Self-Sustained Resonant Accelerometer Based on Thermal-Actuation and Piezoresistive-Detection Mechanis

This paper presents the first self-sustained resonant accelerometer based on thermal-actuation and piezoresistive-detection resonators (TPR). A selfsustaining oscillation loop is physically established when the thermal energy from the bias current through the nanobeam compensates for vibration energy losses in the Double-ended tuning fork (DETF) resonators, eliminating the necessity of complex closed-loop control circuits. Experimental results demonstrate self-oscillation with a DC input current of$390 \mu \mathrm{A}$. A sensitivity of$428 \text{Hz} / \mathrm{g}$, and a bias instability of$36 \mu \mathrm{g}$can be observed under the thermal-piezoresistive self-oscillation cases. This study opens up a new way for realizing resonant accelerometers with exceedingly simple control circuitry, low power consumption and comparable resolution.