12.1 An FPGA-Accelerated Fully Nonvolatile Microcontroller Unit for Sensor-Node Applications in 40nm CMOS/MTJ-Hybrid Technology Achieving 47.14μW Operation at 200MHz

Recently, the demand for low-power, high-performance microcontroller units (MCUs) for power-supply-critical sensor node applications has been increasing. In response to this demand, the use of nonvolatile memory elements for realizing MCUs for sensor node applications has been actively researched and developed. The latest nonvolatile MCUs (NV-MCUs) demonstrated 32b operation at 30MHz [1] and 8b operation at 100MHz [2]. However, this performance level is not suitable for sensor node applications that process large numbers of received signals and extract valuable information from them immediately to reduce the amount of transfer data to a data center. The use of various nonvolatile devices has also been proposed. However, these devices exhibit critical drawbacks when applied to sensor node applications, including limited endurance and low compatibility with standard CMOS. A spintronics-based nonvolatile device with unlimited endurance, a short switching time, and CMOS compatibility is a promising candidate for designing a low-power, high-performance NV-MCU.