This is Leonardo Board, Arduino’s first development board to use one microcontroller with built-in USB. Using the ATmega32U4 as its sole microcontroller allows it to be cheaper and simpler. Also, because the 32U4 is handling the USB directly, code libraries are available which allow the board to emulate a computer keyboard, mouse, and more using the USB-HID protocol!
It has 20 digital input/output pins (of which 7 can be used as PWM outputs and 12 as analog inputs), a 16 MHz crystal oscillator, a micro USB connection,a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with an AC-to-DC adapter or battery to get started. Note that on the Leonardo, the Serial class refers to USB (CDC) communication; for TTL serial on pins 0 and 1, use the Serial 1 class.
The Leonardo differs from all preceding Arduino boards in that the user-programmable ATmega32U4 AVR microcontroller has built-in USB functionality, eliminating the need for a secondary processor. This makes the Leonardo more versatile: in addition to supporting a virtual (CDC) serial/COM port interface, it can appear to a connected computer as a mouse and keyboard.
It’s a 100% pro micro Arduino Compatible Board.
Board Mode: LEONARDO R3
Input Voltage (limit)
Analog I/O Pins
Digital I/O Pins
PWM Digital I/O Pins
DC Current per I/O Pin
DC Current for 3.3V Pin
32 KB (ATmega32u4) of which 4 KB used by bootloader
Dimensions in mm (LxWxH)
Robotics, DIY Kit and Projects that require High Speed Processing.