JP2014197010A - Angular velocity detector and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an angular velocity detector and an electronic device capable of compensating for the temperature fluctuation of an angular velocity signal caused by a vibration leakage component without using a high-order temperature compensation circuit.SOLUTION: An angular velocity detector 1 includes: a vibrator (gyrosensor element 100) for generating a signal including an angular velocity component and a vibration leakage component; a driving circuit 20 for generating a driving signal to supply it to the vibrator; an angular velocity signal generation section (synchronous detection circuit 350 and integration circuit 360) for extracting the angular velocity component from the signal generated by the vibrator and generating an angular velocity signal 36a according to the size of the angular velocity signal; a vibration leakage signal generation section (synchronous detection circuit 352 and integration circuit 362) for extracting the vibration leakage component from the signal generated by the vibrator and generating a vibration leakage signal 36b according to the size of the vibration leakage component; and an addition/subtraction section (addition/substraction circuit 370) for adding or subtracting the vibration leakage signal 36b to or from the angular velocity signal 36a so as to correct the temperature characteristics of the angular velocity signal 36a.

Description

  The present invention relates to an angular velocity detection device and an electronic apparatus.

  Currently, various electronic devices and systems that are equipped with an angular velocity detection device and perform predetermined control based on the detected angular velocity are widely used. For example, in a travel control system for an automobile, processing for preventing a side slip of the automobile or detecting a rollover is performed based on the detected angular velocity.

  In these electronic devices and systems, if the angular velocity detection device breaks down, incorrect control is performed, so if a failure occurs, countermeasures such as turning on a warning lamp are taken, and failure diagnosis of the angular velocity detection device is performed. Various techniques for doing so have been proposed. For example, in Patent Document 1, paying attention to the fact that the output signal from the vibrator of the angular velocity detection device includes a self-vibration component (vibration leakage component) based on the excitation vibration of the vibrator along with the angular velocity component. A technique for determining the presence or absence of a failure by extracting a vibration leakage component from an output signal and monitoring its amplitude is disclosed. Japanese Patent Application Laid-Open No. 2004-228561 proposes a technique for performing fault diagnosis by reliably generating a self-vibration component by performing balance tuning so that the vibration energy of the vibrator becomes unbalanced.

JP 2000-171257 A JP 2010-107416 A

  By the way, it is ideal that the vibration leakage component is not extracted at all in the angular velocity component extraction circuit. However, in practice, the phase shift of the synchronous detection clock occurs due to variations in circuit manufacturing, and the extracted angular velocity signal (gyro The vibration leakage component enters the signal. Therefore, in particular, when the vibration leakage component is intentionally increased as in Patent Document 2, there is a problem that the temperature characteristic of the angular velocity signal is deteriorated due to the influence of the temperature characteristic of the vibration leakage component. If the temperature characteristic of the vibration leakage component is a linear function or a quadratic function, it can be corrected by a small-scale temperature compensation circuit, but actually shows a temperature characteristic expressed by a high-order function, If the temperature is corrected by a higher-order function circuit, the circuit scale becomes large.

  The present invention has been made in view of the above problems, and according to some aspects of the present invention, a high-order temperature compensation circuit is used to detect temperature fluctuations in the angular velocity signal due to vibration leakage components. Therefore, it is possible to provide an angular velocity detection device and an electronic apparatus that can compensate for each other.

(1) In the present invention, a vibrator that generates a signal including an angular velocity component according to the magnitude of the angular velocity and a vibration leakage component of vibration based on the drive signal, and the drive signal is generated and supplied to the vibrator A driving unit that extracts the angular velocity component from the signal generated by the vibrator, generates an angular velocity signal corresponding to the magnitude of the angular velocity component, and the vibration from the signal generated by the vibrator. A vibration leakage signal generation unit that extracts a leakage component and generates a vibration leakage signal according to the magnitude of the vibration leakage component, and the vibration leakage signal is added to the angular velocity signal so as to correct a temperature characteristic of the angular velocity signal. And an addition / subtraction unit that adds or subtracts at a given ratio.

  For example, the angular velocity signal generation unit may extract an angular velocity component from a signal generated by the vibrator based on a first detection signal synchronized with the drive signal. Further, the vibration leakage signal generation unit extracts a vibration leakage component from a signal generated by the vibrator based on a second detection signal that is synchronized with the drive signal and has a phase different from that of the first detection signal, for example. You may do it.

  According to the present invention, on the assumption that there is a correlation between the temperature characteristic of the angular velocity signal and the temperature characteristic of the vibration leakage signal, the vibration leakage signal is added to or subtracted from the angular velocity signal at a given ratio. The temperature characteristic can be corrected. Therefore, the temperature fluctuation of the angular velocity signal caused by the vibration leakage component can be compensated without using a high-order temperature compensation circuit.

  (2) The angular velocity detection device includes a first primary temperature adjustment unit that adjusts a primary component of a temperature characteristic of the angular velocity signal input to the addition / subtraction unit so as to approach a first value, and the addition / subtraction unit. And a second primary temperature adjustment unit that adjusts the primary component of the temperature characteristic of the vibration leakage signal input to the second value so as to approach the second value.

  According to the relationship between the temperature characteristic of the angular velocity signal and the temperature characteristic of the vibration leakage signal, the first value and the second value are corrected so that the temperature characteristic of the angular velocity signal is corrected by addition or subtraction in the addition / subtraction unit. Select a value. For example, when the temperature characteristic curve of the angular velocity signal and the temperature characteristic curve of the vibration leakage signal are in the same direction, the same value is selected as the first value and the second value, and the addition / subtraction unit calculates the vibration leakage signal from the angular velocity signal. You may make it subtract by a given ratio. Conversely, if the temperature characteristic curve of the angular velocity signal and the temperature characteristic curve of the vibration leakage signal are in opposite directions, the two values of the same absolute value with different signs are selected as the first value and the second value, respectively. The addition / subtraction unit may add the vibration leakage signal to the angular velocity signal at a given ratio.

  In this way, even when there is a large difference between the primary component of the temperature characteristic of the angular velocity signal and the primary component of the temperature characteristic of the vibration leakage signal, the temperature compensation of the angular velocity signal can be performed.

  (3) In this angular velocity detection device, one of the primary component of the temperature characteristic of the angular velocity signal input to the adder / subtractor and the primary component of the temperature characteristic of the vibration leakage signal input to the adder / subtractor is set to the other. You may make it include the primary temperature adjustment part adjusted so that it may approach.

  In this way, even when there is a large difference between the primary component of the temperature characteristic of the angular velocity signal and the primary component of the temperature characteristic of the vibration leakage signal, the temperature compensation of the angular velocity signal can be performed.

  (4) The angular velocity detection device may include a primary temperature correction unit that corrects a primary component of a temperature characteristic of the signal added or subtracted by the addition / subtraction unit.

  In this way, even when there is a large difference between the primary component of the temperature characteristic of the angular velocity signal and the primary component of the temperature characteristic of the vibration leakage signal, the temperature compensation of the angular velocity signal can be performed with higher accuracy.

  (5) The angular velocity detection device may include a terminal that outputs a signal based on the vibration leakage signal to the outside.

  The signal based on the vibration leakage signal may be the vibration leakage signal itself, or may include a signal obtained by performing a predetermined process such as amplification on the vibration leakage signal.

On the premise that the amplitude of the vibration leakage component is constant regardless of the angular velocity, the presence or absence of a failure of the angular velocity detection device can be recognized from the outside by monitoring the signal based on the vibration leakage signal.

  (6) The angular velocity detection device may include a failure determination unit that determines the presence or absence of a failure of the angular velocity detection device based on the vibration leakage signal.

