Micro laser driver - fits Aixiz/DX modules

Something I have been developing for a while now, a small driver able to drive high powered laser diodes and fit fully within the Aixiz/DX module.  I wanted to post it up here to see what people thought and to let the people who may have already known about it to get more information.

The drivers are available for purchase, see this thread for details.

The specifications:

• A micro-sized driver designed for high power output but able to fit the smallest of applications, including the Aixiz laser module.
• Based on the MC33269 low drop-out regulator.
• Solders directly to the laser diode with standard pin-out (both PS3 blu-ray diodes and standard 3 pin 5.6mm red diodes)
• Capable of driving a red diode with an input voltage of ~5.25V, a violet (blu-ray) diode with ~7-7.25V, or generally >2.25V more than the diode's voltage, compared to >3V necessary for LM317-based drivers.
• Output current is preset in one of the following values:  38ma (for blu-ray), 50, 100, 150, 200, 250, 300, 350 or 400ma.
• Due to the small size of the driver, higher output drivers will have shorter duty cycles (on-time) than with lower output.  Duty cycle will vary, but with 6V input driving a 3V load @400ma, the temperature peaked at around 85C within a 2 min time period, in one test performed.  Higher input voltage will increase the temperature and decrease the duty cycle.

For those who are good with a soldering iron/hot air rework, I can offer an SMD resistor 'kit' of all the resistors you would need to change between the offered voltages as well.

I intend to have these for sale in the near future.  For now, I am waiting on an open can diode for me to test with as well as someone else's test of the driver.

Let me know if you have any questions or suggestions.  

Update (3/25/08):
I received my open can yesterday and have been having plenty of fun with it  ;D  I was able to run it for over 3 minutes at 400ma just within the DX/Aixiz module with no problems.  The case did get rather warm, but never too hot to hold, it probably could have kept going.  I won't recommend running it for that long, but it at least shows it's possible.

Pics:

what will the supply voltage need to be?

robjdixon said:

what will the supply voltage need to be?

Click to expand...

Try checking the post above yours for that information.

Hmmmmmmm.....

Good stuff!  That's based on the same chip I used for a few of my mods (just a different case style).  I see you have the 400mA version there.

http://www.laserpointerforums.com/forums/YaBB.pl?num=1188569731

i like what you did here you put the regulator on the opposite side to conserve space i never though of that, i have some lm317's in this package time to go etch a pcb

chimo said:

Good stuff!  That's based on the same chip I used for a few of my mods (just a different case style).  I see you have the 400mA version there.

http://www.laserpointerforums.com/forums/YaBB.pl?num=1188569731

Click to expand...

It's actually the 800ma chip, but I'm only using it for up to 400ma. The reason being, first most can diodes I've seen probably can't handle much more than 400ma, at least not without major cooling, which means the laser's not going to be very small and you can afford to use a bigger, better cooled driver. Bringing me to the second point, the driver's too small to safely drive 800ma. It's quite possible that you could run it for a few seconds at that output, but it's going to heat up VERY quickly.

rkcstr said:

[quote author=chimo link=1206339013/0#4 date=1206360362]Good stuff!  That's based on the same chip I used for a few of my mods (just a different case style).  I see you have the 400mA version there.

http://www.laserpointerforums.com/forums/YaBB.pl?num=1188569731

Click to expand...

It's actually the 800ma chip, but I'm only using it for up to 400ma.  The reason being, first most can diodes I've seen probably can't handle much more than 400ma, at least not without major cooling, which means the laser's not going to be very small and you can afford to use a bigger, better cooled driver.  Bringing me to the second point, the driver's too small to safely drive 800ma.  It's quite possible that you could run it for a few seconds at that output, but it's going to heat up VERY quickly.[/quote]

Sorry, I meant that's the 400mA configuration (4x parallel 12R4 resistors). Cheers,

Paul

chimo said:

Sorry, I meant that's the 400mA configuration (4x parallel 12R4 resistors).  Cheers,

Paul

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OK, gotcha

hi guys im trying to build same setup as this driver, about the resistor how much value do i need to run LG 4x bluray burner? how much mA needed for that? thanks

hey adjemin it depends on how much ma you want from it pm me
i can make you a driver or send a schematic fo you to etch your self

hi toked can you send me some schematic for this micro driver here? thanks

Is that current regualting or just voltage?

desslok said:

Is that current regualting or just voltage?

Click to expand...

It is a current regulator.

What if we mount a heat sink on the regulator? That should increase duty cycle :-/

Switch said:

What if we mount a heat sink on the regulator? That should increase duty cycle :-/

Click to expand...

How long are you looking to run your laser at a time?

I'm sure you could mount a small heatsink to the top of the chip or solder a heatsink to the board to decrease heat build up and extend on-time, if you had the room.

I intended this to be used to make a compact portable high power laser,  not so much a lab-type laser designed for long time periods.  An open-can diode mounted in an aixiz module will heat up quickly at 400ma, which I would be more concerned with the diode failing than the driver.

EDIT: Check out my update in the first post... I had my open can running at 400ma for >3min.