Ultra-low-energy near-threshold biomedical signal processor for versatile wireless health monitoring

In this paper, an ultra-low-energy biomedical signal processor (BSP) is proposed for wireless multi-channel physiological signal monitoring. This BSP integrates a RISC core and application-specific hardware accelerators (ASHAs) to achieve ultra low power consumption while meeting required performance. Various low power design techniques from system to circuit levels are applied, including event-driven signal processing, dynamic clock management, near-threshold operation, glitch-free clock generation, fine-grain clock gating, and ultra-low-voltage level shifting. The BSP can operate with supply from 1.8V down to 0.5V. With integrated ECG ASHAs based on the discrete wavelet transform, its overall energy consumption is 20.4pJ/cycle at 0.5V and 10MHz when performing a real-time wireless ECG monitoring.