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How to make "200mw" 532nm DX module run continuously?

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Jun 6, 2012
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So I picking up 2x of these Dealextreme "200mw" 532nm modules just because of the price (expecting to get around 100-140mw) 200mW 532nm Green Laser Module (3V 11.9mm) - Free Shipping - DealExtreme

In the setting I would like them to be in, I want them to be able to run continuously for maybe 5 hours off of a 3v wall wart. I assume all it takes is temperature control?

They can be in lab-style housings if that's what it takes. I came up with a couple ideas but was not sure if that's all it needs:



  • techhood on eBay Is there something this guy sells that I could place the module in (like a housing with a fan) and still be able to use a wall wart? (I can't tell what will fit a 12mm module either)

The main question: is it possible to run these modules continuously?
 





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Shot aswer: yes.

Obviously the module will need heatsinking, but you will ant to give the driver a dedicated heatsink too- thermally bond a piece of copper or auminum to the main IC.every module I have ever had (which is many), the driver gets stupidly hot if on for extended periods of time.

Also, expect 70-80mw max from these- there are some that will do more, som that will do less, some that wont work at all.

Oh also, buy from fasttech.com rather tha dx. More reliable, and their modules are only about 5$. The will say they are 5mw, but hey are exactly the same as those dx modules. They are pot adjustable, dx just turns up the current and raises the price.
 
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Oh also, buy from fasttech.com rather tha dx. More reliable, and their modules are only about 5$. The will say they are 5mw, but hey are exactly the same as those dx modules. They are pot adjustable, dx just turns up the current and raises the price.

I tried searching on the forum for info about turning up the pot on fasttech modules, to no avail. But it seems like everyone is saying to NOT pot mod...

How will I know the farthest I can turn the pot without burning the module?
 
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Obviously the module will need heatsinking, but you will ant to give the driver a dedicated heatsink too- thermally bond a piece of copper or auminum to the main IC.every module I have ever had (which is many), the driver gets stupidly hot if on for extended periods of time.

Found 91 Heatsink at FastTech - Worldwide Free Shipping

Can I get away with one of these to heat sink the IC? (I have leftover thermal compound from a CPU cooler.)
 
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thermally bond a piece of copper or auminum to the main IC.

It isn't the ICs that get hot on these drivers, but the transistor and large resistor. Here are
some pictures of what you're looking for.

689-SOT-89.jpg

China_SMD_Resistor20107221409506.JPG

resistor.PNG


The resistor is usually okay unless you start really cranking up the pot (see below). It's
the thing in the first photo that needs heatsinking.

I tried searching on the forum for info about turning up the pot on fasttech modules, to no avail.

How will I know the farthest I can turn the pot without burning the module?

I would leave the pot alone unless you're really experienced in electronics and lasers and
don't care if you burn out the module. If you really think you HAVE to pot mod it, there are
ways, but I HIGHLY recommend against it unless you seriously know what you're doing.
You will probably only gain a few mW, anyway.

There are generally 2 types of drivers. The first type has a large surface mount resistor marked 1R0. These are only good up to about 300mA. Going much over that will burn up the resistor, and you will know because it will actually unsolder itself from the board. The second type has a resistor marked 0R33 or a large through-hole part like in the third picture above banded black-orange-orange-silver. These will do more, but the pump diode won't take much more than 500mA.

The right way is to measure the voltage drop across this resistor to find the actual current
going to the laser diode. The pot is backwards, meaning that turning it to the left increases
current.

http://laserpointerforums.com/f51/pot-modding-faq-s-40510.html
 
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You will probably only gain a few mW, anyway.


Even using one of the Fasttech 5mw modules, I will only gain a few mw? crazyspaz was saying they are the same modules as the marked "200mw" modules just with the potentiometer turned up. Could I not achieve the same rating?

P.S. I appreciate the info from your previous reply. That will be really useful.
 
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Yea you could achieve the same powers with both, as they are identical. But as TheLightningStalker said, turning up the pot could kill the diode- ive killed a few by doing this, but ive not been upset by it since they are 5$ a piece. For the price you were originally going to pay for 2 modules, you could get 8 from fasttech- id say order a few extra, so you have some to experiment with, and some backups as well.
 
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Well, as an example, I increased current on one module from about 280mA up to 320mA. The gain was
only about 15mW. Of course the more room there is for increase, the greater the gains.

Also I forgot to mention that the driver will run cooler on lower voltage. If the power supply is adjustable,
the sweet spot is in the 2.8-3.5V range. I just decrease the voltage until the power starts to drop and then
set a little above.
 




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