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ArcticMyst Security by Avery

Accident+ what would happen?

Newb

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Today, I was building my 2w m140 laser today when my soldering connections broke and short- circuited the driver, luckily my diode wasn't hurt (just my luck...). My question is while I was building it I attached the diode to a 9v battery without thinking, only for about 5 seconds before I realized, but how much damage does this really do to the laser?
 





Blord

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Not much. The 9V battery doesn't deliver enough current to kill the multiwatt diode.
 

Blord

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With a 9V battery you will never get 2 Watt from a laser.
Actually I never tried direct drive with a 9V battery. Buy a new driver for the laser.
 
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If you use a fully charged or fresh 9V Battery to directly
power your LD... you may very well damage the LD by the
initial inrush current spike...


Jerry

You can contact us at any time on our Website: J.BAUER Electronics
 
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Newb

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What if I use a used 9v battery? I tested it and it's outputting 8v at about 3a
 
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Is it really worth taking the risk? As has been pointed out above, you are liable to destroy your diode if you get a current spike on start up....I wouldn't risk a 45$ diode messing around with a 9V battery!

Just buy a new driver, it'll be much cheaper than a new diode! Blord is selling them here for a fantastic price: $6 Mohgasm drivers. If you want 2 W then Id take the 2.2 and 1 ohm resistors to get 1.82 A, which should get your 2 W.

If you dont want to try soldering the resistors on, you can get completed ones here:
cajunlasers :beer:

Edit: 3A is too high for an M140 445 diode!
 
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Newb

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None of those drivers are enough to power my laser, but I do have a 500ma driver lieing around, do you think if I use the 1.25a driver and my 500ma driver. It would be okay to. Power my laser?
 
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:thinking: Now Im confused! If you have an M140 diode you should run it upto max 1.8 A. On blords page you combine 2 resistors..ie solder on the 2 resistors mentioned and together they give a total of 1.8A...

If you want less you just choose two others that give a sum total of less...

On the website (Cajunlasers) that sells complete drivers, they do have 1.8 A under "driver boards". Heres the link: Mohgasm 1.8A linear driver circuit [MOH1.8] - $14.99 : Cajunlasers Store

You can often combine drivers in parallel (flexdrives or benboosts etc), but that is dependent on the drivers. I would have to let someone else chip in here, because I dont have sufficient knowledge of electronics.
 

Newb

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No I am saying I already have a 500ma driver, so if I buy the 1.25a driver from blord, which totals 1.75a would THAT be okay to run this diode?
 
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It depends on the design of the Drivers...
You can not put two different manufactured Drivers in Parallel..

And even less desirable is to put two non identical Output current
drivers in parallel...:eek:

It is simple................
Get the proper driver and stop trying to put a band-aid solution
on your requirements.

You can easily run your 445 LD on 500mA with less beam power
and greatly extended life...


Jerry

You can contact us at any time on our Website: J.BAUER Electronics
 
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Ok Im waiting on a reply from Blord, but again it will depend on your driver as to whether you can combine them.

You would still be better off buying a new driver, because if you buy a new one at 1.8 A it will cost the same as one at 1.25 A and youll have a spare 500 mA one for another build. Not to mention the added complexity of having to parallel the drivers, if it indeed can be done.

If you really want to run 2 in parallel you should provide details of your 500 mA driver and wait for one of the driver / electronics experts to comment.
Good luck :beer:


Edit: Thanks Jerry you just beat me to it! ;)
 
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Blord

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The Mohgasm driver that I am selling is only good to 1.25A. For higher output you will need another board. The two resistors is placed ONLY on one board.

I see a lot of people want to make 2Watt lasers but that isn't easy. They think "I need 1.8A driver on the 445nm diode and voila a 2 Watt laser is born"
First not every 445nm diode can hit the 2 Watt mark
Second you will need at least a G1/G2 lens instead of the standard glass lens
Third heatsinking the diode and driver is critical.
 
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Ok got it! Didnt realize that was the case, as Mohs linears usually go higher.
Thanks for clearing that up.
 




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