Infineon Technologies FM24C04B-G

Overview

FM24C04B-G from Cypress Semiconductor is a 4-Kbit (512 × 8) serial I²C ferroelectric RAM (F-RAM) nonvolatile memory IC, functioning as a direct hardware replacement for I²C EEPROM in system-level data logging and configuration storage. It delivers NoDelay™ writes, 100 trillion (10¹⁴) read/write endurance, and 151-year data retention at industrial temperatures (–40 °C to +85 °C), operating from 4.5 V to 5.5 V in an 8-pin SOIC package.

For engineers reviewing the FM24C04B-G datasheet, FM24C04B-G pinout, FM24C04B-G application, or FM24C04B-G equivalent, key selection criteria include write-cycle speed without polling, endurance margin over EEPROM, I²C timing compatibility at 1 MHz, and AEC-Q100 Grade 3 qualification for automotive-adjacent industrial control systems.

Technical Context

The FM24C04B-G implements a true nonvolatile RAM architecture using ferroelectric capacitor-based memory cells, enabling byte-level writes at full I²C bus speed with zero write latency. Its internal address latch supports 9-bit addressing (8-bit word + 1-bit page select), allowing seamless access across two 256-byte pages without software overhead.

It operates strictly as an I²C slave device with fixed 7-bit slave address prefix 1010b, configurable device-select bits (A2/A1), and R/W bit-driven transaction mode. The SDA/SCL interface incorporates Schmitt-trigger inputs and slope-controlled outputs, ensuring robust noise immunity and signal integrity at up to 1 MHz clock frequency.

Key Specifications

Pinout & Package

FM24C04B-G is housed in an 8-pin Small Outline Integrated Circuit (SOIC) package with gull-wing leads, 1.27 mm pitch, and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C04D-SSHM-T and MB85RC04V, FM24C04B-G uniquely balances AEC-Q100 Grade 3 qualification, 1 MHz I²C performance, and hardware write protection in a pin-identical SOIC footprint - making it optimal for industrial control upgrades requiring zero firmware change.

Availability

FM24C04B-G is available at Aetrix Electronics and suitable for industrial data loggers, automotive telematics modules, smart meter firmware configuration, and medical infusion pump calibration requiring stable component supply and long-term lifecycle assurance.

Supply support for FM24C04B-G 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

Cypress Semiconductor (now part of Infineon Technologies) designs high-reliability nonvolatile memory and programmable system-on-chip solutions for automotive, industrial, and IoT applications.

The FM24C04B-G belongs to Cypress's F-RAM product line, engineered specifically to replace EEPROM in high-write-frequency, low-power, and mission-critical embedded systems where data integrity and timing predictability are essential.

FAQ

Is FM24C04B-G pin-compatible with standard I²C EEPROMs like AT24C04?

Yes - FM24C04B-G uses an identical 8-pin SOIC package and matches the pin functions (A1/A2, SDA, SCL, WP, VDD, VSS) of AT24C04-series EEPROMs. Its slave address structure (1010b prefix + A2/A1 bits) is fully compatible, enabling direct hardware replacement without PCB redesign.

Does FM24C04B-G require external pull-up resistors on SDA and SCL lines?

Yes - SDA and SCL are open-drain outputs requiring external pull-up resistors to VDD. Recommended values are 2.2 kΩ for 100 kHz, 1 kΩ for 400 kHz, and 4.7 kΩ for 1 MHz operation, based on bus capacitance and rise-time requirements specified in the datasheet.

How does the WP pin function, and what happens when it is left floating?

The WP pin is internally pulled down; leaving it unconnected defaults to write-enable mode. Tying WP to VDD activates full-memory write protection. Floating WP is electrically safe but not recommended - unintended noise coupling could cause intermittent protection failure in noisy industrial environments.

Can FM24C04B-G operate reliably at 5.5 V supply with 1 MHz I²C clock?

Yes - the device is fully characterized for 4.5 V to 5.5 V operation and supports 1 MHz I²C timing across the entire voltage and temperature range (–40 °C to +85 °C). AC switching characteristics in the datasheet confirm setup/hold times and pulse widths remain compliant at VDD = 5.5 V.