NUBM07E 465nm 2.9W Diode Test (Hitting 470nm+)

[Cel]

How is the divergence compared to NDG7475 or NDB7875? (With G2, 3ele, G9...)

Are those "ball" lens any good? Can they be mounted for focusing or something similar?

I see everyone talking about the power, but some people prefer good beam specs.

 

[TaterMay]

How is the divergence compared to NDG7475 or NDB7875? (With G2, 3ele, G9...)

Are those "ball" lens any good? Can they be mounted for focusing or something similar?

I see everyone talking about the power, but some people prefer good beam specs.

Those points are all covered in this thread. Some people talked about power, some about wavelength, but there is plenty of discussion about the "ball" lens and divergence throughout this thread.

Someone else correct me if I'm wrong, but divergence for this diode should be between the NDB7875 and the NDB7A75/NUBM44, right?

 

[RedCowboy]

Those points are all covered in this thread. Some people talked about power, some about wavelength, but there is plenty of discussion about the "ball" lens and divergence throughout this thread.

Someone else correct me if I'm wrong, but divergence for this diode should be between the NDB7875 and the NDB7A75/NUBM44, right?

More divergence but more powerful. There are lenses to shape the output if you want to, but even without they are more powerful.


Here is a real test result of the focused line width of a M-140, a NUBM07E, and a NUBM44 with a 3 element lens all from 14 and a half feet. Yes I was wearing socks in my basement.

 

[Alaskan]

FYI, my 07E set to 4.5 amps finally had a failure, only 250mw out now

I only had it running for about 30 seconds tonight when it happened.

 

[RedCowboy]

FYI, my 07E set to 4.5 amps finally had a failure, only 250mw out now

I only had it running for about 30 seconds tonight when it happened.

Dam I'm sorry to hear that.
I set mine at 3.5 amps and it's still strong but time will tell.
I would stay 3.75 amps or less on those because the knee is at 4.0.
I will also keep the Gball on the next one.
Yours sounds like it just went LED, that's a classic over current failure symptom.
But hey, at least that mega 520 you're building should look great and will last, it's bound to be one of the brightest looking around.

I had one of my NUBM44's drop to about 60% output, I had it at 5 amps and it's the one that DTR decanned because its window popped the first week.

I am blaming myself because the full copper back half came loose, but I would expect it to fail not weaken because I would run it until it was hot with 4 batteries in series parallel to support the longer run times and it never quit, it just weakened, It may have lost a bit before the noticeable drop but I have no LPM.
I put a new full copper back on it and only ran it off a bench top supply feeding it only 3.0 amps every day. It just continued to weaken but would not die no matter how hot it got.

Finally I tried to kill it after that by running it un heatsinked and it dimmed out pretty fast, it seemed dead, zero output, but when it cooled down it worked again.
It slowly continued to weaken as I ran it hot but heat sinked each day but it just would not die, just slowly weaken at 3.0 amps.

Finally I said F it and gave it 18 volts, that finished it dead as a door nail. It was not much good sucking down 3 amps and putting out less than a m-140 with 3 times the divergence, also it seemed like it would work better from a cold start then weaken more, that's something I have seen with m-140's as they wear out.

Yours sounds like it just went led, classis over current symptom.
Mine was strange, almost like it wore out very fast.

My other NUBM44 is running at 4.5 amps and has it's can on, so far its fine.
I'm not sure if 5 amps was too much or if going open can was a factor, these 445's have gotten pretty tough, maybe I just damaged it when the back came loose and it had a long death spiral after that.

2 things stand out as need to do's and that's not pushing past the knee and I want to run my Gball diodes with the can/Gball in place, at least for a while, I'm probably worried about nothing, but as these diodes are not cheap I'm allowed to be a little over cautious.

 

[gozert]

FYI, my 07E set to 4.5 amps finally had a failure, only 250mw out now

I only had it running for about 30 seconds tonight when it happened.

Oh damn, that sucks. I have mine running at 4A and have yet to encounter any issues. As you know, I have it sitting in a rather large heatsink so it won't get hot very easily. I was going to ask about you using the lasers in a rather high temperature environment, but considering you're in Alaska I doubt it running hot is the cause of a failure. My laser usually sits at about 18-20ºC and doesn't really get hotter that 25-30ºC unless I run it for longer than 2 minutes.

 

[RedCowboy]

Oh damn, that sucks. I have mine running at 4A and have yet to encounter any issues. As you know, I have it sitting in a rather large heatsink so it won't get hot very easily. I was going to ask about you using the lasers in a rather high temperature environment, but considering you're in Alaska I doubt it running hot is the cause of a failure. My laser usually sits at about 18-20ºC and doesn't really get hotter that 25-30ºC unless I run it for longer than 2 minutes.

