The 25AA040-I/SN is a 4-kilobit Serial EEPROM manufactured by Microchip. It is a 4096-bit serial Electrically Erasable Programmable Read Only Memory (EEPROM) organized as 512 pages of 8 bytes each. The device is accessed via a Serial Peripheral Interface (SPI), has an operating voltage range of 1.8 to 5.5V and is available in the 8-pin DIP package. It includes EEPROM cell-level data protection, data retention of 40 years, erase/write cycles of more than 10,000 and a factory-tested data integrity. It is used in a variety of applications such as automotive, consumer, industrial, communications, and medical.