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FrozenGate by Avery

Direct driving a diode?

jakeGT

jakeGT

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So I harvested my first lpc-815 sled today, it cost me 5 bucks. So I thought, what the hell, lets be stupid. So I pressed it in an aixiz module(first time too BTW), and soldered some leads.

Threw it in a heatsink, and grabbed an 18650, and pressed the leads to the battery terminals. WOW what a bright red beam! the only other high powered red I've had was an 280mW from jeff, and it was considerably less bright.

My question is, when direct driving a diode, how much current does the diode digest? How long will it last doing this, I did it ten or 12 times, but only for about ten seconds each time.

Battery was fully charged, and it didn't dim down at all, or die. SO I was happy just to at least try it out
 





With a fully charged 18650 you should see about 4.1V. That's above the highest point on a LOC's PIV curve, so voltage supply shouldn't be any sort of limiting factor here. Similarly, an 18650 (even a horrible one) can supply more than the 600mA or so that LOCs die at.

In other words, I have no idea how your diode survived ;)
 
It's been going strong strong strong. And like I said, I've done it MULTIPLE multiple times, for more than just a quick on and off, I've even had time to tape the ends to the battery, and adjust the focus to a pin point.

Maybe I should meter it?
 
NO WONDER...
Haha, With a regular aixix red glass lens, 375mW.
 
from laser_freak

It was my first sled harvest, besides a failed attempt at a phr, my first week on the forums.
I broke the heatsink really badly, the diode flew in the air, landed on the table. I figured it would be dead

And 375 was just the start, I did it again, for a few seconds, just because I dont want to kill it just yet, and 390. I wish I had a qumefox acrylic red lens, it would definitely be over 400mW.

But once again, 390 was a ten second test peak

18650 at 4.06v
 
Will do when I get home. Just left for a drunken mcdobalds trip
Don't have any 10440s, just a 26650, 16340, cr2, and 18650s
 


Sorry for the horrible video, I had to hold the laser in it's heatsink so it would hit the thermopile, and hold my freaking goggles up because my dog chewed off one of the ear holder thingys.
 
what kind of battery? If you're using a crap battery, voltage will sag quite a bit on load. I've been sold a 17670 that dropped voltage like a rock with a load much less than an amp.

Also, don't drink and drive. That's what teetotaler friends are for
 
Not that i dont believe you but how is this possible.?

Especially with an Aixiz glass lens.

With the G1 lens i can hit 400mW.

But with the Aixiz Glass lens i get ~ 300-310mW. If i turn up the currant till turning more wont do anything 350mW Max but will die very short after.!!!!

This is the first time i have seen a 400mW LPC-815 with an Aixiz Glass lens. As well as suppling over 1 volt more to the diode. How did this not kill it instantly.

Have you check the batteries in your LPM because i know that when batteries are low it can through off your reading.

Either way Cool.:bowdown:

We better see beam shots.:D

I wonder what it will do with the G1 lens. Can you shot a video with that.? Please please please.!!! PLEASE.!!!
 
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The internal resistance of the battery may cause a substantial voltage drop at higher currents. Can you measure the voltage across the battery while the laser is turned on? I would be interested in the current measurement too. If you can, place an ammeter in series with the diode.

I'm glad you like the diode.
 
:crackup: Well that explains it.:cool: Man I want to see this with a G1 lens or a G2 lens what it will do.:wave:

Iam Guessing over 500mW.:D
 
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I dont have any g-1 or g-2's on me at the moment.

I also feel as if I should keep it put up, since it is such a nice diode, and wait till I can properly build it into something, and run it at 450mA for a while, and see what I come up with
 
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