Arduino Leonardo

July 2012

The Arduino team is now shipping their latest creation – the Leonardo. It is the first Arduino to use Atmelʼs ATmegaXU4 series chip with built-in USB. This change is big and it has big benefits. In addition to the built-in USB, it offers more digital and analog pins. This comprehensive guide gives you the details you need to know to start using it with the pinout differences, hardware capabilities, new software libraries and more!

Technical Details

•     The Arduino Leonardo can be powered via the micro USB connection or with an external power supply. The power source is selected automatically.
•     The ATmega32u4 has 32 KB (with 4 KB used for the bootloader). It also has 2.5 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library).
•     The Leonardo can be programmed with the Arduino software (download). Select "Arduino Leonardo from the Tools > Board menu (according to the microcontroller on your board).

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 40 mA DC Current for 3.3V Pin 50 mA Flash Memory 32 KB (ATmega32u4) of which 4 KB used by bootloader SRAM 2.5 KB (ATmega32u4) EEPROM 1 KB (ATmega32u4) Clock Speed 16 MHz

[Source] Arduino Leonardo 

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