A 28nm 10Mb Embedded Flash Memory for IoT Product with Ultra-Low Power Near-1V Supply Voltage and High Temperature for Grade 1 Operation

In this paper, we present an Embedded Flash Memory (eFlash) based on logic-28nm process for Internet of Things (IoT) product. IoT product requires high performance, low power operation and immune to the high temperature. Based on a power-efficient 28nm process technology, we implemented the ultra-deep sleep mode (<1uA). Through the WL Boosting and Adaptive Control Sensing Scheme (WBACS), we achieved fast read speed (3.2Gbit/s) and robust sensing margin. High voltages can be generated stably in ultra-low power IO 1.1V by using Double-Boost-Clock (DBC). Through the technique that positive/negative Bi-Directional Charge Pump (BDCP), three high voltages required for Program/Erase operation can be generated from two charge pumps. As a result, we have developed an area competitive eFlash IP (Size 1.27 mm2). Based on these technologies, it was confirmed that 28nm-eFlash operates at ultra-low power (Core-VDD 0.85V & IO 1.1V) and high temperature (Tj 150°C) successfully. And these technologies were mounted in the world's first 28nm process MCU-Connectivity One Chip Solution.