Magnetic Random Access Memory (MRAM) is a non-volatile computer memory technology, which has been in development since the 1990s. MRAM is loosely related to magnetic RAM matrices used in early computers (50's and 60's) in terms of addressing and function.

Unlike conventional RAM chip technologies, data is not stored as electric charge or current flows, but by magnetic storage elements.

The advantage of this technology is in the fact that the chips keep their stored data after switching the system off. Thus, computers and other devices can be built with with non-volatile memory, which is immediately ready for use after switching on. Additionally, MRAM requires far less memory refresh than capacitor-based DRAM and theoretically has speeds competitive with static RAM, the prime component in CPU cache.

MRAM normally functions by constructing minuscule magnetic fields at intersections in a grid of nanoscopic power rails. When current attempts to travel through a power rail which is opposing the polarization of one of the magnetic field bits, its current flow is mitigated and the bit value stored by the field is detected by this weakened current flow.

In the summer of 2003, a 128 kbit MRAM chip was introduced, which was manufactured with 0.18 micrometer technology. The core technology of MRAM is based on the magnetic tunnel effect.

Production in larger quantities of MRAM chips is expected in 2005, for usage in:

  • digital cameras
  • Notebooks
  • smart cards
  • mobile telephones.


An earlier version of this article was translated from the German-language Wikipedia.