Adafruit SPI FRAM Breakout Boards are non-volatile chips that are designed for lower power usage and faster write performances. These FRAM boards feature a Serial Peripheral Interface (SPI) interface, 40MHz clock rates, and each byte can be read/written 10,000,000,000,000 times without worrying about wear leveling. The FRAM chip operates at -40°C to 85°C ambient temperature range and is available in 2Mbit (256KB) and 4Mbit (512KB) storage options. These breakout boards feature a 3.3V logic level shifting and a regulator that can be used with 3V and 5V power and logic.
Correspondent to SPI mode 0 (0, 0) and mode 3 (1, 1)