3.5W NDB7A75 445nm Laser Diode

[kaunak]

That is around what I was getting. You can see in my video at 3a. I was getting 4.84w at 4.9 volts

I think your meter is accurate. You meter registered between 1.1-1.6w for the new 520nm diodes @ 2.4A, which is well within the expected range and the same as DTR was getting with those diodes. DTR might have just tested a low-efficiency diode or something is wrong the LPM. Hard to say at this point. I thought the test that was on video was done with a 3 element lens. Those numbers would make perfect sense then

 

[ARG]

@kaunak
Diode outputs do vary greatly, also remember that most laser power meters are accurate within 5%.
At higher powers (5W) that 5% error means +/-250mW, across two meters that can be up to a 500mW difference.

The voltage difference can probably be attributed to different voltage drops in the wires.

 

[DTR]

Jordan, were you using a G-2 or 3 element lens on these tests? I have been getting 4.7-4.9W at 2.8A current using a G-2.

So the two I sent you the other day are doing 4.7W @ 2.8A? Is that a stabilized reading after 10 or so seconds or a peak reading?

On the test I did my voltage was higher and I got more power at 4a got 5.1v and 6w could it have been a rare diode or just my power supply?

My old leads used to drop 0.5V more than the nice new ones I got and I have another set that I bought that I don't use that drops nearly 2V more than these. There is a lot of variation in resistance quality with different leads out there. Yours may just have more resistance than mine.

 

[InfinitusEquitas]

Well I just had a lasergasm. Thank you for sharing the results. Looks like the day of the 5W handheld is really not that far off.

 

[Atomicrox]

Thanks for the tests!

Would you mind comparing divergence to the 638nm mits?

 

[kaunak]

@kaunak
Diode outputs do vary greatly, also remember that most laser power meters are accurate within 5%.
At higher powers (5W) that 5% error means +/-250mW, across two meters that can be up to a 500mW difference

True but that would be odd for two good-quality meters to be out by 250mW in opposite directions at 5W. Even that wouldn't explain the difference between what Rick and others got compared to DTR unless DTR just had a less efficient diode which is very possible.

 

[COMMANDR]

Binning could well account for the difference in the diodes performance.
In semiconductor device fabrication, product binning is the categorizing of finished products
based on their thermal and frequency characteristics. Many semiconductors such as CPUs,
RAM and GPUs are binned, so I bet these diodes are also subject to the same variabilities.

 

[Garoq]

So the two I sent you the other day are doing 4.7W @ 2.8A? Is that a stabilized reading after 10 or so seconds or a peak reading?

Yes, they were doing 4.8-4.9W max after a few seconds. My first diode was around 4.7W.

Still curious about the lens.

 

[Garoq]

That is around what I was getting. You can see in my video at 3a. I was getting 4.84w at 4.9 volts

Yes, we are getting very similar outputs.

 

[jayrob]

Nice testing...

Would be perfect with 2 large Li-Ion's using a 3.4 Amp X-Drive.

Just so happens that I just got some of those custom 3.4 Amp X-Drives from Angelos.

He told me that he tested the drivers, and that they will not drop out of regulation until getting to 6.4 Volts supply... Perfect!

 

[DTR]

Yes, they were doing 4.8-4.9W max after a few seconds. My first diode was around 4.7W.

Still curious about the lens.

Yep G-2.

Since your diodes are from the same batch this one this is probably a normal efficiency variation and since the diode is supposed to be 3.5W @ 3A or better based on the datasheet and this one gives 4.3W @ 3A it is still the most over spec diode that I know of. It is crazy efficient. 800mW over spec at the datasheet recommend current is the more than any other diode I am aware of and with some doing 1.3W over spec that is just insane. :drool:

To put it in perspective and if this diode is on the low end of efficency a 10% variation is also much better than what we have seen in the past. The 9mm 445's @ 2.4A average between 2.6W-3.2W from low to high which is near a 20% swing and the M140's about 1.9W-2.4W @ 1.8A which is also about 20%. More diodes will need to be tested to get a good sample base for the efficiency variation.

Sine we may not want to run these $450 diodes like we do with the $45 or $70 diodes it is nice to know we can have a 4.3W-4.9W @ 100% of manufacturer rating that will last for a very long time compared to aiming for a 3W+ 445nm from the NDB7875 driving it 150% of the manufacturer rating which can have degradation issues and will certainly have reduce life.:beer:


Another test.
Three Element

G-2

 

[grainde]

So when will we see the first dual diode 10 W handheld... Great work Jordan! :beer:

 

[CDBEAM777]

So when will we see the first dual diode 10 W handheld... Great work Jordan! :beer:

GO LARGE=========> OR, GO HOME !!

See drawing below......

You will see it when the module price drops from the CLOUDS !!!

Then I will build it !! Design based on the Dragon's Head platform.
To me...it looks like the Blue needs optical correction 4 sure.....and while
we are at it....might as well do the Green.

Options; Blue+Blue, Green+Green....or Blue+Green ????

With the Blue+Green option...Control function for:
Blue only, Green only....or Blue + Green = Teal

Eh....Ahhh...yes...the Blue + Green would only be 6+ watts......and optics have their limits....BUT....SOMEONE WILL BUILD IT.......of that you can be sure !!!!

Lite'em Up CDBEAM=======>

 

[IWIRE]

Nice testing...

Would be perfect with 2 large Li-Ion's using a 3.4 Amp X-Drive.

Just so happens that I just got some of those custom 3.4 Amp X-Drives from Angelos.

He told me that he tested the drivers, and that they will not drop out of regulation until getting to 6.4 Volts supply... Perfect!

Funny you should say that. That's what I'm running in mine. Xdrive set to 3.4 and two 26650`s :beer: Works great. My lpm is supposed to be in town. Not sure if it will show up today or Monday. I'll add the results to my build thread when it shows up. I have 1 more 3.5w diode. I'm going to push this one a little harder and see what I can get. Either it will blow or it will go.
Got my lpm. Driver at 3.4a I'm getting 4.3w with G2 and 3.5w with three element. Slipped in a quick test while planting flowers

Started my second 3.5w build running a boost drive set to 3.8a. Not sure how well the single Panasonic 18650 will hold up. Supposedly it is good for 10a. With the output set to 3.8a I'm showing 6.2a on the input. Going to double up on the input wires. I'll let you know if it blows or goes. Putting it in a host I got from DTR. It had a bunch of room for heatsinking. As always it's a mixed up bunch of pieces. I'm expecting the clicky switch to just melt down.

 

[CHP]

DTR,

Awesome work - thanks for sharing.

I'm trying to gage the power density between the NDB7A75 and the NDB7875. For example, if I focus both lasers at 20 feet which one produces the highest power density (watts/area) or do they both produce the same power density?

 

[andyman]

So what drivers are you folks running this with to get 5w output?