Infineon Technologies FM25CL64B-GTR

Overview

FM25CL64B-GTR from Infineon Technologies (formerly Cypress) is a 64-Kbit serial SPI F-RAM organized as 8K × 8, delivering true RAM-like write performance with nonvolatile data retention. It supports up to 20 MHz SPI clock, operates from 2.7 V to 3.65 V, and guarantees 10¹⁴ read/write cycles with 151-year data retention at +85 °C - ideal for high-frequency data logging in industrial controllers.

For engineers reviewing the FM25CL64B-GTR datasheet, FM25CL64B-GTR pinout, FM25CL64B-GTR application, or FM25CL64B-GTR equivalent, key selection criteria include NoDelay™ write capability, hardware/software write protection (WP pin + status register), SPI Mode 0/3 compatibility, industrial temperature range (–40 °C to +85 °C), and drop-in replacement feasibility for serial EEPROM or flash in real-time data capture systems.

Technical Context

The FM25CL64B-GTR implements ferroelectric memory cell architecture enabling immediate byte-write without erase or polling. Its internal control logic handles opcode decoding, address latching, and status register management autonomously upon CS activation.

SPI interface compliance includes full Mode 0 (CPOL = 0, CPHA = 0) and Mode 3 (CPOL = 1, CPHA = 1) operation, with data sampled on SCK rising edge and output on falling edge. The HOLD pin suspends ongoing transfers synchronously when asserted low while SCK is low.

Key Specifications

Pinout & Package

FM25CL64B-GTR is available in two RoHS-compliant packages: 8-pin SOIC (3.9 mm × 4.9 mm) and 8-pin DFN (2 mm × 3 mm) with exposed pad (not connected).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MB85RS64V and AT25DF041A, FM25CL64B-GTR uniquely balances 20 MHz SPI speed, 3.3 V compatibility, 10¹⁴ endurance, and zero-write-delay - making it optimal for deterministic real-time data capture where timing predictability and longevity are non-negotiable.

Availability

FM25CL64B-GTR is available at Aetrix Electronics and suitable for industrial data loggers, smart metering systems, PLC I/O modules, and medical diagnostic devices requiring stable component supply across multi-year production cycles.

Supply support for FM25CL64B-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, specializing in power management, sensing, connectivity, and security solutions for industrial, automotive, and IoT markets.

The FM25CL64B-GTR belongs to Infineon's F-RAM product line, engineered specifically for applications demanding frequent, low-latency, and highly reliable nonvolatile data storage without flash overhead or EEPROM endurance limits.

FAQ

Is FM25CL64B-GTR pin-compatible with standard SPI EEPROMs like AT25xxx series?

Yes - FM25CL64B-GTR uses identical 8-pin SOIC/DFN footprints and SPI command set (WREN, WRDI, RDSR, WRSR, READ, WRITE) as industry-standard serial EEPROMs. Hardware replacement requires no PCB redesign, though firmware must disable polling loops due to NoDelay™ writes.

Does the HOLD pin require external pull-up resistors?

No - HOLD is internally pulled up to VDD. It may be left floating or tied directly to VDD if unused. Driving HOLD low during active SCK violates timing and may corrupt transfers; transitions must occur only while SCK is low.

Can FM25CL64B-GTR operate reliably at 2.7 V minimum supply?

Yes - all electrical specifications including 20 MHz SPI operation, 10¹⁴ endurance, and 151-year retention are guaranteed down to 2.7 V at –40 °C to +85 °C per datasheet Rev. *J. Below 2.7 V, VDD monitor may trigger internal reset, halting memory access.

What happens if WP pin is left unconnected?

Leaving WP floating risks unintended status register writes due to noise coupling. The datasheet mandates tying WP to VDD if unused. When WPEN bit = 1 in status register, WP pin actively blocks status register modification - critical for preventing accidental protection disable.