A Novel Sensing Circuit for 2T-2MTJ MRAM Applicable to High Speed Synchronous Operation

We propose a novel sensing circuit for 2T-2MTJ MRAM that can be used for high speed synchronous operation. Proposed bit-line sense amplifier detects small voltage difference in bit-lines and develops it into rail-to-rail swing while maintaining small voltage difference on TMR cells. It is small enough to fit into each column that the whole data array on selected word line are activated as in DRAMs for high-speed read-out by changing column addresses only. We designed a 256Kb read-only MRAM in a logic technology to verify the new sensing scheme. Simulation result shows a 25ns RAS access time and a cycle time shorter than 10 ns.