Angular velocity detection circuit, angular velocity detection apparatus, and failure determination system
View Patent ↗An angular velocity detection circuit is connected to a resonator for making excited vibration on the basis of a drive signal and detects an angular velocity. The angular velocity detection circuit includes: a self-vibration component extraction unit that receives, from the resonator, a detection signal including an angular velocity component based on a Coriolis force and a self-vibration component based on the excited vibration and extracts the self-vibration component from the detection signal; a direct-current conversion unit including an integration unit that integrates an output signal of the self-vibration component extraction unit; and a temperature characteristic compensation unit that compensates for a variation due to a temperature in an output signal of the direct-current conversion unit.
1. An angular velocity detection circuit that is connected to a resonator for making excited vibration on the basis of a drive signal and detects an angular velocity, the circuit comprising:
a self-vibration component extraction unit that receives, from the resonator, a detection signal including an angular velocity component based on a Coriolis force and a self-vibration component based on the excited vibration and extracts the self-vibration component from the detection signal;
a direct-current conversion unit including an integration unit that integrates an output signal of the self-vibration component extraction unit; and
a temperature characteristic compensation unit that compensates for a variation due to a temperature in an output signal of the direct-current conversion unit.
2. The angular velocity detection circuit according to claim 1 , wherein
the temperature characteristic compensation unit makes the compensation on the basis of a first-order term of a temperature characteristic of the output signal of the direct-current conversion unit.
3. The angular velocity detection circuit according to claim 2 , further comprising
a storage unit storing the first-order term of the temperature characteristic, wherein
the temperature characteristic compensation unit makes the compensation on the basis of the first-order term of the temperature characteristic stored in the storage unit.
4. The angular velocity detection circuit according to claim 1 , further comprising
an own failure determination unit that determines whether there is a failure in an angular velocity detection apparatus, on the basis of an output signal of the temperature characteristic compensation unit.
5. The angular velocity detection circuit according to claim 1 , wherein
the direct-current conversion unit includes an amplification unit that amplifies a signal, the amplification unit being provided before or after the integration unit.
6. The angular velocity detection circuit according to claim 1 , further comprising
an offset addition unit that adds an offset value to a signal, the offset addition unit being provided before or after the temperature characteristic compensation unit.
7. An angular velocity detection apparatus comprising:
a resonator, wherein the resonator makes excited vibration on the basis of a drive signal, obtains a Coriolis force caused by a rotation movement and the excited vibration, and outputs a detection signal including an angular velocity component based on the Coriolis force and a self-vibration component based on the excited vibration; and
an angular velocity detection circuit that is connected to the resonator and detects an angular velocity, the angular velocity detection circuit including:
a self-vibration component extraction unit that receives the detection signal and extracts the self-vibration component from the detection signal;
a direct-current conversion unit including an integration unit that integrates an output signal of the self-vibration component extraction unit; and
a temperature characteristic compensation unit that compensates for a variation due to a temperature in an output signal of the direct-current conversion unit.
8. A failure determination system, comprising:
the angular velocity detection apparatus according to claim 7 ; and
an external failure determination unit that receives an output signal of the temperature characteristic compensation unit to determine whether there is a failure in the angular velocity detection apparatus.