Finally someone with a will for FET solutions 
Is there any way to put some kind of resistor on a top of a driver and where would you put it? I pot drivers so it would be nice if I could merge resistor with a driver for permanent bond :+1:
You would put the resistor anywhere in the main current path. The challenge is the heat dissipation. It will be producing between 2 and 5W depending on what current you choose (5 to 7A), and that is a lot for a small resistor so it will get very hot.
has anywhere got stock of these yet? Also does convoy do a 4040 gasket or are we stuck with reaming out the 3030 ?
EasyB,
Can it fit to 17mm diameter? Can I cut it to fit if needed? I have aluminum and copper plates as potential heat sink for resistor and when I merge everything with potting compound it will look like it is made from one piece and whole driver should act as a heatsink.
But if it generates serious heat at 5A (more than 60 celzius) that could be problem…
The extra heat is not large compared to the total heat from the LED. The risk is that if the resistor you choose is too small or not heat sinked enough it will burn up. You will have to look for resistors that will fit in your lights.
Can you link me some kind of big but no to big resistor that could be bent into 17mm diameter please. I really don’t know what to order? Pretty please… 
Use a square file, only cuts out the necessary corners.
Anyone have any leads on this chip yet? Seems impossible to find, but some people have gotten their hands on it.
I haven’t heard anything about it, but apparently they have another boost family emitter 0.5mm² named HM I think.
Okay, so the ‘boost HX’ is basically the 2mm² white flat with a 4040 footprint.
So the 1mm² white flat with 4040 footprint will probably beat it in throw (like with the 3030 sizes)?
@Jerommel
Yes. Boost line seems to take a given chip and move it up one package size/class. This probably didn’t mean much for the 1mm² chip but should for the 2mm² . Where 1mm² saw a ~10% “boost” in current handling, I would expect 15-20% for the 2mm² . This might close the gap entirely between these two. The choice between would then be based on your host/driver/runtime restrictions.
@Fat_Controller
Interestingly the If vs Vf curve maxes out at 8A (despite 6A rating)! That should mean we have a bit of overhead there I would imagine…
EDIT: Looking at the datasheet for the 1mm² (Boost HL) it appears they did the same thing. If vs Vf goes up to 4A and max rating is 3A. If overhead is proportional then the HX should be good for 12A. We’ll still just have to see if the HX ever shows up.
PS: Interesting to note as well, the HL product page notes it’s “not for new designs”. I wonder what why? Is there a successor already?
I guess vinh/skylumen found some so we will know soon enough I’m sure
Yes, Vinh and L4P have some already. .5 mm² variant is exciting news 
I could not find the Boost HX on L4P’s website. Vinh definitely has it though. He just posted a pic of it.
Well hopefully he provides some test data or can lend a fellow member with the equipment one soon. Very curious if the 4040 Boost footprint allows the 2mm² to achieve the ~5.5A/mm² like its smaller brethren. Or at least close the gap.
Speaking of which, I really wonder how much the rectangular geometry is a functional design aspect allowing the larger die to reach such high current density. Please excuse my lack of knowledge here but is there a flow of current along the surface plane of the chip? Does anyone here have expertise in this area?
No idea really, but if it was all the same, i think we would have many round die power LEDs on the market.
Oh, i thought it was more than 10 % more current for the 1mm², but it makes sense that it will do more for the 2mm²
Well circles, in general, create processing challenges in all kinds of industries. Radii are just harder to deal with than perpendicular lines (again, generally).
I’m coming at this question/idea from a uneven current distribution caused by series resistances. This is the only reason I can intuit - other than tolerance stack up on defects - that there is a decrease in peak current density as dies get larger.
I know older generation CREE leds used to use grid style current spreaders, then they turned into arrays of dots (vias?). I’m assuming those aren’t used anymore with flip chip designs, either that or they just aren’t visible anymore? I guess it’s time I learn me up on some ol’ semiconductor anatomy.