  In this way, the angular velocity detection device can recognize the presence or absence of its own failure. Moreover, if the signal of the determination result of a failure determination part is output outside, the presence or absence of the failure of the said angular velocity detection apparatus can be recognized directly from the outside by monitoring the output signal of a failure determination part.

  (7) In this angular velocity detection device, the addition / subtraction unit is disposed in series with an inverting amplifier that inverts the polarity of an input signal, a switch circuit that selects whether to bypass the previous inverting amplifier, and the inverting amplifier. A variable gain amplifier for amplifying or attenuating an input signal with a gain that can be variably set, and whether to reverse the polarity of the vibration leakage signal by the inverting amplifier and the switch circuit and add it to the angular velocity signal And the ratio of the vibration leakage signal to be added to the angular velocity signal may be selected by the variable gain amplifier.

  In this way, it is possible to select whether or not to reverse the polarity of the vibration leakage signal by setting the connection of the switch circuit, and to amplify or attenuate the vibration leakage signal to a desired level by setting the gain of the variable gain amplifier. be able to. Therefore, even if the level and polarity of the temperature characteristic of the vibration leakage signal vary, the temperature characteristic of the angular velocity signal or a temperature characteristic obtained by inverting the polarity can be approximated. Thereby, temperature compensation of the angular velocity signal can be realized.

  (8) The present invention is an electronic device including any one of the angular velocity detection devices described above.

The figure which shows the structural example of the angular velocity detection apparatus of 1st Embodiment. The top view of the vibration piece of a gyro sensor element. The figure for demonstrating operation | movement of a gyro sensor element. The figure for demonstrating operation | movement of a gyro sensor element. The wave form diagram for demonstrating an angular velocity detection principle. The wave form diagram for demonstrating the vibration leak detection principle. The figure which shows an example of the temperature characteristic of an angular velocity signal, and the temperature characteristic of a vibration leak signal. The figure which shows an example of the temperature characteristic of an angular velocity signal, and the temperature characteristic of a vibration leak signal. The figure which shows the structural example of an addition / subtraction circuit. The figure which shows the example which correct | amends the temperature characteristic of the angular velocity signal in 1st Embodiment. The figure which shows the example which correct | amends the temperature characteristic of the angular velocity signal in 1st Embodiment. The figure which shows an example of the temperature characteristic of an angular velocity signal, and the temperature characteristic of a vibration leak signal. The figure which shows the structural example of the angular velocity detection apparatus of 2nd Embodiment. The figure which shows the structural example of a primary temperature control circuit. The figure which shows the example which correct | amends the temperature characteristic of the angular velocity signal in 2nd Embodiment. The figure which shows the structural example of the angular velocity detection apparatus of 3rd Embodiment. The figure which shows the example which correct | amends the temperature characteristic of the angular velocity signal in 3rd Embodiment. The figure which shows the structural example of the angular velocity detection apparatus of 4th Embodiment. The figure which shows the example which correct | amends the temperature characteristic of the angular velocity signal in 4th Embodiment. The functional block diagram of an electronic device.

DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. Also, not all of the configurations described below are essential constituent requirements of the present invention.

1. Angular velocity detector 1-1. First Embodiment FIG. 1 is a diagram illustrating a configuration example of an angular velocity detection device according to a first embodiment.

  The angular velocity detection device 1 of the first embodiment includes a gyro sensor element 100 and an angular velocity detection IC 10.

  The gyro sensor element 100 (an example of a vibrator) is configured by sealing a vibrating piece in which a drive electrode and a detection electrode are arranged in a package (not shown). Generally, hermeticity in the package is secured in order to reduce the impedance of the resonator element as much as possible to increase the oscillation efficiency.

The vibrating piece of the gyro sensor element 100 is, for example, a piezoelectric single crystal such as quartz (SiO ₂ ), lithium tantalate (LiTaO ₃ ), lithium niobate (LiNbO ₃ ), or piezoelectric ceramics such as lead zirconate titanate (PZT). A piezoelectric material such as zinc oxide (ZnO) or aluminum nitride (AlN) sandwiched between drive electrodes is arranged on a part of the surface of the silicon semiconductor. There may be.

  In the present embodiment, the gyro sensor element 100 is configured by a so-called double T-type vibrating piece having two T-type driving vibrating arms. However, the vibration piece of the gyro sensor element 100 may be, for example, a tuning fork type, or a sound piece type having a triangular prism shape, a quadrangular prism shape, a cylindrical shape, or the like.

  FIG. 2 is a plan view of the resonator element of the gyro sensor element 100 of the present embodiment.

  The gyro sensor element 100 of the present embodiment has a double T-type vibrating piece formed of a Z-cut quartz substrate. The resonator element made of quartz is advantageous in that the detection accuracy of the angular velocity can be increased because the variation of the resonance frequency with respect to the temperature change is extremely small. Note that the X, Y, and Z axes in FIG. 2 indicate crystal axes.

  As shown in FIG. 2, in the vibrating piece of the gyro sensor element 100, the driving vibrating arms 101a and 101b extend in the + Y axis direction and the −Y axis direction from the two driving bases 104a and 104b, respectively. Drive electrodes 112 and 113 are formed on the side surface and the upper surface of the drive vibration arm 101a, respectively, and drive electrodes 113 and 112 are formed on the side surface and the upper surface of the drive vibration arm 101b, respectively. The drive electrodes 112 and 113 are connected to the drive circuit 20 via the external output terminal 11 and the external input terminal 12 of the angular velocity detection IC 10 shown in FIG.

  The drive bases 104a and 104b are connected to a rectangular detection base 107 via connecting arms 105a and 105b extending in the −X axis direction and the + X axis direction, respectively.

  The detection vibrating arm 102 extends from the detection base 107 in the + Y axis direction and the −Y axis direction. Detection electrodes 114 and 115 are formed on the upper surface of the detection vibrating arm 102, and a common electrode 116 is formed on the side surface of the detection vibrating arm 102. The detection electrodes 114 and 115 are connected to the detection circuit 30 via the external input terminals 13 and 14 of the angular velocity detection IC 10 shown in FIG. The common electrode 116 is grounded.

  When an AC voltage is applied as a drive signal between the drive electrode 112 and the drive electrode 113 of the drive vibration arms 101a and 101b, the drive vibration arms 101a and 101b are as shown by an arrow B due to the inverse piezoelectric effect as shown in FIG. In addition, bending vibration (excitation vibration) in which the tips of the two drive vibration arms 101a and 101b repeat approach and separation from each other is performed.

  In this state, when an angular velocity with the Z axis as the rotation axis is applied to the vibrating piece of the gyro sensor element 100, the driving vibrating arms 101a and 101b are coriolis in a direction perpendicular to both the direction of the bending vibration indicated by the arrow B and the Z axis. Get the power of. As a result, the connecting arms 105a and 105b vibrate as indicated by an arrow C as shown in FIG. The detection vibrating arm 102 bends and vibrates as indicated by an arrow D in conjunction with the vibrations of the connecting arms 105a and 105b (arrow C). The phase of the bending vibration of the detection vibrating arm 102 and the bending vibration (excitation vibration) of the driving vibrating arms 101a and 101b due to the Coriolis force is shifted by 90 °.

  By the way, if the magnitude of the vibration energy or the magnitude of the vibration when the driving vibration arms 101a and 101b perform bending vibration (excitation vibration) is the same between the two driving vibration arms 101a and 101b, the driving vibration arms 101a and 101b, When the vibration energy of 101b is balanced and the angular velocity is not applied to the gyro sensor element 100, the detection vibrating arm 102 does not flex and vibrate. However, if the balance of the vibration energy of the two drive vibration arms 101a and 101b is lost, bending vibration is generated in the detection vibration arm 102 even when the angular velocity is not applied to the gyro sensor element 100. This bending vibration is called leakage vibration, and is bending vibration indicated by an arrow D like the vibration based on the Coriolis force, but is in phase with the drive signal.

