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MRAM - Magnetoresistive Random Access Memory
MRAM is a newly developed method of storing information that is still in its' infancy stages. While traditional RAM uses electrical charges to store information, MRAM uses magnetic charges to access stored data by aligning the polarity of the memory cells. By using magnetic charges rather than electric, the MRAM is able to store and access data at a much faster rate. The magnetic nature of MRAM also makes it a non-volatile memory, where RAM is a volatile memory. This means that When RAM loses electical current, it loses any information on it. MRAM, on the other hand, can retain the information stored on it after it loses power. Unfortunately, the high cost of MRAM has hindered its' development and production.

Description
In MRAM designs, Data is stored on thousand of tiny cells. Each of these cells is composed of two magnets. The poles of these magnets can be aligned to either parallel or anti-parallel configuration. In Most MRAM designs being studied, memory is read from the storage units by measuring the electrical resistance offered by the unit to determine whether the configuration is parallel or not. If the two magnets are parallel, then the storage unit is assigned a value of 1. If they are not parallel, then a value of 0 is given. From there, the same binary system that is common place in computers today would be used.
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However, there are several different types of writing techniques being considered at the moment. The simple technique that was the predominate technique in the first models of MRAM is placing each of the cells between two perpendicular write lines that would change the polarity of the cells when given current. However, this technique requires more power than newer methods. The newest and most practical method of writing is Spin-torque-technique. This method uses a similar structure of cells. However in this model, one magnet does not rotate. The other magnet is rotated by the introduction of spin stabilized electrons, whose torque switches the magnet. This technique requires far less energy, and is currently the cutting edge technique in MRAM technology.

Applications
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The applications of MRAM are extremely varied, ranging from use in everyday home computing devices, to mobile phones, to military computer systems. The benefit that it does not lose it's memory when it loses power means that it could transform the way people think of computers. There would no longer be boot up times for computers, as soon as the power supply was set up for all parts of the computer, then the computer could process the data currently on MRAM chip, bringing the computer up to exactly the same screen it was on before shut down.
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On top of this benefit, MRAM is much denser than standard RAM, which means much more memory can be put in much smaller spaces. MRAM is desirable and beneficial because it uses a non-volatile storage medium, like Flash, but is still comparable to today's fastest memory, the SRAM, which is used in CPU caches. Also, because RAM requires a constant electrical charge over any area holding data and MRAM does not, MRAM requires far less battery power. With the world of electronics constantly being made smaller, more portable, and more efficient, a technology that uses less battery and fits into smaller spaces than previous technology is extremely desirable.


Related Links
http://www.mram-info.com/
http://www.eetimes.com/showArticle.jhtml?articleID=218000269
http://www.eetimes.com/showArticle.jhtml;jsessionid=YLZEROMMDLZWNQE1GHPSKHWATMY32JVN?articleID=201801174
http://thefutureofthings.com/articles/36/mram-the-birth-of-the-super-memory.html
http://searchstorage.techtarget.com/sDefinition/0,,sid5_gci539346,00.html