This is the Atmel ATmega32U4 chip used in Arduino Leonardo boards
Note: This chip DOES NOT have the Arduino Bootloader installed.
The ATmega32U4 is a low-power CMOS 8-bit microcontroller based on the AVR enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega32U4 achieves throughputs approaching 1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.
The ATmega32U4 provides the following features: