The Microchip AT93C66B is a 4 Kb Microwire (3-wire) Serial EEPROM organized as either 512 x 8 or 256 x 16, selectable in hardware using the ORG pin. The device is optimized for use in consumer, industrial, and automotive applications where reliable and dependable nonvolatile memory storage is essential. The EEPROM is available in a variety of space-saving packaging options.