Small arduino for smart watch

Hi,

I'm trying to make a smart watch, and I could use your advice on a small arduino board that has the following characteristics:

  1. No larger than 1.5 inches by 1.5 inches in size;
  2. Has bluetoooth or WIFI on-board;
  3. Has connections for a Lithium Ion battery + charging circuitry, so you don't have to remove the battery to charge it externally;
  4. Has on-board USB for battery charging and programming;
  5. Has the right pins to attach a small TFT display, like this one: Link

I would think this would be a fairly common request, but I've searched Sparkfun, Adafruit, and DFrobot and the closest thing I've found is THIS, which does not have the battery charging circuitry and may not have enough pins for the TFT display.

Do you have any recommendations of a small board that has all this, or perhaps another vendor I could search? I'm only aware of Sparkfun, Adafruit, and DFrobot.

Thanks in advance.

I think you are expecting too much and you are going to have to assemble different parts to get the functionality you want. Yours is a very specific requirement. Manufacturers only make products that lots of people want to buy.

...R

First get a prototype working perfectly, using any sized boards.

Then design (or have someone design) a custom PCB with just the parts you want.

Just Google
Arduino Watch
For examples of different types like this one.

I don't think you'll get a board that size with all them features.
But a watch project that has similar features and size is this one on Hackaday: OSHWatch | Hackaday.io
Quite a cool looking watch.

Thanks for the replies!

Unfortunately, I don't have the time or energy to do a whole custom PCB anymore :frowning: I have a 2 month old baby, so I was really hoping to make this more of a weekend project type thing using existing parts.

I assumed there would be a lot more out there, since wearables are all the rage right now. I thought my list was pretty standard for a wearable, but it sounds like maybe I've overshot.

Adafruit “hallowing” comes close. A bit bigger than you want...

Thanks! That's interesting, I'll have to take a closer look at it.

Just to be clear, the board I'm looking for doesn't need to already have a TFT display attached, it just needs to have the right pins so that I can purchase/connect a separate TFT display.

WeMOS D1 mini comes very close. 34.2 x 25.6mm, WiFi built in. Those displays connect over SPI, so easy to connect.

The WeMOS D1 does seem very close. Seems to have everything but the LiPo charging circuitry, unless I missed that. Thanks for the suggestion!!

Have a look at Arduino watch - Bluetooth and more | development board.

icydash:
The WeMOS D1 does seem very close. Seems to have everything but the LiPo charging circuitry, unless I missed that. Thanks for the suggestion!!

The Microchip MCP73831 is a very convenient (if small) device for charging a single LiPo

...R

Robin2:
The Microchip MCP73831 is a very convenient (if small) device for charging a single LiPo

It is.

Don't forget to fit the 4u7 capacitor on the battery charge output though, if you dont the chip gets so hot it unsolders itself ............................

I have built my own arduino smart watch. A quick write up is here: GadgetWatch 2.0 - an arduino smart wristwatch - Exhibition / Gallery - Arduino Forum

Building a watch is a great project, but to make a useful and practical unit is not trivial. It is a careful balance between battery life, physical size, simplicity of construction, ascetics, function, durability, cost, and R&D investment. You could have everything you want, but it might be 3 inches thick. Or maybe you could forgo bluetooth or wifi, or find a different display, and maybe have something that would be better. It's all depends on what you can manage and what your end goal is.

I would advise that you begin putting parts together, see what works and what doesn't, and refine your goals as you progress. This is a great opportunity to learn many different aspects of electronic design.

Thanks everyone for all these helpful replies. I plan to look through all of your suggestions in more detail tomorrow.

If it helps, my goal with this is fairly basic. The watch is just for conveniently logging data. The watch will have a GUI (to output current stats) and three buttons through which I can input data one of three options, and it'll periodically upload the data to a shared online account. I don't need many fancy bells and whistles, really just the minimum requirements I listed in my initial post. But it does need to be small enough to serve as a watch and look halfway professional.