Setting the current on a Driver

Hey so this is my first time posting anything to LaserPointerForums, and I am currently looking at building a 405nm Violet Laser Pointer (The project created by Styropyro). I have found the parts I need; a PHR-803T Sled, an Aixiz Housing, and a Driver, but I have two questions about the driver.

The driver I found is from Micro-Drive V3 adjustable driver (assembled) - $13.00 : rkcstr.com, Micro-Drive and laser diode electronics .
I need the current set at about 100mA, and it is adjustable from 30mA to 440mA. It says it is already set at 55mA to 440mA. Also, does the driver from this website have wires (Positive and Negative) coming out of it? I can not tell from the picture at the site.

So I would like to know, How do I set the current of the driver, and Does the driver have wires coming out of it for me to attach to a power source?
Plus, would I just be better off using a driver found at a different website? As long as the driver is set at 100mA and I can easily connect it to a power source, I will be content.

Please answer to this post as soon as possible, and please suggest a site if you can find a place with a working driver for me.

Thanks,
Connor9195

On that same site you can buy what's called a "test load" or a "dummy load", which you can use to set the current on your driver. The way it works is the 6 diodes on the board simulate the voltage a bluray laser diode needs. Simply hook up the dummy load in place of the laser diode and connect a multimeter across the 1ohm resistor. At 1ohm, 1mV = 1mA, so set your multimeter to its voltage setting to read the current.

And yes, it comes with two wires soldered to the input.

my rkcstr did not come with wires attaced although it did come with them. if you don't want to spend more money and have a little solder/electronics experience you could build your own dummy load. the directions are at www.rog8811.com and there you can also find detaild instructions on how to make your own driver, although it will be much larger. also note that the lava drive and the rkcstr do not use the same voltage. so you could choose driver type according to what host you want to use. example being a small host would take less batteries then go with the lava. a larger host can take more batteries(more voltage) go with rkcstr

pseudolobster said:

On that same site you can buy what's called a "test load" or a "dummy load", which you can use to set the current on your driver. The way it works is the 6 diodes on the board simulate the voltage a bluray laser diode needs. Simply hook up the dummy load in place of the laser diode and connect a multimeter across the 1ohm resistor. At 1ohm, 1mV = 1mA, so set your multimeter to its voltage setting to read the current.

And yes, it comes with two wires soldered to the input.

Click to expand...

i checked the site myself, hmm there is nothing about the test load

I guess this one will help

http://laserpointerforums.com/f51/driver-test-load-phr-803t-schematic-40482.html

Thank you everyone for posting back. I would go with the test load at Test Load KIT (AKA Dummy load, unassembled) - $5.75 : rkcstr.com, Micro-Drive and laser diode electronics , but it is unassembled, and in order to use it for setting my other driver's current, I would need a multimeter; which I do not have.
Also, I do not know if this has anything to do with it at all, but the test load says to have 4.5V-5V running through it. I would be connecting it to a 9 Volt Battery in the end.
Are there any alternatives besides a dummy load available to me? All I need is a driver that would fit inside of an Aixiz Housing, and has a current of approximately 100mA. Oh, and I was just wondering, because the driver is preset to 55mA-440mA, would it be alright to use it right away after I get it, without tampering with it? I doubt it but I just wanted to know.

Thanks again,
Connor9195

since you don't have the tools to safely build a driver or even to test a new one, I would reccomend asking a reputable member here to set it for you. but with all the shipping involved you could have probably bought a cheap meter from harbor frieght. or you can try to pm drlava and ask how much to get you one set to 100ma.

I haven't looked recently but didn't Rkcstr used to offer preset 100ma drivers?
I may be wrong.

@connor.... If you are going to be serious about lasers $10 will get you a multimeter that you will use time and time again, the test load that chip linked too on my site will cost you cents to build and again you will use it all the time.... You have to realise you will never just build one laser, you are on a slippery slope

Regards rog8811

Thanks again for replying to this post. I doubt that I will ever be building a laser after this project is done, so I am either going to try to find a driver already set to 100mA, or just buy a cheap multimeter. Would the multimeter at the following site be okay for setting the current on an adjustable driver? Velleman DVM810 Digital Multimeter
Or should I just look for a pre-set driver? I would rather just buy a 100mA driver, so if anyone knows of a site where I can buy one, or if anyone out there is willing to adjust one for me, obviously for pay, I would happily purchase it.

Thanks,
Connor9195

If anyone has questions about my stuff, feel free to PM me... I'm happy to answer questions.

Anyway, I've gone through a few changes over the the time I've sold my drivers... used to solder on the wires, but stopped after I got the manufactured PCBs. Now, they comes with pre-stripped/cut wire which are pretty simple to solder on.

I used to sell driver which came set to a specific current and were not adjustable, but I've limited my assembled products to the full-range driver because I won't have the time to build anything. I could only afford to have one design factory assembled (it cost a few thousand dollars just to do that), so I stuck to the most popular and versatile design.

But, since I don't have a lot of free time, I can't offer (or even charge) to set the current on the adjustable drivers either. I wish I could, but I'll be having 60+ hour weeks in the hospital as part of my education, so my free time will probably be filled up with studying and shipping everything.

Really, though, you SHOULD have a multimeter if you're working with electronics. You can find them for very cheap (I picked my fiancee up one at Harbor Freight with a coupon for $2!) or you can buy a good one, either way it is a good investment.

OMG this is exactly the same thing i am doing.ROCK ON MAN!

Here is to end all your troubles. Get a lava flexdrive here :Micro flex lava driver
On the order page it allows you to choose if you want the driver's mA preset to whatever you wish.It's great.

If setting the current on a rkcstr driver is a trouble for you, I'd be wary of getting a Flex Driver - it can become a very expensive learning curve.

which 1 ohm resistor do i get?
a 1/4 watt or 1 watt?

OMG!! Ohm's Law?

A 1W one can handle 1A, a 1/4W one 500mA (they will be freakin' hot at those loads, but that's ok).