Mine is running at 3.5 amps in this ridiculous monster, it's 1.25 round bar and 1/4 inch stock on all 4 sides of the box and collar.

I only run it 2 minutes until the nose is slightly warm. If it dies early I am going to have to conceder it oxygen exposure related.

 

[TaterMay]

FYI, my 07E set to 4.5 amps finally had a failure, only 250mw out now

I only had it running for about 30 seconds tonight when it happened.

Ah man, I think I might run mine at 3.8A based on this. I was going to run it at 4A, but I really don't want to take a chance with a $150 diode.

 

[DTR]

FYI, my 07E set to 4.5 amps finally had a failure, only 250mw out now

I only had it running for about 30 seconds tonight when it happened.

Oh man that sucks. The question I wonder is if the diode did not like the current or if it is because the can is removed. Did it die on a start or while running? Did it fade out or blink out?

 

[Alaskan]

I have a host which has a problem, the batteries are a bit loose inside and they kept disconnecting the power when they moved, as I pointed the pointer down they would connect, point to the sky disconnect, about four cycles of that and the beam changed, much lower output and a little split of darkness in the center of the beam which wasn't there before. I would think the driver would prevent any problem, because even though this was occurring, my thought is it isn't any different than pressing a button, or is it? I should have put more magnets inside to space the batteries more so there would be solid contact.

 

[RedCowboy]

I have a host which has a problem, the batteries are a bit loose inside and they kept disconnecting the power when they moved, as I pointed the pointer down they would connect, point to the sky disconnect, about four cycles of that and the beam changed, much lower output and a little split of darkness in the center of the beam which wasn't there before. I would think the driver would prevent any problem, because even though this was occurring, my thought is it isn't any different than pressing a button, or is it? I should have put more magnets inside to space the batteries more so there would be solid contact.

I have pulsed lasers in the past by rapidly half pressing the tail cap to make them strobe/flash and it has not been a problem.

I think the SXD drivers have a ramp up cap to slow start the diode making the full current shock less.
I am guessing here, but maybe rapidly pulsing the SXD negated the soft start afforded by the driver giving your diode the full 4.5 amps again and again like a hammer.
If that theory is right them dropping the current back to just under 4 amps would probably be a good idea.
As tail cap switches are getting cheaper I have fried a couple of them and had to retrofit a better quality button switch on my FL tube that I use on my 07E hand made housing and flickering the power set at 3.5 amps has not done any noticeable damage.
It may be one of those cases like with the 405 diodes where they will take being overdriven but only if the current it ramped up.
This is just my theory as usually the blue N brand diodes are quite robust, but maybe this wavelength is not as forgiving yet.

Update: It seems I was wrong about the slower axis being more divergent as I have been burning at 5, 10, and 15 feet with this 07E today and it focuses to a very sharp line. Yes the fast axis is twice as wide as the M-140/NDB7875 but the slow axis focuses very sharp now that I am burning/viewing it's focal point through the amber glasses.

It seems almost a sin to burn with such a gorgeous wavelength but it is quite enjoyable, it makes much faster work of my little green targets than the 7875.

3.5 amps I think is the sweet spot for these, maybe 3.75 but I would stay south of 4 amps.

 

[Alaskan]

Thanks for the update and great information. I checked the driver I was using with my 07E which failed and found it was set at about 4.4 amps when first turning on, nothing wrong with the driver but I turned it down for use with the replacement, when I can order it later.

 

[RedCowboy]

Thanks for the update and great information. I checked the driver I was using with my 07E which failed and found it was set at about 4.4 amps when first turning on, nothing wrong with the driver but I turned it down for use with the replacement, when I can order it later.

No problem, and again I am not knocking anyone's product, I know we are all glad to have them.
Thinking back to the NUBM44 thread Dutchlaser had a hell of a time adjusting his and I think DTR said afterwards that there can be some small deviation and he explained the ramp up cap.
I wanted to turn mine that I had bought set at 5.0 down to 4.5 and found the pot to be very sensitive and a bit tricky to stabilize, then after adjusting it I found that it would range from 5.5 amps with fully charged quality brand new INR cells to 4.2 amps over their discharge down to 7.1 volts under load, but after a few heating and cooling cycles it settle in.
I really can not think of anything other than that pot that could cause this, Dutchlaser had a theory on it:

Originally Posted by DutchLaser
QUOTE START:
I think the issue is heat.
Here is a crazy thought:
Is it possible that the heat from the driver is lowering the resistance in the potmeter? because the variable resistor in the potentiometer is made out of graphite. And graphite conducts electricity better when it gets hot.
I do know that the potentiometer on the driver is very sensitive when it comes to adjusting.
QUOTE END

