Features:
CPU operates at 3.3V, has an absolute max of 130m A.
High-current IO pins are capable of 15m A source, 9m A sink; Low-current IO pins capable of 3m A source, 6m A sink.
The Due has 1 dedicated SPI port, & 4 multipurpose USART/SPI ports. The SPI port is only routed to the 6 pin header used for ICSP on Mega, but this is not used for ICSP on Due.
12V & 24V power for option. Computing faster & flash, sram bigger than mega 2560. Larger driving power than Ramps 1.4.
The Due does not have any EEPROM.