The Crowduino Leonardo is a microcontroller board that completely compatible with the Arduino Leonardo. It is 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), 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 a AC-to-DC adapter or battery to get started.
The 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 a mouse and keyboard, in addition to a virtual (CDC) serial / COM port.
T Working Frequency: 16MHz
Digital I/O Pins: 20
DC Current per I/O Pin 40mA
DC Current for 3.3V Pin: 50mA
Flash Memory: 32KB of which 4KB used by bootloader
Power Supply: USB 5V or External Power 7~12V