System-Level Optimization of MEMS Thermal Wind Sensor Based on the Co-Simulation of Macromodel and Board-Level Interface Circuits

The low efficiency of iterative optimization in Microelectromechanical Systems (MEMS) devices is due to their complete separation from interface circuits. In the case of board-level circuits, this problem is particularly evident. To solve this problem, this paper proposes a system-level co-simulation strategy that combines the macromodel of a MEMS device extracted by Verilog-A with board-level circuits, exploring an efficient and accurate MEMS-assisted optimization design method. In order to better adapt to actual interface circuit, the macromodel of sensor is divided into two sub macromodels corresponding to the control circuit and processing circuit. The sub macromodels are coupled with the temperature information. Subsequently, the influence of packaging is investigated based on co-simulation approach. The simulation results show the power consumption is proportional to the heat conductivity of packaging, and the sensitivity is inversely proportional to heat conductivity. Therefore, based on system-level co-simulation prediction, a hollow glass with low heat conductivity is used to encapsulate the sensor chip. The comparison shows good agreement among the results of co-simulation, experiment and finite element analysis. Specifically, the heating power of the latest sensor ranges from 70 mW ~ 150 mW, and the sensitivity has been improved to 16.3 mV/(
$\text{m}\cdot \text{s}$
-1). Therefore, this robust system-level co-simulation method has shown its potential in MEMS design and optimization. [2023-0068]