Robust inertial sensor self-test

An inertial sensor with self-test capability, comprising:

• a signal generator that generates a non-periodic self-test signal pattern;
• one or more self-test drive electrodes that receive the non-periodic self-test signal pattern;
• a proof mass that is driven by the one or more self-test drive electrodes in accordance with the non-periodic self-test signal pattern;
• one or more sense electrodes that sense movement of the proof mass;
• sense circuitry coupled to the proof mass, wherein the sense circuitry is configured to generate a sense signal based on the sensed movement of the proof mass detected by the one or more sense electrodes;
• and
• processing circuitry configured to correlate the sense signal with the non-periodic self-test signal pattern and identify an error based on the correlation.

A method for performing a self-test of an inertial sensor, comprising:

• generating, by processing circuitry of the inertial sensor, a non-periodic self-test signal pattern;
• driving a proof mass of the inertial sensor in accordance with the non-periodic self-test signal pattern;
• sensing, by one or more sense electrodes of the inertial sensor, the movement of the proof mass while the proof mass is driven by the one or more self-test drive electrodes;
• generating, by the processing circuitry of the inertial sensor, a sense signal based on the sensed movement of the proof mass, wherein the sensed movement is based on the driving of the proof mass and an environmental vibration;
• correlating, by the processing circuitry, the sense signal with the non-periodic self-test signal pattern, wherein an environmental vibration portion of the signal is not correlated with the non-periodic self-test signal pattern and a driven portion of the sense signal is correlated with the non-periodic self-test signal pattern;
• and
• identifying, by the processing circuitry, an error based on the correlating.