  Then, AC charges based on these bending vibrations are generated in the detection electrodes 114 and 115 of the detection vibration arm 102 by the piezoelectric effect. Here, the AC charge generated based on the Coriolis force changes according to the magnitude of the Coriolis force (in other words, the magnitude of the angular velocity applied to the gyro sensor element 100). On the other hand, the AC charge generated based on the leakage vibration is constant regardless of the magnitude of the angular velocity applied to the gyro sensor element 100.

  A rectangular weight portion 103 having a width wider than that of the drive vibrating arms 101a and 101b is formed at the ends of the drive vibrating arms 101a and 101b. By forming the weight portion 103 at the tips of the drive vibrating arms 101a and 101b, the Coriolis force can be increased and a desired resonance frequency can be obtained with a relatively short vibrating arm. Similarly, a weight portion 106 wider than the detection vibrating arm 102 is formed at the tip of the detection vibrating arm 102. By forming the weight portion 106 at the tip of the detection vibrating arm 102, the AC charge generated in the detection electrodes 114 and 115 can be increased.

  As described above, the gyro sensor element 100 detects the AC charge (angular velocity component) based on the Coriolis force using the Z axis as the detection axis and the AC charge (vibration leakage component) based on the leakage vibration of the excitation vibration. 115 via the output.

Incidentally, the Coriolis force F _c applied to the gyro sensor element 100 is calculated by the following equation (1).

In equation (1), m is the equivalent mass, v is the vibration velocity, and Ω is the angular velocity. According to equation (1), even if the angular velocity Ω is constant, if the equivalent mass m or the vibration velocity v changes, the Coriolis force changes accordingly. That is, when the equivalent mass m or the vibration velocity v changes, the angular velocity detection sensitivity changes. When the vibration state of the vibration piece of the gyro sensor element 100 changes due to some failure, the detection mass changes because the equivalent mass m or vibration speed v of the drive vibration changes. At the same time, since the state of the leakage vibration also changes, the magnitude of the vibration leakage component also changes. That is, there is a correlation between the magnitude of the vibration leakage component and the detection sensitivity of the angular velocity, and by monitoring the magnitude of the vibration leakage component, it is possible to determine whether or not the gyro sensor element 100 has failed.

  Therefore, in the present embodiment, the vibration energy balance of the drive vibrating arms 101a and 101b is slightly broken so that a desired level of vibration leakage component is positively generated. In particular, in this embodiment, since the gyro sensor element 100 is configured using a double T-type vibrating piece, the weight portion 103 at the tip of the driving vibrating arm 101a and the tip of the driving vibrating arm 101b are formed by laser processing or the like. By making a difference in the mass of the weight portion 103, it is possible to easily unbalance the bending vibration of the driving vibration arm 101a and the bending vibration of the driving vibration arm 101b.

  Returning to FIG. 1, the angular velocity detection IC 10 includes a drive circuit 20, a detection circuit 30, a reference power supply circuit 40, and a memory 50.

  The drive circuit 20 includes an I / V conversion circuit (current / voltage conversion circuit) 210, an AC amplification circuit 220, and an amplitude adjustment circuit 230.

  The drive current that has flowed through the resonator element of the gyro sensor element 100 is converted into an AC voltage signal by the I / V conversion circuit 210.

  The AC voltage signal output from the I / V conversion circuit 210 is input to the AC amplifier circuit 220 and the amplitude adjustment circuit 230. The AC amplifier circuit 220 amplifies the input AC voltage signal, clips it with a predetermined voltage value, and outputs the square wave voltage signal 22. The amplitude adjustment circuit 230 changes the amplitude of the square wave voltage signal 22 in accordance with the level of the AC voltage signal output from the I / V conversion circuit 210, and controls the AC amplification circuit 220 so that the drive current is kept constant. To do.

  The square wave voltage signal 22 is supplied to the drive electrode 112 of the vibrating piece of the gyro sensor element 100 via the external output terminal 11. In this way, the gyro sensor element 100 continuously excites predetermined driving vibration as shown in FIG. Further, by keeping the drive current constant, the drive vibrating arms 101a and 101b of the gyro sensor element 100 can obtain a constant vibration speed. For this reason, the vibration speed that generates the Coriolis force is constant, and the sensitivity can be further stabilized.

  The detection circuit 30 includes charge amplifiers 310 and 312, a differential amplification circuit 320, an AC amplification circuit 330, a phase shift circuit 340, synchronous detection circuits 350 and 352, integration circuits 360 and 362, an addition / subtraction circuit 370, and DC amplification circuits 380 and 382. It is comprised including.

  An AC charge including an angular velocity component and a vibration leakage component is input to the charge amplifier 310 from the detection electrode 114 of the vibration piece of the gyro sensor element 100 via the external input terminal 13.

  Similarly, the charge amplifier 312 receives AC charges including an angular velocity component and a vibration leakage component from the detection electrode 115 of the vibrating piece of the gyro sensor element 100 via the external input terminal 14.

The charge amplifiers 310 and 312 convert the input AC charges into AC voltage signals based on the reference voltage _Vref . Note that the reference voltage V _ref is equal to the reference power supply circuit 4.
0 is generated based on the external power supply input from the power input terminal 15.

  The differential amplifier circuit 320 differentially amplifies the output signal of the charge amplifier 310 and the output signal of the charge amplifier 312. The differential amplifier circuit 320 is for erasing in-phase components and adding and amplifying anti-phase components.

  The AC amplifier circuit 330 amplifies the output signal of the differential amplifier circuit 330. The output signal of the AC amplifier circuit 330 includes an angular velocity component and a vibration leakage component, and is input to the synchronous detection circuits 350 and 352 as the detected signal 33.

The synchronous detection circuit 350 performs synchronous detection on the detected signal 33 using the square voltage signal 22 as a detection signal. For example, when the voltage level of the square wave voltage signal 22 is higher than the reference voltage V _ref , the synchronous detection circuit 350 selects the detected signal 33 and the voltage level of the square wave voltage signal 22 is lower than the reference voltage V _ref. In some cases, it can be configured as a switch circuit that selects a signal obtained by inverting the detected signal 33 with respect to the reference voltage _Vref .

The synchronous detection circuit 352 performs synchronous detection on the detected signal 33 using the square wave voltage signal 34 obtained by delaying the phase of the square wave voltage signal 22 by 90 ° by the phase circuit 340 as a detection signal. For example, the synchronous detection circuit 352 selects the detected signal 33 when the voltage level of the square wave voltage signal 34 is higher than the reference voltage V _ref , and the voltage level of the square wave voltage signal 34 is lower than the reference voltage V _ref. In some cases, it can be configured as a switch circuit that selects a signal obtained by inverting the detected signal 33 with respect to the reference voltage _Vref .

  The output signal of the synchronous detection circuit 350 is smoothed into a DC voltage signal by the integration circuit 360 and input to the addition / subtraction circuit 370 as the angular velocity signal 36a.

  The output signal of the synchronous detection circuit 352 is smoothed into a DC voltage signal by the integration circuit 362 and input to the addition / subtraction circuit 370 and the DC amplification circuit 382 as the vibration leakage signal 36b.

  The addition / subtraction circuit 370 adds or subtracts the vibration leakage signal 36b to the angular velocity signal 36a at a preset ratio.

  The DC amplifier circuit 380 amplifies or attenuates the angular velocity signal 37 whose temperature characteristics have been corrected by the addition / subtraction circuit 370 to a desired level, and outputs the amplified angular velocity signal 38a to the outside as the angular velocity signal 38a. An external device (not shown) can obtain angular velocity information by monitoring the angular velocity signal 38a.

