Cheap bare 385nm UV LED

The seller has to many LEDs in stock at the moment. But next time he has to restock he will try to get some with higher flux bin. If he can get them he will let me know.

Thanks for checking. Please keep us updated here.

I have sent 37 leds in the mail on friday.

And yesterday evening I did an output test on the led (will call it the 4th gen. LG 3535 UV led). Do not expect anything as accurate as my white light tests, my method of testing UV leds has many imperfections leading to probably large errors (method here). Errors are caused by fluorescent bleaching of the used copier paper, variation of fluorescent die in the paper, but also higher than average output drop upon warming up of UV leds. On top of that the new led has a vastly different emission angle which also will cause extra error the way the led illuminates the paper. The measured voltages however are as correct as my normal led tests.

So I was quite surprised how close this led tested to the 3rd gen. version I tested 2 years ago.

The main difference is the much lower voltage of the 4th gen. led which makes even this lowest bin more efficient than the 3rd gen. that was tested, so it can not be direct driven on a single li-ion anymore but must be regulated (i.e. by a 7135 based lineair driver). And like the 3rd gen. led the sweetspot for me is 1.5A.

I expected a low Vf at the V1 Voltage bin but this is really low. Mhh the idea to use a FET on the MELD-X Driver for the UV channel is no longer a good option. And i do not think that all the parts will fit on one PCB. Not if i want to go up to 4-4,5A on the UV channel (tripple UV) and 700mA on every other channel. This would require 20*7135 chips.

Did anybody know a source for the good “Raptor claw” 7135chips? I have a few left but they will not last long. And with more low Vf LEDs getting on the market i want to stock up a few if i can get them.

Hi Docc, if you are in contact with the seller next time, could you ask him if he would stock LEUVA33W70RL00 ? That is a led I have been eying for more than a year and is nowhere to be found: 365nm, 1000mA, 1800mW radiant power. Small chance that he will bite, but who knows? :slight_smile:

No direct drive? Thats a bummer, now i have to order extra drivers for this :cry:

Oh well no big deal. Saved enough on the dies that i can maybe get a couple nanjg’s sent over.

No problem djozz. Mail is send. And maybe we get the leds we want for a good price.
Another question is how to drive a UV tripple with this leds? And at the same time the mc-e with the same driver. Is there a better way than using 20* 7135chips?

Ps.

- Did anybody know a source for the good “Raptor claw” 7135chips? I have a few left but they will not last long. And with more low Vf LEDs getting on the market i want to stock up a few if i can get them.

  • Is there a cheap source for a 385nm filter lens? Like the ZWB2 for 365nm.

@djozz
I found this PDF and there are a few leds that i find interesting (https://www.lasercomponents.com/fileadmin/user_upload/home/Datasheets/lg/lg_uv_led_overview.pdf).
1.LEUVA33W70TL00
https://www.irtronix.com/leuva33w70tl00

But what kind of ledboard would i need for this leds?

2. LEUVK33W80TV00
https://www.irtronix.com/leuvk33w80tv00

3.LEUVA66X00TV00
http://www.irtronix.com/leuva66x00tv00

Thans for the links.

A year ago I have tried to contact Laser Components by email trying to obtain a few LG UV-leds, and they never resoonded, perhaps they were not that interested in selling just a few leds.

The irtronics link is new to me, but again no webshop, I bet that they do not want to sell just a few samples.

The LEUVA66X00TV00 has a 6060 footprint. Is there a copper DTP board available for this footprint?
And how would you drive the UV tripple? With fet and small wires to reduce the amps or would you go regulated?
I want to ask if you still have a few springs left to sell from the batch you mentioned in the Q8 thread?

I’m not aware of a 6060 dtp board.

For the triple a 7135 based driver with 12 chips, i.e. a biscotti driver from Simon with 4 extra chips.

I do have very few springs left but will keep them. Btw, I’m totally surprised that in the 3 years since I had that small batch of phosfor bronze springs made, nothing happened in China, no other phosfor bronze spring came to the market but that same tiny spring that Fasttech first started selling.

Did you still know what the batch of springs had cost? Because there is no really good spring available a GB could be interesting. The last one i was really happy with was bought from Richard. But it is not listed anymore in his shop.

They were expensive because I only had 200 made: they costed me a dollar a piece. This was my sales thread: trying to sell a few of my custom made phosfor-bronze springs

If I had 2000 made, they had costed me at least 3 times less but that was a financial risk that I did not dare to take. If I had known that it would stay the only proper spring for sale in 3 years to come, I would probably have sold all 2000 after all.

Mhh not cheap! So at the moment we only could hope that a shop will jump on this. It would be nice to have a source for good strong springs.
i am still searching for the good 7135chips. FT can not get them and i am running out of options. I need 20pcs for the MELD-X driver but only have 17-18 left.

PS.
The UV leds arrived today.

Mine arrived today, too!
Thanks!

leds received, thank you.

I still haven’t received mine yet. I keep watching the mail box… every day… hoping to see a package… Maybe today. :weary:

how about DD with FET but with a resistor glued with thermal epoyx to the host that eats up that 0.3-0.5V to get to a safe current

I got mine today! WooHoo! :smiley:

Got mine last night!

tried it with few tir lenses, the only tir that wont block uv is pmma, originally i was gonna use triple from ledil, but tall dome makes it impossible to use that lens, polycrb, lenses all block uv, so they are useless with this led, the led does fit under cute 3up (35mm) lens, and it is the only lens, that i have, that fits, somewhat focuses it. and does not block uv.

i wonder if dedoming will either fix focus situation or make it worst. will have to try that later