XHP-35

Well… ya got a point there! :bigsmile:

After reading the specs on this chip it look doable. Do we have any electrical engineers out there that could design a 17mm board for this. A single cell XHP35 running 1800 lumens in a P60 dropin would give throw much closer to the XM-L led as apposed to the MT-G2 and still be more efficient than either. This would also be the same for any single cell light, keeping them still in the EDC realm. I mod a lot of lights but I tend to destroy many in the process. It’s too complex for my skills. Anyone want to take up the challenge as I believe this type of driver would also give practicability too 9v MT-G2’s, 12v XHP-50’s and 70’s. I believe high drain 18650’s and 26650’s could carry the loads.

As I understand it you wouldn’t even need high drain 18650s. Assuming 80% efficiency your looking at around 4-5A at the battery end.
I’m going to have a go at it. My step fathers an electronics engineer which helps a little but I’m still a little over my depth so time to learn a thing or two. I have a CNC router which I can prototype on.

I just received 4 of the XHP-35’s in my grubby little paws. They look awesome! Exactly like the XP-L HI but with a larger phosphor fooprint on the substrate. (Exactly used in loose terminology at first naked eye appearance)

I’ll get a couple of macro images and see how they look. :wink:

i got the LD-2 and noctigon today…

now i have to play and decide if I hook it up with the seanna or a 100mm Aspheric :wink:

where did you bought them? price?

Mouser just got some in. Don’t know if Mouser Spain has em or not. My invoice doesn’t show price, not sure I want to look and be reminded… :wink:

Boost drivers. We need boost drivers to run these from a single cell. Or even better, high-amp boost drivers to run several of these in parallel from a few cells in parallel.

Who is still active who knows how to design circuits? :slight_smile:

On it. See here:

I will be copying a Ti reference desgin with a couple of slight modifications. Creating a single mode driver with over 90% efficency using the chip I pointed out (in the original post Tex linked to) up to 30W boost off a single Li-ion with output up to ~13V seems very simple… I haven’t actually built anything yet (still waiting on parts) but implementing the modes and squeezing it onto a 17m board is going to be the hard bit. I’ll post up a couple of schematics for the electrical engineers out there to review before I start prototyping.

If it has a microcontroller and a PWM-capable switching chip like the usual FET or 7135, the modes and such should be easy. If it doesn’t have those though, it’ll probably end up being very limited.

Glad to see two on board now. I’m a bit old fashion, but picture a P60 dropin running 15 watts and putting out 1800 Lumen. Right now it takes that much for an XM-L2 to do 1250-1300? It’s just so much more efficient even with only 90% boost efficiency. We also have new more heat bleeding designs/host. Don’t discount the possibilities; XHP-35,50,70’s and MT-G2 in EDC size lights. Picture for example the Convoy or Shadow host. Strange thought but it’s getting to the point where we can’t hot-rod the led past specs as much cause we can’t bleed out the heat fast enough. It’s looking like we are getting to the point of small size, good run time, and a ton of light without too much compromise. I’m not an engineer but I would encourage all of you out there that are to give this boost design some of you time.

Mmm. I was thinking a digital potentiometer but a FET sounds better / smaller. I’m still trying to fit in on a single layer at this stage so am thinking of adding legs to a 3mm thick inductor and sitting it on top of the other components. Provided those components are less then 2mm high it should just fit inside a P60 pill.

first tests with XHP35 HI soldered to noctigon, driven from a LD-2 powered from 4 cells are bright… 8)

next step: build a setup to play with Seanna and aspheric (and courui reflector)

How hard could it be to modify a SRK FET driver to run on 12v? If on board regulation of the components other than the FET could be done, it would be rather simple, right?
Something similar, maybe a little more sophisticated, to the Zener mod.

M4D M4X, how many Amps did you set up the LD2 for?

led4power set it to 2.5A

Wonderful! Now I have to scramble through the thread and find the formula for figuring out that sense resistor… :stuck_out_tongue:

Has anyone done current vs. lumen output tests on this led yet? Can’t seem to find any, and would love to see how this emitter performs when overdriven.

Thanks!

unfortunately i have no bench power supply :frowning:

Cree is it so far on the current vs. lumen output chart and they stop at 1.05 amps. Some how I think this one doesn’t need that much extra oomph. If charts are to be believed it’s up to 1833 lumens at only 13.5 watts for the high density. Flat dome (high intensity) being 1483 lumens at the same wattage.