Ultra-Low Power Microcontroller Architectures for the Internet of Things (IoT) devices

The term Internet of Things (IoT) refers to electronic devices and systems connected through the internet with additional computational competencies. The architectures targeting IoT applications consist of a sensing subsystem for data acquisition, low-power microcontrollers for digital processing, and a low-energy wireless communication subsystem. The current market trend is integrating these three subsystems into a fully-integrated single chip. The power consumption remains a dominant factor in wireless subsystems despite the fact that various techniques are being employed to minimize its effect. One novel way of reducing the overall power consumption in a wireless subsystem is to enhance the computational power and complexity of the processing subsystem. This approach can considerably reduce the transmitted data and overall power consumption in an IoT application scenario. In this regard, the accessibility of powerful, efficient, flexible and, most significantly, power-efficient digital processing architectures is necessary near the sensing subsystem. A thorough review of the state-of-the-art ultra-low-power digital processing architectures used for near sensor processing is carried out in the paper. Further, an exhaustive study of the low-power microcontrollers is also provided, emphasizing the main challenges and perceptions.