Multi-bit nonvolatile flip-flop based on NAND-like spin transfer torque MRAM

Nonvolatile flip-flops (NVFFs) integrating emerging spintronics devices such as magnetic tunnel junction (MTJ) are under intensive investigation. They allow computing systems to be powered-off during the standby state, hence high static power issue of conventional CMOS technology can be addressed. MTJ based on spin transfer torque (STT) effect provide non-volatility, good endurance and 3D integration with CMOS based circuits. However, it suffers from relative long switching delay, high switching power and asymmetric switching issues. In this work, we first present a multi-bit NVFF using NAND-like spintronics (NANS-SPIN) devices which are written by STT and spin orbit torque (SOT) currents. It shows advantages in terms of power consumption, area overhead and write voltage. Then, functionality and performance of the proposed NVFF will be simulated and validated.