  The DC amplification circuit 382 amplifies or attenuates the vibration leakage signal 36b to a desired level, and outputs the vibration leakage signal 36b to the outside through the external output terminal 17 as the vibration leakage signal 38b. And an external device (not shown) can determine the presence or absence of a failure such as a failure or disconnection of the gyro sensor element 100 by monitoring the vibration leakage signal 38b.

  Further, a failure determination circuit 60 that determines a failure of the angular velocity detection device 1 may be incorporated in the angular velocity detection IC 10. The failure determination circuit 60 determines whether or not the angular velocity detection device 1 has failed based on the vibration leakage signal 36b, and outputs a failure determination signal 62 to the outside via the external output terminal 18. For example, the failure determination circuit 60 may determine that the vibration leakage signal 36b is normal (no failure) if the amplitude of the vibration leakage signal 36b is within a predetermined range, and may determine that there is a failure if the amplitude is not within the predetermined range. Since the amplitude of the vibration leak signal 36b varies from sample to sample, a reference value for failure determination may be stored in the memory 50.

  The drive circuit 20 functions as a drive unit in the present invention. Further, the configuration of the synchronous detection circuit 350 and the integration circuit 360 functions as an angular velocity signal generation unit in the present invention. However, the synchronous detection circuit 350 and its output signal may correspond to the angular velocity signal generator and the angular velocity signal in the present invention, respectively. The configuration of the synchronous detection circuit 352 and the integration circuit 362 functions as a vibration leakage signal generation unit in the present invention. However, the synchronous detection circuit 352 and its output signal may correspond to the vibration leakage signal generator and the vibration leakage signal in the present invention, respectively. The addition / subtraction circuit 370 functions as an addition / subtraction unit in the present invention. Moreover, the failure determination circuit 60 functions as a failure determination unit in the present invention.

  Next, the principle of angular velocity detection of the angular velocity detection device shown in FIG. 1 will be described using the waveform diagram of FIG. FIG. 5 is a diagram illustrating an example of signal waveforms at points A to J in FIG. 1, where the horizontal axis represents time and the vertical axis represents voltage.

  In a state where the vibrating piece of the gyro sensor element 100 is vibrating, the current fed back from the drive electrode 113 of the vibrating piece of the gyro sensor element 100 is converted into the output (point A) of the I / V conversion circuit 210. An AC voltage with a constant frequency is generated. That is, a sine wave voltage signal having a constant frequency is generated at the output (point A) of the I / V conversion circuit 210.

Then, the output of the AC amplifier circuit 220 (B point), the output signal of the I / V conversion circuit 210 (signal point A) is amplified, the square wave voltage signal 22 amplitude is a constant value _{V c} is generated .

  When an angular velocity is applied to the gyro sensor element 100, signals generated at the detection electrodes 114 and 115 of the vibrating piece of the gyro sensor element 100 include an angular velocity component and a vibration leakage component. The magnitude of this angular velocity component changes according to the magnitude of the Coriolis force. On the other hand, the vibration leakage component has a constant magnitude regardless of the magnitude of the angular velocity. However, since the purpose is to explain the detection principle of the angular velocity in FIG. 5, a signal waveform focusing only on the angular velocity component is shown, and in the following description, description will be made focusing on only the angular velocity component.

  The angular velocity components (AC charges) of the signals generated at the detection electrodes 114 and 115 of the vibrating piece of the gyro sensor element 100 are converted into AC voltage signals by the charge amplifiers 310 and 312 respectively. As a result, a sine wave voltage signal having the same frequency as the output signal (point B signal) of the AC amplifier circuit 220 is generated at the outputs (point C and point D) of the charge amplifiers 310 and 312. Here, the phase of the output signal of the charge amplifier 310 (point C signal) is the same as that of the output signal of the AC amplifier circuit 220 (point B signal). The phase of the output signal (point D signal) of the charge amplifier 312 is opposite to that of the output signal (point C signal) of the charge amplifier 310 (shifted by 180 °).

  The output signals of the charge amplifiers 310 and 312 (point C signal and point D signal) are differentially amplified by the differential amplifier circuit 320, and the output (point E) of the AC amplifier circuit 330 is output to the output of the charge amplifier 310 (point E). A sine wave voltage signal having the same frequency and the same phase as the sine wave voltage signal generated at point C) is generated. The sine wave voltage signal generated at the output (point E) of the AC amplifier circuit 330 is a signal obtained by amplifying the angular velocity component of the signal generated at the detection electrodes 114 and 115 of the gyro sensor element 100.

The output signal (point E signal) of the AC amplifier circuit 330 is synchronously detected by the synchronous detection circuit 350 based on the square wave voltage signal 22. Here, since the output signal of the AC amplifier circuit 330 (the signal at the point E) and the square wave voltage signal 22 (the signal at the point B) are in phase, the output signal of the synchronous detection circuit 350 (the signal at the point G) is The output signal of the AC amplifier circuit 330 (the signal at point E) is a full-wave rectified signal. As a result, the output of the integrating circuit 360 (H point), the DC voltage signal of the voltage value V ₁ corresponding to the magnitude of the angular velocity (angular velocity signal 36a) is generated.

On the other hand, the output of the phase shift circuit 340 (point F) generates a square wave voltage signal 34 whose phase is delayed by 90 ° with respect to the square wave voltage signal 22 (point B signal). The signal (signal at point E) is synchronously detected based on the square wave voltage signal 34 by the synchronous detection circuit 352. Here, since the output signal (point E signal) of the AC amplifier circuit 330 and the square wave voltage signal 34 (point F signal) are 90 ° out of phase, the output signal of the synchronous detection circuit 352 (point I signal). in), the integration of integrated amount and the reference voltage lower than the voltage V _ref of the voltage higher than the reference voltage V _ref is equal. As a result, the angular velocity component is canceled and a DC voltage signal of the reference voltage V _ref is generated at the output (point J) of the integrating circuit 362.

When an angular velocity in the direction opposite to that in FIG. 5 is applied to the angular velocity detector 1, both the output signal of the charge amplifier 310 (point C signal) and the output signal of the charge amplifier 312 (point D signal) are both the reference voltage. The waveform is inverted around V _ref . As a result, the angular velocity signal 36a (point H signal) is a signal having a voltage lower than the reference voltage _Vref, contrary to FIG. Since the voltage value of the angular velocity signal 36a is proportional to the magnitude of the Coriolis force (angular velocity magnitude) and its polarity is determined by the rotation direction, the angular velocity applied to the angular velocity detecting device 1 is calculated based on the angular velocity signal 36a. can do.

  Next, the principle of vibration leakage detection of the angular velocity detection device shown in FIG. 1 will be described with reference to the waveform diagram of FIG. FIG. 6 is a diagram illustrating an example of signal waveforms at points A to J in FIG. 1, where the horizontal axis represents time and the vertical axis represents voltage.

  In FIG. 6, signal waveforms at points A, B, and F are the same as those in FIG. In addition, since the purpose of explaining the principle of detection of vibration leakage is shown in FIG. 6, signal waveforms that focus only on the vibration leakage component are shown. In the following description, only the vibration leakage component will be described. .

  The vibration leakage components (AC charges) of the signals generated at the detection electrodes 114 and 115 of the vibrating piece of the gyro sensor element 100 are converted into AC voltage signals by the charge amplifiers 310 and 312 respectively. As a result, a sine wave voltage signal having the same frequency as the output signal (point B signal) of the AC amplifier circuit 220 is generated at the outputs (point C and point D) of the charge amplifiers 310 and 312. Here, the phase of the output signal of the charge amplifier 310 (point C signal) is shifted by 90 ° with respect to the output signal of the AC amplifier circuit 220 (point B signal). The phase of the output signal (point D signal) of the charge amplifier 312 is opposite to that of the output signal (point C signal) of the charge amplifier 310 (shifted by 180 °).

