Key facts
- Brand
- STMicroelectronics
- Model
- M24256-BW
- Industry
- Industrial
- Documents
- 2
- Languages
- EN
- Last added
- 2012-08-09
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ST M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF 256-Kbit serial I C bus EEPROM handbook
The M24256 is a 256-Kbit (32 K x 8 bits) EEPROM compatible with I2C bus modes at 1 MHz, 400 kHz, and 100 kHz. It features a single supply voltage range from 1.7 V to 5.5 V depending on the specific device grade (BW, BR, BF, DR, DF). The device supports random and sequential read modes, byte and page write operations, and includes an optional Identification Page for M24256-D variants that can be permanently locked.
The document provides detailed signal descriptions for SCL, SDA, Chip Enable (E2, E1, E0), and Write Control (WC). It outlines memory organization, device operation sequences including start/stop conditions, and specific instructions for write and read operations. The datasheet also lists maximum ratings, DC and AC electrical parameters, and mechanical data for various package types including TSSOP8, SO8, UFDFPN8, and WLCSP.
STMicroelectronics M24256-BW specifications
| Memory Capacity | 256 Kbit (32 Kbytes) |
|---|---|
| Page Size | 64 bytes |
| Clock Frequency | 1 MHz |
| Supply Voltage (BF/DF) | 1.7 V to 5.5 V |
| Write Cycles | More than 4 million |
| Data Retention | More than 200 years |
Source: ST M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF 256-Kbit serial I C bus EEPROM handbook
All STMicroelectronics M24256-BW documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
What is the memory organization of the M24256?
The M24256 is organized as 32 K x 8 bits.
From: ST M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF 256-Kbit serial I C bus EEPROM handbook
Can the Identification Page be locked?
Yes, the Identification Page can be permanently locked in Read-only mode.
From: ST M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF 256-Kbit serial I C bus EEPROM handbook
What supply voltage range is required for the M24128‑BW and M24256‑BW devices?
They operate from 2.5 V to 5.5 V.
How many erase/write cycles can the EEPROM endure?
The devices are rated for more than one million erase/write cycles.
