Design and application of ferroelectric memory based nonvolatile SRAM

Circuit techniques to realize stable recall operation and virtually unlimited read/program cycle operations in ferroelectric memcry based nonvolatile (NV) SRAM composed of six-transistor and fourferroelectric capacitor cells have been developed. Unlimited program cycle operation independent of ferroelectric material characteristics is realized by proper control of plate lines. Reliability evaluation results show that the developed memory cell has sufficient operation margin after stresses of temperature, fatigue, DC bias. Application of NV-SRAM to programmable logic devices has been discussed with a prototype of dynamically programmable gate arrays.