Novel Multi-Bit Non-Volatile SRAM Cells for Runtime Reconfigurable Computing

We discuss non-volatile SRAM cells capable of storing multiple bits and their applications as multi-context configuration memory. The cells are based on the standard 6T SRAM with multiple pairs of programmable resistors such as magnetic tunnel junction or resistive memory elements. In one of the cell designs the active state of the SRAM can be switched in one clock cycle by the use of an additional equalizer transistor, without the need to turn off the power to the cell, allowing real-time and low energy switching between different contexts in reconfigurable circuits. Other variations of the multistate non-volatile SRAM cells are also discussed.