# Difference in these high power LEDs in LAYMAN terms



## Dioda (Dec 21, 2017)

Can someone please provide basic, layman, top level characteristics and differences in these LEDs? I mean general stuff, like usual max output in lumens, ideal use for which type of flashlight - better for flooder or throwers etc. Im doing my research, but did not find much yet with focus on real life use.

XP-L HI - In my understanding has small chip (or how is the LED core itself called), has no dome, therefore ideal for throwers, output usually to max 1000 lumens

XHP 70 - lumen monster, comes with dome by default, needs big reflector for decent throw

XHP 50 - same as above, less max lumens

XHP 35 HI - no dome, Im very interesting in the XHP series, assuming this particular type will be good for 1600+ lumens throwers, similar to XPL HI

XHP 35 HD - comes with dome, It needs big reflector for good throw

Im considering a custom build of a powerful medium sized thrower based on one of these budget hosts, but not sure about which emitter will be the best for reflector approx. 4 cm in diameter.

Thanks!


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## The_Driver (Dec 21, 2017)

The emitters all have different sized dies (the yellow area of the LED where the light in generated). The size of the hotspot of a given flashlight corresponds directly with the size of the LED die.



XP-L HI: 3,5mm^2 (3.5 square millimeters)
XP-G2/3: 4mm2
XHP-35 HI: 6mm^2
XP-L(2): 7mm^2
XHP-35 HD: 12mm^2 (the dome usually doubles the apparant size of the Die and halves the luminance => throw)
XHP-50: 16mm^2
XHP-70: 28mm^2

The larger LEDs are brighter (for a given power density), but throw less. 

The XHP-35 HI is a very good option for a bright thrower. You can get up to 2500 otf Lumens. It requires 12-14V though (or a boost driver).


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## Dioda (Dec 22, 2017)

This is precisely the kind of info im looking for!!! 

So my next assumption is that although the XHP 35 HI doesnt have the smallest die size, it still makes a very good choice because throw potential due to no dome and lumen pumping in the 2000+ range. I also believe this would work well with a smooth 4 cm reflector. Can you please provide more info on suitable well designed driver (and if needed the boost circuit) and possibly where to get from? I have soldering skills, but currently still investigating the ideal components. My goal would be a self made 2000+ lumen thrower similar to Acebeam L16. As host I would consider the cheap Convoy C8, but im open to suggestions.


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## The_Driver (Dec 22, 2017)

Please always consider the power consumption. 2000 otf Lumens from an XHP-35 HI requires a lot of power (here you can find test data). A Convoy C8 would overheat quickly with this much heat.

A suitable boost driver for a single Li-Ion is the H2-C from Kaidomain. Please take into account the diameter (22mm) though. It might be too large for the light. Test data on the ouput power and efficiency of this driver can be found here. With only one cell you wont get near 1000 Lumens. With two cells in series you will get close. 

A more powerful driver is being worked on in the BLF Forum here. It will allow you to drive the XHP-35 HI with the maximum current that the LED will tolerate from a single cell and it will be available on a 17mm PCB. It's quite amazing actually.


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## Dioda (Dec 22, 2017)

Thanks for your input. Im not in a hurry, so i will do my research first. There is the UTorch UT02 available on the budget side, which has the XHP 35 Hi inside. But as it pumps out only 1300 lumens max, im assuming it is underdriven, what is your opinion on this one? And can you perhaps recommend another similar format host apart from C8?


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## The_Driver (Dec 22, 2017)

Dioda said:


> Thanks for your input. Im not in a hurry, so i will do my research first. There is the UTorch UT02 available on the budget side, which has the XHP 35 Hi inside. But as it pumps out only 1300 lumens max, im assuming it is underdriven, what is your opinion on this one? And can you perhaps recommend another similar format host apart from C8?



How long do you need maximum power at a time?

The Utorch will run for around 2min before it streps down because of the heat (see here). After that it does 880lm for 2.5h which is reasonable, but not that great for a 1x 26650 light. 

Generally it looks good though. 

If you want a constant 2000+ lumens I would mod a Convoy L6 with the smo reflector and the Kaidomain driver. It's a beefy light that can take the heat. The same light with the single cell tube and de-domed Luminus SST-40 (3.5-4mm^2) might get similar brightness and throw, but with a much shorter runtime.


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## Dioda (Dec 23, 2017)

Hi, im perfectly okay with turbo in short bursts, i use it only to illuminate distant targets or to point some direction. Otherwise I mainly use moonlight mode or the low to medium levels. As for the host body, im also OK with beefier 26650 single cell types, and also with the multi-tube or multi-battery type bodies. Convoy L6 is just too long, i prefer single cell flashlights. Also all the soda can types are out of consideration. My preferred reflector size would be 4-5 cm.

If there is any solid, budget friendly, well designed XHP 35 Hi thrower, even if it is a clone of a chinese clone, Im open for recommendations. I will also consider any solid mod with the XHP 35 Hi out there. Ideally single emitter, single battery cell.


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