Waiting on my 5w C-mount diode

Here is a video of the Lab unit Im making for a 5W 808nm diode Im waiting on from Chris at heruursciences. When I get the diode have to do some final machining on the sink/collimator and I should be ready to burn. I will post a video when I get it going.

Right now Im burning testing the powersupply at 10amps. I will only need about 6.5 amps for the diode so this is a good test.

regards
sbdwag

YouTube - cmount ready

What exactly were you pumping 10A into for this test, it kinda looked like the leads were just shorted together :thinking: I sure hope Chris ships it quick cuz this build is gonna be neat!

Its 5v out and I was dumping across .5 ohms of resistance thru that big wirewound resistor on the side of the box. Thats a 0-1 ohm ohmite 50W varible resistor. When I add the 2 volt drop accross the diode I will have 3 volts to play with. So at 6.5 amps Ill dump .65v accross the .1 ohm current sensing diode and then I will have 2.35 volts left to dump across the varible resistor. 2.35/6.5 so I will set my varible power resistor to .36 ohm or so to use control current correctly. The Array of big resistors on the pcb are .1 and 1 ohm power resistors. The jumpers allow me to parallel them if needed so I can use the full range of the 50w power resistor from about 1.5 amps all the way up to 10 amps. The power supply is capable of 12 amps and no I was not shorting it out.

It very easy to control the current . You take the supply voltage subtract the voltage drop accross the diode. Then divide that by the current you need and the results will be the total series resistance you'll need in the circuit to provide that amount of current.


Regards
sbdwag

Awesome sbdwag, thats one of the most complete and over the top answers i think i have ever gotten

Ok
How bout

That big ass brown thing with wires running around it is a big half ohm resistor. Thats whats connect to the wires.

regards
sbdwag

Now your talking my Language...

MISTERWILLING said:

Now your talking my Language...

Click to expand...

HAHA!! :crackup:

We can't wait to see how this baby burns Wags. Be safe as I know you usually are. Five watts of diode power is in the "Big Scary Laser" category. ;-/

Millirad

Yep i plan on being safe Im concerned about focusing the 5W without safety glasses on I will probably shield myself behind a camera. I got the C-mount diodes from Chris the other day almost have the machining done on my heatsink/collimator mount (I will post pics and a print of the design).

The specs on the 5W call out 5.2amps for 5W's which is a very high watt/amp ratio. It also says max wattage is 7W. So I have got room on the diode to play with.

Some photos of the diodes





Im going to start out with a 2W diode because I want to be very careful and not trash my expensive 5W.

When I get it going Ill post some videos and Pics.

Thanks

sbdwag

Such unassuming packages, then BAM, 5Watts of laser light!

You built yourself a very professional looking Power Supply...
At those currents... the only thing that I would add is a Digital
Ampere Meter Display showing the actual output current to
the LD...

Something like this....
http://cgi.ebay.ca/3-12V-Digital-Blue-LED-50A-DC-Amp-panel-meter-shunt_W0QQitemZ250490853944QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a526b1a38&_trksid=p3911.c0.m14

Can't wait to see this this do it's stuff....


Jerry

Laserbee

Thanks for the comments. Im thinking about adding a voltmeter or ampmeter. Since this is really not a constant current device rather a series resistance device Im looking for fluctuations in current. It would be cool to monitor the voltage across the laser diode but more practical to just measure voltage across the .1 ohm current resistor. Maybe multiply it ten times with a LM741 and display it on a digital voltmeter. But that may occur in my next iteration.

Regards
sbdwag