MRAM - Newer Type of RAM - MRAM - Introduction to Magnetoresitive RAM

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Newer Type of RAM - MRAM

The advancement in the technology has continued. Some noteworthy German engineers and physicists have developed a prototype of an advanced hi-fi RAM system whose processing speed theoretically nears that of the computing process. It is evident from the report in an article in NewScientist Tech Blog (which is now merged with Short Sharp Science) that the technology being proposed the fastest of all the RAM technology that currently available. It is being speculated that the introduction of MRAM will cause an awesome change in the mobile market due to the low cost and the higher capabilities shown by MRAM. However, MRAM is only in its experimental stages now, and is not available for the distribution.

From the name one can judge that MRAM uses magnets to store the signal. In the conventional standard RAM the storage of 0 or 1 happens as the level of charge in the capacitor. On the contrary the MRAM stores a 0 or 1 as the polarity of direction in the small magnet. The small magnets can be flipped if situated next to a larger fixed magnet. The data can be recovered by passing the current through the magnet pair in order to read the direction of the magnetic field created as the result of passage of current.

Another variant of the MRAM prototype which uses electron spins to flip the field was proposed by two scientists from Physical technical Federal Lab in Germany. Namely, Santiago Serrano-Guisan and Hans Schumacher collaborated with the university of Bielefeld and Singulus Nano- Deposition Technologies and created a well defined “spin-torque” system. The creators have claimed that this spin torque technology is faster than any other RAM technologies proposed. The speed of the MRAM system depends on how fast the magnetic field is flipped. The drawback of this system is that when the polarity of the magnet gets changed the magnets may take additional flips to restore to an equilibrium position. This certainly reduces speed and increases the time. But the researchers have developed ways to eliminate the extra “wobbling” effect. Calculations by the researchers show that this spin torque has reached the theoretical speed of the MRAM.

One researcher has shown with some of his calculated results that the earlier version of the theoretical MRAM device is curtailed at 10 nanosecond pulses. He has also shown that the later technology prototype that implements spin torque effect is ten times faster than its predecessor. The researchers have also proven that some of the conventional RAM requires up to 30 nanoseconds to perform the same operation as that of the newer prototype MRAM.

The major hurdle which lies in the path of implementation of the MRAM is the current level that is being used for the tested devices. It has been detected that the current levels used to activate the tested devices are too high to implement the MRAM circuitry. Researches are trying to develop the circuits so that the MRAM is suitable to be used for all the compatible devices. They have to advance their technology to reduce the current levels compatible with the CMOS transistors.