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Home > Products > Integrated Circuits (ICs) > Memory > Memory

Infineon Technologies FM25640B-G

Name: FM25640B-G
Brand: Infineon Technologies
SKU: FM25640B-G
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: FM25640B-G

Manufacturer:: Infineon Technologies

Category:: Memory

Package:: 8-SOIC (0.154", 3.90mm Width)

Datasheet:: FM25640B-G.pdf

Description:: IC FRAM 64KBIT SPI 20MHZ 8SOIC

Quantity:: RFQ Add To RFQ list

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Inventory:2,156

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Product details

Overview

FM25640B-G from Infineon Technologies (formerly Cypress) is a 64-Kbit serial SPI F-RAM organized as 8K × 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 and flash in industrial control and data logging systems.

For engineers reviewing the FM25640B-G datasheet, FM25640B-G pinout, FM25640B-G application, or FM25640B-G equivalent, key selection criteria include write-cycle speed without polling, guaranteed industrial temperature operation (–40 °C to +85 °C), SOIC-8 package compatibility, and hardware/software write protection via WP pin and status register.

Technical Context

The FM25640B-G implements ferroelectric memory technology enabling true RAM-like write behavior with nonvolatile retention. Its internal architecture includes an 8K × 8 F-RAM array, 3-bit status register with WPEN control, and dedicated instruction decoder supporting WREN, WRDI, RDSR, WRSR, READ, and WRITE opcodes.

It operates exclusively as an SPI slave device with synchronous full-duplex communication. All data transfers use MSB-first format; address fields are 13-bit with upper 3 bits ignored. The HOLD pin enables transaction suspension without clock or CS dependency, provided transitions occur only when SCK is LOW.

Key Specifications

Parameter	Value and Actual Design Meaning
Memory Size	64 Kbit (8,192 × 8 bytes); enables byte-level random access without page erase overhead
SPI Speed	Up to 20 MHz; supports real-time data capture at bus speed without wait states
Endurance	10¹⁴ read/write cycles; eliminates wear leveling firmware in high-write-rate applications
Data Retention	151 years at +85 °C; ensures long-term reliability without refresh or backup power
Supply Voltage	4.5 V to 5.5 V; compatible with legacy 5 V microcontroller I/O domains
Operating Temp	–40 °C to +85 °C; qualified for industrial automation and metering environments
Active Current	250 µA at 1 MHz; reduces system power budget during frequent memory access

Pinout & Package

FM25640B-G is housed in an 8-pin Small Outline Integrated Circuit (SOIC) package with standard 150-mil body width and 1.27 mm pitch.

Pin/Terminal	Circuit Role	Design Meaning
CS	Chip Select input	Active-low enable; places device in standby (4 µA) when HIGH; initiates opcode decoding on falling edge
SCK	Serial clock input	Synchronizes all I/O; inputs latched on rising edge, outputs driven on falling edge
SI	Serial input	Receives opcodes, addresses, and write data; must be held valid during active CS to meet IDD spec
SO	Serial output	Drives read data and status register contents; tristated when CS HIGH or HOLD LOW
WP	Write protect input	Hardware lock for status register when WPEN = 1; must be tied to VDD if unused
HOLD	Transaction suspend input	Pauses ongoing read/write without losing internal state; requires SCK LOW during transition
VSS	Ground	Reference return path for all internal circuitry and I/O drivers
VDD	Power supply	5 V nominal supply; powers core logic, F-RAM array, and I/O buffers

Key Features

Feature	Design Value
NoDelay™ write execution	Writes complete within one SPI byte transfer; no polling or timeout handling required in host firmware
Hardware + software write protection	Combines WP pin control with software-configurable block protection (1/4, 1/2, or full array)
SPI mode compatibility	Supports both Mode 0 (CPOL=0, CPHA=0) and Mode 3 (CPOL=1, CPHA=1) for broad MCU interoperability
Low-power standby	4 µA typical current draw when CS HIGH; enables energy-efficient duty-cycled data logging
Ferroelectric process reliability	Eliminates charge-pump circuits and erase cycles; avoids flash/EEPROM failure mechanisms under thermal stress

Applications

Industrial Data Logger

Smart Energy Meter

Use Scenario: Continuous timestamped sensor sampling at 100 Hz with power-loss resilience.

IC Role / Device Role / Timing Role: Nonvolatile scratchpad storing last valid readings and calibration constants between mains cycles.

Use Value: 10¹⁴ endurance prevents wear-out over 10+ years of sub-second writes; 151-year retention guarantees data integrity across product lifetime.

Use Scenario: Tamper-event logging and tariff parameter storage in utility-grade electricity meters.

IC Role / Device Role / Timing Role: Secure configuration memory holding billing algorithms and cryptographic keys with hardware write lock.

Use Value: WP pin + status register protection prevents unauthorized firmware modification; 5 V operation matches meter ASIC I/O voltage.

PLC I/O Module

Medical Diagnostic Recorder

Use Scenario: Storing real-time I/O state history and fault codes in programmable logic controllers.

