It uses an I2C serial interface running at up to 1 MHz, with a 550 ns access time that allows fast read/write cycles without the page-write delays typical of EEPROM. The non-volatile nature means data is retained without a backup battery, and the FRAM technology offers virtually unlimited write endurance — a key advantage over Flash or EEPROM for frequent data logging or configuration storage. Operating from a 2.7V to 3.6V supply, this part fits 3.3V logic systems directly.
550 ns access time — timing margin for the I2C bus
This is fast enough to avoid wait states in most microcontroller I2C peripherals, but the bus master must respect the minimum SCL low and high times specified in the I2C standard. For designs pushing the bus near its 1 MHz limit, the 550 ns access leaves about 450 ns of margin per byte — enough for typical firmware overhead. If the bus has multiple slaves or long traces, the margin shrinks; a scope check on the prototype is recommended.
The base product number FM24CL64 covers multiple package and tape options (the -DG suffix denotes the tube-packaged 8-DFN variant), so if your line prefers tape-and-reel, the FM24CL64B-GTR is the same die in cut-tape or reel form.