Who wants to take this project on; host for 15W IR C-Mount Diode

[Alaskan]

LOL I agree

 

[Alaskan]

I found someone to CNC the heat sink and lens assembly, the rest I can do myself.

 

[BShanahan14rulz]

I would recommend you not use a round host.

I would recommend you integrate a remote switch, or an interlock plug that can be used for installing a remote switch.

I would recommend you test the input requirements with a power supply before making a solid decision on your power source.

I would recommend against using the 12V port for charging; only use it for powering the laser.

switch needs to handle the input current too. get a beefy switch.

Maybe try to find a different solution to your client's problem, if that is possible. This device sounds very dangerous, and may not even be the best way of solving the particular problem.

 

[rhd]

I would suggest designing the driver to tie the switch to an enable pin, rather than feeding the actual power through the switch.

Because this peaked my curiosity, it got me looking at high current buck ICs. There are fairly accessible ICs that can regulate in excess of 20A without issue. No need to parallel drivers - one well designed driver can handle this task.

If I owned a diode capable of handling that current, it would be an interesting driver to design.

 

[Alaskan]

I will post results when finished. Thanks for your help everyone.

For my last project I used twelve 120W rated voltage and current adjustable DC voltage step-up constant current regulators which were all run in parallel through separate diodes to a main bus. The voltage and current from each power supply was individually adjusted (currents limited from each) to match one another using a hefty 10 ohm load resistor, this way no one power supply could be driven harder than it's power rating, the individual diodes keeping them isolated from one another.

In that project I was testing between 30-35 VDC at up to 35 amps of total load (not a laser system) and it worked great using several power supplies in parallel for redundancy all drawing their 12 VDC input power through 2/0 welding cable from a 100 amp DC power supply w/marine battery in parallel. I could have done it with fewer units but I also wanted some extra overhead capacity. I never run anything at full power to reduce the failure rate, preferring designs which will handle double what I need from them without overheating due to variable environmental factors, this includes individual components, wherever I can. For the 16W IR diodes I will double the needed cooling capacity relative to the heat dissipation of the diode, operating the device at a far lower temperature than required to increase reliability which will make the heatsink assembly fairly big, but this was never intended to be a hand held pointer, just able to run off of batteries for a period of time if the normal DC input supply fails due to a power outage etc.

For those who say something can't be done, it can't, for those who say it can, it can. You may need to break convention to do so, that is what limits the common man, believing in common limitations to live a life of common mediocracy producing nothing beyond the average.

 

[Alaskan]

 

[KRNAZNBOY]

Dang that is one ugly diode

If it is rated at 15w you should be able to push it a bit IMO.

Its all up to you.

I would imagine divergence is going to suck though

Good Luck
-Matt

 

[Alaskan]

have two of them to work with right now. I want to have two swappable output assemblies, one to get at least a 3 mRad or tighter beamwidth and the other as wide as I can as a line beam. For that, the raw output of the micro lens is a good start. I may have to go to a different diode for a tighter "spot" beam, but I'm primarily interested in a line beam with this one and will add a cylindrical lens after the FAC to enhance it into an even wider line

 

[rhd]

Frankly, if you think about the amount of heat this will need to dissipate, it's not that much greater than a 445... stay with me.

At 2.3 A with a Vf of say 5V, a 445 is pulling in 11.5 W, and releasing say 3 W as light, so thus dissipating about 8.5 W as heat.

This IR diode is pulling in 16 A at maybe a VF of 2.2 ? That's about 34 W, of which 15 W leave as light, so 19 W to dissipate.

So it's s little over twice the heat to dissipate, but it's not orders of magnitude more.

 

[Alaskan]

I always over build my heat sinks anyway, last one I did for a laser weighed about 30 pounds but it had 16 each 445nm lasers in parallel running at 2 watts each. Used active cooling and a DC car radiator fan to suck the heat away but most of the heat wasn't from the lasers.

 

[ryansoh3]

Wow seems like you're quite experienced with building large diode arrays. What other projects have you worked on?

 

[rhd]

Wow seems like you're quite experienced with building large diode arrays. What other projects have you worked on?

I don't know.... if he's properly running his diodes with constant current, not constant voltage, isn't it pretty stupid to run 16 diodes in parallel?

 

[ryansoh3]

Haha, I just noticed that parallel part.
He probably meant series? (I hope.)

 

[rhd]

Haha, I just noticed that parallel part.
He probably meant series? (I hope.)

What's the phrase internet kids say?

"Pics or it didn't happen"

That's the one.

 

[Bionic-Badger]

For those who say something can't be done, it can't, for those who say it can, it can. You may need to break convention to do so, that is what limits the common man, believing in common limitations to live a life of common mediocracy producing nothing beyond the average.

Oh spare us the platitudes.

We'll judge a man by what he actually does, not just what he says he does or says is "possible."

 

[Alaskan]

A link to my last laser project: IR, LED and Laser Project

Tell me what is possible instead of what isn't, many things have come into being by someone pointing out what can be done and others to do so later and they are just as much a part of the process as the builders.