Self-powered signal processing using vibration-based power generation

TLDR

Low‑power design trends suggest that ambient energy could power future digital systems. The system uses a moving‑coil electromagnetic transducer to harvest vibration energy, with an ultra‑low‑power controller and subband‑filter DSP load integrated in a 0.8 µm CMOS chip. Experiments demonstrate that the chip can self‑power a 500 kHz subband‑filter DSP, consuming only 18 µW, with a single vibration pulse enabling 23 ms of operation (≈11,700 cycles) and generating about 400 µW of power.

Abstract

Low power design trends raise the possibility of using ambient energy to power future digital systems. A chip has been designed and tested to demonstrate the feasibility of operating a digital system from power generated by vibrations in its environment. A moving coil electromagnetic transducer was used as a power generator. Calculations show that power on the order of 400 /spl mu/W can be generated. The test chip integrates an ultra-low power controller to regulate the generator voltage using delay feedback techniques, and a low power subband filter DSP load circuit. Tests verify 500 kHz self-powered operation of the subband filter, a level of performance suitable for sensor applications. The entire system, including the DSP load, consumes 18 /spl mu/W of power. The chip is implemented in a standard 0.8 /spl mu/m CMOS process. A single generator excitation produced 23 ms of valid DSP operation at a 500 kHz clock frequency, corresponding to 11,700 cycles.