Dual-Mode Electric Power Sensing Based on MEMS Resonators

In this work, we present a novel dual-mode power sensing platform for real-time energy tracking based on a clamped-clamped microbeam resonator. The proposed device utilizes the Joule heating effect to transduce the input power to a rise in temperature in the structure, which also changes the elastic stiffness of the microbeam. This paper proposed two different readout methods for power sensing: static mode and dynamic mode. In the static mode, the beam is static without motion, the resistance of the beam was found to be linearly proportional to the input power with a responsivity of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$11.12\ \Omega/\text{mW}$</tex>. In the dynamic mode, the changes in the elasticity effects the dynamic vibration of the beam, the resonance frequency shift was found to be linearly proportional to the input power with a responsivity of 8650 Hz/mW. The increased flexibility of the dual-mode readout and the high sensitivity of the proposed approach is promising for monitoring power.