Dtr later commented:
QUOTE START:
Yes this is correct. The SXD drivers do drift up about 200-300mA from cold start when running over 4A but then hold steady. You should not have a problem setting them as it gets to full current very quickly. Angelos had made these drivers capable of a exaggerated slow start which I had him turn off on the ones he sends me where it goes to 50% right away and then over depending on how long it is set slowly increases to full current to reduce startup shock to the diode. I think this is a residual of the feature being turned make the start as fast as possible. He can probably comment further on the specifics of it.
QUOTE END

My advise is to run your heat sinked driver into a 1 ohm test load with your selected batteries and view the current output via inductive amp meter for several heating and cooling cycles before connecting to any expensive diodes.

Again I am not attacking anyones product, I am sharing my thoughts and experiences with these drivers in an effort to help others protect their investment.

My methods could be flawed, I could be missing something, anyone with intimate knowledge of these drivers feel free to educate me, I will happily learn how I got it all wrong.

 

[Lifetime17]

Hi, mine is running at 5.0A SXD with a long ramp up G2 lens and it hits the 470.16nm mark.
i may run it about under 60 sec. never mind how much mass the sink is. here are pics of my LPM for this diode.
All my high power diodes have the SXD FULL ramp up time on them. If you plan to build a high power diode ask Angelos for the max on the ramp up feature. It saves lives and the diode doesn't get smacked hard on start up.

 

[lazeerer]

I will Clear up everything for you guys to end this.

I think you guys are not understand External op amp based drivers and how they perform on such small PCB drivers. Also The Numbers mentioned above for the offset are Way off then what you should be getting.

All External op amp bassed drivers will have some Offset current due to heat up of the driver/external amp. Its called Offset current. The op amp heating up changes the internal reference/resistance slightly inside the amp and will cause some offset.

There is also a little Lag from the heat of the main chip going to the op amp since they are not together.

When you dont use an External Op amp the Amps Inside the Chip are so small on the die that everything heats up evenly and together So you never see this offset pretty much.

The Ramp Up has very little to do with it except for a couple seconds.


The Flex Drive for example uses an external op amp "In fact the same one i use" but because it was such low current (1.5A MAX) The driver dint get as hot (And also for the flex drive it was always recommend to heatsink the 6 pin and the 5 pin"Op amp" on the bottom of the driver which is another reason you dint see the offset much because it was sinked) the offset was Under 30mA and most dint notice it.


Without heatsinking the driver at 4.5A you should only get a drift of MAX ~100mA (I get 90mA before it starts dropping in current) at the proper load of these 07E diodes before it overheats on you and goes into thermal protection.


The SXD Thermal Protection kicks in very High 105C-115C Ambient. (This is MUCH higher then the typical Chip of ~70-80C)


If you heatsink the driver properly you should only get a drift of ~50mA MAX over a 5+ minute run at ~4.5A. You should not be getting higher then that heatsinked.

Thats Only a ~<1% Error Offset. Thats Noting for 4.5A

On a 5 minute run heatsinked at 4.5A with a Load of 5V, input voltage at 8V i got an offset of ONLY 20mA and it seems to have settled right around there. Id say thats pretty stable for 4.5A

Heatsinking the SXD properly is by Heatsinking the 8 pin chip and also the 5 pin chip.

Put ONLY thermal adhesive on the 8 pin chip and on the 5 pin chip. DO NOT put thermal adhesive on the entire bottom of the driver.

The 5pin chip has a slightly lower profile then the 8 pin chip. Its about 0.25mm of space gap. So that should still be thin enough for just thermal adhesive to be used and be just as effective as using a spacer.


So this is due to the offset current that all external op amp bassed drivers will have.

You should Only be getting at 4.5A Unheatsinked ~100mA MAX offset current before the driver start dropping in current. Which happens at ~25 seconds. (UNHEATSINKED)

At 4.5A Heatsink you should only be getting ~50mA MAX offset current over a 5+ minute run. It would settle around 30mA-50mA....

That is Less then <1% offset error. Thats Nothing.

I will make a nice post later today on how to properly heatsink the SXD and for that matter any driver as well as make some videos on how stable the driver is when heatsinked correctly. Hopefully this well help you guys out.:beer:


@Lifetime17 Killer build.!

 

[RedCowboy]

Reply to Lifetime, NICE, looks like you got a freak of a diode there, on page 1 it looked like 5 watts was it, after that it was all spectral shift but no more output. Good looking build, sturdy, I'm a big fan of battle ship sturdy.

As for the SXD my heat sink was solid, my problem was after adjusting the pot, it seemed to need to heat and cool several times before it settled in.