You, like many, probably started your microcontroller journey with an Arduino Uno. Eventually though, chances are you moved on to smaller boards like the Nano, which measures in at just 1.77” x .71”, or the even tinier Pro Micro at 1.3” x .7”. Nionics, however, has announced a new board called the ATTO that they claim is the world’s smallest Arduino-compatible. It comes in a minuscule .45” x .40” form factor, which works out to just an .18-square-inch area. To get a sense of its size, consider that the Nano has a comparatively massive 1.26-square-inch footprint.
The ATTO features the same ATmega32U4 as the Pro Micro, allowing it to act as a custom human interface device (HID) if you so desire. It even has a built-in RGB LED for your blinking needs. A microUSB port provides power and programming for the board, or a VIN pin can accept between 3.3 and 13V.
To pull off this little package, IO pins are reduced compared to some of its full-sized cousins, and you’ll need to deal with a smaller pin pitch than you’re probably used to at .05” (or use an adapter). Also, it won’t be available until October. But if you can wait a few months, it looks like a great way to embed intelligence where a dev board couldn’t have fit previously!