Serial magnetoresistive random-access memory (MRAM) may find wide-scale use in the emerging smart meter market. Everspin Technologies Inc. (USA), a spinoff of Freescale Semiconductor Inc., says its new serial peripheral interface also could make its MRAMs popular for data logging in industrial control, automotive and printer applications. The new serial devices aim to extend the penetration of MRAM reach into low-cost consumer devices and industrial controllers.
MRAM does not store data as a charge, but instead in the magnetic polarization of a ferromagnetic plate. Two plates are separated by an insulating layer, with the bottom plate pinned to a particular magnetic polarity while the upper plate has a programmable polarity. If the two layers match, a ‘0’ is stored, and if they have opposite polarities, a ‘1’ is stored. A memory cell is read out by detecting its resistance.
Everspin's new serial MRAM family is available in 256 Kbit, 512 Kbit and 1 Mbit capacities, and a 4-Mbit version is due out next year. Flash memory devices have capacities around 1,000 larger, but MRAM is aimed at critical applications that do not require high memory density but do need ultra-high reliability. MRAM memory cells do not require write delay times, run at clock speeds up to 40 MHz, and are estimated to retain data without power for up to 20 years.
Other memory technologies, such as flash, EEPROM and FRAM, also provide non-volatile storage, but Everspin says that MRAM offers higher security due to its simpler programming method, which works like fast SRAM. According to Everspin, other memory technologies require extra steps to insure that data is not lost if power is interrupted during a read/write cycle.
MRAMs are already being used for critical program and data storage in extreme environments. Everspin recently won a contract from Airbus to supply 4-Mbit and 16-Mbit MRAMs for the flight control computer of the next-generation Airbus A350.
Informative articles
Password forgotten?
)
