Key facts
- Brand
- STMicroelectronics
- Model
- ST24FC21B
- Industry
- Industrial
- Documents
- 2
- Languages
- EN
- Last added
- 2012-06-06
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ST ST24LC21B ST24LW21 ST24FC21 ST24FC21B ST24FW21 handbook
This document describes the ST24LC21B, ST24LW21, ST24FC21, ST24FC21B, and ST24FW21 devices, which are 1Kbit electrically erasable programmable memory (EEPROM) organized in 128x8 bits. The products support a single supply voltage ranging from 3.6V to 5.5V or 2.5V to 5.5V and offer up to one million erase/write cycles with 40 years of data retention.
The devices operate in two modes: Transmit-Only mode for VESA PLUG & PLAY applications and I2C bidirectional mode. Key features include hardware write control options, TTL Schmitt-trigger inputs on the clock pin, automatic address incrementing, and enhanced ESD/latch-up performance. Specific models like ST24FC21 and ST24FW21 feature an error recovery mechanism.
STMicroelectronics ST24FC21B specifications
| Memory Capacity | 1 Kbit (x8) |
|---|---|
| Organization | 128 x 8 bits |
| Operating Temperature Range | -40 to +85 °C |
| Supply Voltage (VCC) | 3.6V to 5.5V or 2.5V to 5.5V |
| Endurance (Erase/Write Cycles) | 1 Million |
| Data Retention | 40 Years |
Source: ST ST24LC21B ST24LW21 ST24FC21 ST24FC21B ST24FW21 handbook
All STMicroelectronics ST24FC21B documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
What is the difference between ST24LC21B and ST24FC21?
ST24LC21B is VESA 1 compatible, while ST24FC21 is VESA 2 compatible.
From: ST ST24LC21B ST24LW21 ST24FC21 ST24FC21B ST24FW21 handbook
How does the Write Control (WC) pin function?
For ST24LW21 and ST24FW21, the WC signal enables or inhibits write instructions; if WC=1 writes execute, if WC=0 they do not.
From: ST ST24LC21B ST24LW21 ST24FC21 ST24FC21B ST24FW21 handbook
What is the supply voltage range for the ST24 EEPROMs?
They operate from 3.6 V to 5.5 V, or from 2.5 V to 5.5 V for single‑supply versions.
From: STMicroelectronics ST24LC21B/ST24LW21/ST24FC21/ST24FC21B/ST24FW21 EEPROM Datasheet
How many erase/write cycles can the ST24 EEPROM endure?
The devices are rated for up to 1 million erase/write cycles.
From: STMicroelectronics ST24LC21B/ST24LW21/ST24FC21/ST24FC21B/ST24FW21 EEPROM Datasheet
