Gyroscope shock and disturbance detection circuit

摘要

The invention relates to integrated circuits, and more particularly, to systems, devices and methods of integrating a gyro sensing circuit with a gyroscope to detect a shock or a disturbance, and accurately differentiate rotation-based sense signals from noises introduced by the shock or disturbance. The gyro sensing circuit may be implemented in a differential or non-differential demodulation scheme, and comprises at least one demodulation unit and a peak detector. The at least one demodulation unit demodulates a gyro output signal provided by the gyroscope with a reference signal. In a demodulated gyro output signal, a shock signal or a gyro disturbance signal is substantially isolated out from interested gyro sense signals that are used to sense a rate of rotation. A peak detector samples the modulated gyro output signal, determines whether the signal exceeds a threshold level VTH and outputs a shock flag indicating a corresponding determination result.

主权项

1. A gyro sensing circuit based on a differential demodulation scheme, comprising:
a first demodulation unit, coupled to receive a gyro output signal from a gyroscope, the first demodulation unit demodulating the gyro output signal to a first demodulated gyro output using a first reference signal, the gyro output signal comprising a shock signal and a plurality of gyro sense signals that are related to an interested rate of rotation; a second demodulation unit, coupled to receive the gyro output signal, the second demodulation unit demodulating the gyro output signal to a second demodulated gyro output using a second reference signal, the first and second reference signals being symmetric with respect to a characteristic frequency of the gyroscope; a subtractor, coupled to the first and second demodulation units, the subtractor differentially combining the first and second demodulated gyro outputs to isolate the shock signal that is asymmetric with respect to the characteristic frequency; and a peak detector, coupled to the subtractor, the peak detector determining whether the combined gyro output exceeds a threshold level and generating a shock flag to alert a host whether an anomalous shock or disturbance situation occurs.