15.8 A 22nm 10.8Mb Embedded STT-MRAM Macro Achieving over 200MHz Random-Read Access and a 10.4MB/s Write Throughput with an In-Field Programmable 0.3Mb MTJ-OTP for High-End MCUs

As the range of applications for industrial and ioT devices expands, such as with the integration of Al, higher-speed information processing will be desired for endpoint devices to reduce network latency and power consumption, due to network communication with the cloud. For sophisticated control and real-time processing, high-processing performance with GHz-class CPU clock frequencies and robust security is required in the crossover area located on the performance boundary between high-end microcontroller units (MCUs) and low-end microprocessor units (MPUs) [1]. One possible solution for such MCUs is to apply DVFS, which dynamically controls the supply voltage and the clock frequency depending on the processing load. In terms of process scaling, finer logic processes, 22 nm and beyond are being applied, but the development and manufacturing of embedded flash memories (eFlash) become more difficult and expensive [1]. For this reason, various types of emerging memories have been developed, and an embedded STT-MRAM (eMRAM) has begun to be used for mass production, since eMRAM has advantages such as high reliability and fast write speed compared to other emerging memories.