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ArcticMyst Security by Avery

16x red LOC, what is its MAX current

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i harvested a 16x red LOC diode from a lite-on LH-18A1P. it looks EXACTLY like the diode i took out of my NEBO build wich i THOUGHT was a 20x red loc rated for 300mw. i ran it at 400Ma for a long time until just yesterday my laser shined off a mirror and back into itself instantly frying it.

so im hoping this diode is the same as my last and i can run it at 400Ma as well, but i wanted to check with the community before doing so as i cant find the specs on this diode.

i guess a good way to word my exact question would be "Whats the MAXIMUM i can run this diode at with an awsome heatsink, and a short duty cycle?"

Thank you in advance,
~Dark
 





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If your host is plastic i would turn the ma down, but if your host in metal and you are using a good heatsink, I would keep it the same.
 
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yeah its metal with a custom heatsink. wish i had the spec sheet for this diode, i wanna push it to its limits, as i have a few extra diodes on hand. im not going for longevity, but for maximum power/visibility. any idea what power level it could handle for short 20-30 seconds bursts? i want to shoot for 500Ma'ish and see what the Mw reading is.

the host is the same as in my avatar
 
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you really should be good at 400ma. I forgot what driver you are using... i remember. Oh did you ever end up making the LM317 that i reffered you too? that one is good for 1.5 amps. so if you really wanna push a LD that would be the way to go.
 
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if these are comparable to sencat's sony 16x diodes...i would limit it to 250mA.....
but thats just going by the sony 16x diode....i've no idea what yours is capable of.
 
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yeah this one is steady at 450Ma now with a heatsink on both the driver "wich is a standard LM317 like you suggested" and the diode. im happy with it there, but i want a better diode still, any suggestions on a more powerfull red diode of any sort? 5.6mm though.
 
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Is this diode a 16x or an open can? Long open can diodes are found in 18x-20x drives... or am I mistaken?
I've got an LOC from amkdeath's GB doing 300+mW after Aixiz glass sitting on my desk.
I need batteries for my multimeter so I can't check the current it's pulling :p
There was a graph of several 650/660nm laser diodes that showed power output vs. current. I don't know where it is...
But if this diode is a 16x, it will burn up at 400mA. LOC diodes can be pushed pretty hard, but 500mA is still a LOT for these.
 
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it is DEFINATELY a LOC, and i know it came from a lite-on LH-18A1P. and it came up online in more than several places as a definitive 16x burner from pioneer i do believe. my wife is sleeping or i would get it out right now. but the diode i pulled was IDENTICLE to the dioodes in those cheap 300mW 650nm diode module/driver kits on ebay "just search burning laser and sort by price+shipping lowest" should be the first listing. i think it was slightly less than 40 dollars shipped.

but anyways the diodes were identicle and were driven SUCCESFULLY at 450Ma with a full heatsink in a solid metal host, and on a SHORT 60 second duty cycle max. I swear it on everything holy... maybe this 16x is an exception? its the only lite-on drive i've ever worked with so i have nothing to compare...

google that model number i provided, the specs right on their website will pop up if anyone has any doubts. im curious because i also believe a 16X should burn up at around 400ma...but his seems to be an exception. maybe the heatsink is all that keeps the poor little open can alive. and it was most definately an identicle open can diode

EDIT: looking at both diodes again i noticed that the filiments in the center of the pins of the open can look SLIGHTLY different, one little square is darker than the other... but they still handle the same power.. and no difference in beam strength either... just as bright and no brighter...if it was i couldnt notice it.
 
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If you choose 400ma you WILL be overdriving the Laser Diode.

That, of course, is your decision.

I would run a 16X at less than 350ma.

Of course, a A.R. short FL lens will give you at least 10% more output...
and reflect less light back at the laser diode, prolonging it's life.

:whistle:

LarryDFW
 
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thats the thing, i AGREE 100%. thats why i felt the need to post that.. maybe its a freakish diode... but its run on a standard lm317 in a 1 inch aluminum heatsink at 450Ma continuous. i only run it for about 60 seconds though... im kind of lost as to why it doesnt burn out myself, the last diode was going strong for months thatway until it caught a backflash in a mirror.

anyone have any similiar experiance??? im clueless... my diode should be dead according to the pros on here.
 
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I'm not sure you understood what I was saying... LOC diodes and 16x diodes are not the same.

LOC diodes can be run safely up to 420mA and the max for a 16x would be about 300mA. LOC diodes are capable of higher power.
 
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I'm not sure you understood what I was saying... LOC diodes and 16x diodes are not the same.

LOC diodes can be run safely up to 420mA and the max for a 16x would be about 300mA. LOC diodes are capable of higher power.

That's not necessarily true, I've seen LOC's in 16x burners before. The diode power isn't always proportionate to the write speed. I've also seen senkat style diodes in 18x drives.

Just be sure it's not a SHORT open can, like this one:
dsc00304rl1.jpg


These blow at or below 350mA. The difference is the length of the die. A long open can's die goes straight to the back of the casing and all the way to the edge of the mount, whereas these short ones only take up 2/3 the space on the mount.
 
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i actually missread, it was from an 18x drive, one site i used as a reference has a missprint.. wich seems to have been fixed since i last looked... hrm..

anyways its still up and running great at 450ma.
 
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Hmm. That's odd...

In my post above there used to be a picture of a short open can as a reference, but it looks like imageshack.us is having some sort of hiccup right now, and the image isn't being displayed.

Search the forums for "short open can" in quotes if you need a pic to compare.
 
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yeah i noticed that too, i also want to think what i was working with was a short open can... but i bought the SAME exact diode from e-bay and it was claiming to be an "loc" but it was identicle. "to the human eye at least" there may have been subtle differences that i did not notice. BTW this specific liteon drive... was the easiest extraction i've ever done... the diode literaly pulled right out with a small tug on the ribbon cable... never had that happen b4. always had to crack a few heatsinks to get to the diodes.
 




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