Design and applications of ferroelectric nonvolatile SRAM and flip-flop with unlimited read/program cycles and stable recall

Abstract

Circuit techniques to realize unlimited program cycle operation in ferroelectric nonvolatile (NV) SRAM have been developed with conventional ferroelectric materials. Program operation is separated into volatile write operation without polarization change and nonvolatile store operation with polarization change. Biasing of the memory cell is optimized to meet reliability requirements. The developed circuit principle is extended to implement a low-power nonvolatile flip-flop applicable to long communication range radio frequency identification tag LSIs.