  The output signals of the charge amplifiers 310 and 312 (point C signal and point D signal) are differentially amplified by the differential amplifier circuit 320, and the output (point E) of the AC amplifier circuit 330 is output to the output of the charge amplifier 310 (point E). A sine wave voltage signal having the same frequency and the same phase as the sine wave voltage signal generated at point C) is generated. This sine wave voltage signal generated at the output (point E) of the AC amplifier circuit 330 is a signal obtained by amplifying the vibration leakage component of the signal generated at the detection electrodes 114 and 115 of the gyro sensor element 100.

The output signal (point E signal) of the AC amplifier circuit 330 is synchronously detected by the synchronous detection circuit 350 based on the square wave voltage signal 22. Here, since the output signal (point E signal) of the AC amplifier circuit 330 and the square wave voltage signal 22 (point B signal) are 90 ° out of phase, the output signal of the synchronous detection circuit 350 (point G signal). in), the integration of integrated amount and the reference voltage lower than the voltage V _ref of the voltage higher than the reference voltage V _ref is equal. As a result, the vibration leakage component is canceled and a DC voltage signal of the reference voltage V _ref is generated at the output (point H) of the integration circuit 360.

On the other hand, the output signal (signal at point E) of the AC amplifier circuit 330 is synchronously detected by the synchronous detection circuit 352 based on the square wave voltage signal 34. Here, since the output signal of the AC amplifier circuit 330 (point E signal) and the square wave voltage signal 34 (point F signal) are in phase, the output signal of the synchronous detection circuit 352 (point I signal) is The output signal of the AC amplifier circuit 330 (the signal at point E) is a full-wave rectified signal. As a result, the output of the integrating circuit 362 (J point), the DC voltage signal of the voltage value V ₂ corresponding to the magnitude of the vibration leakage component (vibration leakage signal 36b) is generated.

  The voltage value of the vibration leakage signal 36b is proportional to the magnitude of the vibration leakage component, but if there is no failure, the magnitude of the vibration leakage component is constant. Therefore, the failure of the angular velocity detection device 1 is monitored by monitoring the vibration leakage signal 36b. The presence or absence of can be determined.

  5 and 6, the ideal detection principle has been described on the assumption that the vibration energy of the drive vibrating arms 101a and 101b is balanced and the phase is accurately delayed by 90 ° in the phase shift circuit 340. Actually, the balance of vibration energy varies for each gyro sensor element, and the phase delayed by the phase shift circuit 340 also varies for each IC. As a result, the vibration leakage component is detected by the synchronous detection circuit 350, and the angular velocity signal 36a has an offset accordingly. If the offset is constant regardless of the temperature, it can be corrected by an offset adjustment circuit (0 point adjustment circuit) (not shown). However, since the temperature characteristics of the angular velocity signal 36a are not flat, the angular velocity detection apparatus 1 of the present embodiment corrects the temperature characteristics of the angular velocity signal 36a by providing an addition / subtraction circuit 370 after the integration circuit 360. Specifically, paying attention to the correlation between the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b, the addition / subtraction circuit 370 corrects the temperature characteristic of the angular velocity signal 36a using the vibration leakage signal 36b. Yes.

  7A to 7C and FIGS. 8A to 8C, the angular velocity detection device 1 is stationary (the angular velocity is not applied) for six samples of the angular velocity detection device 1. ) Is a diagram showing an example of the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b. In each figure, the horizontal axis represents time, and the vertical axis represents voltage. Moreover, in each figure, a continuous line shows the temperature characteristic of the angular velocity signal 36a, and a broken line shows the temperature characteristic of the vibration leakage signal 36b.

In the three samples of FIGS. 7A, 7B, and 7C, the temperature characteristic curve of the angular velocity signal 36a is similar to the temperature characteristic curve of the vibration leakage signal 36b. On the other hand, in the three samples of FIG. 8A, FIG. 8B, and FIG. 8C, if the voltage value of the vibration leakage signal 36b is inverted with respect to the reference voltage _Vref , the temperature characteristics of the angular velocity signal 36a. The curve and the temperature characteristic curve of the vibration leakage signal 36b are similar. However, it can also be seen that the voltage difference between the two curves varies between samples. Therefore, considering the similarity between the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b, the temperature characteristic of the angular velocity signal 36a can be corrected by using the vibration leakage signal 36b.

  FIG. 9 is a diagram illustrating a configuration example of an addition / subtraction circuit 370 capable of correcting the temperature of the angular velocity signal 36a. As shown in FIG. 9, the addition / subtraction circuit 370 can be configured using, for example, a switch circuit 372, an inverting amplifier 374, a variable gain amplifier 376, and an adder 378.

In response to the selection signal 52, the switch circuit 372 selects which of the inverting amplifier 374 and the variable gain amplifier 376 inputs the vibration leakage signal 36b. For example, a switch setting bit may be stored in the memory 50 in advance, and this bit may be supplied to the switch circuit 372 as the selection signal 52. When the vibration leakage signal 36b is input to the inverting amplifier 374, the polarity of the vibration leakage signal 36b is inverted by the inverting amplifier 374 (the voltage value is inverted with reference to the reference voltage _Vref ) and input to the variable gain amplifier 376. The That is, the switch circuit 372 selects whether to bypass the inverting amplifier 374. By switching the switch circuit 372, the vibration leakage signal 36b is input to the variable gain amplifier 376 as it is, or the vibration leakage signal 36b. Can be selected to be inverted and input to the variable gain amplifier 376.

  The variable gain amplifier 376 is an inverting amplifier that amplifies or attenuates an input signal with a gain corresponding to the selection signal 54. For example, gain setting data may be stored in the memory 50 in advance, and each bit of the data may be supplied to the variable gain amplifier 376 as the selection signal 54.

  The adder 378 adds the angular velocity signal 36 a and the output signal of the variable gain amplifier 376 to generate the angular velocity signal 37.

  When the adder / subtracter circuit 370 has the configuration shown in FIG. 9, if the temperature characteristics of the angular velocity signal 36a and the temperature characteristics of the vibration leakage signal 36b are similar to those shown in FIGS. By setting the selection signal 52 so as to bypass the inverting amplifier 374 and selecting an appropriate value as the gain of the variable gain amplifier 376 according to the setting of the selection signal 54, the temperature characteristic of the angular velocity signal 37 is made close to flat. be able to. For example, the temperature characteristics of the angular velocity signal 36a (the signal at point H in FIG. 1) and the temperature characteristics of the vibration leakage signal 36b (the signal at point J in FIG. 1) are as shown in FIGS. 10A and 10B, respectively. Suppose that At this time, the vibration leakage signal 36b is directly input to the variable gain amplifier 376 and its polarity is inverted, so that the temperature characteristic of the output signal of the variable gain amplifier 376 (the output signal at the point K in FIG. 9) is as shown in FIG. ). Therefore, the angular velocity signal 37 (FIG. 1 and FIG. 1) obtained by adding the output signal (point K output signal of FIG. 9) of the variable gain amplifier 376 to the angular velocity signal 36a (point H signal of FIG. 1) by the adder 378. The temperature characteristic of the output signal at point L of 9 is almost flat as shown in FIG.

