Dereelight MC-E How direct drive ?

klm74511

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Joined
May 26, 2006
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23
Hi,
as the words direct drive explain, the only way is to connect directly with two simple wires the + and - of the battery to the respective + and - of the led.
You have to think about, which battery you are going to use, because if you use a single 18650 or 17670 is safe, if you plan to use two 16340 or cr123a is not possible due to higher voltage of the two batteries in respect of the MC-E Vf.
Second for direct drive the best combination of the four die of MC-E is four parallel, in this case you need Vf 3.2 - 3.6 and VI of 2400 - 2800ma.
Resuming the best and esiest combination of a MC-E is 4 parallel die and a single 18650 battery.
Trustfire and Ultrafire 18650 protected battery have a current flow when fully charged at 4.2V of around 3.2A, that will decrease rapidly at 3.7V is about 2.7A, for experience Trustfire are better than Ultrafire, if you will use AW battery the discharge current will be higher.
The excessive V and I will be transformed in heat, but due to the generose body of the DBS, it wiil not be a problem.
I hope this can help you.

Ciao,
Marco
 

electric sheep

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Dec 13, 2008
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223
Location
UK
Thank You, i was going to use the SD pill i have but it would be a waste. I wondered why some people use boards for direct drive? That is what confused me as you see them advertised on here.
 

klm74511

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Joined
May 26, 2006
Messages
23
Hi,
someone speaks about direct drive circuit board referring to a board like this
KD SSC P7 Li-ion 5-mode driver SKU: S005025.
Otherwise people refer to direct drive board, the one will all old components removed and left only the PCB board with the wires to the led.
This option is shown on the photo below, were I modded a Tiablo A9 with a cree MC-E direct drive, using is existing board with all components removed.

TiabloA9-04.jpg


If you want to follow this second option I suggest you to don't ruin the DBS origanl pill or driver. On the DBS pill will fit any round 17mm circuit board. Keep in mind that to remove the drivers from the DBS pills is very hard, I had experience on that and I had to drill out the driver to remove it. If you want make a try, the DBS normally uses Pills that are the same size as the cheap pills that you can find at DX.
 

TexLite

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Jun 30, 2007
Messages
595
Location
Texas
Thanks looks like i will have to buy a whole new board and emitter.

You shouldn't have to buy a new board. I haven't taken and MC-E pill apart yet, but on the standard pill, the board you see with a spring isn't actually the driver, its a contact board. The actual driver is on another pcb behind the first. If the MC-E pill is the same, all you have to do is remove the second board and wire the emitter leads to the contact board.

A word of caution, as has been mentioned, only use a single cell which is capable of handling the high discharge current.

I also wouldn't advise you to go this route unless you have a way to measure the current and if necessary add resistance to get the current down. Running it without knowing the input current is a sure way to burn up an emitter, especially in a drop-in with a limited thermal path to the body.

-Michael
 

electric sheep

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Dec 13, 2008
Messages
223
Location
UK
Thanks, i have done the simplest thing and ordered one of nailbenders drop ins that runs 3A at 6v. Will run one 18650. Advise appreciated.
 
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