The M24C64 is a 64-Kbit I2C-compatible EEPROM (Electrically Erasable Programmable Memory) organized as 8 K × 8 bits. Over an ambient temperature range of -40 °C / +85 °C, the M24C64-W can operate with a supply voltage from 2.5 V to 5.5 V, the M24C64-R can operate with a supply voltage from 1.8 V to 5.5 V, and the M24C64-F and M24C64-DF can operate with a supply voltage from 1.7 V to 5.5 V ( the M24C64-F can also operate down to 1.6 V, under some restricting conditions).
The M24C64-D offers an additional page, named the Identification Page (32 bytes). The Identification Page can be used to store sensitive application parameters, which can be (later) permanently locked in Read-only mode.
