24FC128T-I/ST

24FC128T-I/ST is STMicroelectronics’ 128‑kbit serial I2C EEPROM (Industrial temperature). It stores 16 KB of nonvolatile data and is accessed over the I2C two‑wire bus using a two‑byte word address (MSB, LSB). The device uses a fixed 1010 control code with A2:A0 to allow up to eight devices on the same bus. Memory is organized in 64‑byte pages; writes are page‑oriented and typically complete within a few milliseconds. A WP (write‑protect) pin and A0–A2 pins let you implement off/bulk write protection and multiple devices on one bus. Endurance is around 1,000,000 write cycles with long data retention. Supply voltage is a single supply (roughly 2.7–5.5 V; check datasheet for exact range). Packages include common 8‑pin options (SO8, etc.). Typical uses: configuration data, calibration tables, lookup data, and other nonvolatile storage for microcontrollers and embedded systems.

Equivalents (128-kbit I2C EEPROMs):
- ST M24C128 (M24C128-W)
- Microchip 24AA128 / 24LC128
- Atmel/Microchip AT24C128A
- ON Semiconductor CAT24C128
- Fudan Micro FM24C128 (FM24C128G)

Concise features of 24FC128T-I/ST:
- 128 Kbit (16 Kbyte) I2C serial EEPROM
- I2C two-wire interface; supports up to 400 kHz (Fast-mode) and 100 kHz (Standard)
- 16-bit memory addressing (MSB/LSB); 16,384 x 8 organization
- Page write up to 32 bytes; supports sequential writes within a page
- Write cycle time max ~5 ms
- Endurance: ~1,000,000 write cycles; Data retention ≥100 years
- Supply voltage: 2.7–5.5 V
- Address pins A0–A2 for up to 8 devices on the same bus
- WP pin for hardware write protection
- Operating temperature typically −40 to +85°C
- 8-pin package; Tape & Reel (I/ST) variant available

- Pin count: 8 pins (8-pin package).
- Function: 128-kbit I2C Serial EEPROM. Memory organized as 16 K × 8. Pins: 1 A0, 2 A1, 3 A2 (device address inputs), 4 GND, 5 SDA (I2C data), 6 SCL (I2C clock), 7 WP (write-protect), 8 VCC. The A0–A2 pins select the I2C device address; WP enables/disables writes; SDA/SCL are the I2C interface.

- Manufacturer: STMicroelectronics (ST)
- Company type: A multinational semiconductor and electronics company that designs and manufactures integrated circuits and components (memory, microcontrollers, sensors, analog devices, etc.) for global markets.

Common application areas for 24FC128T-I/ST:
- Non-volatile storage for MCU configuration, calibration data, and look-up tables
- Device identification, serial numbers, and security keys
- Small data logging for sensors, IoT, wearables, and consumer electronics
- Firmware/parameter storage in automotive, industrial, and embedded systems
- Bootstrapping/staging memory for meters and smart sensors
- General I2C EEPROM memory for persistent data in various projects

8-pin SOIC (SOP-8) package.