LED spec plots

I took a look at the data sheets, gathered some data (mostly by carefulla reading the plots) of some LEDs and made some plots for comparison.

The data is at 25°C, as given in the data sheets, so thermal sag is not accounted for.

As this is a bit crowded, here's a 'flux per current' plot:

And of course the efficacy (flux per power):


Those are interesting thanks. The SST LEDs are really a triumph of brute force over efficiency at least in their ability to take more and more current.

Thanks for putting that together. It's hard to find numbers that fairly compare the LED's, so the graphs really help out. In the first graph everything stays pretty tight though. Also surprising how different the P7 and MC-E are from each other since they seem kind of like different flavors of the same thing.

Probably because Cree don't sell their best bin MC-E dies to SSC.

P7 vs. MCE: That's only because of the different binning scheme (all at 2.8A):

P7 C-bin: 700-800 lm
MC-E M: 749-854 lm
P7 D-bin: 800-900 lm
MC-E N: 854-957 lm

Thanks, very nice. Man... for the money, the XM-L just destroys. But those SSTs both have really amazing power handling without much loss of efficacy (traded for battery life hehehe). Truely amazing actually, compared to the lowered power LEDs.

I'm a bit surprised at how fast the R2 loses its lunch too. Now I can finally just ignore anyone who talks about driving an R2 with "a proper driver" and it keeping up with anything today.

Thanks for the graphs. They are clear and informative.

Just copied them to my local FAQ.

Thanks for the graphs really interesting to see how xml compares to the rest

Blame you, now I have to order even more XM-L for my upgrades.

At least I can justify it with "enviromentally friendly" :bigsmile:

Fantastic graphs....but now I realized even more that I need an SST-90 torch, grrr....

Thanks Doc,

It would be interesting to compare the SST-50 and XM-L (highest bin for both) in well heat sinked flashlight hosts (to reflect thermal sag), to find out at what current they both reach the same lm. Following the line on your graph, it would appear to happen around 3.6A (without thermal sag). With thermal sag, I wonder if the XM-L would do better up to 5A. Sure, its out of spec but they seem to survive at this level. All very interesting...