Feasibility study of AC bridges in MEMS pressure sensors

A study on the feasibility of using AC bridges in MEMS (Micro Electro Mechanical Systems) sensors is carried out in this project. Normally DC bridges are used in MEMS sensors to sense the output. AC measurements have some advantages over DC measurements like improved resolution, accuracy and aging information. In this work, a pressure sensor with 150kPa full scale span (FSS) is considered for studies. Schering bridge is used in this pressure sensor to sense the output. The main advantage of using Schering bridge is that aging information can be found out by calculating the dissipation factor. Sensitivity of the sensor is estimated as 9.3 × 10^-3 mV/V/kPa.