LPC-815 driver

[Fariniac]

Hello, stupid question time..again....

I have done a search, but cannot find an answer that fits.

I need to build a driver for a LPC-815 Red long can diode, want to get it to abut 250-300mW.

What's the best driver to build for it and supply voltage needed?

Circuit diagram would also be handy

Thanks for you helps guys and girls, Fariniac.



PS: Please don't say "use the search function" I already tried it and couldn't find what I was looking for, I know it's there....just couldn't find it.

 

[k1kb0t]

Try looking here for some more info. If you don't want to buy a driver I think you can find a schematic to build your own.

http://laserpointerforums.com/laser_pointer_forums_3/forum/showthread.php?t=40157

 

[ElektroFreak]

Type "DDL driver" in the search bar..

 

[Fariniac]

ahh, wasn't sure the DDL driver was suitable, always thought that was only for Blu-Ray....D'OH!!...lol

 

[ElektroFreak]

^the current that a DDL driver provides is determined by the resistance that you use. For a current setting that will easily drive an LOC diode to 420mA, use three 10-ohm 1/4W resistors in parallel, instead of the one 10-ohm resistor that is recommended for blu-rays. Using three 10-ohm resistors in parallel rather than one 3.3-ohm resistor allows for more power to be drawn without the resistors heating up too much.

 

[Fariniac]

Thanks for that guys

I know enough about electronics to be dangerous, but not enough to be useful

 

[LarryDFW]

Fariniac;

Here is the LM317 driver diagram for Blu-Ray:

For a Red LD, change the battery to 1 Lith-Ion = 4.2 VDC

Change the Resistor to 4 ohms (1/2 watt) for 312 ma current (or lower for more current).

Negative voltage changes to the center terminal on Red diode.

LarryDFW

 

[Fariniac]

Thanks Larry, I am building that circuit for my blu-ray right now. I have it set to 89ma on a RckStr driver and I am not too impressed with it's visibility (I have it in a nice heatsink so running for a longer time is not an issue) so bumping it up to 125ma should be much better for me

Going to build the driver for the RED later on today, once I have finished messing about with the Blu-Ray..hehe

Cheers, Fariniac.

 

[k1kb0t]

Beam visibility of Blu-ray 405nm is poor. Even after you bump it up to 125ma it still may be difficult to see the beam.

 

[Fariniac]

It's actually pretty good with the smoke machine on, just enough haze to make the beams show up nice

Now, I have a 30mW greenie on which the driver board heats up a lot after only about 10 seconds. The diode is very capable at that output and it has a tight beam. But this heating up has me disapointed.

What do I have to do to make a LM317T driver fit to run that greenie?

Asking a lot of very n00bish questions here I know and no doubt pushing my luck but I figure "hey, it's worth a shot"

 

[ReNNo]

LM317T can make even more heat than "greenie driver".
What driver do you use?
What diode do you use (current, voltage)?
Which betteries?

 

[Fariniac]

I know the LM can produce a lot of heat when lowering Volts or amps, but you can put a heatsink on a LM if you need to.


This is the module I am using atm, the driver is crap it has to be said, but the diode has a lot of power in it

http://s243333424.e-shop.info/shop/...odule-(ACC).html?shop_param=cid=14&aid=OFL27&

As for batteries, it's running off a 6V (going through 3 1n4001 diodes to lower the voltage to 4.5) on a circuit board inside a botex LS-403 Mini Graphic laser unit I bought last week for £10

that 6V output from the board is meant for a fan to run from on an older revision of the board, but the connector is still active.

 

[ReNNo]

OK then.
Just measure current through diode by using 1ohm resistor.
After that use this equation: R=1.25/I
Set pot on that value or buy resistor.

That is what you need to do.
You will need higher voltage to make it work, maybe 2x14500 batteries.

 

[Fariniac]

Nice one ReNNo, I'll set it up tomorrow and give it a bash

Cheers for your help guys, it's been invaluable.

Fariniac.

 

[BShanahan14rulz]

Fariniac;

Here is the LM317 driver diagram for Blu-Ray:

For a Red LD, change the battery to 1 Lith-Ion = 4.2 VDC

Change the Resistor to 4 ohms (1/2 watt) for 312 ma current (or lower for more current).

Negative voltage changes to the center terminal on Red diode.

LarryDFW

Just double-checking. So this WILL work with a red diode (LCC from an LPC815) and a SINGLE Li-Ion? Microdrive (rckstr) wants Vf+ approx. 2.5V, so that is out for me. Just trying to throw together some relatively inexpensive high power reds.

Edit: this worked great. I also used a 1.5W 3.3Ohm resistor to set the current. I went to radioshack and bought a 5-pack of 10-ohm resistors. 3 10 Ohm resistors paralleled is 3.33333 Ohms mathematically. This is now my most energetic burner. Smoke doesn't appear on black plastic; instead, the black surface spits up smoke.