The control-system structure and behaviour are considered for annanalogue and a digital servo-accelerometer having a dynamic range fromnmg to several g (1g=9.81 ms-2), for use in low-frequencynapplications. The paper emphasises the derivation of mathematicalnmodels, which are presented together with simulated and test resultsnobtained from the implementation of these strategies on anbulk-micromachined silicon sensing element employing capacitive signalnpick-off. The digital device, which is based upon oversamplingnconversion, proved to have superior stability compared to the analoguenaccelerometer. Furthermore, it has the advantages of producing a directndigital output signal and an inherent self-test feature
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