Infineon Technologies FM25W256-GTR

Overview

FM25W256-GTR from Infineon Technologies (formerly Cypress) is a 256-Kbit serial SPI F-RAM organized as 32K × 8, featuring NoDelay™ writes, 10¹⁴ read/write endurance, and 151-year data retention. It operates at up to 20 MHz SPI clock, supports modes 0 and 3, and functions as a hardware drop-in replacement for serial EEPROM or flash in real-time data logging systems.

For engineers reviewing the FM25W256-GTR datasheet, FM25W256-GTR pinout, FM25W256-GTR application, or FM25W256-GTR equivalent, key selection criteria include write latency tolerance, industrial temperature operation (–40 °C to +85 °C), SOIC-8 package compatibility, and SPI bus timing alignment with legacy EEPROM/flash interfaces.

Technical Context

The FM25W256-GTR implements ferroelectric memory cells enabling true RAM-like write behavior without erase cycles or write delays. Its internal architecture includes a 32K × 8 nonvolatile array, a 3-bit status register with WPEN control, and dedicated hardware write protection via the active-low WP pin.

SPI interface logic handles opcode decoding (e.g., WREN, READ, WRITE), address latching (15-bit effective, MSB ignored), and synchronous I/O timing aligned to SCK rising/falling edges. The device requires no polling or busy-waiting - write completion is immediate upon byte transfer completion.

Key Specifications

Pinout & Package

FM25W256-GTR is housed in an 8-pin Small Outline Integrated Circuit (SOIC) package with standard 150-mil body width and gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25SF041-SSHD-B and MB85RS2MT-FPNSE, FM25W256-GTR uniquely delivers 10¹⁴ endurance with 151-year retention in a proven 256-Kbit footprint-making it optimal for mission-critical, high-write industrial logging where long-term data integrity is non-negotiable.

Availability

FM25W256-GTR is available at Aetrix Electronics and suitable for industrial data loggers, smart energy meters, PLC I/O modules, and automotive body controllers requiring stable component supply, guaranteed RoHS compliance, and long-lifecycle support.

Supply support for FM25W256-GTR 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

Infineon Technologies is a global semiconductor leader headquartered in Munich, Germany, delivering power systems, sensors, and memory solutions for industrial, automotive, and IoT applications.

FM25W256-GTR belongs to Infineon's F-RAM portfolio, engineered specifically for applications demanding ultra-high endurance, instant writes, and long-term data retention without battery backup or complex firmware management.

FAQ

Is FM25W256-GTR pin-compatible with standard SPI EEPROMs like AT25XXX series?

Yes - FM25W256-GTR uses an industry-standard 8-pin SOIC package with identical pinout (CS, SCK, SI, SO, WP, HOLD, VSS, VDD) and SPI command set (READ, WRITE, WREN, etc.). No PCB redesign is needed for drop-in replacement, though firmware may omit polling loops due to NoDelay™ writes.

Does FM25W256-GTR require external high-voltage programming or special write sequences?

No - FM25W256-GTR performs writes at standard VDD levels (2.7–5.5 V) with no high-voltage pump or multi-cycle programming. A single SPI WRITE command followed by data bytes commits data instantly; no erase, verify, or delay sequences are required.

How does the HOLD pin function during an active memory operation?

When HOLD is pulled LOW during any SPI transaction (read or write), the FM25W256-GTR suspends communication immediately: SCK and CS are ignored, and SO enters high-impedance. Operation resumes on next SCK edge after HOLD returns HIGH - preserving address and data state without corruption.

Can FM25W256-GTR operate reliably at 5.5 V while maintaining full 20 MHz SPI performance?

Yes - the device is fully specified for DC and AC operation across 2.7–5.5 V. At VDD = 5.5 V, t_CLK (min) remains 50 ns (20 MHz), and all timing parameters including setup/hold margins meet datasheet limits without derating.