Magnetic Ram......The future RAM

Magnetoresistive Random Access Memory (MRAM) combines a magnetic device with standard silicon-based microelectronics to obtain the combined attributes of non-volatility, high-speed operation and unlimited read and write endurance not found in any other existing memory technology. We describe how the cell architecture, bit structure, and the toggle switching mode are combined to provide significantly improved operational performance and manufacturability as compared to MRAM based on conventional switching. One potential barrier to MRAM manufacturability is associated with the method of write selection in which two orthogonal currents in coincidence must write data, whereas each of the orthogonal currents alone cannot disturb the data. This "2D" selection method places constraints on uniformity of MRAM memory cells. Using a transistor per cell for write select greatly improves operating margins and lowers write currents.