Fenix L2P 3 watt driver.

For those not interested in the 1.7 watt single cell driver, I thought I'd post about using it for the L2P. With 2 NIMH cells, this driver can produce a max of 3.5 watts and nominal of 3.2 watts of drive, and it will still work with one cell and the power out is halved. It runs 85% efficent, and draws 1.6 to 1.7 amps from the cells. Nice circuit for the Fenix or any other 2 AA cell flashlight you might want more power out of. I also can make this circuit 14.4mm (.57 in.) diameter so it can be used to modify a broader number of flashlights. Stock is 16mm diameter.

Miller,
Can the 3 watt L2P driver be used with the 2-stage resistor trick to the Fenix tail switch? The stock L2P regulator can't be modified that way. A MillerMods L2P 3 watt TWOH LuxeonIII with 2-stage 5 ohm brightness levels sounds very interesting.

BentHeadTX said:

Miller,
Can the 3 watt L2P driver be used with the 2-stage resistor trick to the Fenix tail switch? The stock L2P regulator can't be modified that way. A MillerMods L2P 3 watt TWOH LuxeonIII with 2-stage 5 ohm brightness levels sounds very interesting.

Click to expand...

Yes, two 10 Ohm resistors in parallel will drop the circuit out of regulation and it will then draw 330mA from the cells for many hours. The same mod. with this circuit on the L1P will draw 120mA from the cells. You have to use two 1/4 watt resistors with the L2P because the voltage drop and current through the resistors is too high for one 5 Ohm resistor.

My 2D Mag mod Madmax+ R2H (LuxeonI at 800mA) is presently in Iraq. Toying with the idea of using your 3.2 watt curcuit and a Luxeon K2 with SWAH bin code as a possible refresh of the light. No need for the 2-stage, those 11,000mAH NiMH D cells can handle the current.

Miller,
I have been following your mods religiously, since I just acquired a L1P and love it, but will also consider using the L2P for the longer run-time with your HP mods.

Please let me know how things are going with further testing, as I would like to do some boosting along with your tail switch mod. When do you anticipate having kits for sale?

At work we have a Cadex 7400ER that analyzes lead acid, NiMH, NiCad, Li-Ion, Li-Po, primary lithium cells (3 minute test without discharging) with many different parameters to play with.

This is what happens when running a Sanyo Industrial 2300mAH AA cell

850mA charge/1.7 amp discharge to 1.00V 1904mAH or over an hour runtime in a MillerMods L1P with that battery discharging to 1.00 volts

Can't wait until the MM L1P arrives as I have some batteries that can handle the 1.7 amp load it draws. Well, as long as the regulator can deal with dropping to 1.00V.

BentHeadTX said:

At work we have a Cadex 7400ER that analyzes lead acid, NiMH, NiCad, Li-Ion, Li-Po, primary lithium cells (3 minute test without discharging) with many different parameters to play with.

This is what happens when running a Sanyo Industrial 2300mAH AA cell

850mA charge/1.7 amp discharge to 1.00V 1904mAH or over an hour runtime in a MillerMods L1P with that battery discharging to 1.00 volts

Can't wait until the MM L1P arrives as I have some batteries that can handle the 1.7 amp load it draws. Well, as long as the regulator can deal with dropping to 1.00V.

Click to expand...

Thanks for the battery analysis, that's very interesting. 1 volt at 1.7amps equals 1.7 watts minus losses would give about 1.445 watts to the lux at the end of the charge.
I'll have your order ready as soon as I get the correct order sent to me. I ordered L1P's and Lighthound sent me L0P's. I'm ordering again today and I'm just going to keep the L0P's for later. Sorry about the delay, I'll let you know before I ship and you can pay me then.

No pressure,
That will give me time to play around with batteries at a 1.7A load. Next battery up--Powerex 2500. 1.45 watts at 1.0 volts is great regulation and will give me over an hour of runtime. Sorry to hear about the order mix-up, it is much more aggrivating for you than it is for me.