Ebay Driver

[Andrew124C41]

Laser Diode LD Driver Board PCB 4.5A for 3.5W NDB7A75 3 Modes High Low Strobe | eBay

This Laser Diode Driver PCB 4.5A Constant Current can be used to drive 3.5W NDB7A75. This is a 4.5 Amp laser diode driver with 3 modes, high, low, and strobe. Most people will use 2 Lithium ion IMR or INR batteries at 8.4 volts.

www.ebay.com

Anybody know where to heatsink this. I think the control chip on the bottom

 

[Giannis_TDM]

Laser Diode LD Driver Board PCB 4.5A for 3.5W NDB7A75 3 Modes High Low Strobe | eBay

This Laser Diode Driver PCB 4.5A Constant Current can be used to drive 3.5W NDB7A75. This is a 4.5 Amp laser diode driver with 3 modes, high, low, and strobe. Most people will use 2 Lithium ion IMR or INR batteries at 8.4 volts.

www.ebay.com

Anybody know where to heatsink this. I think the control chip on the bottom

Both of the SOP-8 are fets, Seems like a CV SMPS with current sense using an opamp, not a good one considering the price first Fet that goes to b- is just there for reverse pol protection, One of the SOP23-5s is the switching controller, 90% sure its the LEDA one.

 

[Andrew124C41]

Both of the SOP-8 are fets, Seems like a CV SMPS with current sense using an opamp, not a good one considering the price first Fet that goes to b- is just there for reverse pol protection, One of the SOP23-5s is the switching controller, 90% sure its the LEDA one.

Seller said input voltage 3 to 5 V. Is that possible? 3.5 W and 4.5 amp?

I think it only puts out 3.5 amp. Just wanted to see what this is. Probably, not any good.

 

[RedCowboy]

I have several of them, mine are 3 mode and a few showed up single mode, 3.5a output and the 3 mode also has a low which is rapid pulsed like a led flashlight so you can only see it when swirling your beams spot on the wall and a slow pulsed mode intended as a strobe mode, I never heat sink any of mine and they work just fine.

-EDIT-
Supply voltage is 5.8 - 12.0v but I suggest 2 x 18650

 

[Andrew124C41]

The seller has no idea what he is selling! He thinks the input voltage is 3 to 5 volts! Do you have to heatsink the controller? There is another component on the same side which is taller which makes it harder to heatsink the controller next to it....if it needs it

 

[RedCowboy]

I don't heat sink these drivers and I have run them for at least 10 minutes continuous duty with no issues, are you building something for continuous 24/7 use ?

 

[Andrew124C41]

I don't heat sink these drivers and I have run them for at least 10 minutes continuous duty with no issues, are you building something for continuous 24/7 use ?

Heck no lol. BTW, what is that you made? I thought about taking 3 12mm modules with 44s and bunching them tightly together in an aluminum HS. Not colimsted but the beans would be close

 

[RedCowboy]

It was just for fun, I love the aesthetics of multiple beams, but knife edging is by far the best way to go, I posted a thread about multiple beams here.

 

[Andrew124C41]

It was just for fun, I love the aesthetics of multiple beams, but knife edging is by far the best way to go, I posted a thread about multiple beams here.

You did a great job as usual. I want something portable and powerful

 

[RedCowboy]

I use c-lens correction and a beam expander on all my nubm44 builds to get the useful power down range, it's a lot of fun lighting my fireworks with a laser, of course anyone doing this must do so safely.

I expect you also want it compact ?
Do you want burning strong or bright looking ?
NDB7A75 with a 4X c-lens pair or a NDG7475 and I have an anamorphic prism pair I want to try out in a compact handheld.

But it all depends on what you like, power without the pretty beam is not as much fun so I won't speak about non vis here but the stronger you want the bigger your form factor, are you talking backpack full of batteries and a cooler with a cabled rifle length head/wand or a pocket friendly unit ?

You would likely enjoy a 7A75 with a 4X c-lens pair in a 2 x 18650 size unit with a couple extra inches on the head for the optics, makes a nice point and click paper burner and fireworks igniter.

Here's an older build I have posted with a 7A75 and c-lens, is this about the size you want, it could be made a good bit smaller.

 

[Andrew124C41]

Well, I am getting over 7 W from my 44 on the maglite. I have no idea how to mount the c lenses.

