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FrozenGate by Avery

1.85A LM317 DDL Driver w/ M140 diode

Photonz

Photonz

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Jun 20, 2013
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I just built (on my bredboard - not recommended) an LM317/DDL Driver to run a m140 diode at 1.85A and it works! I had seen a few threads with people asking about using this driver for an M140 diode and I saw some skepticism. Well now here it is, a working 1.85A driver! Homemade too for very cheap:wave:

182lwm.png


Details:
4x 2.7 ohm resistors in parallel
1x 1.5A LM317 Transistor
1x 25V 10uF Capacitor
2x 16340 Li-ion Batts
1x M140 Diode
 





LM317 is limited to 1.5A with proper heatsinking. I don't see any in your setup. Did you test if it actually puts out 1.85A?
 
Not yet, so it may be 1.5A then. I don't have a test load, or the diodes needed to make one.

Edit: So far it reached 1W with an acrylic lens. Stopped it there so the driver doesn't overheat. Will try to go further with a glass lens and a fan to cool.
2j31l36.jpg
 
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So I transferred the build to an actual board and finished the circuit today. This one uses four 3 ohm resistors in parallel to keep the current at 1.5A which is the LM317 transistor's current limit. Here are some pics:)
1zqt2qg.jpg


Back side
wjw5co.jpg


Nice Lasing:cool:
332ysgl.jpg
 
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So far it's hit 950mW.. recharging the batts and going to try again
2em25iq.jpg
 
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Batteries recharged... 1045mW!
4g5kqd.jpg

1W peak running off two ****fires and using an acrylic lens isn't half bad:D
 
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Not bad. Stick a larger heatsink on the 317 for longer runtime. Are you using a plastic lens barrel? Has it not melted yet?
 
I'll look for a larger heatsink online and the lens hasn't melted
 
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Definitely go with a glass lens, the acrylic works. Until it doesn't! And when it melts the fumes will mess up your diode window, which even after rigorous cleaning will never really be the same.
 
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