pArduino Pro Micro Usb is an ATmega32U4 board running at 5V/16MHz. It is the smallest Arduino -Compatible board. It has high speed PWM with programmable and resolution from 2-11bits.it is Supported under Arduino IDE v1.0.1. it can accept voltage up to 12VDC. It has USB connectivity on-board and on board power and status LEDs./p
pThe Arduino Leonardo is a microcontroller board based on the ATmega32u4 that includes 20 digital input/output pins where 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. We can simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to operate . The Leonardo has built-in USB communication that eliminating the need for a secondary processor. This allows the Leonardo to appear to a connected computer as a mouse and keyboard. The drivers are automatically installed plugging with an USB cable to the PC. The software can be found in the official site ./p