Lifespan of overdriven Sony diode?

I started a thread over at <alt.laser> (http://groups.google.com/group/alt.lasers/browse_frm/thread/06f949f44b83dce1#1588dec47ef5e121)
on my latest brick laser.

Someone over there jumped all over me claiming that at the levels we're driving these diodes (250-300mA) they will have a very short lifespan. My response was 'who cares, it's a $20.00 diode and even if it only lasts 10 hours that's a lot for a pointer'.

Still it would be nice to have an idea how long these diodes last when driven over spec. Someone with a LPM needs to take a well heatsinked diode and drive it like a pointer (say 1 minute on, 1 minute off) until it fails at different current levels - say from 180mA thru 300mA in 20mA increments.

Anyone have anecdotal stories on how long these things last?

Driving a diode at 250 mA will have a long life as long as you mount a heatsink on the module, or use it without a heatsink and give it short duty cycles. If you drive it at 300 mA, you might be able to get 200 mW out of it, but the it's life will be shortened a lot, even with a heatsink.

You might get 3 months if your lucky out of an overdriven diode with proper duty times and heatsinking.

spyrorocks said:

You might get 3 months if your lucky out of an overdriven diode with proper duty times and heatsinking.

Click to expand...

But this doesn't really mean anything because it depends on how much time it is used during the three months. Also every diode has a bit of a different personality, some will last longer than others. There are too many variables involved too...like which driver is one using. It would be really difficult to do time tests.. ;D However I do agree with flogged...for $20.00 who cares, and I will leave it at that..lol.

Thats right... all I have been hearing is its lasted for 3 months being overdriven...

just imagine how many you would have to burn up to get any kind of average, and that would have to be done at all sorts of mA and duty cycles for a range of diffrent diodes- after all, what good are measurements if you cant compare them?

im thinking $ x time (and time = $)

$ X time when time = money? is the answer 0? well good luck finding diodes for no money!

ehhh... not exactly there MW1111.... if you let time=$. then you would have $ x $ which comes out to ($)^2. so you would have money squared.

Unfortunately theres no way to tell. You'll find plenty of anecdotal stories. People will tell you that 250mA is perfectly okay. Others will complain that their diode died after a few hours at 200mA. It really is a complete toss up, every diode is different. You may get a lovely 10,000 hour life from one, and instant death from the other. If someone tries giving you a concrete answer, they're lying

i know i had a diode that died within a week running at 250ma with a nice tantalum cap and everything, i guess it really does depend on luck.

...lazer... ;D ;D ;D