The FM25L04B-DG is a 4-Kbit (512 × 8) nonvolatile ferroelectric RAM (F-RAM) with a high-speed SPI interface up to 20 MHz, supporting SPI modes 0 and 3. It delivers 100 trillion (1×10¹⁴) read/write cycles and 151-year data retention, surpassing serial flash and EEPROM in write speed and endurance.