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

Claim 12:
13. A differential sensor system comprising:
a resonator;
a transducer configured to detect a first position of the resonator;
a second transducer configured to detect a second 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 second damping resistor configured to electrostatically actuate the second transducer and convert the thermomechanical noise of the resonator to a second 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;
a third switch configured to receive a third signal from the second transducer;
a second filter stage configured to receive the third signal and adjust a phase and a gain of the third signal and output a filtered third signal;
a fourth switch configured to receive a fourth signal from the second transducer;
a noise rejection stage configured to receive the filtered first signal, the second signal, the filtered third signal, and the fourth signal, and reduce a first differential value between the filtered first signal and the filtered third signal from a second differential value between the second signal and the fourth signal;
a first integrating capacitor coupled to the noise rejection stage;
a fifth switch configured to reset a charge on the first integrating capacitor;
a second integrating capacitor coupled to the noise rejection stage; and
a sixth switch configured to reset a charge on the second integrating capacitor,
wherein the first and third switches are controlled by a first phase signal,
wherein the second and fourth switches are controlled by a second phase signal,
wherein the fifth and sixth switches are controlled by a third phase signal, and
wherein the differential sensor system is time-multiplexed.