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Can anyone help me identify this diode?

Scottyzedinosaur

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Hey guys, I had a computer to screw around with, so i decided to "recycle it" into a laser. My only problem is I cannot identify the diode...so I can't find the pinout or current to run it at. It has a really short can though...I got it from a DVD/CD ROM RW. And there were two diodes; one in a heatsink, and one pressed into the sled itself...impossible to extract. So I grabbed the one in the heatsink. Can anyone help me identify it?
p.s. Click on the picture for full size.


 



Eudaimonium

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Heh, nice pictures. If only other people wanted to put up good pictures with their "help/identify this/that" threads instead of blurry out of focus sacks of pixels which hurt my head.

By the looks of it, it's most likely IR diode.

For indesputable confirmation, look at the diode's window so that it reflects light from your bulb/window (white[ish] light source).

If the reflection you get is in greenish tint, it's IR diode. If it's blue tint, it's red diode.
 

Scottyzedinosaur

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Well, either I broke the window extracting it, or it doesnt have a window...I used my flashlight to check inside, and I didn't see any broken glass fragments...just the little wires connected to the die.
 

Eudaimonium

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In that case, it's definetly Infrared.

IR/Red combos in PHR sleds also do not have windows.

Your diode did not have a window to start with, I've seen those. Nothing to worry about.

Don't ram more than 270mA into it and you're fine :)
 

Scottyzedinosaur

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Thanks alot:) you have been quite helpful=p I would rep you, but I did that a couple days ago^^
 

phoenix77

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+ REPZ for my pal & his great assistance to a relative newcomer to our Forum. Nice going pal............. rob
 

hydrogenman15

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I think there is another thing you can do to find out if it's a red or IR diode. If you have a multimeter you could measure the polarity by hooking it up like this:

* (+)

.......* (-)

*

If it doesn't read zero ohm's then it's probably not an red diode. There is a thread here showing the polarity of several different types of diodes here -->http://laserpointerforums.com/f51/diodes-compilation-all-diodes-data-one-thread-45042.html hope this helps

--Hydro15
 

Eudaimonium

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+ REPZ for my pal & his great assistance to a relative newcomer to our Forum. Nice going pal............. rob
Thanks a lot, your and Chipdouglas's rep sure boosted mine a lot! :)
I think there is another thing you can do to find out if it's a red or IR diode. If you have a multimeter you could measure the polarity by hooking it up like this:

If it doesn't read zero ohm's then it's probably not an red diode. There is a thread here showing the polarity of several different types of diodes here -->http://laserpointerforums.com/f51/diodes-compilation-all-diodes-data-one-thread-45042.html hope this helps

--Hydro15
No, wrong.

You should NEVER measure laser diode with multimeter, for anything.
Reason is that multimeters are not accurate sources of current and there exists small possibility that you will destroy your laser diode, either by static or measurement itself.

Diodes can be easily told apart by their physical differences.

Red diode will also never read zero ohm. Depends on your DMM and measuring range, it will always give different readouts. Most accurate would be to switch to Diode measuring mode in which your red diode should read around 2.7-2.9 V of drop voltage, however that's falling into category described above - unnecesary risk of destroying your diode.

The only reason you should measure your diode if you suspect it went OC, then you switch to high ohm measuring range. If your DMM does not read anything, then it's OC ( Open circuit). If it does read something, then your driver or something else in your setup is wrong.

OC-ed diodes do not give out any light at all, as opposed to LEDed diodes which give faint LED-alike emission.
 

anselm

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Eud said:
You should NEVER measure laser diode with multimeter, for anything.
Reason is that multimeters are not accurate sources of current and there exists small possibility that you will destroy your laser diode, either by static or measurement itself.
How many diodes have you killed that way?
Just wondering, because I have done this many times, although only with 4 or 5 diodes.
But still several times each one, and none died.
The current in diode measuring mode is so small, I cannot possibly imagine how it could blow
a diode. I see the risk with ESD, but that can happen anytime, doesn't depend on the DMM.

I don't know, I find it so practical to determine a diode's color and pin's polarity, that I do
it all the time and never even worry about it. Guess I'm one lucky guy.
 
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Eudaimonium

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How many diodes have you killed that way?
Just wondering, because I have done this many times, although only with 4 or 5 diodes.
But still several times each one, and none died.
The current in diode measuring mode is so small, I cannot possibly imagine how it could blow
a diode. I see the risk with ESD, but that can happen anytime, doesn't depend on the DMM.

I don't know, I find it so practical to determine a diode's color and pin's polarity, that I do
it all the time and never even worry about it. Guess I'm one lucky guy.
It never hurts to be on the safe side. Simply looking at the diode tells you enough, and storing your diodes in labeled boxes is more than enough.

I would not go measuring diodes around with DMM. Hence, I didn't kill any, because I haven't measured any (except to confirm death :p )
 




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