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ArcticMyst Security by Avery

2.4a Red laser driver

Joined
Dec 17, 2014
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I'm looking to make a driver for my Mitsubishi g84. I have been browsing every article on making one, and have learned the following:
1. The lm317 won't be enough because it can only supply 1.5A
2. The lm338 will be enough
3. 1.25(ref voltage)/2.4 = 0.52ohms? I don't think i calculated the resistor value correctly...

If step 3 is somehow correct, and i follow this tutorial: Super simple high power LED driver - All
(I know its for led's, but constant current is what i'm looking for right?)

then i hook up my resistor like so:
F6NKCHOFDYPTCVW.SMALL.jpg


and it should theoretically work when i power it using 2x(or 1x?) 18650/16340, correct?
 
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Two problems if you're insisting on an LM338. That heat sink is way too small, and two lithium cells might not be enough to keep the driver in regulation for long, depending on how low their internal resistance is. Current-set resistance calculation is correct, though. Just be sure it's rated for 4W or more.
 
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Aug 26, 2014
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Wouldn't a buck driver with two cells be better for this? The voltage of the diode is around 3 volt (I think), so you would always be in regulation.
 
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Wouldn't a buck driver with two cells be better for this? The voltage of the diode is around 3 volt (I think), so you would always be in regulation.

Im not sure, thanks for the input though, ill look into it. As for the heatsink thing, that's a picture of an lm317 setup, i didnt make it yet.
 
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Ide go with the buck driver.. I was gonna do this build awhile back and have yet to do it. Red diodes have a low volt drop. So let us know what you find for a higher amp buck driver.
 
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May 12, 2017
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Two problems if you're insisting on an LM338. That heat sink is way too small, and two lithium cells might not be enough to keep the driver in regulation for long, depending on how low their internal resistance is. Current-set resistance calculation is correct, though. Just be sure it's rated for 4W or more.


I can use lm 317 as a driver for mis 500-I should use lm 317 or amc 7135 sir
 

Benm

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What are the current and voltage requirement and supply you are using?

This thread is fairly old, but apparently people insist on using voltage regulators as constant current drivers even today.
 

Encap

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I can use lm 317 as a driver for mis 500-I should use lm 317 or amc 7135 sir

Tại sao bạn kích hoạt lại 2 năm chủ đề cũ.

Là rất không thích ở đây - không tốt

Bạn sẽ bị cấm / bị chặn nếu hành vi này vẫn tiếp tục -- Bị cấm từ LPF

Nếu bạn có ý nghĩa Mitsubishi ML501-P73 638nm 500mW diode
http://www.mitsubishielectric.com/semiconductors/content/product/opt/laserdevice/ldindis/638nm/ml501p73_p1245.pdf

Sử dụng trình điều khiển này/Use this driver set for 1.1A for 1W output and set for 520mA for 500mW output is a good chioice --this driver > https://sites.google.com/site/dtrlpf/home/laser-drivers/nano-buck-boost-drivers
 
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