Driver is from Intl-outdoor.com, but he does not sell it anymore.
Official specifications:
Suitable for 1 or 2*18650 or 26650 batteries
Input voltage: 3-8.4V
Current and Modes:
High (2.8A) - Medium (700mA) - Low (100mA) - Strobe - SOS
High (2.8A) - Medium (700mA) - Low (100mA)
Current on High with 1 cell 2.5-2.6A
Constant current circuit (2 cell only)
Memory function
This driver does not use PWM
PCB Diameter: 18.5mm
Contact board diameter: 20.3mm
Total height: 8.9mm
Gold plated contacts
Low voltage protection 1 cell: at 3V the light will step down to low mode and start flashing
Low voltage protection 2 cells: at 5.8V the light will step down to low mode and start flashing
Reverse polarity protection
Tinned leads
You can change between the set of modes by turning on the flashlight on low mode for about 3 seconds,the light will flash once, then quickly turn off the flashlight and then turn it on.
Measurements
Tested with XM-L2
Diameter 18.5 mm & 20.2 mm
Max. height: 9.3 m
Strobe 15 Hz 44% on time
Mode set 1: High, medium, low, Strobe, SOS
Mode set 2: High, medium, low
When doing a low to high test the led did not turn on.
The driver has memory, the actual mode is stored when the light is off for a short time.
A off/on will select next mode, the off has to be rather long, not to select next mode.
The driver can be used with 1 or 2 LiIon batteries in series.
The low voltage warning only works with 2 batteries.
High
The drivers has very good regulation and good efficiency. It turns down power at 6.5 volt and battery warning comes on at 5.8 volt.
As usual efficiency and power calculations are wrong when the light is flashing.
There is a maximum of 1.6 watt lost in the driver.
And a bit above 9 watt to the led.
With one cell, the stabilization is not that good (Led current varies between 3 and 4 volt).
The driver drops to medium mode at about 3.3 volt, this is good for keeping the led on.
There is no low voltage protection, but the driver turns off at 2.5 volt, i.e. minimum voltage for 2900/3100/3400 Panasonic cells.
With one cell the loss in the driver is slightly lower.
The output does not contain any noise.
The low voltage warning is slow (2 sec cycle) flashing on the led.
Medium
Medium has the same good stabilization and does not step down, it goes directly to low battery warning at 5.8 volt.
The led power is 2 watt.
With lower led power, the driver can sustain the medium level down to about 3.1 volt and it has very good efficiency.
Also with one cell the led drive level is 2 watt.
Again a very smooth output, no traces of any pwm or driver regulation.
Low
On low the regulation is also good, the efficiency is slighty down.
The led power is about 0.3 watt.
With a single cell the driver works down to about 2.8 volt, before brightness drops of.
Again a very smooth output, no traces of any pwm or driver regulation.
Strobe
The strobe is at 15 Hz and the brightness depends on the batteries voltage (The driver cannot reach full brightness with 3.6 volt).
SOS
With SOS it is the same.
Conclusion
The driver is a very good stabilization (Except on high with 1 cell) and good efficiency. The mode change could be better.
There is also very little space for mounting of the two led wires.
Sweet! I knew this driver would deliver in terms of efficiency and output! Very nice to see it confirmed on paper. Thanks for the review!
Dont worry about that IOS does not sell it anymore.. FT have a very good price on it, although with a bit "flimsier design" (only wires between the contact and driver board.) Its being solder from other stores too.
I think Fancyflashlights have exactly the same as the one tested. Price is good.
I got an LD-2C, better design in, not as tall as this one and the inductor is shielded. Such inductors like on the LD-29 can actually break on high impact, actually on one of my LD-29 the inductor broke just by dropping the driver from the table, well a part of it and of course not the copper.
Did someone tested LD29 (Convoy L2) with 4 battery Ni-Mh type C (same size as 26500) in configuration with two extension tube (3 x 26650)?
The voltage will start from 4 x 1,3V=5,2V, which is higher than 4,2V on one cell li-ion. Could this be a problem for driver?
Hi Tangra,
I did not test it, so I can only guess while giving this a bump. My guess is it will work. Here’s why:
It’s a buck driver (step-down-converter) with stated “Input voltage: 3-8.4V”. The buck circuit itself can cope with any input voltage inbetween, so it will not be damaged with your 4x1.3V. Take the 4th graph of HKJ and extrapolate the red line to 5.2V.
What could interfere is the low voltage protection in the firmware of the driver. According to the 1st graph above, LVP kicks in at 6.5V and again at 5.8V. We don’t know if it’s a threshold or a voltage spectrum where LVP triggers and down to what voltage. We only know 5V is safe according to HKJ’s testing.
But when turned on the Ni-MH are sagging. Even when in the buck driver I-in is smaller than I-out, it still needs 2.25A (and rising) to deliver the 2.75A to the LED. For an Eneloop (as example) that’s demanding to nigh impossible. So the voltage drops instantly, and that’s why my guess is it will work.
In the end it will depend on the range of the LVP in the firmware and the initial voltage drop of the cells used.
I did the test.
With 3 cell Ni-Mh C battery type (TRONIC from LIDLl) it is work like one cell Li-Ion. Except that this battery can not give enough hi current and high mode visual has same lumens. Probably with other hi-quality Ni-Mh C battery type no problem to reach 1000 lumens. It is what I have expected. Unfortunately for 3 battery C size I need dummy cell.
With 4 battery C size driver work only on high mode. This time high mode has more lumens then 3 x C battery. On low mode it works few seconds and stops. There is no middle mode.
Probably MCU can not detect properly 5,2V.
I have not tested with alkaline battery 1,5V because they are not useful for such flashlight.
There is another solution for my Convoy L2 with extension tube for 3 26650 battery.
To use 3 battery Ni-Mh size 18650 with 26550 adapter.
There is on our local market such battery. http://et-battery.com/rechargeable-cells/et-h-4-3af4500-standard/