IC Role / Device Role / Timing Role: High-speed buffer for cyclic process data snapshots synchronized to 1 ms control loop.

Use Value: 20 MHz SPI enables full 8K read in <1 ms; eliminates flash write latency that could delay safety-critical diagnostics.

Use Scenario: Capturing ECG waveform segments during battery-powered portable diagnostics.

IC Role / Device Role / Timing Role: Low-power nonvolatile buffer acquiring analog samples without external backup capacitors.

Use Value: 250 µA active current at 1 MHz extends battery life; zero-write-delay ensures no sample loss during unexpected shutdown.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
AT25DF041A-SSH-T	4 Mbit serial NOR flash; requires 25 ms sector erase before write; 100k endurance	Lacks true byte-write capability; unsuitable for sub-millisecond update rates	Select only if cost-per-bit is primary and write frequency is <100x/day
BR24G64FJ-WE2	64 Kbit I²C EEPROM; 1 MHz max interface; 1M endurance; 40 µs write time per byte	Slower interface and lower endurance limit continuous logging duration	Prefer for space-constrained designs where I²C bus is already present and write rate is low

Compared with AT25DF041A-SSH-T and BR24G64FJ-WE2, FM25640B-G delivers deterministic sub-microsecond write latency, 100 million × higher endurance, and seamless SPI drop-in compatibility-making it uniquely suited for high-frequency, mission-critical nonvolatile storage.

Availability

FM25640B-G is available at Aetrix Electronics and suitable for industrial data loggers, smart energy meters, PLC I/O modules, and medical diagnostic recorders requiring stable component supply and long-term obsolescence support.

Supply support for FM25640B-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

Infineon Technologies is a global semiconductor leader headquartered in Munich, Germany, specializing in power management, automotive, industrial, and security solutions.

The FM25640B-G belongs to Infineon's F-RAM product line, engineered specifically to replace serial flash and EEPROM in applications demanding rapid, reliable, and low-power nonvolatile writes without firmware complexity.

FAQ

Is FM25640B-G pin-compatible with standard SOIC-8 SPI EEPROMs?

Yes-FM25640B-G uses identical 8-pin SOIC packaging and matches the pinout of industry-standard SPI EEPROMs (CS, SCK, SI, SO, WP, HOLD, VSS, VDD). No PCB redesign is needed for drop-in replacement, though firmware must be updated to remove write polling loops due to NoDelay™ operation.

Does FM25640B-G require external high-voltage programming circuitry?

No-FM25640B-G performs all write operations at standard VDD (4.5–5.5 V) without charge pumps or elevated voltages. This eliminates external HV generators, reduces board area, and improves system reliability compared to EEPROM and flash devices requiring >10 V for programming.

How does the HOLD pin behave during an active write operation?

When HOLD is pulled LOW during a write, the FM25640B-G suspends the transaction immediately and holds internal state. SCK and CS are ignored until HOLD returns HIGH while SCK is LOW. Upon resumption, the device continues the same write from the exact byte position-no data corruption or restart required.

Can FM25640B-G operate reliably at 5.5 V supply with –40 °C ambient temperature?

Yes-the device is fully specified across the entire industrial range: VDD = 4.5 V to 5.5 V and T_A = –40 °C to +85 °C. Electrical characteristics including 20 MHz SPI timing, 4 µA standby current, and 10¹⁴ endurance are guaranteed at these extremes, with no derating required.

FM25640B-G Specifications

Product attributes: Attribute value

Manufacturer:: Infineon Technologies

Series:: F-RAM™

Package/Case:: 8-SOIC (0.154", 3.90mm Width)

Packaging:: Bulk

Product Status:: Active

Programmable:: Not Verified

Memory Type:: Non-Volatile

Memory Format:: FRAM

Technology:: FRAM (Ferroelectric RAM)

Memory Size:: 64Kbit

Memory Organization:: 8K x 8

Memory Interface:: SPI

Clock Frequency:: 20 MHz

Write Cycle Time - Word, Page:: -

Access Time:: -

Voltage - Supply:: 4.5V ~ 5.5V

Operating Temperature:: -40°C ~ 85°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 8-SOIC

FM25640B-G FAQ

1.How can I place an order for FM25640B-G through Aetrix?

Please submit a Request for Quotation (RFQ) for FM25640B-G on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for FM25640B-G reliable?

The price and inventory of FM25640B-G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FM25640B-G is usually 5 days.

3.What payment methods are accepted for FM25640B-G?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FM25640B-G transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for FM25640B-G?

FM25640B-G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your FM25640B-G order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for FM25640B-G?

For technical support, including FM25640B-G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FM25640B-G requirements.

6.How does Aetrix verify that FM25640B-G is sourced from the original manufacturer or authorized distributors?

All FM25640B-G products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that FM25640B-G meets industry standards.

7.What is the process for return or replacement of FM25640B-G?

All FM25640B-G units undergo pre-shipment inspection (PSI). If there is an issue with FM25640B-G, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The FM25640B-G part is unused and in its original packaging.

Return procedure for FM25640B-G:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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