Parametric amplification in MEMs devices

Abstract

Parametric amplification in a low capacitance MEMS parallel-plate device is demonstrated and is shown to still follow theoretical approximations. The general power gain of such a system is shown to be dependent on load and capacitance change, i??n. A means of estimating characterization of capacitance change of the device at resonance (i??n) through the extraction from current parameters is proposed. i??n values ranging from 0.001 to 0.008 are obtained. A new resonance detection scheme is proposed, which removes the necessity for a DC-bias to the device. The resonance characteristics of this 3f-detection scheme are analysed and demonstrated. This scheme allows the detection of resonance for one-port devices with high parasitic capacitance. Previous known methods were limited to two-port devices.An Electrical Equivalent Modelling scheme is also proposed, based on Bond Graph modelling. It allows the representation of mechanical systems in electrical domain and extract mechanical parameters from electrical signals.