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04 September, 2018
Fujitsu Semiconductor Limited

Fujitsu has launched a new 4Mbit Serial FRAM with upper compatibility to EEPROM

Optimal non-volatile memory for real-time data logging such as 3D positioning data of event data recorder

Yokohama, Japan, September 4, 2018 – Fujitsu Semiconductor Limited today announced that it has developed the MB85RS4MT, a 4Mbit FRAM that has the highest density in Fujitsu's serial interface family of FRAM non-volatile memories. Mass-produced products are currently available.

In a changing environment, with increasing volume of sensor information data and expanding edge-computing, there are a number of requests from the customers that they prefer increased read/write cycles, shortened data writing times, and increased memory density.This new product is a solution to meet the requirements of customers who are not satisfied with existing EEPROMs.

The MB85RS4MT is optimal for various applications requiring real-time or frequent data logging, such as driving/navigation recorders, industrial robots, computer numerical control (CNC) machine tools, measurement equipment, smart meters, and consumer equipment.

Today Fujitsu Semiconductor launches a new 4Mbit FRAM product, the MB85RS4MT, that has the highest density in our FRAM lineup of serial peripheral interface (SPI) products. For around 20 years, Fujitsu Semiconductor has mass-produced FRAM non-volatile memory products featuring high read/write endurance, high-speed write operation, and low power consumption.

MB85RS4MT SOP Package
MB85RS4MT SOP Package

Applications suited for MB85RS4MT
Applications suited for MB85RS4MT

This FRAM product features a guaranteed 10 trillion read/write cycles, which is about 10 million times of that competitive non-volatile memory, EEPROM.
Therefore, the guaranteed read/write cycle limit does not become a bottleneck in customer product design, even if the MB85RS4MT is used for memory for frequent data logging of sensor information in edge-computing. (Fig.1)

Fig.1:Read/Write Cycles Comparison
Fig.1: Read/Write Cycles Comparison

The FRAM product also features high-speed write operation by writing data with an overwrite sequence with no erase operation. While conventional non-volatile memories like EEPROM and flash memory require additional time for the erase operation in addition to normal write operation.
This fast write operation helps to protect data against sudden voltage drops such as power outages during writing. (Fig.2)

Fig.2:Write Time Comparison

Fig.2: Write Time Comparison (at voltage drop)

Since the MB85RS4MT operates within a wide power supply voltage range, from 1.8V to 3.6V, it can be used in customer end-products with other peripheral electronics components operating at either 1.8V or 3.6V. Its operating currents are very small, with a maximum operating current of 250μA at 1MHz operation and a maximum standby current of 50μA. This means, this FRAM product has the advantage of low power consumption, due to its low operating voltage and low operating current.

The FRAM product is in an industry-standard 8-pin SOP package, making it easy to replace existing EEPROM in 8-pin SOP. This enables customers to switch to FRAM products without requiring major design changes to motherboards in end-products.

Fujitsu Semiconductor announced new FRAM products operating at −55°C in April and new 8Mbit parallel FRAM products in June. This time it has developed new 4Mbit serial FRAM products with SPI interface. Fujitsu continues to develop memory products that are optimized for various applications in order to solve customer problems.

Key Specifications

  • Part Number: MB85RS4MT
  • Density (configuration): 4Mbit (512K × 8bit)
  • Interface: SPI (Serial Peripheral Interface)
  • Operating frequency: Maximum 40MHz
  • Operating voltage: 1.8V to 3.6V
  • Operating temperature range: -40°C to +85°C
  • Read/Write endurance: 10 trillion times (1013 times)
  • Package: 8-pin SOP

Glossary and Notes

Ferroelectric random-access memory. A type of memory that uses a ferroelectric file as capacitors that store data. Retains contents even when power is removed. Combines benefits of both ROM and RAM, with fast write speed, low-power consumption, and high read/write cycle endurance. Also known as FeRAM. Produced by Fujitsu Semiconductor since 1999.

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About Fujitsu Semiconductor
Fujitsu Semiconductor Group includes a system memory group that is focused on high quality, high performance Ferroelectric random access memory (FRAM), wafer foundry group that has excellent technology and support, and the sales business of Fujitsu Electronics and overseas sales companies. Headquartered in Yokohama, we established as a subsidiary of Fujitsu Limited on March 21, 2008. Through its global sales and development network, with sites in Japan and throughout Asia, Europe, and the Americas, we offer semiconductor solutions to the global marketplace.
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