Infineon Technologies FM25L16B-DG

Overview

FM25L16B-DG from Infineon Technologies (formerly Cypress) is a 16-Kbit serial SPI F-RAM organized as 2K × 8, functioning as a nonvolatile memory replacement for EEPROM and serial flash in real-time data logging systems. It delivers NoDelay™ writes at up to 20 MHz SPI clock rate, supports industrial temperature (–40 °C to +85 °C), operates from 2.7 V to 3.6 V, and guarantees 10¹⁴ read/write cycles with 151-year data retention.

For engineers reviewing the FM25L16B-DG datasheet, FM25L16B-DG pinout, FM25L16B-DG application, or FM25L16B-DG equivalent, key selection criteria include write endurance, zero-write-latency operation, SPI mode 0/3 compatibility, hardware/software write protection, and SOIC-8/DFN-8 package options for space-constrained industrial controllers and metering devices.

Technical Context

The FM25L16B-DG implements ferroelectric memory technology to eliminate write latency-data commits immediately upon byte transfer without polling or erase cycles. Its internal architecture includes a 2K × 8 F-RAM array, 3-bit nonvolatile status register, and dedicated instruction decoder supporting WREN, WRDI, RDSR, WRSR, READ, and WRITE opcodes.

It operates as an SPI slave in Mode 0 (CPOL = 0, CPHA = 0) and Mode 3 (CPOL = 1, CPHA = 1), with inputs latched on SCK rising edge and outputs driven on falling edge. The HOLD pin enables transaction suspension without clock or CS interference, and the WP pin provides hardware-level status register write lock when WPEN = 1.

Key Specifications

Pinout & Package

FM25L16B-DG is available in an 8-pin SOIC package (3.9 mm × 4.9 mm) with standard gull-wing leads and RoHS-compliant matte tin finish. Pin functions are electrically identical across SOIC and DFN variants; DFN variant includes an unconnected exposed pad not to be soldered.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MB85RS16 and AT25SF041, FM25L16B-DG uniquely balances ultra-high endurance, zero-write-latency, and industrial temperature reliability in a 16 Kbit footprint-making it optimal for applications where write frequency, determinism, and long-term data integrity outweigh raw density or peak bandwidth needs.

Availability

FM25L16B-DG is available at Aetrix Electronics and suitable for smart metering, industrial PLC data logging, medical diagnostic storage, and automotive telematics requiring stable component supply over extended product lifecycles.

Supply support for FM25L16B-DG 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 management, sensing, connectivity, and security solutions for industrial, automotive, and IoT markets.

The FM25L16B-DG belongs to Infineon's F-RAM portfolio-designed specifically for mission-critical nonvolatile data capture where write endurance, speed, and reliability surpass conventional flash and EEPROM in harsh or high-frequency update environments.

FAQ

Is FM25L16B-DG pin-compatible with standard SPI EEPROMs like AT25XXX series?

Yes-FM25L16B-DG uses identical 8-pin SOIC/DFN footprints and matches the SPI command set (READ, WRITE, WREN, RDSR) of AT25080A/AT25160B, including same opcode values and address format. Hardware replacement requires no PCB change, though WP and HOLD pins offer enhanced functionality not present in basic EEPROMs.

Does FM25L16B-DG require external high-voltage programming pulses or erase cycles?

No-FM25L16B-DG performs true random-access byte writes at bus speed with no erase prerequisite, no high-voltage pump, and no timeout delays. Each write completes within one SPI byte transfer window (e.g., ~400 ns at 20 MHz), eliminating firmware wait loops and wear-leveling logic.

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

When HOLD is pulled LOW during a write, the FM25L16B-DG immediately suspends the ongoing byte transfer-latching the current address and data state-and enters a quiescent hold mode. SCK and CS are ignored until HOLD returns HIGH, at which point the suspended operation resumes from the exact bit position without data corruption or retransmission.

Can FM25L16B-DG be used in 3-wire SPI configurations?

Yes-the SI and SO pins can be wired together (with appropriate series resistor or tri-state control) to implement a single-data-line SPI interface. The device supports this mode per datasheet Note 1; WP and HOLD must be tied to VDD, and software must manage direction control to avoid bus contention during readback.