Nah, that’s nowhere near possible I think. I believe 150-200mA will be kinda pushing it for the puny 5mm body.
Where can I find these? Beware that these “100ma” leds might actually be rated at 20ma. Sure, it can run at 100ma without blowing up, but many of these are woefully inefficient at this current. You might as well run 70ma on Nichia’s GS rather than pushing 100ma on this.
I learned this the hard way when I tried to source from Alibaba the first time.
I also share the suspicion that 100 Ebay milliamps work the same way 5000 Ebay lumens work.
That said, the Yuji’s tested stable at 50mA for 24 hours when Djozz tested them, and didn’t see output start declining until 90mA. Mine started to thermally runaway about 160mA.
If a 5mm LED is well made, it can take the heat for at least a little bit.
Nah, 1/2 watt 5mm LEDs have been a thing for a long time. They are actually rated at 100mA @ 3.3V usually, so true rating is 1/3 watt, but they are called 1/2 watt and have been common stuff for years. However, they are low CRI. For a high CRI version, the Nichia GS, rated at 70mA is probably just right (considering that level of technology, which is over a decade old now)
Here is a listing on eBay. I was mis-remembering the price. They are more than “a few bux” for a hundred. Sorry about that. But, they do exist and have for years.
I’ve bought from this seller before. They are a long-time seller at eBay and very trustworthy.
Yeah, I saw that being around for quite some time and its indeed not a “few buck”. Has someone tried to compare that to Nichia GS?
Nichia GS delivers 130lm/w at 70ma. Sold at very similar price. I wonder about the efficiency of that thing.
Nah, that’s nowhere near possible I think. I believe 150-200mA will be kinda pushing it for the puny 5mm body.
I don’t want to litter this thread too much. But I guess keeping it bumped up couldn’t hurt, right? :innocent:
Anyway, I just wanted to say that I don’t believe the size of the LEDs is the consideration. For instance, there are CREE XQ-E that are rated up to 1A and are only 1.6mm x 1.6mm square. Perhaps the clear plastic that these cheap LEDs are made from can’t stand too much heat. But even that can be upgraded to a new/better material if some manufacturer really wanted to do so. The real problem is that they don’t want to. This is inherently old technology that the manufacturers believe isn’t worth upgrading, unfortunately. I think new uses for this form factor will spring up almost immediately if someone is brave enough to come out with an improved, higher power version in the 5mm and 3mm package. Like I said above, I’d buy at least 100pcs of each size for my own testing right away, as long as the price is reasonable, and would probably end up buying a lot more in the future, if they turned out to be as good as I think they would be. Globally, I’m almost certain that usage could be in the tens of millions in each size.
Yeah, I saw that being around for quite some time and its indeed not a “few buck”. Has someone tried to compare that to Nichia GS?
Nichia GS delivers 130lm/w at 70ma. Sold at very similar price. I wonder about the efficiency of that thing.
I think usually the 1/2 watt LEDs are rated at 80 lm/w at 100mA. So, a lot less efficiency, because they’re super cheap. But still not a lot worse in actual output, because they are rated to higher input current.
Anyway, I just wanted to say that I don’t believe the size of the LEDs is the consideration. For instance, there are CREE XQ-E that are rated up to 1A and are only 1.6mm x 1.6mm square. Perhaps the clear plastic that these cheap LEDs are made from can’t stand too much heat. But even that can be upgraded to a new/better material if some manufacturer really wanted to do so. The real problem is that they don’t want to. This is inherently old technology that the manufacturers believe isn’t worth upgrading, unfortunately. I think new uses for this form factor will spring up almost immediately if someone is brave enough to come out with an improved, higher power version in the 5mm and 3mm package. Like I said above, I’d buy at least 100pcs of each size for my own testing right away, as long as the price is reasonable, and would probably end up buying a lot more in the future, if they turned out to be as good as I think they would be. Globally, I’m almost certain that usage could be in the tens of millions in each size.
How LED succeeds/fails to deliver good performance or have long life time is more to do with the heat dissipation. Epoxy quality contributes very little in thermal performance compared to the substrate (although Epoxy staining due to heat is an another can of worms to open). XQ-E and most other SMD LEDs are soldered directly to the MCPCB which enjoys far less thermal resistance compared to the dinky little cathode leads of the thru-hole 5mm LEDs. That’s also why DTP boards are highly coveted here so as to wring out the last ounce of the extra lumens from the emitters.
And then how to improve the situaion? Use more efficient, bigger chip rated for higher current should be a good start. More efficient chip equals less heat produced at the same power, this less heat in turns reduce the thermal density, and thus less performance degradation. And as one of the CPF member has mentioned, the material used in the cathode lead itself. Copper would be superior compared to steel due to thermal conductivity. In addition, the half-watt LED you have do have enlarged cathode leads, and thus result in better heat dissipation.
Of course, there is quite a ceiling of what 5mm LED thru-hole construction can do, and then cost vs. diminishing returns.
In my Astrolux keychain lights there is a bit different 5mm led than usual: it has way thicker leads than normal, I’m sure that is to make them run at more power. But that also depends on where those leads are soldered, a nice copper pour on the pcb helps getting the heat further away.
But it still is a 5mm led, not a power led.
Update: the 3400k 5mm LED should be arriving at the doorstep today or tomorrow. Stay tuned for the unboxing, beamshot, and WTS thread.
OK - missed this thread somehow- but am in it now — sign me up for 8 hosts.
an amber (590nm)
This.
As I understand, the C01 may come back at some point but not now, and only if the right 5mm led is found, Barry talked about a 3000 pieces production run to make it feasable.
The most likely scenario I think for the host version is that it is blend in in that 3000pcs production run.
But keep the list going, it can not do any harm to let Sofirn know that some demand is there, even if it is not thousands or even not a mere hundred
I don’t know the turn-over of Sofirn, but 3,000 lights sounds like quite a bummer for me.
Does anybody know if there are vampire-drivers for sale? Or budget lights with such drivers?
Not exclusively talking about modifying an AAA light, even more drawn towards an AA light.
Lightbringer mentioned such a light, but I would like it to be shipped to Europe.
Last week my brother in Canada bought me a Gerber, but I’ll be da if I take that light apart.
I have a few QX5252f left. Does that count?
I have a few QX5252f left. Does that count?
Yes, that counts. But most of all because you gave me an indication of where to look for it.
And I found this LINK
That looks like a really good beam, how is the tint? Not too yellow?