A large number of computer users today keep their computers switched on day and night to avoid one problem: they do not want to go through the hassle of waiting for their computers to boot up. The problem has 2 parts: firstly, the booting up process eats up a time of between 4 to 5 minutes (Borin) {constituting ‘idle time’ for users} which is very valuable, and secondly, users have to endure seeing the same irritating operating system messages announcing ‘loading’ and ‘saving your settings.’ This problem that affects thousands of computer users is solved by MRAM {Magnetoresistive Random Access Memory} technology. An MRAM-empowered system does not require its user to keep the computer on 24 hours a day. In fact, it makes shutting down the computer between work sessions a more attractive option (Borin). This is because MRAM allows a user to just turn on the computer to have the last session immediately available; even shutting down the computer does not wipe out any data.
MRAM technology is able to achieve this great advantage to computer users because of its ‘ideal memory’ characteristic. At present, computers require to transfer data from the hard disk into local memory when the power is switched on, and that memory loading cannot even begin until after the hard drive has revved up to speed; when shut down is effected, data has to travel back in the reverse direction from the volatile memory to the hard drive. The MRAM solution is to permit data and programs to be retained in local memory (Borin). The MRAM technology unites a magnetic device with conventional silicon-based microelectronics to get the united qualities of non-volatility, ultra-fast operation speeds, and unlimited read-and-write endurance that is not provided by any other current computer memory technology (Genuth & Fresco-Cohen). MRAM utilizes spintronics whereby electron spin is employed to conserve information. Magnetic elements are employed to store data. It operates by building tiny magnetic fields at junctions in a network of nanoscopic power rails. When current tries to move through a power rail that is restricting the vibration of one of the magnetic field bits, its current flow is lessened and the bit value conserved by the field is identified by this lessened current flow.
MRAM technology is the latest in the field of computer memory. There are basically two types of computer memory – volatile and non-volatile. Volatile computer memory needs a continuous power supply to keep stored data, while non-volatile computer memory can keep stored data permanently without needing a continuous power supply. Most modern computers use volatile memory in the form of conventional RAM {random access memory} computer chips which use electrical charges to store memory bits (Tech-faq.com) and of course fully rely on the constant power supply; as a consequence of this, in the event of power being turned off, data is lost unless it was previously copied to the computer’s hard drive (Genuth et al.). This is because RAM capacitors leak their electrical charge (Tech-faq.com). ROM {read only memory} is a type of computer memory that is non-volatile because it conserves data that does not need regular rewriting; hence even if power is switched off, the data is retained. A modern version of ROM is Flash which, while retaining its feature of non-volatility, has the advantage over traditional ROM in that it is easily rewritable, thereby making it ideal for hard drives, thumb drives, and MP3 players. Flash however has 2 problems: it has a short lifespan and it has a significantly lesser write speed as compared to RAM. While MRAM technology is officially classified as a brand new kind of non-volatile computer memory, its uniqueness lies in its capability to have all the benefits of a normal non-volatile memory like ROM and Flash in addition to the speed of the faster volatile memory (Genuth et al.). The speed of MRAM is nearly 600% faster than conventional RAM. Furthermore, the various functions of MRAM technology are densely packed onto 1 chip that has the additional advantage of reduced product size and an impressive ultra cost-efficient memory solution (Borin).
Scientists began working on the MRAM technology as long ago as 1940. Pioneers in the work were Harvard physicists An Wang and Way-Dong Woo, as well as MIT scientist Jay Forrester (Genuth et al.). Scientists from IBM then came up with a series of important findings of the ‘giant magnetoresistive’ effect in thin-film frameworks in 1989 which resulted in IBM setting up a joint MRAM development program in collaboration with Infineon in 2000. Two years later NVE publicly declared Technology Exchange with Cypress Semiconductor culminating in the introduction of a 128 Kbit MRAM chip in 2003. In June 2004 Infineon introduced a 16 Mbit MRAM chip manufactured with 0.18-micron technology. In September the same year Freescale Semiconductor Products, which had been sampling MRAM, adopted it as a standard product.
The first commercial MRAM chip {with a 4 Mbit of memory} was sold in July 2006 by Freescale Semiconductor Products at a price of $ 25 each. By April 2008 Freescale which was a part of Motorola Semiconductor Products until 2004 had achieved sales in excess of 1 million chips (Mram-info.com/introduction). Several other competitors have also started working on the MRAM technology such as NEC, Toshiba, Samsung, Hynix, Siemens, Renesas, Grandis, TDK, Micromem, and Crocus. Some manufacturers are optimistic that in the future MRAM technology can be advanced to such an extent that users would need to just press the computer’s on/off button to shut off Windows, instead of going through the present rituals that comprise its shut-down process (Borin).
In November 2007, NEC Corporation declared that after continuous MRAM research spanning 7 years, it had created a new SRAM-compatible MRAM that can work at a speed of 250 MHZ thereby creating a new world record of MRAM operating speed {the normal MRAM operating speed is around half of this speed}. The special MRAM has a 1 megabit capacity and uses a memory cell containing 2 transistors, 1 magnetic tunnel intersection, and a unique circuit scheme.
Although MRAM is undoubtedly superior to all present types of computer memory, it is presently limited to 3 market sectors: Battery-Backed SRAM replacement, Data-Logging Specialty Memory, and Crucial Write Buffer Data for Higher Density {Lower Speed} Conservation. Its limited marketability is due to its current high price per MB ratio: its present price of $ 25 per 0.5 MB is very high as compared to the current selling prices of RAM {$ 25 per 256 MB} and Flash {$ 25 per 1 GB} (Genuth et al). Freescale, which currently has 45 customers, has plans to reduce its sale price (Mram-info.com/history) although there is no indication when or to what extent that will happen. Freescale and other manufacturers have to overcome the current high price per MB ratio if this high technology ‘new memory that doesn’t forget’ (Borin) can make serious inroads into the main lucrative market of computer memory chips.
References
Borin, Elliot. “New Memory That Doesn’t Forget.” 2003. Web.
Genuth, Iddo & Fresco-Cohen Lucille. “MRAM – The Birth of the Super Memory.” The Future of Things. 2006. Web.
“NEC Develops World’s Fastest SRAM-Compatible MRAM with Operation Speed of 250 MHZ.” 2007. Web.
“MRAM Introduction.” 2008. Web.
“MRAM History.” 2008. Web.
“What Is MRAM Magnetic Memory?” 2008. Web.