STMicroelectronics M24C64-WMN6P

Overview

M24C64-WMN6P from STMicroelectronics is a 64-Kbit I²C-compatible EEPROM organized as 8 K × 8 bits, operating from 2.5 V to 5.5 V over –40 °C to +85 °C. It supports 1 MHz, 400 kHz, and 100 kHz I²C bus modes, features 32-byte page write (≤5 ms), 4 million write cycles, and 200-year data retention. Used for configuration storage in industrial controllers, sensor calibration registers, and power-management parameter backup.

For engineers reviewing the M24C64-WMN6P datasheet, M24C64-WMN6P pinout, M24C64-WMN6P application, or M24C64-WMN6P equivalent, key selection criteria include supply voltage range (2.5–5.5 V), I²C speed compatibility (up to 1 MHz), write-protection via WC pin, page size (32 bytes), and SO8N ECOPACK2 packaging with verified pin mapping.

Technical Context

The device implements a standard I²C slave protocol with start/stop detection, 7-bit device addressing (with E2/E1/E0 chip enable inputs), and ACK/NACK handshaking. It uses internal address latching and auto-incrementing counters for sequential read/write operations.

Write control (WC) enables hardware-level memory lockout: when high, all write attempts are rejected with NoAck; when low or floating, byte and page writes proceed. The memory array includes ECC logic (process-dependent) for single-bit error correction per 4-byte group, improving long-term reliability without protocol overhead.

Key Specifications

Pinout & Package

Package: SO8N (ECOPACK2), 150 mil width, RoHS-compliant and halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C64D-SSHM-T and BR24G64FJ-WE2, M24C64-WMN6P offers guaranteed 2.5–5.5 V operation with robust hardware write protection, making it preferred for industrial environments where voltage stability and fault resilience are critical.

Availability

M24C64-WMN6P is available at Aetrix Electronics and suitable for industrial PLCs, smart sensors, power supply sequencers, and medical device settings backup requiring stable component supply across extended production lifecycles.

Supply support for M24C64-WMN6P 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, analog ICs, power devices, and memory solutions for industrial, automotive, and consumer markets.

The M24Cxx series targets cost-sensitive, high-reliability embedded systems requiring serial EEPROM with industrial-grade voltage tolerance, extended temperature operation, and hardware write protection - optimized for factory-programmed configuration storage.

FAQ

What is the function of the WC pin on M24C64-WMN6P?

The WC (Write Control) pin is an active-high hardware lock that disables all write operations to the entire memory array when driven high. When low or floating, writes proceed normally. This provides deterministic protection against accidental overwrites during power-up, brown-out, or firmware errors - independent of I²C command execution.

Can M24C64-WMN6P operate at 3.3 V and interface directly with a 3.3 V microcontroller?

Yes. M24C64-WMN6P operates from 2.5 V to 5.5 V over –40 °C to +85 °C, fully covering standard 3.3 V logic levels. Its SDA/SCL pins are open-drain with I²C-compliant voltage thresholds, enabling direct connection to 3.3 V MCUs without level shifters - provided the pull-up resistors reference the same 3.3 V supply.

How does page write work, and what is the maximum number of bytes per transaction?

Page write allows up to 32 bytes to be written in a single I²C transaction, constrained to addresses within the same 32-byte page boundary (A15–A5 unchanged). If more than 32 bytes are sent, wraparound occurs within the page. Each page write completes in ≤5 ms, and the internal address counter increments automatically after the stop condition.

Is ECC (Error Correction Code) enabled in M24C64-WMN6P, and how does it affect usage?

ECC is implemented only in devices marked with process letter 'K' - not guaranteed for all M24C64-WMN6P units. When present, it corrects single-bit errors per 4-byte group transparently during reads. Writes to any byte in a group also cycle the other three bytes, distributing endurance across the group - requiring design-level awareness of grouped wear for high-write applications.