Patent ID: 11885647
Assignee: ROHM CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A sensor apparatus comprising:
a resonator;
a transducer configured to detect a position of the resonator;
a damping resistor configured to electrostatically actuate the transducer and convert a thermomechanical noise of the resonator to an electromechanical noise;
a first switch configured to receive a first signal from the transducer;
a filter stage configured to receive the first signal and adjust a phase and a gain of the first signal and output a filtered first signal;
a second switch configured to receive a second signal from the transducer; and
a noise rejection stage configured to receive the filtered first signal and the second signal and reduce the filtered first signal from an output signal of the noise rejection stage,
wherein the first switch is controlled by a first phase signal and is configured to open or close an electrical pathway between the transducer and the damping resistor,
wherein the second switch is controlled by a second phase signal and is configured to open or close an electrical pathway between the transducer and the noise rejection stage, and
wherein, in a first configuration, the first switch is open and the second switch is closed, and a pulse input voltage to the resonator produces a current correlated to the electromechanical noise.