What this EEPROM brings that a generic 2Kbit doesn't
The Microchip AT24MAC402-XHM-T is a 2Kbit serial EEPROM with a factory-programmed, unique MAC address. That pre-loaded ID saves a separate MAC-address chip or a firmware-assigned address that can collide on a network.
Supply range and bus compatibility
The 1.7V to 5.5V supply range covers the common 3.3V and 5V rails found on most MCU boards. At 5V the I²C bus meets 5V logic thresholds directly; at 3.3V the device remains fully functional with the same 1 MHz clock. No external regulator or level shifter needed for either voltage.
