Smallest Arduino Pro Micro with ATmega32U4 5V/16MHz Compatible Board

Description

PICO is the development board that you’ll use whenever you work on a project where size and flexibility matter. It’s based on the ATmega32u4 microcontroller. It has 5 I/O pins, 3 analog pins, and 3 SPI enabled pads on the bottom side of the board. But, what makes it really special is the 0.6”x0.6” size and 1.1g weight, which lets you make everything around you function and work better, without a bulky board in the way.

Documentation

Datasheet

Here are the technical details for PICO: