FRAM® Ferroelectric RAM Technology
What is FRAM?
FRAM (ferroelectric random access memory) is a non-volatile memory that uses ferroelectric film as a capacitor for storing data. Possessing characteristics of both ROM and RAM devices, FRAM features high speed access, high endurance in write mode, low power consumption, non-volatility, and excellent tamper resistance. It is therefore ideal for use in smart cards, where high security and low power consumption are important, as well as in cellular phones and other devices.
What is Ferroelectric material?
PZT (Pb (ZrTi)O3) material which has a perovskite-type structure (ABO3), is commonly used as a typical ferroelectric material. When an electric field is applied the Zr/Ti atom shifts up or down, and this polarisation remains when the electric field is removed. It is this property that provides non-volatility and keeps the power required for data storage very low.
Crystal structure of Ferroelectric material
Characteristics of FRAM (Comparison with EEPROM)
Write time
Writing time of a single byte of data on FRAM is 30,000 times quicker than EEPROM.
Note: FRAM write cycle time is short enough to be ignored. Baud rate limits the transaction time. EEPROM write cycle time limits its transaction time.
Energy Consumption
Energy consumption of FRAM is 1/20 or less that of EEPROM.
Note: FRAM current consumption is estimated for low-power Smart Card applications.
Endurance
Endurance of FRAM is 100,000 times that of EEPROM
Features of FRAM
Currently, EEPROM is mainly used for data memory in Smart cards. However, FRAM is superior to EEPROM in terms of speed, power consumption, and high endurance in write mode. Compared with EEPROM, Fujitsu’s FRAM has the following features:
- 1/30,000 high-speed write time
- 1/400 or less power consumption
- 100,000 times or more rewrite capability (count)
