STMicroelectronics M24256E-FDW6TP

Overview

M24256E-FDW6TP from STMicroelectronics is a 256-Kbit I²C-compatible EEPROM organized as 32 K × 8 bits, featuring configurable and preprogrammed device addressing, hardware write protection via WC pin, and operation across 1.6 V–5.5 V supply at -40 °C to +85 °C. It supports Fast-mode Plus (1 MHz), Fast-mode (400 kHz), and Standard-mode (100 kHz) I²C bus speeds, with 64-byte page writes and an additional 64-byte identification page for secure parameter storage in industrial sensor calibration and embedded system configuration.

For engineers reviewing the M24256E-FDW6TP datasheet, M24256E-FDW6TP pinout, M24256E-FDW6TP application, or M24256E-FDW6TP equivalent, key selection considerations include its configurable device address register (CDA), hardware write control (WC) input, 5 ms typical byte/page write time, and ECOPACK2-compliant SO8N/TSSOP8/UFDFPN8/UFDFPN5 packaging options for space-constrained PCB layouts.

Technical Context

The M24256E-FDW6TP implements a dedicated I²C target interface with open-drain SDA and input SCL, requiring external pull-up resistors. Its internal architecture includes a high-voltage generator and sequencer for EEPROM programming, ECC logic for data integrity, and separate address latches for memory array, CDA register, and identification page access.

Device addressing uses a 7-bit slave address formed by fixed "1010" prefix plus three configurable C2–C0 bits from the CDA register (or factory-programmed values), with RW bit determining read/write direction. The WC pin provides hardware-level write inhibition independent of software lock states, enabling dual-layer protection for critical configuration data.

Key Specifications

Pinout & Package

Package: UFDFPN8 (2 mm × 3 mm, ECOPACK2-compliant). This 8-pin DFN variant features exposed thermal pad for improved power dissipation in compact industrial modules and automotive body control units.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C256B-SSHL-T and BR24G256FJ-3GE2, the M24256E-FDW6TP uniquely combines configurable I²C addressing, hardware WC pin, and a dedicated lockable ID page - making it optimal for scalable multi-node systems requiring field-programmable identity and robust configuration security.

Availability

M24256E-FDW6TP is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and smart energy metering requiring stable component supply across extended product lifecycles.

Supply support for M24256E-FDW6TP 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 microcontrollers, power ICs, sensors, and memory products for industrial, automotive, and consumer markets.

The M24256E-FDW6TP belongs to ST's serial EEPROM product line, engineered specifically for robust, low-power, and secure nonvolatile data storage in harsh environments where long-term reliability and flexible I²C integration are mandatory.

FAQ

What is the function of the WC pin on the M24256E-FDW6TP?

The WC (Write Control) pin is an active-high hardware input that globally disables all write operations-including memory array, configurable device address (CDA), and identification page writes-regardless of software lock status. When driven high, it forces NO ACK on data bytes and prevents inadvertent modification during power-up transients or field service. It operates independently of the CDA register's DAL bit, providing fail-safe protection layer.

Can the configurable device address (CDA) be changed after initial programming?

Yes, but only if the Device Address Lock (DAL) bit remains set to 0. While DAL = 0, the C2/C1/C0 bits can be rewritten via the "Write Configurable Device Address" instruction using I²C protocol with device type identifier 1011 and MSB address bits 110. Once DAL is set to 1-either by software command or factory preprogramming-the CDA register becomes permanently read-only and cannot be altered, even if WC is low.

How does the identification page differ from standard memory pages?

The identification page is a dedicated 64-byte area accessible via distinct I²C commands (device type identifier 1011, A10 = 0), separate from main memory addressing. It supports independent read/write and can be permanently locked to read-only mode using the "Identification Page Lock" command (A10 = 1). Unlike main memory, locked ID page writes return NO ACK, ensuring tamper resistance for calibration data, serial numbers, or cryptographic keys.

Which package variants are supported by the M24256E-FDW6TP part number?

The M24256E-FDW6TP specifically denotes the UFDFPN8 (2 mm × 3 mm) package with ECOPACK2 environmental compliance. Other variants include SO8N (150 mil), TSSOP8 (169 mil), and UFDFPN5 (1.7 mm × 1.4 mm), each assigned distinct suffixes (e.g., M24256E-FMN6TP for SO8N). Pinouts differ across packages-UFDFPN8 uses pins 1–4 (SDA, VSS, SCL, WC) and pins 7 (VCC), while TSSOP8 places VCC at pin 8 and adds NCs at pins 5–6.