Authors: A. Tételin, H. Lévi, B. Mongellaz and C. Pellet
Affilation: Laboratoire IXL, France
Pages: 146 - 149
Keywords: humidity sensor, capacitive sensor, VHDL-AMS modeling, analog behavioral models
Measuring relative humidity in breath is useful for diagnosing pulmonary diseases. Humidity capacitive sensors were developed to equip a portable clinical device. Simulation is needed to design an electronic interface circuit to be integrated on the same chip as the sensors. A behavioral model of one of these sensors is set out in this paper. It is designed to be included in the model of the microsystem-to-be. It is based on experimental results on the static and dynamic responses of the sensor to humidity and temperature changes. Simulation results fit experimental data with an error inferior to 1%. The model is an illustration of VHDL-AMS capabilities as a modeling language to describe physical phenomena. The method of modeling can be extended to other kinds of sensors. Including the model in a simple microsystem model provides encouraging results.