The CAT64LC40 is a 4kb Serial EEPROM which is configured as 256 registers by 16 bits. Each register can be written (or read) serially by using the DI (or DO) pin. The CAT64LC40 is manufactured using ON Semiconductors advanced CMOS EEPROM floating gate technology. It is designed to endure 1 000 000 program/erase cycles and has a data retention of 100 years. The device is available in 8-pin DIP SOIC and TSSOP packages.