HLD685035K5J 685nm 35mW Diodes

Yeah 690 is expensive, around 60 bucks a diode for a nice one. 700 is a bit odd all the way around. 780 is cheap as those are CD reading diodes generally. And we all know and love 808 & 856 for their DPSS properties.

I have built two 685nm using these. It comes with three diodes, you just have to remove the Al "wings" with pliers. I don't think it's the same diode but specs are very close. I also run mine around 50-60mA for about ~30mW, and they produce nice single mode dots.

The one I built last (on a 501B host) uses an AMS1117 driver and can be run with a single 18650, but loses considerable power.

Funny thing is that I had a hard time picking the color difference from my first build to 650nm but with the new build it's detectable even by non-laser people. It looks more "crimson".

Wish we could get these at a power high enough to see the beam.

Just finished biulding a pen laser using these diodes, (Thanks, Atomicrox for the link).
I used a AMS1117 SOT-223 for the driver. I have it set at 56mA, which when I originally tested it gave 35mW.

And... it runs with one Li-ion, 19mW.
Haven't tested the completed build with two batteries yet, but when I tested it during assembly the current seemed to drop about 1mA a second, I was thinking because of the driver getting too hot dropping the extra voltage.:thinking:

Update: with two Li-ion batteries it does 24mW.

I'll probably make a build thread soon.

EDIT: Build thread made: http://laserpointerforums.com/f50/685nm-laser-pen-build-picture-heavy-92431.html

That's cool, congrats on your new laser!

Power on mine varies a lot with a single batt (all the way from 16mW to 4mW, depending on batt charge/quality). With two batts it does a very consistent 32mW, don't remember ever seeing the power drop.
The driver does get a bit hot but I don't think that's a problem - we're not even using 10% of it's current capability after all!

I still have one diode left. Thinking of either building one at 5mW or trying to overdrive it (other members have said it's easy to kill).

Just been thinking, when I was testing the driver and the current was decreasing I was using one normal diode as a load. That might have caused the extra heating?
I'll probably make the other diodes into a 5mW pen, and a C6 at somewhere around 35mW.

Not sure if it could cause that, I think you're supposed to use a resistor in series with many diodes to make a test load (a single diode doesn't have enough voltage drop).

I set mine with a fixed resistor based on the formula on the voltage regulator's datasheet. After that I measured the "tailcap current" and it was as expected - since it's a linear regulator it has to be the same as the diode current.