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Identifying an unknown 515nm diode

3zuli

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This is my first post here after a very long time. I recently bought what was supposed to be an Osram PLT5-520 diode from techhood https://www.ebay.com/itm/OSRAM-PLT5-520-50mW-Green-Laser-Diode-TO18-5-6mm-New/143292564817. I used this driver set to about 100mA https://www.ebay.com/itm/405nm-Laser-Diode-Driver-for-20mW-200mW-3V-5-5V-CC-Circuit/261146369662.
However, when I hooked it up using the pinout from the PLT5-520 datasheet, it did not work and it behaved as an open circuit. Thinking that I must have fried it, I ordered a second diode, but it had the same problem. Then I found this feedback comment for the listing:
LDs arn't PLT5. True 515 nm. Without PD. Pin3 - LD Cathode, Pin1 - LD Anode.
And indeed, the diode works with this pinout. I also used a diffraction grating and a reference 532nm laser to determine the wavelength, and it seems to be spot on at 515nm. Given the pinout and wavelength, can someone help me identify this diode?
 

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paul1598419

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Is this really a case positive diode? If so, it might be a Sharp diode. Are there any numbers on the diode itself, especially around the window?
 

3zuli

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It appears to be case-neutral. There's a "76 Y0" marking on the side of the can.
 

paul1598419

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Pin 2 is your case pin. Looks pretty case positive to me. That number means nothing to me. If you look under magnification around the diode's window you may see some letters and numbers there.
 

3zuli

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That pinout diagram I posted might be misleading you. That is for PLT5-520, which is indeed case positive. My diode has anode on pin 1 and cathode on pin 3. Inside I can see bond wires connecting the LD die to pins 1 and 3. As far as I can tell, the case is neutral. And there are no more markings on the diode.
Is there any compiled list of available 515nm diodes that I could compare this against?

Edit: I found this thread https://laserpointerforums.com/threads/sharp-515nm-laser-diode-gh05130b2g.103461/ with the Sharp GH05130B2G diode, which seems to be the closest match so far. The only small difference is that the datasheet says the can marking should have a "Z" in it, but mine has an "Y".
 
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paul1598419

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It could be that diode. A "Z' or "Y" wouldn't be a determining factor as these are often just iterations and change from batch to batch. look for an SB32xxxx number printed around the the diode's window on the can. That should be there if it is the Sharp.
 




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