DMA-driven control method for low power sensor node

Power reduction in sensor nodes is an essential technique for long-term operation. We noticed that central processing units (CPUs) accounted for a large volume of power consumption and that CPU functions were usually excessive for sensor node control. Direct memory access (DMA) was substituted for the CPU when iterative routine processing was operated in this research, and the CPU was made to fall asleep while the DMA responsibly controlled tasks. The experimental results revealed that DMA-driven control reduced power consumption to 37% compared with CPU-driven control in 28 MHz operation. We concurrently discovered defects in the existing micro-controller units (MCUs) for further reducing power. We also propose an improved hardware architecture.