505nm and 480nm diode RESULTS

[paul1598419]

Paul, quick heads up, the diode I get from Newgazer has the same pinout as stated on the data sheet posted with their ebay listing. Which is case positive.
So it is NOT the same pinout as the 473nm diodes.

WHAT?! That was not what I was told. I have them here right now, but haven't started measuring yet. If you are correct, you may have saved me the loss of a diode. To be specific, can you just give me the pin out diagram for this diode? :thanks:

Didn't mine make it to 480.2nm paul? That is what was on your sticker

Yeah, whatever I wrote on the sticker is correct. I just remember one being 480nm. Did I post 478nm. My mistake. Sorry. It has been a very long few days for me and lack of sleep is catching up.

 

[Mattronium]

WHAT?! That was not what I was told. I have them here right now, but haven't started measuring yet. If you are correct, you may have saved me the loss of a diode. To be specific, can you just give me the pin out diagram for this diode? :thanks:

The pinout is the same as the PLT5 515 so it is this. I can confirm that this is the right pinout for because this is the way I have my diode running right now.

For the ebay listing I think the first image sketch is from the front instead of the back.
ebay datasheet


I actually first tested the diode using the pinout that Zach posted in the first post of this thread but it didn't light, so I tried the other pinout and it worked! I was surprised that it did not blow the diode when I used the wrong polarity, but I suspect that the photo diode may have provided some reverse polarity protection.

Paul, are the diodes that you have from Newgazer?

I have got a cr2 keychain kit from jayrob for my 480nm build i am just not sure of what current to set the driver at that will be safe for the host.

I'd also consider how long you might keep the laser on. For a small build such a a key chain one I would guess that the laser would get too hot in about a minute, maybe more maybe less. If you don't plan to keep the laser on for long periods that's fine, but its just something to consider.
I was originally planning to make a pen build with both the 473nm and 505nm but since I want to run them at rated current of slightly above I chose to use a build that has more heatsinking. I might still make a pen build but I will likely run them under 100mA.

 

[paul1598419]

Yes, they are the same as the ones from Techhood, Existotem and Newgazer. But, think you have a pin out wrong in your diagram if the one in the spec sheet is correct. The one you have marked as "not used" is the cathode.

I see you said the diagram is from the top side. Which one did you use? I may have to figure this out for myself.

 

[Mattronium]

Yes, they are the same as the ones from Techhood, Existotem and Newgazer. But, think you have a pin out wrong in your diagram if the one in the spec sheet is correct. The one you have marked as "not used" is the cathode.

I see you said the diagram is from the top side. Which one did you use? I may have to figure this out for myself.

I used the first pinout, the one I took from DTR.
The case pin is the Anode (+) and the "top" pin was the cathode (-).




So here is the data.

Diode: SB1573N91
Pinout: posted above in post #450.
Wavelength: 503nm +/- 1nm.
λ vs. I: 0.1nm/mA

At 120mA I compared it to my argon ion and get an estimate of 503nm +/- 1nm.
The Wavelength vs Current graph is quite boring as it is just an increase in wavelength of 0.1nm for every 10mA increase (0.01nm/mA). And that relationship is consistent throughout the duration of my test from 70mA to 160mA.

 

[ultimatekaiser]

I used the first pinout, the one I took from DTR.
The case pin is the Anode (+) and the "top" pin was the cathode (-).




So here is the data.

Diode: SB1573N91
Pinout: posted above in post #450.
Wavelength: 503nm +/- 1nm.
λ vs. I: 0.1nm/mA

At 120mA I compared it to my argon ion and get an estimate of 503nm +/- 1nm.
The Wavelength vs Current graph is quite boring, it basically is just an increase in wavelength of 0.1nm for every 10mA increase (0.01nm/mA). And that relationship is consistent from 70mA to 160mA which is a far as I wanted to test.

That sounds like about what I would expect if its from a cold start

 

[paul1598419]

Thanks. You saved me a bunch of heart ache, as these are not my diodes. I was told they are the same as the SB1473N91s. That probably would hurt the diode, but would have me scrambling around to try to find the correct pin out.

 

[Atomicrox]

Let me see if I got this correctly - two different batches have different pin outs?

 

[paul1598419]

Yep. But, that's not all that different about these diodes. As the threshold is over taken the spectrum is a haystack waveform, not a peak. As the current is increased to lasing they become a nice peak as would be expected in the center of the wavelength. The first one was 502.4nm at ~30 mA and the second was 503.2nm at ~30 mA. These seem to get very hot very fast if not pressed into anything and the wavelength increases a couple of nm when the current is increased to ~70 mA. Couldn't get an accurate reading as I didn't want it there long enough to measure it. I tested it against a good 532nm and it was right on the money.

Funny thing about these LaserLands 5 mW pointers that everyone has been getting lately. Mine tested 510.8nm and stayed there for at least a minute, then started to rise slowly.

 

[ZRaffleticket]

Bad news. Either the 480 blew, my battery blew, or my driver blew.

All three are possible, and I don't have anything to test them up where I am right now until Friday evening.

__

Symptoms:

• Currently, it makes no light, none at all. Zip. Nada.
• When it first happened, it was on for ~2 minutes for taking pics. Then suddenly just shut off. About 10 minutes later, it worked just fine again from all I could tell, and then I resumed taking pictures as cautiously as I could... and same thing after 30 seconds or so of constant on. That was 2 hours ago.
• When I turn it on, the driver does not get warm at all.

Does this seem more like a diode or driver fault, or just not enough info?

I'm inclined to blame the driver as it wasn't heatsinked very well (some thermal paste pressed onto the inner wall of the host I have), and moreso that the diode is not LED'd -- it was back to life for 20 minutes or so with no sign of degradation on the spot.

My battery is also not anything special, an INTSUN '3400mAh' I've had for who knows how long.


Gonna try powering it on again in the morning unless I'm advised against it. Won't try again tonight unless you guys have suggestions.

 

[paul1598419]

You've got the Nano Boost driver, Right? My first guess would be the battery. I don't know how one would heat sink this driver as it is populated on both sides of the board and the chip is tiny. If it isn't the Nano Boost, then I still would eliminate the battery first. Then I'd carefully dissemble it and check the driver and if it is okay, then the diode. God, not the diode!?

 

[ZRaffleticket]

Yeah, nano boost @275mA. Heatsinking was not too much of an option. But at 275mA I wouldn't expect it to get nuclear level hot, but I'd expect to at least see it get warm if it were running. I dunno.

It's in a 2x 18650 host, however I have one dummy cell in place. Dummy cell is probably OK as I still got no light when connecting the battery to the threads via paper clip.... I think I know somebody at work with a vape pen... some of those take 18650's, I'll ask him if his does and if he can test out my battery. And maybe even try his in this.

Would a diode even be likely to die in such a way that it wouldn't let any current through it?

 

[paul1598419]

Sure. It's a diode. They can short or open or in the case of an LD become an LED. Of course you know to limit the input voltage to one Li-ion battery. Not two.

 

[ZRaffleticket]

Just woke up for the day. Screwed the end cap on, pressed the power button aaaanndddd... LIGHT! So it's NOT the diode. Thank GOD.

 

[CurtisOliver]

Great news Zraffleticket.
I'm glad you didn't lose the diode. :beer:

 

[ZRaffleticket]

As am I... I'm really hopeful it's just my battery that is crap. Cause I have another 8 18650's to swap with when I'm home.

Also, burned my morning toast. Oops?

 

[CurtisOliver]

I'd rather burn my toast than my laser diode any day!
Yes, definitely test your battery. Also double check the driver to make sure there is no problem with it.

Such a lovely colour that wavelength.