  On the other hand, if the temperature characteristics of the angular velocity signal 36a and the temperature characteristics of the vibration leakage signal 36b are as shown in FIGS. 8A to 8C, for example, the switch circuit 372 is selected not to bypass the inverting amplifier 374. By setting the signal 52 and selecting an appropriate value as the gain of the variable gain amplifier 376 by setting the selection signal 54, the temperature characteristics of the angular velocity signal 37 can be made flat. For example, the temperature characteristics of the angular velocity signal 36a (point H signal in FIG. 1) and the temperature characteristics of the vibration leakage signal 36b (point J signal in FIG. 1) are shown in FIGS. 11A and 11B, respectively. Suppose that At this time, since the polarity of the vibration leakage signal 36b is inverted by the inverting amplifier 374 and further inverted by the variable gain amplifier 376, the temperature of the output signal of the variable gain amplifier 376 (the output signal at the point K in FIG. 9). The characteristics are as shown in FIG. Therefore, the angular velocity signal 37 (FIG. 1 and FIG. 1) obtained by adding the output signal (point K output signal of FIG. 9) of the variable gain amplifier 376 to the angular velocity signal 36a (point H signal of FIG. 1) by the adder 378. As shown in FIG. 11D, the temperature characteristic of the output signal at point L of 9 is nearly flat.

As described above, according to the angular velocity detection device of the first embodiment, when the temperature characteristics of the angular velocity signal 36a and the temperature characteristics of the vibration leakage signal 36b are similar, a polarity of the vibration leakage signal 36b is obtained. Is inverted and added to the angular velocity signal 36a at a given ratio, the temperature characteristic curve of the angular velocity signal 37 can be made nearly flat. When the temperature characteristics of the angular velocity signal 36a and the temperature characteristics of the vibration leakage signal 36b draw opposite curves, the polarity of the vibration leakage signal 36b is not inverted but added to the angular velocity signal 36a at a given ratio. Thus, the temperature characteristic curve of the angular velocity signal 37 can be made nearly flat. Further, even when the temperature characteristics of the angular velocity signal 36a and the temperature characteristics of the vibration leakage signal 36b draw different curves, it is possible to adjust the gain of the variable gain amplifier 376 so that the angular velocity signal 37 can be adjusted. It is possible to select an optimum gain that makes the temperature characteristic curve flat.

  That is, according to the angular velocity detection device of the first embodiment, it is possible to compensate for the temperature fluctuation of the angular velocity signal caused by the vibration leakage component of the vibrator without using a high-order temperature compensation circuit.

  9 may be modified such that the switch circuit 372 and the inverting amplifier 374 are moved to the subsequent stage of the variable gain amplifier 376, or the variable gain amplifier 376 is changed to a non-inverting amplifier. The logic of the selection signal 52 to be inputted may be modified so as to be opposite to that in the case of FIG. 1, the output signal of the synchronous detection circuit 350 and the output signal of the synchronous detection circuit 352 may be input to the adder / subtracter circuit 370, and the integration circuit 360 may be arranged at the subsequent stage of the adder / subtractor circuit 370.

1-2. Second Embodiment In the examples of FIGS. 7A to 7C and FIGS. 8A to 8C, the temperature characteristics of the angular velocity signal 36a and the temperature characteristics of the vibration leakage signal 36b are quite similar. However, an example of another temperature characteristic having a different tendency from these is shown in FIG. In FIG. 12, the horizontal axis represents time, and the vertical axis represents voltage. In FIG. 12, the solid line shows the temperature characteristic of the angular velocity signal 36a, and the broken line shows the temperature characteristic of the vibration leakage signal 36b.

  In the sample of FIG. 12, there is not much difference between the secondary component and the tertiary component of the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b, but there is a large difference in the primary component. Therefore, in this sample, even if the angular velocity signal 36a and the vibration leakage signal 36b are input to the addition / subtraction circuit 370, the temperature characteristic of the angular velocity signal 37 does not become flat. Therefore, with respect to the configuration of FIG. 1, an adjustment is made so that the primary component of the temperature characteristic of the angular velocity signal 36 a and the primary component of the temperature characteristic of the vibration leakage signal 36 b approach the same value, and then input to the addition / subtraction circuit 370. It is considered effective to add or subtract.

  FIG. 13 is a diagram illustrating a configuration example of the angular velocity detection device of the second embodiment. In FIG. 13, the same components as those in FIG.

  In the angular velocity detection device 1 of the second embodiment, primary temperature adjustment circuits 390 and 392 are added to the configuration of FIG. Further, a temperature sensor 70 is added. The temperature sensor 70 may be added to the outside of the angular velocity detection IC 10.

  The temperature sensor 70 outputs a temperature detection signal 72 having a voltage value linear with respect to the temperature. This temperature detection signal 72 is input to the primary temperature adjustment circuits 390 and 392.

  The primary temperature adjustment circuit 390 uses the temperature detection signal 72 to adjust so that the primary component of the temperature characteristic of the angular velocity signal 36a approaches the first value. Further, the primary temperature adjustment circuit 392 uses the temperature detection signal 72 to adjust the primary component of the temperature characteristic of the vibration leakage signal 36b so as to approach the second value. The first value and the second value may be the same value. For example, if 0 is selected as both the first value and the second value, the primary temperature adjustment circuits 390 and 392 cancel the primary components of the temperature characteristics of the angular velocity signal 36a and the vibration leakage signal 36b, respectively. Functions as a secondary temperature correction circuit. However, other than 0 may be selected as the first value and the second value.

  The primary temperature adjustment circuits 390 and 392 can be realized by a circuit having the same configuration. FIG. 14 is a diagram illustrating a configuration example of the primary temperature adjustment circuit 390 (392). As shown in FIG. 14, the primary temperature adjustment circuit 390 (392) can be configured using, for example, a switch circuit 394, an inverting amplifier 395, a variable gain amplifier 396, and an adder 397.

  In response to the selection signal 56, the switch circuit 394 selects which of the inverting amplifier 395 and the variable gain amplifier 396 inputs the temperature detection signal 72. For example, a switch setting bit may be stored in the memory 50 in advance, and this bit may be supplied to the switch circuit 394 as the selection signal 56. When the temperature detection signal 72 is input to the inverting amplifier 395, the polarity of the temperature detection signal 72 is inverted by the inverting amplifier 395 and input to the variable gain amplifier 396. That is, the switch circuit 394 selects whether to bypass the inverting amplifier 395. By switching the switch circuit 394, the temperature detection signal 72 is input to the variable gain amplifier 396 as it is, or the temperature detection signal 72 Can be selected to be inverted and input to the variable gain amplifier 396.

  The variable gain amplifier 396 is an inverting amplifier that amplifies or attenuates the input signal with a gain corresponding to the selection signal 58. For example, gain setting data may be stored in the memory 50 in advance, and each bit of this data may be supplied to the variable gain amplifier 396 as the selection signal 58.

  The adder 397 adds the angular velocity signal 36a or vibration leakage signal 36b and the output signal of the variable gain amplifier 396 to generate the angular velocity signal 39a or vibration leakage signal 39b.

  Then, the angular velocity signal 39a and the vibration leakage signal 39b are input to, for example, the addition / subtraction circuit 370 having the configuration shown in FIG. 9, and the angular velocity signal 37 whose temperature characteristics are corrected is generated.

  The primary temperature adjustment circuits 390 and 392 function as a first primary temperature adjustment unit and a second primary temperature adjustment unit in the present invention, respectively.

  When the primary temperature adjustment circuit 390 (392) is configured as shown in FIG. 14, the polarity (positive or negative) of the temperature characteristic slope (primary component) of the angular velocity signal 36a (vibration leakage signal 36b) is the temperature detection signal 72. The selection signal 56 is set so that the switch circuit 394 bypasses the inverting amplifier 395 if the polarity is the same as the polarity of the slope (positive or negative). On the other hand, if the polarity (positive or negative) of the gradient (primary component) of the temperature characteristic of the angular velocity signal 36a (vibration leakage signal 36b) is opposite to the polarity (positive or negative) of the gradient with respect to the temperature of the temperature detection signal 72, The selection signal 56 is set so that the switch circuit 394 does not bypass the inverting amplifier 395. Then, by selecting an appropriate value as the gain of the variable gain amplifier 396 by setting the selection signal 58, the primary component of the temperature characteristic of the angular velocity signal 39a (vibration leakage signal 39b) is changed to the first value (second value). ).

