Serial EEPROM, Standard - STMicroelectronics

ST's serial EEPROM portfolio includes a very wide range of products, featuring the major bus types:

I²C, with densities ranging from 1 Kbit to 2 Mbits, and a bus speed of 1 MHz or 400 KHz. This is the M24 series.
SPI, a faster bus, with densities ranging from 1 Kbit to 2 Mbits, and a bus speed from 2 MHz to 20 MHz (depending on Vcc value). SPI EEPROM feature a Chip Select input (unlike I²C EEPROM). This is the M95 series.
Microwire, a legacy bus, with densities ranging from 1 Kbit to 16 Kbits. This is the M93 series.

All these products are specified for operation at 5.5 V Vcc, and work down to 1.8 V Vcc (in some cases down to 1.7 V Vcc). Most popular packages are SO8, TSSOP8, UFDFPN8 (MLP 2x3) and WLCSP (Wafer Level Chip Scale Package).

Some specific functions include (shown as "Other Functions"):

Lockable Identification Page (I²C or SPI bus), where user data can be programmed and permanently locked outside the main memory array, a generic part number includes "-D" (example: M24512-DR)
Programmable block protection (Microwire bus), this is the M93S series.

Most of standard serial EEPROM products are specified for operation at 85°C max and are qualified to comply with automotive AEC-Q100 standards. For full automotive grade compliant products, visit automotive serial EEPROM section.