picard
Flashlight Enthusiast
- Joined
- Dec 31, 2004
- Messages
- 1,298
what's the difference between XML vs XML2 ?
Is there big difference?
does XML2 have tighter spot ?
Is there big difference?
does XML2 have tighter spot ?
When do u guys think XML3 will come out? XML4? How fast do u see these LEDs evolving, maybe 1 level of improvement per year? I'm shocked that NEW lights are still coming out with XML U2 that's 2 bins back from the current best.
I hope that the voltage requirements and drivers of XMLs stay compatible down thru the years because I'd really like to be able to simply swap out my LEDs on my custom lights as they improve. I have really nice custom hosts (all with XML2)
So, does it generate the same amount of heat at the same lumen value?
I'm pretty satisfied with my mods, but the #1 reason i will continue to upgrade the LEDs if I can will be for the improved light to heat ratio, the ideal goal being the point where they can run continuously without over heating. Like the SolarStorm that we have how great would it be for that to handle the heat continuously?The way I see it, just get the light that does what you need it to NOW. If its working for you, you're done.
A few points that are just blatantly wrong here. Cree has always used SiC wafers for their LEDs. XM-L2 is just the 3rd gen SiC product, but nothing fundamentally different on that front. Also, the bond wires are still there, in fact instead of 3 of them there are now only 2 which is the probable reason for the Vf of the XM-L2 being higher. What was removed were the current spreaders on the top of the chip and went to a new FC style.Ok here are the improvements...
-Die shrink of around 10%
-Die change to SiC (new process beginning with the XB-D)
-Binning at 85 degrees celsius(used to be 25 degrees)
-Removal of bond wires (so we can drive it to 6A without the wires melting:devil:
-Efficiency increase of 10% (at 85C)
-Substantial cost reductions (half the lumen per dollar cost)
-Longer L70 lifetime
-And dome is easier to remove...
I think it's a good upgrade.
As long as you are using constant current drivers then it shouldn't matter a damn, unless for some bizarre reason the Vf jumps massively. Most are decreasing substantially, which just means you'll run with the same current for longer before the driver gets out of regulation.I hope that the voltage requirements and drivers of XMLs stay compatible down thru the years because I'd really like to be able to simply swap out my LEDs on my custom lights as they improve.
There is no spec; this is purely through people's experimentation, you'll find here that we see max limits as a challenge rather than a rule Note that you need seriosly good thermal dissipation to do this kind of thing. Also the spec sheets are written with a mind of reaching thousands of hours runtime; most here will never run a flashlight anywhere near that long, so can afford to push the LED further than specced.The spec sheets say 3000mA max current. Where did you find the 6A spec?
Good manufacturers of anything ALWAYs intentionally underrate their products, i.e. McClickys rated for 3A can take around 8A before melting, hard disks with MTBF of 1 million hours can almost always take more, a lift rated for 15 people can definitely take 50 or more before snapping:devil:. The 3A rating is just the conservative suggestion made by Cree for safe operation over tens of thousands of hours, the lumen increase after that is almost linear until 5A, which means that it can take a heck of a lot more.The spec sheets say 3000mA max current. Where did you find the 6A spec?