An Information-Aware Adaptive Data Acquisition System using Level-Crossing ADC with Signal-Dependent Full Scale and Adaptive Resolution for IoT Applications

This paper proposes an information-aware (IA) adaptive data acquisition (ADA) system for the Internet of Things (IoT) applications. The system can obtain valid information adaptively thanks to 1) signal-dependent full-scale feature tracks the amplitude-domain activity of the event; 2) level-crossing (LC) ADC with slope detector delivers the time-domain activity; 3) the IA algorithm determines the quantization resolution according to the detected signal activities. The proposed clock-free event-driven ADA system can reject the redundant data, and compress the valid data from the source, thus saving its power and the power of subsequent data-processing systems. The long-term average power consumption of the system is 128 nW, the resolution varies from 3 to 7 bits according to the input signal state. Compared with conventional ADCs, LC-ADC can compress the data by 2.5x [1]. Further, the proposed system has 15x higher compression ratio (CR) than that of LC-ADC.