A buck driver is always possible, but doesn’t always make sense. Most stock single-cell lights with 3V LED (XM-L2 for exmaple) have a buck driver. A lower VF means that the output stays constant for higher percentage of the runtime and the average current pulled from the battery is lower. So the lower the Vf, the more sense a buck driver makes.
why use this led in 1000 lumen light, i mean, if you want 1000 lumen, go with xpl-hi,hd, xm-l2, or even xp-g3, and it’s also easier to reflow the led on MCPCB
if i use this led, i will push it over 1800, close to 2000 lumen(or even higher)
LEDs are more efficient when they are driven softly (look at the slope of the graph in the OP). So to acheive 1000Lm, a “2000Lm” LED driven at 50% will be more efficient than a 1000Lm LED driven at 100%.
Djozz, ylu know this was bound to come…please do the Q8 with these?
For me newbie it is kind of mixed.
On the one hand lots of lumens, on the other driver burning off volts. (And end Ferry Mingele mode )
If these are a good Q8 candidate, we really should have the XML pad ledboard redesigned to have pads for this as well.
XML and XHP70 would not fit, but these small pads would.
Hmm, ok, I will mod a Q8 with these, but I may wait for the new ones to do that. But mind that the stock light puts out 5000 lumen at 20A, and with Luxeon Z’s it is 8000 lumen at 36A, it will get kind of way too hot.
Thanks for the test djozz. Need to get you some samples of XP-L2. I’d donate to the cause. Impressive that the 4000k Luxeon V has almost identical output to a 6500k SST-40, and at a lower voltage to boot. Tint looks wonderful too! Can’t wait for some high CRI and more color temps.
How much does a custom run of DTP copper boards usually cost?
I just posted over on RMMs thread to see if he has any plans to stock the Luxeon V and perhaps even get some custom DTP boards made up for it. He has his MTN Quad boards which are top notch, so if he did a Luxeon V board I would be in for quite a few. A triple or quad Luxeon V board would be really interesting as well.
:+1: PM sent. I will do a new Luxeon V test on this boards and am really curious how much different it is. My guess: slightly better performance but way easier reflow!!
Have you tried a Luxeon V in a flashlight yet and if so, what is your experience?