2Mb SPRAM Design: Bi-Directional Current WriteandParallelizing-Di rection Current ReadSchemesBasedon Spin-Transfer TorqueSwitching

A 1.8V 2-Mb SPRAM (SPin-transfer torque RAM) chip using 0.2-mu m logic process with MgO tunneling barrier cell demonstrates the circuit technologies for potential low power non-volatile RAM, or universal memory This chip features: an array scheme with bit-by-bit bi-directional current write to achieve proper spin-transfer torque writing of 100-ns, and parallelizing-direction current reading with low voltage bit-line that leads to 40-ns access time.