For example, the temperature characteristics of the angular velocity signal 36a (point H signal in FIG. 13) and the temperature characteristics of the vibration leakage signal 36b (point J signal in FIG. 13) are shown by solid lines in FIGS. 15A and 15B, respectively. Suppose that it is as shown. Further, it is assumed that the temperature detection signal 72 (the signal at the point Z in FIG. 13) has a negative slope with respect to the temperature as shown in FIG. At this time, since the primary component of the temperature characteristic of the angular velocity signal 36a (the broken line in FIG. 15A) is positive, the temperature detection signal 72 passes through the variable gain amplifier 396 and the variable gain amplifier 396 of the primary temperature adjustment circuit 390. To the adder 397. As a result, the temperature characteristics of the angular velocity signal 39a (the signal at point M in FIG. 13) are as shown in FIG. 15D, and the primary component (broken line in FIG. 15D) is the first value (for example, 0). ) Is adjusted. On the other hand, since the primary component of the temperature characteristic of the vibration leakage signal 36b (broken line in FIG. 15B) is negative, the temperature detection signal 72 is sent to the adder 397 via the variable gain amplifier 396 of the primary temperature adjustment circuit 392. Entered. As a result, the temperature characteristic of the vibration leakage signal 39b (the signal at point N in FIG. 13) is as shown in FIG. 15E, and the primary component (broken line in FIG. 15E) is the second value (for example, 0). Then, the angular velocity signal 39a (the signal at the point M in FIG. 13) and the vibration leakage signal 39b (the signal at the point N in FIG. 13) are input to the addition / subtraction circuit 370, and the angular velocity signal 37 is obtained.
The temperature characteristic of (the signal at point L in FIG. 13) is nearly flat as shown in FIG. 15 (F).

  As described above, according to the angular velocity detection device of the second embodiment, even when there is a difference between the primary component of the temperature characteristic of the angular velocity signal 36a and the primary component of the temperature characteristic of the vibration leakage signal 36b, After the temperature adjustment circuits 390 and 392 adjust the values of both primary components so as to approach (ideally match), the temperature correction of the angular velocity signal by the addition / subtraction circuit 370 can be performed. Therefore, as compared with the first embodiment, correction can be made for more various combinations of the primary component of the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b.

  14, the switch circuit 394 and the inverting amplifier 395 may be modified so as to move to the subsequent stage of the variable gain amplifier 396. Alternatively, the variable gain amplifier 396 may be changed to a non-inverting amplifier so that the switch circuit 394 is replaced. The logic of the selection signal 56 to be inputted may be modified so as to be opposite to that shown in FIG. In FIG. 13, the primary temperature adjustment circuit 390 may be modified to be disposed between the synchronous detection circuit 350 and the integration circuit 360. Similarly, the primary temperature adjustment circuit 392 may be modified to be disposed between the synchronous detection circuit 352 and the integration circuit 362.

1-3. Third Embodiment FIG. 16 is a diagram illustrating a configuration example of an angular velocity detection device according to a third embodiment. In FIG. 16, the same components as those in FIG. 13 are denoted by the same reference numerals, and the description thereof is omitted.

  In the angular velocity detection device 1 of the third embodiment, the primary temperature adjustment circuit 390 is omitted from the configuration of FIG. Instead, the primary temperature adjustment circuit 392 adjusts the primary component of the temperature characteristic of the vibration leakage signal 36b to be close to the primary component of the temperature characteristic of the angular velocity signal 36a based on the temperature detection signal 72. The primary temperature adjustment circuit 392 can be configured in the same manner as in FIG. The primary temperature adjustment circuit 392 functions as a primary temperature adjustment unit in the present invention.

  The temperature characteristics of the angular velocity signal 36a (point H signal in FIG. 16) and the temperature characteristics of the vibration leakage signal 36b (point J signal in FIG. 16) are, for example, solid lines in FIGS. 17A and 17B, respectively. It is assumed that Further, it is assumed that the temperature detection signal 72 (the signal at the point Z in FIG. 16) has a negative slope with respect to the temperature as shown in FIG. At this time, for example, the temperature detection signal 72 is input to the adder 397 via the variable gain amplifier 396 to invert the polarity of the temperature detection signal 72 and then added to the vibration leakage signal 36b by the adder 397. As a result, the temperature characteristic of the vibration leakage signal 39b (point N signal in FIG. 16) is as shown in FIG. 17D, and the primary component (broken line in FIG. 17D) is converted to the angular velocity signal 36a (FIG. 16). The signal can be approximated to the primary component of the temperature characteristic (the broken line in FIG. 17A). Then, the angular velocity signal 36a (the signal at point H in FIG. 16) and the vibration leakage signal 39b (the signal at point N in FIG. 16) are input to the addition / subtraction circuit 370, and the angular velocity signal 37 (the signal at point L in FIG. 16) The temperature characteristics are almost flat as shown in FIG.

  As described above, according to the angular velocity detection device of the third embodiment, even when there is a difference between the primary component of the temperature characteristic of the angular velocity signal 36a and the primary component of the temperature characteristic of the vibration leakage signal 36b, After the temperature adjustment circuit 392 adjusts the primary component of the temperature characteristic of the vibration leakage signal 39b so as to approach (ideally match) the primary component of the temperature characteristic of the angular velocity signal 36a, the addition / subtraction circuit 370 The temperature correction of the angular velocity signal can be performed. Therefore, as compared with the first embodiment, correction can be made for more various combinations of the primary component of the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b.

In FIG. 16, the primary temperature adjustment circuit 392 is replaced with a synchronous detection circuit 352 and an integration circuit 36.
You may deform | transform into the structure arrange | positioned between two. 16, the primary temperature adjustment circuit 392 is moved between the integration circuit 360 and the addition / subtraction circuit 370 or between the synchronous detection circuit 350 and the integration circuit 360, and the temperature characteristic of the angular velocity signal is changed. You may deform | transform so that a primary component may approximate the primary component of the temperature characteristic of a vibration leak signal.

1-4. Fourth Embodiment FIG. 18 is a diagram illustrating a configuration example of an angular velocity detection device according to a fourth embodiment. In FIG. 18, the same components as those in FIG. 13 are denoted by the same reference numerals, and description thereof is omitted.

  In the angular velocity detection device 1 of the fourth embodiment, primary temperature adjustment circuits 390 and 392 are deleted from the configuration of FIG. 13, and a primary temperature correction circuit 398 is added after the addition / subtraction circuit 370. The primary temperature correction circuit 398 corrects the primary component of the temperature characteristic of the angular velocity signal 37 based on the temperature detection signal 72. The primary temperature correction circuit 398 can be configured in the same manner as in FIG. The primary temperature correction circuit 398 functions as a primary temperature correction unit in the present invention.

  The temperature characteristics of the angular velocity signal 36a (point H signal in FIG. 18) and the temperature characteristics of the vibration leakage signal 36b (point J signal in FIG. 18) are, for example, solid lines in FIGS. 19A and 19B, respectively. It is assumed that Further, it is assumed that the temperature detection signal 72 (the signal at the point Z in FIG. 18) has a negative slope with respect to the temperature as shown in FIG. 19C. At this time, for example, when the vibration leakage signal 36b is input to the variable gain amplifier 376 by bypassing the inverting amplifier 374, the temperature characteristic of the output signal of the variable gain amplifier 376 (the output signal at the point K in FIG. 9) is As shown in FIG. 19D, the polarity of the temperature characteristic (FIG. 19B) of the vibration leakage signal 36b is inverted and amplified or attenuated according to the gain of the variable gain amplifier 376. Therefore, the temperature characteristic of the angular velocity signal 37 (the output signal at point L in FIGS. 1 and 9) obtained by adding the output signal of the variable gain amplifier 376 to the angular velocity signal 36a by the adder 378 is shown in FIG. As shown, the secondary and higher components are almost canceled and the primary component remains. The temperature characteristics of the angular velocity signal 39c (the signal at the point O in FIG. 18) obtained by correcting the primary component of the temperature characteristics of the angular velocity signal 37 by the primary temperature correction circuit 398, as shown in FIG. It will be almost flat.

