Micro-Drive laser driver by rkcstr

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

if theres anything i can do to help you out i will but until then im waiting for you to start taking orders again... :'(

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

Having ordered a couple drivers for my first ever lasers a day before he posted being unavailable, I really hope he does well in medical school, and also finds time for this hobby as well. Best of luck rckstr, and I am anxiously waiting for my drivers.

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

GodXanatos said:

I really hope he does well in medical school

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Me too  

Hope to have all orders that haven't been shipped out done soon. Thanks for your patience!

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

rkcstr said:

[quote author=GodXanatos link=1206947255/520#529 date=1238556833]I really hope he does well in medical school

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Me too  

Hope to have all orders that haven't been shipped out done soon.  Thanks for your patience![/quote]

Great! looking forward to receiving them and putting them to good use!

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

Ok, got my drivers today. A few questions. First, which way is IN (from the battery) and which is OUT (to the diode)? I'm guessing the surface mount area is the one that goes out to the diode, and the thru-hole is for the battery connection. And GD = ground (negative?) and LD means ? (positive?) .

Also, I got my test load, but I am wondering why somebody has decided that the load will be used for red? Because it has already been soldered, what gives? Now I have to de-solder it and I have no de-soldering wicks or suction pump things. So this sets back my build until I can get the solder off and re-solder for Blu. And last time I tried to de-solder something, I totally screwed it up, so there is a chance I may ruin this dang thing trying to get the solder off. In the future you should never assume these kinds of things. Just leave it un-soldered.

And where do I put my multimeter connections, I see the holes...but there is no labeling for which is COM and which is for the Ohms one (with Ohm symbol on my MM). Also, this 1 mV = 1 mA formula, does this work for other drivers and other things besides your drivers?

Anyway, thanks for getting my order out, cause I see your site now reflects that you are busy with school...so it looks like I got my order in just in time.

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

Ok.. first off, there are instructions posted on my website, in the descriptions for each item.  Yes, the thru-hole are the input, the LD is positive diode output, GD is negative diode output (but it is common to the negative input as well).

Next, the Test Load.  Out of the (many) hundreds of these things I've sold, you're the second person to ask about that and the only one to complain... so congrats.  I don't do anything without reason, though.  And, you DON'T have to use desolder wick or a vacuum pump, just heat up the joint and it will likely break itself.  If not, hit it with a little flux and try again (if you're soldering, you should have flux).  

Anyway, the reasons for why I set it are:  if you power the test load up without a setting, you'll pop the small resistor on there almost instantly at any substantial current.  Since the output voltage does NOT matter if you're just setting the current on my driver (most common use for the Test Load) and using the RED voltage allows for the minimum amount of input voltage to the driver, that is what I set it to.  Plus, I've been doing that since I first made these, which is when red diodes were more commonly used, so I continue for the sake of consistency as well.

When measuring on the test load, it doesn't matter what hole each lead goes to as you're just looking at the number, not the sign.  So whether it is positive or negative makes no difference, the integers will be the same.  The forumula "1mV = 1mA" is derived from Ohm's Law since you are measuring the voltage across a 1 ohm resistor to find current.  Where V = I * R, you see R = 1, so V = I * 1 is the same as V = I, or if using the units, 1mV = 1mA.

Let me know if you have any other questions.

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

Sorry, I didn't mean to offend you at all, I am just clueless about this sort of thing. I have zero experience in this feild, and sometimes I over analyze and confuse myself even further. I read up as much as I could before asking those questions, I read the site descriptions and this thread. I didn't get the answer I wanted so I figured I would ask here. And you definitely answered my questions, so thank you

But I do have another question. I have hooked up the fixed driver that I wanted set to 139mA. I have the + and + all connected and lined up and the - and - lined up. I left the blob of solder on the red option cause I came to the realization that it doesn't really matter as long as the volts were correct. I just wanted to test the mA output.

So I connected a 3V primary lithium battery and did the test. my MM is set to the lowest voltage setting (.000) and when I connect the battery I get a reading of this .006

I am not sure what to think about this...I am guessing I need to put a few more volts in to get a accurate reading? Would using 6 volts with the red option selected be a bad thing?

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

leukoplast said:

So I connected a 3V primary lithium battery and did the test.  my MM is set to the lowest voltage setting (.000) and when I connect the battery I get a reading of this .006

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The test load is pulling about 3V at the "red" setting.  The driver is pulling about 2.5V.  You need at least 5.5V at the power source to get the driver into regulation.  Increase your power source to 6V and you should get a very different reading.

If you have it set up for violet, you will need about 7.5V (5V for the load and 2.5V for the driver)

Peace,
dave

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

Yeah, I just tried with 5.72 volts and got a reading of .138

I got it now, thanks!

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

leukoplast said:

Yeah, I just tried with 5.72 volts and got a reading of .138  

I got it now, thanks!

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SWEET!

Peace,
dave

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

It's not a problem, I'm not offended.  But, I did want you to know that the setting was not arbitrary.  And, it really is simple to change the setting on it.  Just takes a quick heat on the blob of solder to get it to break, most of the time.  Using flux will "wet" it more and make it ball up more easily, so that will help if you can't get it to work with just heat. Then later, if you want to set it to RED again, you can leave the BLU connected and just use a little solder on your tip to reconnect the RED pads (meaning both RED and BLU are connected) and it will work just the same as RED only. Then, you only have to disconnect the RED to get the BLU setting.

Anyway, thanks for being my volunteer tech support, Dave

Re: Micro-Drive laser driver *NOW ADJUSTABLE*

rkcstr said:

Anyway, thanks for being my volunteer tech support, Dave

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You have studying to do

Peace,
dave

I have a quick question for anybody willing to answer. Is the test load supposed to get warm when doing testing on drivers?

Cause when I was testing my DX 5mW red laser driver which was running at 168~ mA at the time, I noticed afterwords it was a bit warm. I just want to make sure that is normal and that I am not hurting it.

leukoplast said:

I have a quick question for anybody willing to answer.  Is the test load supposed to get warm when doing testing on drivers?

Cause when I was testing my DX 5mW red laser driver which was running at 168~ mA at the time, I noticed afterwords it was a bit warm.  I just want to make sure that is normal and that I am not hurting it.

Click to expand...

It will get very warm if you leave power to it for awhile. It is the resistance in the diodes that simulates the load. Resistance = heat.

Peace,
dave

Ok, that's what I thought. Thanks for the confirmation

I too wish rkcstr welll in his studies (and his residency). Looking forward to buying a few kits when the dust clears!

Burgess (}}}>