I’ve found output charts for XP-E2 660nm, but can’t find anything specific for the SST-20. Are they in the same ballpark? I know neither is going to have a huge output. If anyone has other thoughts on those two, or any other deep red emitter I’d love to hear it.
I saw some triple XP-E2s for sale as well. Are the Mtn Electronic buck drivers appropriate for those? It looks like they’re not meant to go below 3v. Is there a better off the shelf driver for 5+ amps to a red light?
I haven’t looked at red in awhile but was perusing the royal blue specs recently. On the red it seems that the SST-20 is maybe a little better all around but it’s going to depend on binning from each for comparison. Derating isn’t so terrible on these but pay attention to what they state as the typical junction temperature for the specs shown (and current, of course). Here’s a direct link for the SST-20 deep red datasheet. If you don’t have it for the Cree yet those are found easily on their website although if they’ve improved the emitter and published a new sheet then you may only be able to find the most current sheet (generally the improvements are small increments, though). Tough to find out what bin you have sometimes but these get you in the ballpark. Seems like Osram had some to offer as well but I’m not sure if those were flashlight/host/heat worthy or not.
Simon has a dedicated red driver with lower output voltage…not sure of the amps. If you’re talking a single emitter I don’t know if any can handle 5A without active cooling (I could be wrong about that…maybe someone like djozz tested a red here on BLF in the past?). On the SST sheet here they list a max of 3A with a room temp 25C junction. On a white emitter we just ignore that and mostly overdrive everything. On colors you can’t push them quite as hard without drastically shortening their lifespan maybe shifting the output a little, but they aren’t wimpy. I haven’t built anything with red and the royal blues were no problem in terms of voltage or trying to drive them hard, so my input there is limited and indirect I guess. Others probably have some better experienced advice to share…at least a couple past threads on deep red, too, if you search those out.
I vaguely remember seeing the datasheets, and the sst20 deep red compares to the xp-g3, which outclasses xp-e2.
Thanks Correllux, I probably will use Simon’s 2.5A driver with a single emitter. I was mostly curious what people are using for the triple red emitters. Maybe they’re just using a linear driver and dealing with the heat.
Thanks QR! If that’s the case I’ll probably just pickup an s2 with sst-20. I kind of wanted an excuse to build something different with that same driver, but for under $20 the s2 is hard to pass up.