Most recent mod- Dual Atty Mod

[dattmavis19]

I made this dual atty mod using the NiMh charger that madvapes sells. It does work perfect for making a PV, the 14500 batts fit great. I used the bottom half of the existing board for the batts, it already had batt holders soldered to it, though i had to scratch off some of the copper stuff on the board to keep it from shorting out since i used 2 separate circuits instead of both batts in parallel. I used the 5v 3A mosfet chip from madvapes, cut one of their little square circut boards in half and made 2 mosfet modules with the chip, 480 Ohm resistor, and 10uf capacitor (diagram here: MadVapes e-Cig 'How To' Tutorials • View topic - LDO-5-volt-3-amp-regulator Diagrams
I only used 1 battery per circuit however, the mosfet is just so i could use the 100g tac switches. I wanted a DPST switch so i could just one, but madvapes and radioshack dont stock them, so i just stuck the tac switches together.
There is no master on/off due to space limitations, but this isnt something i'll be carrying in my pocket so i dont see the need for it. There isnt really much space left either, the 2 mosfet boards and 2 atty connectors pretty much use up the top, and since i'm using 2 batts there isnt much space left. I wanted to put in 3 LEDS, red yellow green, that light up when both buttons are pressed, and i may in the future, but it will deff have to be board-mounted because of the space limitations.

I'm pretty proud of this one, its deff my favorite sofar, making the mosfet boards was a challenge for me because it was the first time i've worked on a circuit board and my soldering skills are still mediocre, but i'm really happy with how it turned out. Breadboarding the circuit also helped immensely, being able to hook it all up and test it, and know it works before soldering it. I would deff recommend a breadboard to anyone starting out or even just working on more complicated circuits, mine only cost $7 at radioshack. The "helper" with magnifying glass(thing that holds stuff in place while you work on it, $15 at radioshack) is also an amazing help.

Let me know what y'all think, comments and critique are welcome.



Sorry there aren't more pics of assembly, i just got into it hardcore and didn't want to stop ha.

 

[WillyB]

Quite the confusing mod. Why not use both 14500s paralleled? A single 14500 is pretty useless these days especially with lower res offerrings, a pair though is rather sweet. Not just longer vapetimes but higher initial voltage and less voltage drop and no matter how you use it the batteries will always be balanced, the same volts.

I used the 5v 3A mosfet chip from madvapes, cut one of their little square circut boards in half and made 2 mosfet modules with the chip, 480 Ohm resistor, and 10uf capacitor

Seems like an odd choice , why not just get a small 3 pin mosfet a 1k -5k resistor and use that? Seems weird to use a linear voltage regulator when all you need is a mosfet. And nowhere in the datasheet for that regulator does it call for a 10uf capacitor. (????)

I don't know whose diagram this is but this is basically how it's wired.

There is no master on/off due to space limitations,

Well with your regulators any time you have the batteries in you are using current, even when not vaping.

Just a few random thoughts.

 

[MadmanMacguyver]

I second Willy B on the master switch...you really need it to stop the slow drain when you are not using it...

 

[dattmavis19]

Idk, this is the first time i've done something this complicated, it works at least. I don't think it drains the batts either, they last 2 days with what i consider "heavy" use.

But the mosfet chip, i went with that because that was what was available on madvapes at the time. and for wiring it in parallel, i didn't do that because i'm running two attys, not just 1.