solder for a half second to 1 second. I hooked it up starting at 80mA and it was decently bright. But then as I went up, nothing happened. I went to 280 mA and it barely got brighter. I was like what the heck??? This diode will refuse to lase. I just dont understand. Unless the diode was already blown into an LED BEFORE i hooked it to power. But rest assure, I was EXTREMELY cautious when removing the diode and never had heat on the leads for more that 1 second. Well that is 3 in a row that are refusing to lase or perhaps blown. If anyone has any ideas what might of happened, please let me know and share your experiences with open can diodes. Thank You.

Ok this picture is at 200 mA. It looks bright doesn't it?? Yeah well looks are deceiving :mad:. It stayed this bright all the way to 280 mA?????
 



Rhith

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Tis a shame mate. Try putting it in a module maybe and seeing what kind of power you can get out of it though. As you even said, looks can be deceiving!
 

Gazoo

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Well it happens...but I am very surprised the Phillips 16X had an open can in it.

I don't know what went wrong, but continued breadboarding can be very dangerous if your connections are not good. Also did you have power turned off, and discharge the cap before you plugged the diode into the breadboard?
 

o_DEATH_ANG3L_o

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Gazoo said:
Well it happens...but I am very surprised the Phillips 16X had an open can in it.

I don't know what went wrong, but continued breadboarding can be very dangerous if your connections are not good. Also did you have power turned off, and discharge the cap before you plugged the diode into the breadboard?
I had absolutely no power stored in the capacitor prior to hooking the LD up. I made sure to discharge the capacitor before applying power. But wow 3 in a row!!! Just dont understand it all. Here is what the LD looks like. All three looked like the one in the photo below.
 

Gazoo

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I don't know...the only other thing I can think of is maybe your power supply is causing a spike when you turn it on.

But I would do away with the breadboard and get a PC board at RS. This will at least eliminate whet could be one of the causes.
 

yes8s

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Dude I feel you pain... Same thing happened to me a couple of days ago...

I've come to the conclusion that the open cans are cursed :)

I really did not expect them to be soooo sensitive to everything... They're like women ;D

Mine would not draw more than 100 - 150mA even though I set daedels circuits to supply 150+ mA. I think the internal resistance goes up the more damage you do to them because by the end of playin around with it and tryin to get it to work, the voltage drop accross it had jumped to 4.5V with small supply current.

I got pissed :mad: off and I cut the diode in half errrr.
 

Things

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LD murderer!!! :mad:


;D
but ya, i have no idea as to why 3 would die?????????
 

o_DEATH_ANG3L_o

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Well I just do not understand it at all. 3 freaking diodes in a row. I wish I knew the answers. :'( :'(
 

Kenom

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yur scarin me. I've got a brand new DVD-rw showin up tomorrow and it's the infamous pioneer dvr-112d. I'm kinda scared now. I've sucessfully harvested dozens of closed can diodes from dvd burners up to this point and not killed on single diode from that. Now I'm gonna have to be ultra careful.
 

Gazoo

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I don't know especially, since that one in the picture wasn't removed from the heatsink. That one should have worked.

The diode in the last LiteOn I harvested worked until I removed it from the heatsink, and I was super careful. It looks perfect from all angles but will not give off any light. :'(

My most recent harvest from a Pioneer 112D was successful.

Anyway, since we are close to getting news on the Phaser Diodes, I would wait on that and not try to harvest any more diodes. Hopefully the Phaser Diodes will be just as powerful as the open can diodes. So far it is looking good.
 

Gazoo

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Kenom said:
yur scarin me. I've got a brand new DVD-rw showin up tomorrow and it's the infamous pioneer dvr-112d. I'm kinda scared now. I've sucessfully harvested dozens of closed can diodes from dvd burners up to this point and not killed on single diode from that. Now I'm gonna have to be ultra careful.
One small note is according to VaThink the positive leg can be easily moved resulting in detachment of very fine wire inside of the diode. But I don't know...just be super careful.. ;D
 

zerafiel

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What does the beam look like? Do you see black strips, various beam artifacts etc? all this can point to catastrophical optical degradation of the end facets caused by transients, esd etc. How did you measure current? did you hook up your dmm in series or measured it through a sense resistor? Hooking it up in series might alter the circuit dynamics.

Your cap looks pretty far away from your ld on the bread board. if you accidently disconnected the ld and reconnected it, it might blow the diode. unstable connections from the bread board might do that too.

I'd follow daedal's advice and solder the cap directly onto the LD before playing with it. Then the ld is pretty much static proof (and cap proof) after that. Shorting the diode before actually working it might help too.

I've never worked with an open can before so I can't say how sensitive those are. But I feel your pain man. 3 in a row! And the problem is still undiagnosed... :(
 

MrBurns

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I can also attest to the fragility of the open can diodes, as I've lost both that I've worked with... I think they are difficult enough to question whether they're worth the trouble...

I ordered 5 GB diodes though so I will just be patient and wait for those :)
 

o_DEATH_ANG3L_o

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Yeah thanks guys. I now know that harvesting open cans is not worth it. As far as the breadboard goes, I made sure everything is connected well. In fact I have used this EXACT setup in testing my other closed can diodes with no problem at all. Thats why I am frustrated to no ends because I really do not know why this is happening. The pins on this LD looks like this:

* <------GROUND (I know this because it is attached to the can itself)
* *<-----Not sure prolly photo or something but it didnt work when hooked to (+)
^
|
|
I think positive because when I hook it up to (+) it lights up.

Aside from all this I really can't understand this mishap. I mean 3 in a row like that. I just don't get it at all. :-? Kenom I saw you mention something about being REALLY careful. Well I was as careful as any would be. Grounding wrist strap, grounded soldering iron, anti static work mat, and held the heat on the LD pins no longer than 1 second. Aside from that I am only using a 25 watt iron. All I can say is I worked with a few closed cans and had no problem at all. The open can is EVIL. I can personally say that I am staying away from them from now on. Kenom, good luck bud. ;)
 

Robk

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I learned the hard way to use batteries to test / power up laser diodes. Even a good lab-grade power supply can output spikes when turned on, and if the voltage or current adjustment pots in the supply are old or dirty, they can create all sorts of spikes that will kill diodes. The only diodes I will connect to a power supply are the ones that I build a 317 current regulator with associated caps and other protective devices already in place, as a module connected to the diode. I now use 4 AA's or 2 CR123's - too many blown diodes from a decent "stable" AC powered power supply.

Were you using an AC powered power supply with variable current and voltage settings?

Rob
 

o_DEATH_ANG3L_o

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Hey Rob my PSU did not have settings on it. I am also using Daedal's circuit to power the LD. So no spikes could have occurred.
 







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