Summary of Arduino Leonardo AVR Development Board
The Arduino Leonardo AVR Development Board is built on the Atmel ATmega32u4 microcontroller, featuring 20 digital I/O pins, 7 PWM outputs, and 12 analog inputs. Operating at 16MHz with a 5V supply, it uniquely integrates USB communication, allowing it to function as an HID device like a mouse or keyboard without a secondary processor. It includes essential components for easy connection and operation via USB or external power sources, making it suitable for versatile microcontroller projects.
Parts used in the Arduino Leonardo AVR Development Board:
- Atmel ATmega32u4 microcontroller
- 16MHz crystal oscillator
- Micro USB connection port
- Power jack
- ICSP header
- Reset button
Arduino Leonardo AVR Development Board is a microcontroller board based on the Atmel ATmega32u4. It offers 20 digital IOs (of which 7 can be used as PWM outputs and 12 as analog inputs), a 16MHz crystal oscillator, a micro USB connection, a power jack, an ICSP header, and a reset button. 
The Arduino Leonardo differs from all preceding boards in that the ATmega32u4 has built-in USB communication, eliminating the need for a secondary processor. This allows the Leonardo to appear to a connected computer as an HID, such as a mouse or keyboard, in addition to a virtual (CDC) serial / COM port. The Leonardo board 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.
Specifications
- Microcontroller: ATmega32u4
- Operating voltage: 5V
- Input voltage (recommended): 7-12V
- Input voltage (limits): 6-20V
- Digital I/O pins: 20
- PWM channels: 7
- Analog input channels: 12
- DC current per I/O pin: 40mA
- DC current for 3.3V pin: 50mA
- Flash memory: 32Kb (ATmega32u4)
of which 4Kb is used by bootloader - SRAM: 2.5Kb (ATmega32u4)
- EEPROM: 1Kb (ATmega32u4)
- Clock speed: 16MHz
For more detail: Arduino Leonardo AVR Development Board
