Vibration rectification error correction circuit and sensor device

Abstract

To provide a vibration rectification error correction circuit that can reduce vibration rectification errors with simple calculations. [Solution] A vibration rectification error correction circuit including a signal processing unit that calculates the difference between a first signal value based on a physical quantity detected by a first sensor having a first detection axis and a second signal value based on the physical quantity detected by a second sensor having a second detection axis in the opposite direction to the first detection axis, wherein the vibration rectification error of the difference value is smaller than the vibration rectification error of the first signal value and smaller than the vibration rectification error of the second signal value.

Claims

1. The system includes a signal processing unit that calculates the difference between a first signal value based on a physical quantity detected by a first sensor having a first detection axis and a second signal value based on the same physical quantity detected by a second sensor having a second detection axis in the opposite direction to the first detection axis. A vibration rectification error correction circuit wherein the vibration rectification error of the difference value is smaller than the vibration rectification error of the first signal value and smaller than the vibration rectification error of the second signal value.

2. In claim 1, The vibration rectification error correction circuit is such that the second signal value is obtained by multiplying the signal value based on the physical quantity detected by the second sensor by a correction coefficient.

3. In claim 2, A vibration rectification error correction circuit, wherein the value of the correction coefficient is a value based on the ratio of the quadratic coefficient of the approximation formula for the output signal of the first sensor, with the physical quantity as a variable, and the quadratic coefficient of the approximation formula for the output signal of the second sensor, with the physical quantity as a variable.

4. In claim 1, The vibration rectification error correction circuit wherein the second signal value is the value obtained by dividing the signal value based on the physical quantity detected by the second sensor by a correction coefficient.

5. In claim 4, A vibration rectification error correction circuit, wherein the value of the correction coefficient is a value based on the ratio of the quadratic coefficient of the approximation formula for the output signal of the second sensor, which has the physical quantity as a variable, and the quadratic coefficient of the approximation formula for the output signal of the first sensor, which has the physical quantity as a variable.

6. In claim 1, The aforementioned physical quantity is acceleration, Each of the first sensor and the second sensor is, A cantilever that deforms when the aforementioned physical quantity is applied, A vibration rectification error correction circuit, comprising a quartz oscillator whose vibration frequency changes due to stress caused by the deformation of the cantilever.

7. A vibration rectification error correction circuit according to any one of claims 1 to 6, The first sensor and, A sensor device comprising the second sensor.

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