c29 - non-volatile random-access memory fram (ferroelectric ram)

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Non-Volatile Random-Access Memory FRAM (Ferroelectric RAM) Page 1 of 2 FRAM has what it takes to become the non-volatile memory of the future and to supersede both Flash and E 2 PROM. With its low power consumption, the technology combines the benefits of conventional non-volatile memories and rapid static RAM. Features Fast writing speed. Overwriting (no need to erase), Write Cycle=Read Cycle (no delay) High endurance. Guaranteed up to 1 trillion cycles High tamper resistance. Data written in FRAM cannot be stolen by physical analysis Low power consumption Ecology memory. Operating like SRAMs, with no requirement for battery back-up Applications Factory automation Metering Data logging Parameter storage Back-up memory Real-time data writing FRAM technology In contrast to the conventional non-volatile memories, Flash and E 2 PROM, the content of a FRAM cell is not stored in the form of charge carriers in a ‘floating gate’. The information – logically 0 or 1 – is contained in the polarisation of the ferroelectric material lead zirconate titanate, PZT (Pb (ZrTi)O 3). This material, is placed between two electrodes in the form of a thin film, in a similar way to the structure of a capacitor. A FRAM memory cell has the same structure as a DRAM cell and consists of a transistor and a capacitor, but in this case the FRAM cell contains a capacitor with a ferroelectric dielectric. Since no large charge quantities have to be displaced, charge pumps, used to generate higher programming voltages, are not necessary. Consequently, FRAM technology is much more energy-efficient than Flash or E 2 PROM. Write and Read access times are in the 2-3 digit nanosecond range and comparable with those of RAM. FRAM combines the benefits of non-volatile memories with those of static RAM. A by- product, so to speak, is a high resistance to radiation because, unlike with floating gate memories, alpha, beta and gamma radiation cannot harm the stored data. FRAM is therefore very well suited for medical or space-science applications, or applications in the food industry in which radiation can be used for disinfection. The maximum number of write/delete cycles for Flash and E 2 PROM is between 10,000 and 100,000. If this limit is exceeded, the memory content can no longer be reliably stored. If the content of a memory cell has to be updated once per second, for example, this limit is reached after only one day. By comparison with over 10 thousand million write/delete cycles (10 10 ), the lifetime of FRAM memory is almost unlimited. Writing could theoretically take place on a cell for over 300 years at one-second intervals. However, as read processes involve a re-programming of the FRAM cell, read accesses also have to be included in the total. The latest FRAM products are internally operated at 1.8V and specified up to 10 15 read/write cycles. Occasionally, FRAM is incorrectly associated with ferromagnetism. Magnetic fields do not affect the ferroelectric material. Fujitsu Semiconductor Europe Factsheet FRAM Stand-Alone Memory Products Line-up of Fujitsu standalone FRAM devices MB85R8xxx Parallel MB85R4001/2A Parallel MB85R1001/2A Parallel MB85R256F Parallel MB85RS256A Serial SPI MB85RS128A Serial SPI MB85RS64 Serial SPI MB85RS16 Serial SPI MB85RS256V Serial SPI MB85RS64V Serial SPI MB85RS16V Serial SPI MB85RS1xxx Serial SPI (1.8–3V) MB85RS2xxx Serial SPI (1.8–3V) MB85RC256V Serial I 2 C (3–5V) MB85RC128 Serial I 2 C MB85RC64 Serial I 2 C MB85RC16 Serial I 2 C MB85RC64V Serial I 2 C MB85RC16V Serial I 2 C 16Kb 8Mb 4Mb 2Mb 1Mb 256Kb 128Kb 64Kb Memory size (kbit) Planning and development Serial I 2 C 3V 5V 3V 1.8V 3V 5V Parallel I/F Serial SPI

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Page 1: C29 - Non-Volatile Random-Access Memory FRAM (Ferroelectric RAM)

Non-Volatile Random-Access MemoryFRAM (Ferroelectric RAM)

Page 1 of 2

FRAM has what it takes to become the non-volatile memory of the future and tosupersede both Flash and E2PROM. With itslow power consumption, the technologycombines the benefits of conventional non-volatile memories and rapid static RAM.

Features■ Fast writing speed. Overwriting (no need to

erase), Write Cycle=Read Cycle (no delay) ■ High endurance. Guaranteed up to 1 trillion

cycles■ High tamper resistance. Data written in

FRAM cannot be stolen by physical analysis■ Low power consumption■ Ecology memory. Operating like SRAMs,

with no requirement for battery back-up

Applications■ Factory automation■ Metering■ Data logging■ Parameter storage■ Back-up memory■ Real-time data writing

FRAM technologyIn contrast to the conventional non-volatilememories, Flash and E2PROM, the content ofa FRAM cell is not stored in the form of chargecarriers in a ‘floating gate’. The information –logically 0 or 1 – is contained in thepolarisation of the ferroelectric material leadzirconate titanate, PZT (Pb (ZrTi)O3). Thismaterial, is placed between two electrodes inthe form of a thin film, in a similar way to thestructure of a capacitor.

A FRAM memory cell has the same structureas a DRAM cell and consists of a transistor anda capacitor, but in this case the FRAM cellcontains a capacitor with a ferroelectricdielectric.

