Abstract: A magnetostrictive stress and torque sensor using the component of the output signal in-phase with the drive voltage to monitor stress or torque. In some embodiments, it may use the quadrature or out-of-phase component, or some combination of the in-phase and out-of-phase components. Such phase component monitoring has several advantages over magnitude detection, including a response which is a more linear function of torque, and which is not subject to overmodulation problems.

Abstract: A system for determining the occurrence of a misfire in an internal combustion engine includes an oscillator, a phase detector coupled to receive an engine timing signal and the oscillating signal from the oscillator for producing an error signal functionally relating to phase difference between the signals. A loop filter is coupled to the phase detector for producing a tracking signal for producing the oscillating signal functionally related to the tracking signal. A phase error accumulator is coupled to receive the error signal and is operative to produce an output signal when the magnitude of at least one of the duration and magnitude of the error signal exceeds a predetermined value.