7135 Stacking on a 17mm DrJones H17F for higher current in high and turbo only

Would anyone be able to say whether or not it would be possible to add 7135’s to this driver to allow for higher current to the LEDs but in high and turbo modes only?

From what i can tell (with my admittedly VERY limited knowledge of these things), it looks like this driver “engages” different fets depending on the mode selected.

My intent is to build a 3up with this emitter setup however I’d like to be able to drive the LED’s to their max. Ideally getting 3300lm in high or turbo but still have a super dim “firefly” mode (preferably less than a single lumen).

Please feel free to offer other driver/emitter combos that may be better suited to this intent. Mainly “holy shit” output in high/turbo and “is it on?” in firefly/moonlight mode.

Thanks ahead of time for the input!!

The FET on this driver delivers (in turbo mode) as much current as the cells are capable of and the LEDs can take. Stacking 7135s will only influence the lower modes.

I see. Thanks for the clarification!

Is there a way that I can figure out what the minimum output would be on it’s lowest setting to ensure it will be low enough for what I want in firefly/moonlight mode?

+1

Well, acutally the Direct Driver will pull out maximum current from your battery, so, you can not increase current on high and turbo mode by adding more compoment
you can do spring bypass,using thicker wire and an IMR battery,

Note that the FET in the H17F is smaller and has a higher resistance than FETs used in typical FET drivers. This will limit the current more in turbo mode. It will still be bright; I would estimate 80-85% of the output of a larger FET.

A FET+1 driver from mtnelectronics will do what you want I think. The lowest modes use the 7135 chip so you can get very low modes.

There are advantages and disadvantages to each driver (performance, user interface options).

I was also considering this driver with the guppydrv firmware but wasn’t sure how low the “ml” (moonlight) mode would go so I started looking at the dr jones one since it allows for programming the output for each mode.

I don’t expect the max output mode to be used very much but want it there just in case and would like it to basically be the sun in my hand if possible. The low and moonlight/firefly modes will see MUCH more use for my applications.

If you get that driver I would recommend the Bistro FW.

I have used both drivers and I think the H17F will allow a lower low mode, plus the more precise customizability.

Second the Bistro suggestion! I just finished a build in a titanium host using a triple with the latest high binned 219C’s and I am considering removing the Mountain driver because it is just to low resistance on turbo. The light pulls almost 12 amps from a 30Q and gets way to hot way to fast. I am actually thinking about putting in the H17f to tone it down just a little.

The moon light is better on the H17f, but the turbo is better on the Mtn 17mm FET+1 newest version.

It’s lowest setting is 1.5 ma. Cree list the XP-L V3 at 51.8 lumens at 100 ma. I’d guess at or just below 1 lumen for your triple. That’s for your driver as is from Mountain Electronics.

At 1.5mA you may get 220-230 L/W efficiency at highest bins
There is like no difference between triple and solo led at that currents

Typical voltage is around 2.7V so with 1.5mA you got 4.5mW
So pretty much 1 lumen

Dude, it is running bistro on the latest driver and with ml enabled it is brighter that any of the other lights I consider to have a good ml mode, including a triple S2+ that I built. It is really bugging me.

So it’s sounding like a triple may not be the way to go for the low-low moonlight modes i’m working towards. Maybe a better bet to do a single XP-L2.

Not sure if i’m figuring it right but if i divide the max lumen output of the XP-L2 by the max current in mA i should get the max lumens per mA, right?

If so then the XP-L2 would give me a little over half a lumen at 1.5mA. That’s still a little more than my basis for comparison’s firefly mode but will most likely be acceptable.

This whole exercise may have to go from a single “best of both worlds” light to a pair of lights. Disappointing…

I really do appreciate all the input. Thanks a ton guys! Learning a lot here.

These kind of drivers realize moon mode and the lowest low modes by PWMing one AMC7135 chip. So actually with a triple, each LED is driven by pulses of ~117mA, theoretically. In reality, these low PWM values at high frequencies tend to not fully turn on the 7135 chips, especially true for the moon mode, so the current for each pulse should be lower than 117mA, but nowhere near 1,5mA…

So you have to be able to tweak the PWM value and flash firmware to achieve the lowest possible moon mode with these drivers. You can get very low moon modes that way, even too low to be useful as far as I’m concerned.

Richard (RMM) can’t go that low with the PWM values for the drivers he’s selling, because he has to make sure it lights up in almost all cases for everyone in every setup.

Ok, so back to my original plan then. Does the Dr Jones H17F revert to a singe 7135 for low and moon modes? If so, that would mean the 3 leds would be sharing the current (which his firmware lets you set) coming from the driver so each would see 1/3 of that current resulting in me being able to truly dial in the moon mode I want from basically no light to just enough? Then, in turbo, the 7135’s essentially get outta the way and the leds just drink what they can from the battery?

My old triple that had a ml mode to die for was lost by my wife! It was an XP-G2 Fet+1 driven that I built and modded the firmware for the best possible ml mode. It was way low, very easy on the eyes at night. I suspect the purchased drivers are a little higher output on ml mode to guarantee that they will always work with any normal combination.

yes

yes, you could increase the brightness further by stacking chips on the one 7135 chip

yes, they drink what they can limited by the voltage drop in battery, FET, springs, traces, wires, contacts…