STMicroelectronics M24128X-FCU6T/TF

Overview

M24128X-FCU6T/TF from STMicroelectronics is a 128-Kbit (16 Kbyte) I²C-compatible serial EEPROM in a 4-ball WLCSP package, supporting 400 kHz and 1 MHz transfer rates, operating from 1.7 V to 5.5 V over –40 °C to +85 °C, with software-configurable device address and write protection - used for firmware parameter storage in space-constrained IoT sensor nodes.

For engineers reviewing the M24128X-FCU6T/TF datasheet, M24128X-FCU6T/TF pinout, M24128X-FCU6T/TF application, or M24128X-FCU6T/TF equivalent, key selection criteria include configurable I²C address (CDA), 32-byte page write capability, 4 million write cycles, 200-year data retention, and WLCSP footprint compatibility with high-density PCB layouts.

Technical Context

This EEPROM implements a standard I²C slave interface with SDA (open-drain I/O) and SCL (input-only) pins, requiring external pull-up resistors. It uses an internal HV generator and sequencer for byte/page programming without external voltage boosting.

The device integrates an 8-bit non-volatile chip enable register enabling up to eight unique I²C addresses (C2–C0 bits) and software write protection (SWP bit). Address decoding and ACK/NACK response are fully hardware-managed per I²C protocol timing requirements.

Key Specifications

Pinout & Package

Delivered in a RoHS- and halogen-free 4-ball WLCSP (Wafer-Level Chip Scale Package), measuring 1.19 mm × 1.19 mm × 0.53 mm (max), with bottom-side bump layout optimized for minimal PCB footprint and thermal performance in ultra-thin applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C128C-SSHL-T and BR24G128FJ-WE2, the M24128X-FCU6T/TF uniquely combines WLCSP packaging, 1 MHz I²C, and software-defined addressing - enabling higher node density and simplified firmware-driven bus arbitration in next-gen miniaturized systems.

Availability

M24128X-FCU6T/TF is available at Aetrix Electronics and suitable for smart wearables, industrial PLC modules, and medical infusion pumps requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for M24128X-FCU6T/TF 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 management ICs, sensors, and memory solutions for industrial, automotive, and consumer markets.

The M24128X-FCU6T/TF belongs to ST's M24 serial EEPROM product line, engineered specifically for ultra-compact, high-reliability applications demanding configurable I²C addressing, extended voltage operation, and robust data retention in harsh environments.

FAQ

What is the maximum I²C clock frequency supported by the M24128X-FCU6T/TF?

The device supports standard-mode (400 kHz) and fast-mode (1 MHz) I²C operation. Fast-mode timing compliance is verified per I²C specification with tLOW ≥ 0.6 μs and tHIGH ≥ 0.6 μs at VCC ≥ 2.5 V. No external clock stretching is required - all timing is managed internally.

How is the configurable device address (CDA) programmed and retained?

The CDA is stored in a dedicated 8-bit non-volatile chip enable register. Bits C2–C1–C0 are written using a special address (A15 = 1, A14–A0 = don't care) and persist across power cycles. Factory default is 000b, and values are loaded at power-up from the last successfully written state.

Does the M24128X-FCU6T/TF require external components for basic operation?

Yes: an external pull-up resistor on SDA (and optionally SCL) is mandatory per I²C specification. A 10–100 nF ceramic decoupling capacitor between VCC and VSS is required near the package to stabilize supply during internal write cycles and ensure reliable 5 ms programming.

Can the software write protection (SWP) bit be toggled multiple times in the field?

Yes - the SWP bit is fully reversible: writing '0' enables writes; writing '1' disables them. The change takes effect immediately after the internal write cycle completes. No hardware WP pin or power cycle is needed, enabling dynamic lockdown/unlock in certified medical or industrial firmware updates.