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max safe working current?

Lasieur

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I saw a series of photos where the experimenter was using a variable power supply and lpm on a diode. He was ramping up the current on the diode while measuring the mW output. After several increases in current the power of the diode leveled off. in fact the mW started dropping on further increases in ma.

Is it safe to run the diode at this level point or is it better to back down a little before final assembly? Is there any rule of thumb for determining the max safe working current on a diode with no specs?
 

jimdt7

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Well, there isn't a correct answer to your question...every diode is different in many ways, not to mention exact same diodes not being the same. (For example we have seen the 9mm N!ch!@ diodes run @2A with ~3W output and others set again @2A but with only 2.5W output). Some diodes can handle the extra current by dimming but others simply die...if you want to power an unknown diode I think 100mA is a good start! :beer:

Have a nice day,
Jim
 
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On such diodes, the safe current is a bit below where the dimming starts. If you power it at the level just
before it begins to dim, it won't last too long. Turn it on and off a few times and startup transients will kill
it. By the time it starts to dim, the OEM's specifications have been far exceeded, so this is no good as a
way to find factory specs on an unknown diode. The max safe current on a diode in a handheld is only
known after many hours of runtime.
 




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