ST24LC21B, ST24LW21 ST24FC21, ST24FW21 1 Kbit (x8) Dual Mode Serial EEPROM for VESA PLUG & PLAY is a 1K-bit dual-mode serial EEPROM from ST company, with 1 million erase/write cycles, 40 years data retention, 3.6V to 5.5V single supply voltage, hardware write control (ST24LW21 and ST24FW21), TTL Schmitt-Trigger, VCLK input, 100k / 400k Hz compatibility, I2C bus bit transfer range, two-wire serial interface, I2C bus compatible, I2C page write (up to 8 bytes), I2C byte, random and sequential read modes, self-timed programming cycle, automatic address incrementing, enhanced ESD / latch-up performance, error recovery mechanism (ST24FC21 and ST24FW21), VESA 2 compatible.
This handbook describes the ST24LC21B, ST24LW21, ST24FC21 and ST24FW21 1 Kbit EEPROM family, which complies with VESA Plug & Play standards. It outlines the device organization, pin‑out diagrams for DIP and SO packages, and the two operating modes – Transmit‑Only and I²C bidirectional.
The document provides absolute maximum ratings, electrical characteristics, timing diagrams, error‑recovery mechanisms, and package dimensions. Legal and licensing information is included at the end of the publication.
| Supply Voltage | 3.6 V to 5.5 V |
|---|---|
| Erase/Write Cycles | 1 million |
| Data Retention | 40 years |
| Ambient Operating Temperature | -40 °C to 85 °C |
| Storage Temperature | -65 °C to 150 °C |
| Input/Output Voltage Range | -0.3 V to 6.5 V |
| ESD (Human Body Model) | 4000 V |
| Package Types | PDIP8 and SO8 |
| Maximum I²C Bus Frequency | 100 kHz to 400 kHz |
The devices support up to 1 million erase/write cycles.
Data retention is specified as 40 years.
A single supply voltage of 3.6 V to 5.5 V is required.
Both an 8‑lead Plastic Dual‑in‑Line (PDIP8) and a Plastic Small Outline (SO8) package are offered.