High speed (10-20 ns) non-volatile MRAM with folded storage elements

In magnetoresistive random access memories (MRAMs), the read access time is a function of cell size (aspect ratio). Thus it is possible to design MRAMs for a wide range of access times. A prototype MRAM chip has been designed using 250 Omega folded memory cells, two-turn word lines, and a high-speed differential sensing scheme. Simulation results indicate the total delay through the analog circuitry to be limited to 9.8 ns, thus demonstrating the MRAM access time to be within the range 10-20 ns. Even though the power consumption of the drive circuitry tends to be high when active, the nonvolatile nature of MRAMs makes them ideal for low-power applications. >