help with 1.6w driver from ali/ebay

[milantheone]

hi guys i am sure you are familiar with this driver, i would like to ask you if i need to change some resistor to get full 1.6watts out of it..??

as mine gives me 300-600mA on a dummy load, with potentiometer all the way left-right.. something isnt right..




The driver closeup:

 

[Amak87]

What voltage are you pushing your dummy load at?

 

[Amak87]

You’re going to have a voltage drop from the power source to the driver. It’s best to test and set CC drivers using the exact power supply you’re going to use in the end installation.

If you’re inputting 3.7V, then that’s definitely too low, 3.7V is essentially a near empty Li-ion. You should apply 4.2V to this driver, and you really should do it using an actual Li-ion battery, with the same length and gauge wiring you’re going to use in your laser pointer, this will allow you to have a much more precise setup.

With 4.2V in, and if youre going to use a bench power supply, then set the CC limit to 2.5A, as it states in the specs. You should be getting 5.5-6V output with a max current output of 1.8A/1800mA.. also, if you’re going to adjust the current via potentiometer, it’s best to do this with the power OFF, those things are sensitive to getting shorted if you’re not using a plastic/rubber handle screw driver. Be careful when turning that PoT, cuz they are cheap and can easily pop off and break. I like to adjust them, with the power supply OFF/disconnected, using a flat head screw driver, and very light pressure, making small adjustments.

You also have to make sure your dummy load is setup properly to pull the current your trying to adjust for, obviously.

Hope this helps.

You should post some pics of your wiring setup and how it’s all being hooked up.

 

[Amak87]

Also, just my personal opinion and I’m sure many laser builders here would agree. But this style of driver, for a 1.5-1.6W blue laser diode isn’t ideal. The back of the diode is where the most heat is generated, and this driver doesn’t allow for proper a heatsink mount of the diode. What style of host are you installing this in ? It would be much better for the life of the diode and optical output, to use a 12x30mm Solid XL copper module from Barnett Unlimited. This would allow you to mount the diode into a copper shell, and it threads onto a solid copper back half that seats the back of the diode against copper. Using some thermal paste, you’re going to have substantially higher efficiency and heat dissipation from the diode.

I would recommend buying the C6 host kit from SurvivalLasers.com, with a 17mm round driver, getting the extended/tapered copper heatsink, and getting that XL solid copper module from Barnett.. if you want I could build this setup for you if you wanted to order the parts and ship them to me, I’ll even record a video so you can see how to the process is performed properly and professionally..

 

[milantheone]

thank you for extensive reply, thing is i used 18650 battery fully charged.. module will be copper without solid back.. plus aluminium block heatsink around 22 x 40 x 27mm..

as a dummy load i used our standard method, with using 1N4001 and 1ohm resistor.

this might be issue.. i used 5 diodes and resistor, and voltage measured acros them was around 5,3V so probably in the ballpark of actual LD. with that setup i got maximum of 600mA.
later i found out that if i want to measure more than just couple hundret mA, i might use less diodes. So i reduced the nubmer of diodes to 3 or 4 and i got voltage drop of just around 3,6V.
now i was getting 1050mA from the same setup..

so basicaly i digress to test any further.
i just wanted to know how much mA/A will i drive my didode with, and also to use all the potential the diode offer.. but it seems that driver is not that cappable.

i know the driver will not kill my diode, obviously.

 

[Amak87]

Just plug your diode into the setup and set it that way.. it’s going to be the best way to ensure a properly set setup

Also, if your 18650 battery is low end brand, you may not be able to even push the proper CDR that setup requires..

Why not just set it all up with the diode you’re going to use, and use an LPM to dial in the current? Honestly that’s a much better way since you’ll be able to see the actual performance of the diode. As you know, they’re all different, so just setting a certain current and then connecting your LD into the circuit isn’t the best way unless you have an LPM.. it’s like trying to tune a race car using someone else’s flash, you may get close to a decent result, but without monitoring and tracking the end results, you really won’t have any idea of how it’s performing..

When I set my SXD drivers with a 7-8W blue LD, I could care less what the current is. I solder everything up in the finished product/host, and then use my LPM to see the LD output and make changes that way. I can easily see when the current is too high, regardless of the actual value, I can see when the output is stable or not and if it drops off fast or nice and steady.. I only pull out the multimeter and solder up some leads if an issue arises and I need to troubleshoot the circuit. It’s also best this way because you’ll have the actual heat dissipation qualities of the setup, VS using longer leads and using a dummy load that’s not going to act the same as the LD used..

But I really don’t suggest using adjustable CC drivers when there are so many options out there to yield the desired result.

Convoy drivers are really nice, they have adjustable groups/current settings. Temperature control and if you really want to dial in a specific setup, then swap out the negative lead resistor. I’ve had more drivers fail with POTs than the preset drivers. Adding a moving part into a system that doesn’t require any moving parts, is wack to me lol