The Cypress (Infineon) FM25H20-DG is a 2Mbit ferroelectric RAM organized as 256K x 8, accessed over an SPI bus at up to 40 MHz. FRAM combines non-volatility with fast, unlimited write endurance — no wear-leveling needed, no write-cycle budget to manage.
That means Cypress (Infineon) has ended production; no last-time-buy window remains. Stock that exists today is fixed — once it is consumed, the part is gone. Any new design should avoid this order code unless the board is already locked and the program life is short enough to cover with known inventory.
40 MHz SPI — throughput and bus timing
The 40 MHz SPI clock translates to a theoretical read throughput of 5 Mbytes/s in single-I/O mode. That is fast enough to shadow firmware images or stream sensor data into a circular buffer without stalling the host MCU. The FRAM's zero-write-delay characteristic means every byte written at 40 MHz takes the same time as a read — no page-program wait states. For designs that log at high rates or need atomic byte writes, this avoids the latency jitter that NAND or NOR Flash introduces.
Package and footprint — 8-WDFN exposed pad
The FM25H20-DG is supplied in an 8-WDFN with exposed pad, measuring 5 mm x 6 mm (supplier device package 8-DFN). Surface-mount reflow per the standard WDFN profile applies; The tube shipping medium means pick-and-place feeders may need a tube-to-tape conversion or manual handling for low-volume builds.