BTW turns out that driver is a 3 way. HP, LP, then blink. I have it on an 07

 

[Andrew124C41]

I use c-lens correction and a beam expander on all my nubm44 builds to get the useful power down range, it's a lot of fun lighting my fireworks with a laser, of course anyone doing this must do so safely.

I expect you also want it compact ?
Do you want burning strong or bright looking ?
NDB7A75 with a 4X c-lens pair or a NDG7475 and I have an anamorphic prism pair I want to try out in a compact handheld.

But it all depends on what you like, power without the pretty beam is not as much fun so I won't speak about non vis here but the stronger you want the bigger your form factor, are you talking backpack full of batteries and a cooler with a cabled rifle length head/wand or a pocket friendly unit ?

You would likely enjoy a 7A75 with a 4X c-lens pair in a 2 x 18650 size unit with a couple extra inches on the head for the optics, makes a nice point and click paper burner and fireworks igniter.

Here's an older build I have posted with a 7A75 and c-lens, is this about the size you want, it could be made a good bit smaller.

I looked at that older thread. That is some piece of work! I mean the optics! I have no idea how you did it.

One thing I don't understand. Actually, two.

To increase power at a distance, is the lens pair necessary? I thought all that does is give you a tighter beam but I did not think it would give you that much more power.

As for the beam expander, I have two of them..the Sanwu and Jetlaser.

When you expand the beam, you get a pretty larger swath of color projected down range but decreased power.

I never found that I could get the beam spot tighter and increase down range power.

That is why I thought of this idea...

Imagine 3 12 mm copper modules held tightly together in a kind of triangle.

Cut 3 holes in an aluminum heat sink in such a way to duplicate the triangle.

Not all of each surface of the modules will touch the sink but hopefully enough to cool for a workable duty cycle.

How far apart do you think the beams would be at 15, 20, and 30 feet? One could experiment and see without the sink.

You could also put some kind of lens in front of the beam.

Maybe it would be easier to do with one of those new ~95 W diode arrays....if we could get our hands on a new, unused one.

Wouldn't you get more power from an uncorrected 95 W array than a corrected single 44?

 

[RedCowboy]

Q: Wouldn't you get more power from an uncorrected 95 W array than a corrected single 44?
A: Yes up close if you use a lens to concentrate the 95w array onto your meter but not at a distance because of the divergence, not at your meters sensor, you will still have 95w at distance but it will be spread out wider than your meters sensor.

You would be better off knife edging several beams than trying to make one of the projector arrays work at any real distance.

The blue multi mode beams diverge unevenly, the fast axis diverges much more aggressively and that is what we correct for with c-lens pairs, it's a beam expander for one axis only that you employ near your G2 lens where the beam is still small in dia. so your beam will then diverge more evenly and a spherical beam expander will yield a much better result, all the beams from the projector arrays suffer from this same issue.

Optics don't increase power just power density when you concentrate all your beam into a small spot, like holding a magnifying glass between the sun and the Earth, the magnifying glass doesn't increase the suns energy it collects what hits the lens and focuses it onto a smaller area/spot increasing the energy density per area for the area of the spot.

 

[nmbusa]

Seller said input voltage 3 to 5 V. Is that possible? 3.5 W and 4.5 amp?

I think it only puts out 3.5 amp. Just wanted to see what this is. Probably, not any good.

I got a few of these and as red says they work great,if the 3 modes dont bother ya.
I power a NUBM44 at 4.5A with 1 of these in a small host with trimmed pcb to 18x11.5mm.
as for 4.5A as its 3.5A driver playing with parallel sense resistors results in your desirable output as mosfet is good for 10A
cheers

 

[Encap]

To increase power at a distance, is the lens pair necessary? I thought all that does is give you a tighter beam but I did not think it would give you that much more power.

If you can't combine the beams all you get is multiple beams of whatever output each at whatever distance far or close apart they are over a given area. You can combine 2 beams with a PBS cube and get a higher ouiput power in a single beam.
See: https://laserpointerforums.com/threads/reference-guide-how-to-combine-lasers.77449/

 

[Andrew124C41]

If you can't combine the beams all you get is multiple beams of whatever output each at whatever distance far or close apart they are over a given area. You can combine 2 beams with a PBS cube and get a higher ouiput power in a single beam.
See: https://laserpointerforums.com/threads/reference-guide-how-to-combine-lasers.77449/

Can you make a portable unit?