%0 Conference Paper %B TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th Innational Conference on, 8-12 June 2003, Boston, USA %D 2003 %T Electro-mechanical feedback for realization of a mechanical spectrum analyzer %A Cretu, E %A Rocha, L A %A Wolffenbuttel, R F %C Boston, MA, USA %K capacitors microactuators spectral analysers MEMS actuation capacitors driving electrical frequency electrically controlled signal electro-mechanical feedback functional coupling harmonic common mode voltage intrinsic nonlinear coupling microdomain monito %P 1407 - 1410 %U http://ieeexplore.ieee.org/search/srchabstract.jsp?arnumber=1217038&isnumber=27359&punumber=8626&k2dockey=1217038 %X An important feature of MEMS, still underutilized, is the tight coupling between the electrical and mechanical quantities in the micro domain. This paper demonstrates the benefits of such a functional coupling for a specific device: a real-time mechanical spectrum analyzer. A surface micromachined accelerometer was designed, with a voltage-controlled gain. By applying an harmonic common-mode voltage on the actuation capacitors, the intrinsic nonlinear coupling performs a correlation between the input acceleration and an electrically-controlled signal. To reduce the distortion, a differential, twin-accelerometer scheme is used. Time-multiplexed signal processing gives both the real and the imaginary components of the selected spectral line. A mechanical spectrum analyzer for low-frequency domains is obtained when the driving electrical frequency is swept over the range of interest. The operating principle has been confirmed by measurements, and is expected to yield new opportunities in the field of low-power, low-cost condition monitoring equipment. %Z E.Cretu, L.A. Rocha, R.F. Wolffenbuttel [2003] -_Electro-mechanical Feedback for Realization of a Mechanical Spectrum Analyzer_, in Transducers_03, The 12th International Conf. on Solid-State Sensors, Actuators and Microsystems, Boston, Ma, USA, June 8-12, pp1407-1410 %8 June 8-12 %9 inproceedings