405nm Blue/Violet laser diodes 5-10mW $27 + optics

[drlava]

the side of the diode with the black ring is the cathode; it corresponds with the line in the diode schematic.

The caps have a black bar; that corresponds to the side connecting to gnd in the schematic.

The lm317 pins are numbered 1 2 3 left to right, corresponsing to the numbered pin i nthe schematic

the resistors have no directionality.

The center pin on the potentiometer is the wiper

Hope that helps!

[mliptack]

It does help quite a bit!

There are still a few things I will piece together, but this is great! Thank you! I cannot wait for the driver circuit with modulation!

Just out of curiosity where do you buy your components for the drivers?

the side of the diode with the black ring is the cathode; it corresponds with the line in the diode schematic.

The caps have a black bar; that corresponds to the side connecting to gnd in the schematic.

The lm317 pins are numbered 1 2 3 left to right, corresponsing to the numbered pin i nthe schematic

the resistors have no directionality.

The center pin on the potentiometer is the wiper

Hope that helps!

[Hemlock Mike]

That's a neet LITTLE tube. At first I thought it was in the 100 to 250 watt range. About the size of an old lighthouse tube.
Thanks for the picture.

Mike

[mliptack]

So I spent about 3 hours designing the layout and building my driver circuit, and I figured I would test it out on a blue LED first. It says the voltage in should be around 9 volts, giving the diode about 20-80mA. Well the LED I had was 20-30max mA, so I figured I was safe. I hooked it all up, phhhht. The one ohm diode that was to the ground fried... and took my blue LED with it! Why?

Here are some pictures.

[mliptack]

So I spent about 3 hours designing the layout and building my driver circuit, and I figured I would test it out on a blue LED first. It says the voltage in should be around 9 volts, giving the diode about 20-80mA. Well the LED I had was 20-30max mA, so I figured I was safe. I hooked it all up, phhhht. The one ohm diode that was to the ground fried... and took my blue LED with it! Why?

Heres the last picture. Please note the schematic I drew up is the underside of the circuit, so any lines drawn from different parts are solder lines.

[mliptack]

Forgot the picture... but I think I realized my mistake.

If you look at the 5th picture and click on it so it goes huge.

The left hand side is where the diode would connect, currently (I took this picture before I tested it with the LED) the wires are just there and not soldered down.

Also at the top the second row of holes is the ground loop, (-) power input (also not connected at this point). The only wire running horizontally on the third row of holes is the (+) input for the driver (Also not connected).

OK, so where are the problems I see.

First, Counting 8 holes from the left most part of the circuit, and 6 holes down is the 3rd pin of the LM317K. It should be connected to the (+) Voltage above.

Second, 11 holes from the left 2 down there is a break in the ground loop as I forgot to solder them together.

Those are the problems I see, I know I fried the LED and the 1 ohm resistor, but did I do any damage to any other parts. Obviously its way too late (about 3am) and I need sleep I hope to see your responses tomorrow!

-Max

[MechEng3]

I have tested mine and it seems to get a bit warm from running off a 9 v battery. The diode seems multimode as power is adjusted with the pot...may be a bad/dirty unit. Just wondering if there was anyone else who had a heat issue. Max reading from the unit was 3.97mw. May need to have higher input voltage to get max of 5wm. Any suggestions about the heat? I wil check supply tonight to verify the Vout. There seems a better-simpler supply design is in order for a 12 volt input and a finer 25 turn pot. Any one thought of using a 7805 with a resistor and a cap on the in/out rails? Seems it would be smaller too.

[rog8811]

Here is the 7805 circuit that drives my blue ray, it works just fine as a constant voltage...no good at all configured as a constant current source....
Second pic is the built up driver
third pic is the housing compared to a sentorch

Regards rog8811

[drlava]

So I spent about 3 hours designing the layout and building my driver circuit, and I figured I would test it out on a blue LED first. It says the voltage in should be around 9 volts, giving the diode about 20-80mA. Well the LED I had was 20-30max mA, so I figured I was safe. I hooked it all up, phhhht. The one ohm diode that was to the ground fried... and took my blue LED with it! Why?

Heres the last picture. Please note the schematic I drew up is the underside of the circuit, so any lines drawn from different parts are solder lines.

it looks like you also may have a short from the ground side of the protection diode to the 5.6 Ohm resistor. (the right side of the solder-side picture)

[mliptack]

It does look like it, I have the driver in my car (I am at work now) I will check in an hour or so to be sure. However, I think it might just be the angle of the picture. I dont have cutters that can cut close enough to the circuit board, nor do I have solder wick to pull excess away. And on top of it the soldering iron is in pretty bad shape, so it makes it hard to work with.

EDIT: By the way Dr.Lava, nice job analyzing that, I know I asked a lot from you guys who are just trying to figure out what is wrong from a few pictures.

Do you know if any of the components (besides the 1ohm resistor that blew up) would be damaged by the issues I mentioned.

Thanks,
Max