Digital phase tracking filter for position sensing

A position sensor device for measuring a position of a mechanical element, the position sensor device comprising:

• a plurality of position sensor elements adapted to generate a plurality of analog sense signals, each analog sense signal being a sinusoid function shifted over a different offset phase and having a same frequency, wherein an input phase of the sinusoid function is representative of the position to be measured,
• a digitization circuit that is coupled to the sensor elements and that is adapted to provide a digital signal representative of the input phase based on the plurality of analog sense signals, and
• a digital processing unit for outputting a device output signal indicative of the position to be measured based on a first output of the digital processing unit,
• wherein said digital processing unit comprises:
• an error signal generator for receiving the digital signal and a feedback signal and for computing an error signal indicative of a phase difference between the digital signal and the feedback signal,
• a digital filter comprising a common filter circuit for filtering the error signal to generate the first output,
• a feedback path for providing the feedback signal to the error signal generator, in which the feedback signal is based on the first output of the digital filter, and
• a filter selector to select a filter to be applied by the digital filter from a plurality of different filters, each having a different transfer function, wherein said selection is based on the error signal or an output of the digital filter,
• wherein said plurality of filters are implemented by the common filter circuit of the digital filter, and
• wherein the error signal or a signal derived therefrom on which the common filter circuit operates is scaled differently for each of the different filters to obtain different filter bandwidths depending on the selected filter.