The Tale of the Ghetto Driver

Ok First off this is my property so don't get mad at me for any of this.

I bought some diodes off ebay. Here

I also bought modules and drivers from aixiz_lasers. Drivers Here.

First off I have to say, I can't honestly tell you what the pin configuration seems to be, I use the TOP as NEGATIVE and either the SIDE OR the BOTTOM as the POSITIVE. I don't understand it... Any way I set up the Driver and it was the same either way. Just to let you know, the diodes are 7mw max. So I tried setting the pot, It was either 0 or 200 mA so I was like what the hell I set it for 200. This driver was supposed to be 80-500mA. So With the me not knowing what the positive was, I hooked it on the bottom. Connected some AAs in series and LET THERE BE... Uh an EXTREMELY DIM diode. This was a 7mW diode. I could barely see it in a dim room. I turned off the light and it was still limper than my willy... I had ten diode so I figured if I blew a couple it was ok. SO I Soldered some long leads on and (Dont get mad) I direct drove the diode and wouldnt you know, it was no brigher... Maybe this was a strange voltage issue. I Grabbed a 9 volt, Completely expected to blow it, I connected it..AND Still the same...And it ran too! What the Hell.

Anyway I don't advise these parts (Or direct driving) at all. Not to mention the Driver is too big for a Aixiz Module (Lol Yes)

I am extremely frustrated. I now see why they are cheap and no one uses them.

What's good ain't cheap and what's cheap ain't good.

Should've followed my fathers advice.

After everything, I can not believe that the diodes are running so dimmly stable on a direct drive 9 volt... I don't understand. A petsmart red pet pointer is 20x brighter And this was supposed to be a 7mw.

I am baffled and disappointed to say the least.

I am sure you vets will probably get a rise out of all this and I am sure this will turn out like 99% of all my other threads but Aw well It is a review and thats what I did. I honestly tried to Blow it up but I couldn't Maybe I should Try a car battery....Lol

Re: The Tale of the Ghetto Diode

The reason they are so dim is because they "died" of COD.
This is commonly known as the "LED effect."

It is not defective, the user just didn't know how to test and power it properly.

Edit: COD as in "Catastrophic Optical Damage." I know many of the "forumites" play a game called "Call of Duty" which, I am aware, is frequently called "CoD" in the gamer community.

http://en.wikipedia.org/wiki/Catastrophic_optical_damage

Re: The Tale of the Ghetto Diode

I couldn't set the driver man, What was I supposed to do?

Re: The Tale of the Ghetto Diode

Make a dummy load and use a cheap DMM to check the driver's current across the resistor(s)

Re: The Tale of the Ghetto Diode

Toaster said:

I couldn't set the driver man, What was I supposed to do?

Click to expand...

Learn from mistakes and do it better next time.

I'm not sure what the operating current is for these diodes, but if the driver can be set to 50mA minimum, try that. It might be too much still, but I've driven some CD drive 650nm diodes up to ~60mA. If you have a bunch of these, it couldn't hurt to experiment.
Otherwise, ask the seller if he can give you a spec sheet for the diode.

Just a guess here, but the diode is probably case positive. The negative pin is probably the isolated pin on the right side when looking at the rear of the diode.

Re: The Tale of the Ghetto Diode

I did, I said I could only get 200 or 0. I cant think of A driver that puts out 30 mA.... Oh the Groove 2. Shoulda Went with that! No need to run a 2$ diode on a 15$ driver, Ha Any way, Even If it wasn't the diode, the driver disappointed me

Yeah I am not too worried. I got the data sheet and It says 30mA typical. Thats SOOOO low.

If you don't feel like paying money for a driver and still have a diode left, you can try running it from a 9v battery with a 200 ohm resistor - this should limit you to about 30mA at 3v across the diode.

Whoa Really?? Sorry I am not good with Elec.. How does that work? I dont see how it would... I have 6 left 4 led'd ones lol

Resistors limit current - they're not as good as a proper driver, but it will work to power the diode. It won't hold the power steady like a good driver would, the power will drop as the battery dies but the resistor will ensure you don't send too much current to the diode.

Yeah I know, It drops volts too though? How many amps are in a 9 volt, I cant understand the calculation

@Pierce

So
Negative
-------Case Positive
Positive

? Thats what it looks like but seems ridiculous

Ohms law - you've got a 9v battery and a diode that will be using about 3 volts. So the resistor will need to drop 6 volts at 30mA.

ohms law: volts = amps x ohms
using algebra we can rearrange the formula to find ohms
ohms = volts / amps

30mA = 0.03 amps so:

resistor value = 6v / 0.03A

resistor value = 200 ohms


batteries in this situation are considered a constant voltage source

Oh Ok, Yeah I dont get Ohms law it seems like LawS because I thought it was
Watts=Volts/Amps

Here is some specs from the data sheet
PowerType Typical Max
current 30mA 40mA
Volts 2.15 2.5
So let me calculate here

Resistor = 2.5/0.04

62.5?

That doesnt seem right...

=6.5/0.04

162.5?

Try using this:
Online Conversion - Ohm's Law Calculator

9vdc with a 200ohm resistor results in 45ma @ 0.405W

Diode not included.............

Toaster said:

Yeah I know, It drops volts too though? How many amps are in a 9 volt, I cant understand the calculation

@Pierce

So
Negative
-------Case Positive
Positive

? Thats what it looks like but seems ridiculous

Click to expand...

The "other positive" will most likely be not used.

Anyway, test the polarity with your LED'd diodes.
The way that gets it to light up dimly is the correct polarity (just not the correct power source).

What do you mean? I powered it using the bottom and the side as positives. I dont get how it could be not used.

I tested all the combinations the only two that worked are Negative on top and positive on side and negative on top and positive on the bottom like so

Negative
---------Positive
Didn't connect

and

Negative
---------Didn't connect
Positive


Ok I am sorry if this sounds dumb, but volts dont fry it, its amps right? Or is it both

If you look at the data sheet, it has a photo monitoring diode in it.
It's listed in the Absolute Maximum Ratings as PD.

Most of these I've seen are listed as 5-7mw 635nm diodes. At 5mw they are at or near 635nm. When you drive them up to 7mw the frequency increases to 640nm with some showing 650nm(@7mw).