High-Sensitivity Transimpedance Amplifier for MEMS Microsensor Readout in Acetone Vapor Detection

The microelectromechanical systems (MEMS) technology has been successful in yielding high-performance sensors for the measurement of pressure, vibration, inclination, and position. It is making progressive inroads in the gas sensing field for healthcare monitoring systems. This technology yields miniaturized sensors with reduced power consumption, faster response times, and lower unit costs in high volumes. This paper presents a brief introduction to exhaled breath acetone sensors based on MEMS and a study of a low-current front-end circuit for healthcare systems implementation for the detection of acetone vapor. The proposed capacitive sensor includes a high-sensitivity current-to-voltage converter, also known as a transimpedance circuit (TIA) is suggested. The advantage of t-network topology is that high gain and high sensitivity (1 V/1 nA) can be obtained by using kilo-range resistors, which are appropriate for on-chip circuitry. The obtained results offer a non-invasive alternative way the diagnosis of diabetic patients through exhaled breath analysis.