Unsure Where To Begin

[bumba000]

Hello AdaFruit!
This is all a bit new to me, but I've been interested for quite some time. I now have a project. This is where a new chapter in my life usually begins.

I would like to produce an electronic device though I'm really not sure what the board that would be inside of it is called, or what components I would use to construct it would be called.

I would like to start with a 3.7V DC battery and optionally ramp that up from 4 to say 5.5 with optionally up to 6 or so amps. The load would be a single wire coil with a minimum resistance of maybe 0.5 Ohms.

I would like to have tree buttons. One for trigger, two and three to set voltage/wattage.

Now I understand that there will be some programming (code) required to bring this all together. That should go pretty well as I've been writing code (several languages) for years now...

Essentially what I'd like to create here is an ECIG type device.

Any and all help and advice is greatly appreciated so long as it's helpful and it's what I want to hear.

Thanks in advance,
John

[adafruit_support_bill]

First, you will need to find a battery capable of delivering 6A. We have this one: https://www.adafruit.com/product/353
Controlling current to the battery can be done with any small microcontroller that supports PWM and a MOSFET like htis one.. https://www.adafruit.com/product/355

[bumba000]

Thanks Bill!
Funny, I had just been looking at that and a liner module. Not so funny thing is that I have taken apart a store bought ecig and the entire pcb is barely as large as the MOSFET power part you linked to.

So the largest batteries in any of these things are high amp 18650 batteries. I guess I was a bit over when I asked for 6amps. Lets call it 3 amps.

Whatever the case, there's a lot more to it than just that mosfet power thing. What tiny little chip do I use as the brain. How do I connect that to my PC USB to program it?

I am such a newb it's pathetic really.

Thanks again, John

[adafruit_support_bill]

That MOSFET is a bit of overkill, but it's real simple to work with. You could drive it with the PWM pin on one of these: https://www.adafruit.com/products/1500
That's about as small as you can get without doing your own custom circuit board.

[bumba000]

Hey Bill, Thanks again.

I've checked over this logic board and watched a pretty nutty video. So, I have learned a little bit. I am certain that I don't see the full potential of the board, but I see how it can be useful in my application. Can you help me understand how to use the board to control the resistance to the trigger leg on the mosfet? I'm trying to make the output voltage selectable by button press. Which brings up another question. This board comes with one button. Is it possible to add two more buttons? I see that adafruit offers two very small button breakouts...

Thank You, John

[adafruit_support_bill]

You don't control the resistance. You control the 'duty cycle' of the PWM. https://www.arduino.cc/en/Tutorial/PWM
You connect one of the PWM pins (0, or 1) to the gate of the MOSFET to switch the current. Then you use the AnalogWrite() function to vary the duty cycle to control the average current sent to the load.
https://www.arduino.cc/en/Reference/AnalogWrite



The button on the board is the reset button, so you can't use that for control. But we do have microswitches in a variety of sizes and shapes:
https://www.adafruit.com/categories/155

[bumba000]

OH YEAH!!! THis is what I was just finding. You've finished answering my question here. Thank You SOOO much.

Now. Is all of this adafruit stuff really made in the US? If I put this into a complete project I want to be able to say Made in USA.

Thanks again. A bunch!!, John

[bumba000]

I'm building a small shopping cart here. I am looking for a tiny screen that I can display the output voltange/wattage and possible the attached load resistance???

Tiny screen - tiny cost...
Also, is it actually possible to do what I've just described here?

Thank You

[adafruit_support_bill]

Now. Is all of this adafruit stuff really made in the US?

Electronic components come from all over. But all of our circuit boards are designed and manufactured at our factory in Manhattan.
https://blog.adafruit.com/2013/05/06/ma ... ce-nycmfg/

I am looking for a tiny screen that I can display the output voltange/wattage and possible the attached load resistance???

We do have some tiny screens, but the Trinket doesn't have enough pins or memory to drive them. You would have to step up to a larger processor.

What you have now is a pretty good starter project. I'd recommend building that for the experience first before trying for a more complex version 2.0.
https://www.adafruit.com/products/931