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Help me choose the right Driver

Gianakakis

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Hello, guys Firstly I want to introduce myself because I am a very new member My name is Giannis (Eng John) And I come from Greece I am also 14 years old.
Recently I have built an m140 based laser I used a homemade LM317 driver and the diode was working fine then it died (That was my fault, not the driver's)
I have already ordered a replacement from eBay and I also have these very useful Buck-boost boards from eBay with ajs voltage, ajs current, current limit, and voltage limit. I was wondering if I can use one of these in place of my lm317 driver here is the link for one of those boards if you are interested: https://ebay.to/2LwFAzM
I am also planning to use this Voltage/Ampmeatres: https://ebay.to/2HLXtU3
Thanks a lot and have a great day,
John
 



paul1598419

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I am not familiar with this driver, but it may work. Unfortunately, you picked a driver that needs a lot of setup before you can use it for anything. The maximum current to drive an M140 is suggested to be 1.8 amps. This should give you over 2 watts out if you use a single element aspheric lens. You will need to get or build a dummy load to use to setup adjustable drivers as you cannot do this without one.
 

Gianakakis

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Thanks a lot for your suggestion Paul I wasn't even thinking to build a dummy load. I was planning to just set the voltage to 4.6v and then slowly increase the current but I think that your method will work a lot better. And yes I am planning to use a three layer coated glass focusing lens. Also can you please provide me with a schematic for an M140 laser dummy load to built it myself or a buy link?
That would help a lot. Thanks for your help,
John
 

paul1598419

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Search "test load" or dummy load for driver setup. You should be able to find it using one or the other.
 

Gianakakis

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Also, Paul can I ask you a question? I was in the market for a cheap green laser pointer I did not buy the cheap-o 301 and 303 lasers and I bought the one listed on Sanwu lasers for 15$. Is the sanwu any better than the 301s and 303s?
 

Lifetime17

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Hi
For your driver you can get a SXD set to 1.8a from DTR laser shop he can set it up for you if requested.
That will run the M140 diodes
Rich:)
 

Gianakakis

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Thanks a lot for your advice Rich but sadly I have to either build the driver myself or use the board I mentioned above but again ill keep your advice for future reference.
 

paul1598419

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Also, Paul can I ask you a question? I was in the market for a cheap green laser pointer I did not buy the cheap-o 301 and 303 lasers and I bought the one listed on Sanwu lasers for 15$. Is the sanwu any better than the 301s and 303s?
No, the lasers are exactly same. The only difference is the Sanwus are said to be measured for output power. I have my own meters and can easily do this myself. It isn't worth the extra $9.00 plus shipping to get Sanwu to do it for me.
 

Gianakakis

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No, the lasers are exactly same. The only difference is the Sanwus are said to be measured for output power. I have my own meters and can easily do this myself. It isn't worth the extra $9.00 plus shipping to get Sanwu to do it for me.
That's a shame I thought that for the extra price they might include an IR filter.
Edit: Yea do you think the board will be safe for my m140? here are some specs
Output voltage: Continuously adjustable(1.25-25V unload adjust)
Output current: 3A Max
CC range :0-2A (adjustable)
Minimum voltage difference: 2V
Conversion efficiency: 80%
I am planning to power it using 2 18650 High discharge cells from an old laptop battery
 
Last edited:

paul1598419

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I would not be too concerned about the small amount of IR leakage. At most it is 20% of the output power. Worst case for an 80 mW one is 16 mW of IR. It is mainly collimated with the visible light, but does diverge much faster. If you are worried about the diverging beam, it isn't dangerous as by the time it diverges much, it no longer is even great enough to deliver 5 mW.

On the driver, you will likely be able to use it, but will need a dummy load to set it up.
 

Gianakakis

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I would not be too concerned about the small amount of IR leakage. At most it is 20% of the output power. Worst case for an 80 mW one is 16 mW of IR. It is mainly collimated with the visible light, but does diverge much faster. If you are worried about the diverging beam, it isn't dangerous as by the time it diverges much, it no longer is even great enough to deliver 5 mW.

On the driver, you will likely be able to use it, but will need a dummy load to set it up.
quick update guys the circuit works. It can power up to 25 volt laser diodes and itcan provide upwards of 2.2 amps of constant current photos included below
The laser driver also has an internal safety switch the blue thing it cuts off power to the outputs
 

Gianakakis

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My mitsu 150mw red died today I thought that the operating voltage of red diodes was 5-6 rip but the driver is doing good and it's rock solid red=voltage and blue = amps
 

paul1598419

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It doesn't look like you are using a constant current driver for this. If you are using a power supply to drive it you need to limit the current to the diode or it will increase as the diode heats up.
 

hakzaw1

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Hello, guys Firstly I want to introduce myself because I am a very new member My name is Giannis (Eng John) And I come from Greece I am also 14 years old.
Recently I have built an m140 based laser I used a homemade LM317 driver and the diode was working fine then it died (That was my fault, not the driver's)
I have already ordered a replacement from eBay and I also have these very useful Buck-boost boards from eBay with ajs voltage, ajs current, current limit, and voltage limit. I was wondering if I can use one of these in place of my lm317 driver here is the link for one of those boards if you are interested: https://ebay.to/2LwFAzM
I am also planning to use this Voltage/Ampmeatres: https://ebay.to/2HLXtU3
Thanks a lot and have a great day,
John
Please make a 'proper' introduction of yourself in the WELCOME section and put 'Greece' in your thread title to find others near you.. we like to hear about you--your goals with lasers etc. other hobbies etc.
You may need to read the TOS (terms of service) as we are not legally/morally allowed to sell you handheld lasers over 5 mW.
AND you are not 'allowed' to buy/order them either.
IF an adult buys these for you ... we are not responsible--they are.
 

Gianakakis

Member
Joined
Apr 27, 2019
Messages
66
Points
18
Please make a 'proper' introduction of yourself in the WELCOME section and put 'Greece' in your thread title to find others near you.. we like to hear about you--your goals with lasers etc. other hobbies etc.
You may need to read the TOS (terms of service) as we are not legally/morally allowed to sell you handheld lasers over 5 mW.
AND you are not 'allowed' to buy/order them either.
IF an adult buys these for you ... we are not responsible--they are.
Yea I know that I can't buy them but my dad orders them from eBay if I ask him to and fortunately I'm not the guy that shines powerful lasers at airplanes please read my post here about the safety measures that I take https://laserpointerforums.com/threads/a-plea-for-eye-safety.51464/page-12#post-1561905
 




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