Driver ?

[Paul6ppca]

What would be a good driver for mag 3 led,K2 and 4AA battery holder?

1500ma or so could go with anything from1000 ma to 2000ma from what Ive read
Can be fixed one level or multi level output.
EDIT
This isnt my light,helping a friend.The light is a cut down1D mag,it used 4AA driving 3 seoul P4 with a task led driver,Fatman.
1 of the led burned out,and pretty sure the driver is bad.
So looking to rework this light using three K2.i would consider using 4AA nimh or (4 14500),or getting a new 3 cell14500 holder. So with that what driver would work.Im looking to put out 600 or more lumens for at least an hour.

 

[TorchBoy]

:shrug:

 

[Linger]

TorchBoy's got a nice list in his link.
Which is good because I don't understand what you indicated your set-up was. What are you looking for a driver to provide? modes, regulation, etc.
If you meant you're planning on driving three K2's off 4AA that is going to be challenge. You could try a hyperboost board but the over-head will cut into your already minimal power supply.
K2 will stand direct drive from Li-co and imr batteries, they are very resilient. Also, they usually have a lower vf, which will help you here.
You could just connect 1 K2 TFFC to the batteries, or connect the batteries 2s2p. Alternatively, use 2 K2 TFFC's in series and the 4AA's in series and hope for the best.

Cheer's,
Linger

 

[TorchBoy]

Which is good because I don't understand what you indicated your set-up was.

Me too. I decided to start work on a detailed search function for my list to help. I've got something thrown together I just need to link in.

Paul, does "4AA battery holder" mean you're not set on what sort you use, but that's the size you'll be working with? In other words, are you considering 4x 14500 (AA sized) Li-ion cells?

Edit: OK, search page ready to go.

 

[TorchBoy]

There are some interesting boost boards from 5 V and up input (which would require 4x NiMH AAs). There are some high current multimode buck boards too.

 

[Paul6ppca]

The light is a cut down1D mag,it used 4AA driving 3 seoul P4 with a task led driver,fatman.


So looking to rework this light using three K2.I would consider using 4AA nimh,or getting a new 3 or 4 cell14500 holder. So with that what driver would work.


Fatman

• Constant current regulator.
• Boost topology (step up converter), must always have a load connected.
• Dimming capability via external potentiometer.
• Onboard trimpot to set maximum output current.
• 0.80" diameter board, single sided components. 0.26" maximum thickness.
• High efficiency (typically 90% or better).
• 2.7V - 12V input voltage (being a boost converter, input voltage must be less than output voltage).
• 3V - 16V output voltage.
• Output current 1000mA (max), depends on input/output voltage differential.
• Capable of driving 1 or 2 series connected Luxeon 5W LEDs or 2 to 4 series connected Luxeon 1W or Luxeon 3 LEDs.

Here's a picture of a production board:

 

[TorchBoy]

OK, that explains the 4x AA in a Maglite. Questions:

1. Why use Luxeon K2s? Aren't they only about half as efficacious (lm/W) as just about any Crees? I don't think that you could achieve 600 lumens for an hour with them using 4x AA (unless K2s are better than I think) because 4x AA don't have enough Wh.

2. Why drop to 3x 14500 instead of 4? They are AA sized so should fit just as well as AAs.

Using step-down drivers you'll need something capable of delivering at least 2 A into three parallel Crees (ie, ~700 mA each), or using boost drivers 700 mA into three Crees in series. I found that starting from 5 V instead of 3.6 V (0.9 V per cell) gave a few more options. Some suggestions, that range up to $55 + shipping, and from single to 20 mode:

Step-down suggestions.
Boost suggestions.

 

[Linger]

Alternate idea if 14500's are possible is to use a 3xamc7135 board for driving a single led at 1050ma.
Look at download's 'multi-sink' post in B/S/T (cross posting not allowed so I can't repost his pic): the 7135 has the unique feature of regulating the current in an entire circuit. (Downloads post for detailed illustrations of this set-up) Paulcappa's request, the three 14500's are in series, and the three emiters are placed in series. Two emiters are placed ahead of the driver board, in the circuit between the batt and the board. The third emiter is wired into the driver in / out as usual. With the 7135 regulating the current in the circuit (which the emitters in series all recieve the full 1050ma amount of) and the emiters splitting the voltage, you have a fully regulated multi-driver set-up from a single emiter driver.
*edit - this means you can use a $3-9 driver instead of a $50 driver

It's a brilliant design, I'm doing one up this afternoon before work. See downloads post, there are 4 versions all perfectly illustrated.

-Linger

 

[Paul6ppca]

Can you PM me the link I was not able to find it thru the search.

Alternate idea if 14500's are possible is to use a 3xamc7135 board for driving a single led at 1050ma.
Look at download's 'multi-sink' post in B/S/T (cross posting not allowed so I can't repost his pic): the 7135 has the unique feature of regulating the current in an entire circuit. (Downloads post for detailed illustrations of this set-up) Paulcappa's request, the three 14500's are in series, and the three emiters are placed in series. Two emiters are placed ahead of the driver board, in the circuit between the batt and the board. The third emiter is wired into the driver in / out as usual. With the 7135 regulating the current in the circuit (which the emitters in series all recieve the full 1050ma amount of) and the emiters splitting the voltage, you have a fully regulated multi-driver set-up from a single emiter driver.
*edit - this means you can use a $3-9 driver instead of a $50 driver

It's a brilliant design, I'm doing one up this afternoon before work. See downloads post, there are 4 versions all perfectly illustrated.

-Linger

 

[Linger]

http://www.candlepowerforums.com/vb/showthread.php?t=168062

The pics he put up are fantastic.
There is a chain of posts explaining why the 7135 works for this but others don't, but I'm sorry I haven't included it. Maybe later if I have time.:thumbsup: