laser burnout problems

[lasernoob117]

Can anyone tell me why my diodes keep burning out?

I've harvested three or four diodes from old dvd drives that I've purchased online and tried running them using a 3.7 li-ion battery and an amc7135 with no success.

Is my battery voltage too high or am I running my diodes over current? I've read that too low a voltage can be a problem too!?

any help would be awesome as I don't want to waste any more diodes or time repeating the same mistakes.

Cheers, J

 

[WizardG]

What are you using for a heat sink?

 

[lasernoob117]

the diodes were mounted in a small metal lens assembly, which seems like it would be a pretty effective heat sink, however the diodes have been burning out either the instant power is turned on or within the first few seconds of being turned on. I attribute the variance to the fact that whilst they are all dvd laser diodes they are not the exact same model, each coming from different manufacturers.

 

[Unown (WILD)]

Could be ESD that's killing them

 

[WizardG]

the diodes were mounted in a small metal lens assembly, which seems like it would be a pretty effective heat sink, however the diodes have been burning out either the instant power is turned on or within the first few seconds of being turned on. I attribute the variance to the fact that whilst they are all dvd laser diodes they are not the exact same model, each coming from different manufacturers.

That just sounds like too much current. Too low a voltage won't damage the diodes. Try an LM317 driver with an adjustment pot and turn it up slowly. And build a test load for dialing in your driver. Search this forum if you want instructions on that.