Here are the key details about the Leonardo R3 board:

ATmega32U4 Microcontroller: The Leonardo R3 board is built around the ATmega32U4 microcontroller. This 8-bit microcontroller operates at 5V and has 32KB of flash memory, 2.5KB of SRAM, and 1KB of EEPROM. It is known for its built-in USB support, which allows it to act as a USB device, making it suitable for USB HID (Human Interface Device) applications.

Micro-USB Connector: The board features a micro-USB connector as its primary interface for connecting to a computer or power source. The micro-USB port is used for both power supply and USB communication with the microcontroller.

Compact Form Factor: The Leonardo R3 is designed with a compact form factor, making it suitable for a wide range of embedded systems and projects, including those with space constraints.

Built-in USB Functionality: One of the standout features of the Leonardo R3 is its native USB connectivity. It can emulate a USB keyboard, mouse, or other HID devices, allowing for seamless interaction with a computer. This feature is particularly useful for projects involving input devices, game controllers, and automation.

GPIO Pins: The board provides a set of GPIO (General Purpose Input/Output) pins, including digital pins, analog pins, and power pins. These pins allow you to connect various sensors, actuators, and other electronic components to the board.