STMicroelectronics M24256-BFMC6TG

Overview

M24256-BFMC6TG from STMicroelectronics is a 256-Kbit I²C-compatible serial EEPROM organized as 32 K × 8 bits, operating as a nonvolatile memory slave device on standard and fast-mode I²C buses (up to 1 MHz). It supports 1.7 V to 5.5 V single-supply operation, features 64-byte page write capability with ≤5 ms write time, includes hardware write protection via WC pin, and delivers >4 million write cycles with >200-year data retention. It is used in industrial control modules for parameter storage and calibration data backup.

For engineers reviewing the M24256-BFMC6TG datasheet, M24256-BFMC6TG pinout, M24256-BFMC6TG application, or M24256-BFMC6TG equivalent, key selection criteria include I²C voltage compatibility (1.7–5.5 V), TSSOP8 package footprint, E0–E2 address configuration flexibility, WC-controlled full-array write lock, and ECOPACK2 RoHS/Halogen-free compliance for high-reliability embedded systems.

Technical Context

The M24256-BFMC6TG implements a fully compliant I²C slave interface with START/STOP detection, ACK/NACK handshaking, and 7-bit device addressing with three programmable chip-enable bits (E2–E0) for multi-device bus configuration. Its internal architecture includes an HV generator and sequencer for EEPROM programming, ECC logic across 4-byte groups for single-bit error correction, and a power-on-reset circuit ensuring immunity to inadvertent writes during power ramp-up.

It supports four distinct I²C transfer modes: random read, current address read, sequential read, and two write modes - byte write and page write - all governed by SCL/SDA timing aligned to I²C specification (1 MHz max). The WC pin provides synchronous hardware-level write inhibition independent of software state, while the identification page (available in M24256-D variants) is not implemented in this BF-suffix part.

Key Specifications

Pinout & Package

Package: TSSOP8 (DW), 169 mil width, ECOPACK2-compliant, RoHS- and halogen-free.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Compared with AT24C256-SSHL-T and BR24G256FJ-WE2, the M24256-BFMC6TG uniquely combines hardware write protection, built-in ECC, and ECOPACK2 compliance in a TSSOP8 package - making it optimal for industrial and medical systems demanding both data integrity and regulatory conformance.

Availability

M24256-BFMC6TG is available at Aetrix Electronics and suitable for industrial PLCs, smart sensors, medical diagnostics equipment, and automotive body control modules requiring stable component supply across multi-year production cycles.

Supply support for M24256-BFMC6TG includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and memory solutions for industrial, automotive, and consumer markets.

The M24256 belongs to ST's serial EEPROM product line, engineered specifically for robust, low-power, I²C-based nonvolatile data storage in space-constrained and mission-critical embedded systems.

FAQ

What is the function of the WC pin on M24256-BFMC6TG?

The WC (Write Control) pin is an active-high hardware lock that disables all write operations to the entire 256-Kbit memory array when driven high. It does not affect read operations. This feature prevents accidental or malicious overwrites during power-up/down sequences, brownouts, or firmware glitches - eliminating reliance on software-only protection schemes.

Does M24256-BFMC6TG support the identification page feature?

No. The identification page (a 64-byte write-lockable area) is exclusive to M24256-D order codes (e.g., M24256-DF). The M24256-BFMC6TG uses the "BF" suffix, indicating the base version without identification page functionality. Only standard 32 Kbyte memory array and its associated I²C commands are supported.

Can M24256-BFMC6TG operate reliably at 1.7 V with 1 MHz I²C clock?

Yes. Per DS1766 Rev 35, the M24256-BF variant (including BFMC6TG) is fully specified for 1 MHz I²C operation across the full 1.7 V to 5.5 V VCC range. All AC timing parameters - including tBUF, tHD:STA, tSU:STA, and tLOW - meet I²C Fast-mode Plus requirements at 1.7 V, validated across −40 °C to +85 °C.

How does the ECC feature impact memory endurance and usage?

ECC operates transparently on 4-byte groups: a single-bit error in any byte of the group is corrected on read. When writing one byte, ECC logic also writes the other three bytes in the same group, distributing wear. Thus, endurance is budgeted per 4-byte group - the sum of writes to all four bytes must stay below 4 million cycles. Designers should avoid repeatedly writing to adjacent addresses within the same group to maximize lifespan.