Since no large charge quantities have to bedisplaced, charge pumps, used to generatehigher programming voltages, are not

necessary. Consequently, FRAM technology ismuch more energy-efficient than Flash orE2PROM. Write and Read access times are inthe 2-3 digit nanosecond range andcomparable with those of RAM. FRAMcombines the benefits of non-volatilememories with those of static RAM. A by-product, so to speak, is a high resistance toradiation because, unlike with floating gatememories, alpha, beta and gamma radiationcannot harm the stored data. FRAM istherefore very well suited for medical orspace-science applications, or applications inthe food industry in which radiation can beused for disinfection. The maximum numberof write/delete cycles for Flash and E2PROM isbetween 10,000 and 100,000. If this limit isexceeded, the memory content can no longerbe reliably stored. If the content of a memorycell has to be updated once per second, forexample, this limit is reached after only oneday. By comparison with over 10 thousandmillion write/delete cycles (1010), the lifetime

of FRAM memory is almost unlimited. Writingcould theoretically take place on a cell for over300 years at one-second intervals. However,as read processes involve a re-programming of the FRAM cell, readaccesses also have to be included in the total.

The latest FRAM products are internallyoperated at 1.8V and specified up to 1015

read/write cycles. Occasionally, FRAM isincorrectly associated with ferromagnetism.Magnetic fields do not affect the ferroelectricmaterial.

Fujitsu Semiconductor Europe

Factsheet FRAM Stand-Alone MemoryProducts

Line-up of Fujitsu standalone FRAM devices

MB85R8xxxParallel

MB85R4001/2AParallel

MB85R1001/2AParallel

MB85R256FParallel

MB85RS256ASerial SPI

MB85RS128ASerial SPI

MB85RS64Serial SPI

MB85RS16Serial SPI

MB85RS256VSerial SPI

MB85RS64VSerial SPI

MB85RS16VSerial SPI

MB85RS1xxxSerial SPI (1.8–3V)

MB85RS2xxxSerial SPI (1.8–3V)

MB85RC256VSerial I2C (3–5V)

MB85RC128Serial I2C

MB85RC64Serial I2C

MB85RC16Serial I2C

MB85RC64VSerial I2C

MB85RC16VSerial I2C

16Kb

8Mb

4Mb

2Mb

1Mb

256K

b12

8Kb

64Kb

Mem

ory s

ize (k

bit)

Planning and development

Serial I2C

3V 5V 3V 1.8V 3V 5V

Parallel I/F Serial SPI

Page 2: C29 - Non-Volatile Random-Access Memory FRAM (Ferroelectric RAM)

Page 2 of 2

Factsheet Fujitsu FRAM Stand-Alone Memory Products

FSEU-C29-28FEB12

http://emea.fujitsu.com/fram

All company and product trade marks and registered trademarks used throughout this literature are acknowledged asthe property of their respective owners.

Part Number Availabilty Size Operating Write Cycle Operating Data PackageVoltage Time Temperature Retention

MB85R4001A Available 4Mbit 3.0 - 3.6V 150ns -40 - +85°C 10 years at 55°C TSOP-48MB85R4002A Available MB85R1001A Available 1Mbit 3.0 - 3.6V 150ns -40 - +85°C 10 years at 55°C TSOP-48MB85R1002A MB85R256F Available 256kbit 2.7 - 3.6V 150ns -40 - +85°C 10 years at 55°C TSOP-28

SOP-28

Parallel interface

Part Number Availabilty Size Operating Operating Operating Data PackageVoltage Frequency (Max) Temperature Retention

MB85RS256A Available 256kbit 3.0 - 3.6V 25MHz -40 - +85°C 10 years at 55°C SOP-8MB85RS128A Available 128kbit 3.0 - 3.6V 25MHz -40 - +85°C 10 years at 55°C SOP-8MB85RS64 Available 64kbit 2.7 - 3.6V 20MHz -40 - +85°C 10 years at 85°C SOP-8MB85RS16 Mar. 2012 16kbit 2.7 - 3.6V 20MHz -40 - +85°C 10 years at 85°C SOP-8

Serial interface (SPI)

Part Number Availabilty Size Operating Operating Operating Data PackageVoltage Frequency (Max) Temperature Retention

MB85RC128 Available 128kbit 2.7 - 3.6V 400kHz -40 - +85°C 10 years at 85°C SOP-8MB85RC64 Available 64kbit 2.7 - 3.6V 400kHz -40 - +85°C 10 years at 85°C SOP-8MB85RC64V Available 64kbit 3.0 - 5.5V 400kHz -40 - +85°C 10 years at 85°C SOP-8MB85RC16 Available 16kbit 2.7 - 3.6V 400kHz/1MHz -40 - +85°C 10 years at 85°C SOP-8MB85RC16V Available 16kbit 3.0 - 5.5V 400kHz -40 - +85°C 10 years at 85°C SOP-8

Serial interface (I2C)

FRAM E2PROM Flash SRAMType Non-volatile Non-volatile Non-volatile VolatileMethod writing Overwriting Erase (byte) + write Erase (sector) + write OverwritingWrite cycle time 150ns 3ms 1s 55nsEndurance 1 trillion 1 million 1 million Unlimited

Comparison of FRAM with other memory devices

Product overview

28-pin SOP-28 package 28-pin TSOP-28 package 48-pin TSOP-48 package

8-pin SOP-8 package

FRAM combines the benefits of Flash/E2PROMand SRAM / DRAM

Non-volatileVolatilepower required

Non-volatile

Slow blockaccess ROM

Fast unlimitedrandom R/W access

Fast unlimitedrandom R/W access

FlashE2PROM

SRAMDRAM

FujitsuFRAM