MrNaz
Enlightened
I've been told that the XP-E LEDs can only take up to 700mA of current? Assuming I have very good heat sinking, is it really true that an R2 binned XP-E LED can not be driven up to 1A?
XP-E - Maximum current?
- Thread starter MrNaz
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LukeA
Flashlight Enthusiast
XP-Es can't be driven at 1A in the same way XR-Es can't be driven at 1400mA. 
I would stay within the absolute maximum rating of the device as given on its data sheet. The rating is determined by the engineers who developed the device.
Although you may hear of many people exceeding the rating here, It is best to stay well within the max current rating. For very intermittent use, such as in a flashlight, you can run at max rated current if heat sinking is good.
Although you may hear of many people exceeding the rating here, It is best to stay well within the max current rating. For very intermittent use, such as in a flashlight, you can run at max rated current if heat sinking is good.
Sgt. LED
Flashaholic
So yeah an XP-E will survive 1A if you do a good heatsinking job.
Oh sure it won't live the full 50,000 hours or whatever they say it will at 700mA but the next new super LED will be out before it dies anyway.
Take the risk.
Oh sure it won't live the full 50,000 hours or whatever they say it will at 700mA but the next new super LED will be out before it dies anyway.
Take the risk.
+1 At the price and availability I know I would gamble.:devil:
MrNaz
Enlightened
Believe you me, this is one application where heat sinking will not be an issue. The MCPCBs will be mounted directly onto a _huge_ aluminium heat sink that will be immersed in the ocean. Thermal mating will be done with Arctic Silver 5, adhesion will be achieved with Arctic Silver Epoxy.
This is about as close to the ideal thermal situation as you can get. Under these conditions, what would the XP-E say about 1.4A? Is that going too high? How high can I reasonably go while retaining a reasonably long lifespan?
bigchelis
Flashlight Enthusiast
Nailbender made me a 1D Mag XP-E with a 1.4A driver it was about 168 lumens out the front with an IMR 18650 cell.
I sent it back to Nailbender and he put a 1A driver. I now make 186 out the front lumens with the same exact LED, UCL, 1D Mag, and IMR cell. So, more is not always more lumens; it is however more watts of power and in my case less efficient.
ergotelis
Enlightened
I have a XP-E with very good heatsinking(P7 heatsink for mag mod) and it has already run for numerous hours at 1,05amp.Superb performance and Really no problem!
old4570
Flashlight Enthusiast
Cheap enough !
I have a Q5 XPE on order , and I already have a R2 ..
I have a 1A buck boost driver Im going to swap in shortly , will see how it goes .
Q5 will go into a maglite ..
I have a Q5 XPE on order , and I already have a R2 ..
I have a 1A buck boost driver Im going to swap in shortly , will see how it goes .
Q5 will go into a maglite ..
Illum
Flashaholic
ergotelis
Enlightened
If you use it in a maglite, better but a KD alu smo reflector, it does produce better quality beam.Stock mag reflector will still work, but it will not be that good. Also, be careful to make a perfect centering. Even 0,1mm is noticeable in XP-E. The quality of the beam is much dependent on how well you center the led.
I have yet to do extensive testing of the XP-E but I can tell you that 1A with the heatsinking you are talking about is no problem what so ever. Don't mind the nay sayers. If you want to get to 1400mA that too is no problem but you will need to ditch the MCPCB. Instead solder the XP-E to a piece of copper to extract the heat from the die as fast as you can. From there it can be business as usual.
bshanahan14rulz
Flashlight Enthusiast
at that die size you better have the heatsink on ice!
XR-E has the same sized die as the XP-E. Difference is XR-E is on a SiC Diode/substrate, enhancing its thermal properties.
