The Arduino Micro is a microcontroller board based on the ATmega32u4, developed in conjunction with Adafruit. 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, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a micro USB cable to get started. It has a form factor that enables it to be easily placed on a breadboard.
The Micro is similar to the Arduino Leonardo in that the ATmega32u4 has built-in USB communication, eliminating the need for a secondary processor. This allows the Micro to appear to a connected computer as a mouse and keyboard, in addition to a virtual (CDC) serial / COM port.
Specifications
Microcontroller
ATmega32u4
Operating Voltage
5 Volt
Input Voltage
7-12 Volt
Digital I/O Pins
20 (of which 7 provide PWM output)
Analog Input Pins
12
DC Current per I/O Pin
40mA
Flash Memory
32 KB (ATmega32u4) of which 4 KB is used for the bootloader
SRAM
2.5 KB (ATmega32u4)
EEPROM
1 KB (ATmega32u4)
Clock Speed
16 MHz
Other Arduino Nano Boards
If you are looking for a Nano board with similar functionality but also provide additional features, check:
The Micro can be powered via the micro USB connection or with an external power supply. The power source is selected automatically.
External (non-USB) power can come either from a DC power supply or battery. Leads from a battery or DC power supply can be connected to the Gnd and Vin pins.
Download the latest Arduino IDE
The open-source Arduino Software (IDE) makes it easy to write code and upload it to the board. This software can be used with any Arduino board.
The Arduino Nano is a small, complete, and breadboard-friendly board based on the ATmega328. It has more or less the same functionality of the Arduino Duemilanove, but in a different package. It lacks only a DC power jack, and works with a Mini-B USB cabl
The Arduino Leonardo is a microcontroller board based on the ATmega32u4. It has 20 digital input/output pins (of which 7 can be used as PWM outputs and 12 as analog inputs).