A CMOS-MEMS Thermoresistive Micro Calorimetric Flow Sensor With Temperature Compensation

Abstract

In this paper, we propose a new 1D thermoresistive micro calorimetric flow (TMCF) sensor model for moist airflow with the temperature-dependent thermophysical properties. The 1D model and the corresponding proposed equivalent circuit model enable rapid design optimization of an ambient temperature-compensated TMCF (T2MCF) sensor integrated with the interface circuit by using a commercial 0.35- $\mu \text{m}$ 2P4M CMOS MEMS technology. The fabricated sensor shows a prominent sensitivity of 0.543 V/(m/s) and a low power consumption of less than 2.8 mW. Moreover, in comparison with the large drifting of 49% for the uncompensated TMCF sensor, the T2MCF sensor’s output has an ultralow drifting of 0.5% with the ambient temperature variation of 22°C~48°C. Therefore, this robust T2MCF sensor can be a promising Internet of Things (IoT) for smart energy-efficient buildings. [2018-0241]