Review. Fasttech 1v to 3.6v single mode driver. Currents updated. Night shots added.

Flashlight Modding and DIY Parts
1

Mode

LED Current Amps

LED Voltage

Tailcap Current Amps

Sanyo 18650 at 4.2 volts

High

1.75

3.1

1.9

Ultracell LiFEPo4 at 3.6 volts

High

.7

2.9

.8

Eneloop LSD AA at 1.4 volts

High

.37

2.79

1.9

This driver was purchased from Fasttech. Link below.

https://www.fasttech.com/products/1127402

Specifications from Fasttech website.

PERIPHERAL TYPE Flashlight Driver

Electronic Components

CONSTANT CURRENT Yes

DRIVER TYPE Boost driver and Linear regulator

INPUT VOLTAGE 0.9~3.6 -volt

OUTPUT CURRENT 800 mA

PCB HEIGHT (W/O COMPONENTS) 1.5 mm

REVERSE POLARITY PROTECTION No

Flashlights

FLASHLIGHT MODES

MODE COUNT 1

MODE MEMORY

Package

PACKAGE TYPE OEM

Dimensions us | metric

DEPTH 2 mm

HEIGHT 17 mm

WIDTH 17 mm

DIAMETER 17 mm

PRODUCT WEIGHT 1.1 g

Product Numbers

FASTTECH SKU 1127402

Details:

Booster driver mode when input voltage is 1.5V or less

Linear regular (constant current) mode when voltage is between 1.8V and 3.6V

Rated at 500mA current output @ 1.5V input

Rated at 800mA current output @ 3.6V input

Lead wires pre-soldered

I had a tip of from marcl about this driver being used above its advertised voltage. This is a quick test to confirm whether or not this driver would survive or even run with the voltage above spec. To my surprise the driver did run and after a 5 minute workout the light was still shining brightly and there was not a hint off smoke coming from the driver though it was hot. The above results were taken after thirty seconds off operation. I do not recommend using this driver with any voltage higher than spec, but I may.

The usual XM-L LED was used for the testing.

Other drivers tested for comparison are,

https://budgetlightforum.com/t/-/11523#node-13488

https://budgetlightforum.com/t/-/13350#node-15649

https://budgetlightforum.com/t/-/13427#node-15739

https://budgetlightforum.com/t/-/18676

Some comparison night shots.

Firstly the AA Eneloop at .37 amps to the led.

AA LlFePO4 at 07 amps to the led.

18650 LiIon at 1.75 amps to the led.

This driver was set up in a $4.00 501B P60 host. The XP-G2 led was dedomed. It was originally a cool white tint. When dedomed the tint changed to a slightly warm color on the Eneloop and more off a neutral tint with the higher current fed from the 18650.

The last couple off shots were of the battery adaptor made for the AA size lights. It is some sort of black teflon with a 1/4 round copper pin peened over on both ends for battery contact. It was intentionally made short incase any batteries got stuck inside.

2

thanks for the review MRsDNF, looks like the driver came in fairly close to its advertised specs - that must be a pleasant surprise!

3

Yes it could be close. I dont give any accuracy on my measurements. They would have to be reasonably close I would suggest. Hopefully tonight I can get some extra measurements up and night shots as its now built into a P60 with a dedomed XP-G2.

4

Cool. Looks like a decent driver!

5

Thanks for these measurements!

370 mA LED current from 1 eneloop is indeed not bad. However, like I said in the other thread, so far I used two of these drivers and my results are inconsistent. Both draw a tailcap current of 1.8-2A from 1xeneloop (depending on charge state), but with 2xeneloop, one of them draws 2A, the other one 0.5A. I don't know if I have a defective driver or if that inconsistency is a general problem of this particular driver. One would have to test a bunch to find out.

6

Tailcap currents and night shots added to the first post.

7

19 Amps from an Eneloop?

8

You gotta love those eneloops for the amount off current you can drag out off them. The problem being is that they only last for about a tenth off a second.
The person responsible for that naughty little dot being in the wrong place has be severely flogged and sent to bed. Thanks for pointing it out.

9

I’ve been thinking about getting that driver for some time now. Great info. Thank you.

10

Thanks Ima4wheelr. Ive been using it at work with a AA NiMH and the light stopped working yesterday. It really left me in the dark. It was a P60 with a dedomed XP-G2. Its either the driver or led. I haven’t had time to check yet.

11

Thanks for the mention the MRsDNF.

It is in deed a great little driver, mine runs off 2*AA in a ‘15min Match mod minimag’. I have not measured what is going to the led but the tail cap gives me around 1.5A. If yours stopped working it might be damaged from using it on an 18650. Don’t know really.

The thing with this driver is, it’s cheap and does what it says.

Great review.

Marc.

12

I say that driver delivered it well. And it’s cheap too.

13

Thanks a lot for the review! Sticky’d.