  As described above, according to the angular velocity detection device of the fourth embodiment, even when there is a difference between the primary component of the temperature characteristic of the angular velocity signal 36a and the primary component of the temperature characteristic of the vibration leakage signal 36b, the addition / subtraction circuit. The primary temperature correction circuit 398 can correct the primary component of the temperature characteristic of the angular velocity signal that remains uncorrected by the temperature correction by 370. Therefore, as compared with the first embodiment, correction can be made for more various combinations of the primary component of the temperature characteristic of the angular velocity signal 36a and the temperature characteristic of the vibration leakage signal 36b.

2. Electronic Device FIG. 20 is a functional block diagram illustrating a configuration example of the electronic device of the present embodiment. The electronic device 500 of this embodiment includes an angular velocity detection device 600, a CPU 700, an operation unit 710, a display unit 720, a ROM (Read Only Memory) 730, a RAM (Random Access Memory) 740, and a communication unit 750. . Note that the electronic apparatus of the present embodiment may be configured such that some of the components (each unit) in FIG. 20 are omitted or other components are added.

  The angular velocity detection device 600 generates an angular velocity signal having a voltage corresponding to the angular velocity and outputs it to the CPU 700. Further, the angular velocity detection device 600 may generate a vibration leakage signal having a voltage corresponding to the magnitude of the vibration leakage caused by the excitation vibration of the vibrator and output it to the CPU 700.

The CPU 700 performs various calculation processes and control processes in accordance with programs stored in the ROM 730. Specifically, the CPU 700 controls the angular velocity detection device 600 or receives an angular velocity signal from the angular velocity detection device 600 and performs various calculation processes. In addition, the CPU 700 uses the communication unit 750 to perform various processes in accordance with operation signals from the operation unit 710, to transmit display signals for displaying various types of information on the display unit 720, and to perform data communication with the outside. Performs control processing and the like.

  The operation unit 710 is an input device including operation keys, button switches, and the like, and outputs an operation signal corresponding to an operation by the user to the CPU 700.

  The display unit 720 is a display device configured by an LCD (Liquid Crystal Display) or the like, and displays various types of information based on a display signal input from the CPU 700.

  The ROM 730 stores programs for the CPU 700 to perform various calculation processes and control processes, various programs and data for realizing a navigation function, and the like.

  The RAM 740 is used as a work area of the CPU 700, and temporarily stores programs and data read from the ROM 730, data input from the operation unit 710, calculation results executed by the CPU 700 according to various programs, and the like.

  The communication unit 750 performs various controls for establishing data communication between the CPU 700 and an external device.

  By incorporating the angular velocity detection device according to the present embodiment into the electronic apparatus 500 as the angular velocity detection device 600, it is possible to realize processing with relatively high accuracy at a low cost.

  Various electronic devices using an angular velocity detection device can be considered as the electronic device 600. For example, a vehicle skidding prevention device, a rollover detection device, a mobile phone, a navigation device, a pointing device such as a mouse, a digital camera, a game controller Etc.

  In addition, this invention is not limited to this embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention.

  The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

DESCRIPTION OF SYMBOLS 1 Angular velocity detection apparatus, 10 Angular velocity detection IC, 11, 16-18 External output terminal, 12-15 External input terminal, 20 Drive circuit, 22 Square wave voltage signal, 30 Detection circuit, 33
Test signal, 34 Square wave voltage signal, 36a, 37, 38a, 39a, 39c Angular velocity signal, 36b, 38b, 39b Vibration leak signal, 40 Reference power supply circuit, 50 Memory, 52, 54, 56, 58 Selection signal, 60 Failure determination circuit, 62 Failure determination signal, 70 Temperature sensor, 72 Temperature detection signal, 100 Gyro sensor element, 101a to 101b Drive vibration arm, 102 Detection vibration arm, 103 Weight part, 104a to 104b Drive base, 105a to 105b Connection Arm, 106 weight, 107 detection base, 112-113 drive electrode, 114-115 detection electrode, 116 common electrode, 210 I / V conversion circuit (current-voltage conversion circuit), 220 AC amplification circuit, 230 amplitude adjustment circuit, 310, 312 Charge amplifier, 320 Differential amplifier circuit, 330 AC amplifier circuit, 340 Phase shift circuit, 350, 352 Synchronous detection circuit, 360, 362 Integration circuit, 370 Addition / subtraction circuit, 372 Switch circuit, 374 Inverting amplifier, 376 Variable gain amplifier, 378 Adder, 380, 382 DC amplification circuit, 390, 392 Primary Temperature adjustment circuit, 394 switch circuit, 395 inverting amplifier, 396 variable gain amplifier, 397 adder, 398 primary temperature correction circuit, 500 electronic device, 600 angular velocity detection device, 700 CPU, 710 operation unit, 720 display unit, 730 ROM , 740 RAM, 750 communication unit

Claims (8)

A vibrator that generates a signal including an angular velocity component according to the magnitude of the angular velocity and a vibration leakage component of vibration based on the drive signal;
A driving unit that generates the driving signal and supplies the driving signal to the vibrator;
An angular velocity signal generator that extracts the angular velocity component from the signal generated by the vibrator and generates an angular velocity signal according to the magnitude of the angular velocity component;
A vibration leakage signal generation unit that extracts the vibration leakage component from a signal generated by the vibrator and generates a vibration leakage signal according to the magnitude of the vibration leakage component;
An angular velocity detection apparatus comprising: an addition / subtraction unit that adds or subtracts the vibration leakage signal to the angular velocity signal at a given ratio so as to correct a temperature characteristic of the angular velocity signal. In claim 1,
A first primary temperature adjustment unit that adjusts a primary component of the temperature characteristic of the angular velocity signal input to the addition / subtraction unit to approach a first value;
An angular velocity detection apparatus comprising: a second primary temperature adjustment unit that adjusts a primary component of a temperature characteristic of the vibration leakage signal input to the addition / subtraction unit to approach a second value. In claim 1,
Primary temperature adjustment for adjusting one of the primary component of the temperature characteristic of the angular velocity signal input to the adder / subtractor and the primary component of the temperature characteristic of the vibration leakage signal input to the adder / subtractor to approach the other. An angular velocity detection device including a unit. In claim 1,
An angular velocity detection device including a primary temperature correction unit that corrects a primary component of a temperature characteristic of a signal added or subtracted by the addition / subtraction unit. In any one of Claims 1 thru | or 4,
An angular velocity detection device including a terminal for outputting a signal based on the vibration leakage signal to the outside. In any one of Claims 1 thru | or 5,
An angular velocity detection device including a failure determination unit that determines whether or not there is a failure in the angular velocity detection device based on the vibration leakage signal. In any one of Claims 1 thru | or 6.
The addition / subtraction unit
An inverting amplifier for inverting the polarity of the input signal, a switch circuit for selecting whether to bypass the previous inverting amplifier, and the inverting amplifier are arranged in series to amplify or attenuate the input signal with a variably settable gain. A variable gain amplifier, wherein the inverting amplifier and the switch circuit select whether to invert the polarity of the vibration leakage signal and add it to the angular velocity signal, and to the angular velocity signal by the variable gain amplifier. An angular velocity detection device that selects a ratio of the vibration leakage signal to be added.   An electronic apparatus comprising the angular velocity detection device according to claim 1.

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