JP4356479B2 - Angular velocity sensor - Google Patents

Description

  The present invention relates to an angular velocity sensor having an abnormality diagnosis function.

  Conventionally, as this type of angular velocity sensor, there has been one as described in Patent Document 1, for example. FIG. 6 shows a conventional angular velocity sensor described in Patent Document 1. FIG. 6 is a perspective view showing a vibrator of the angular velocity sensor.

In FIG. 6, 120a and 120b are arms, 120c is a base, 120 is an oscillator made of crystal composed of arms 120a and 120b and a base 120c, 130a and 130b are arms, 130c is a base, and 130 is arms 130a and 130b and a base 130c. A tuning-fork type vibrator 110a, 110b in which the vibrator 120 and the vibrator 130 are directly joined so that the electric axis directions are in the x-axis direction and in opposite directions. A tuning fork arm, 110c is a tuning fork base, 101 is a monitor electrode, 102 is a ground electrode, 105a is a detection electrode provided on the outer surface of the tuning fork arm 110a so as to straddle the arm 120a and arm 130a, and 106a is provided on the arm 120a and arm 130a. Detection provided on the inner surface of the tuning fork arm 110a so as to straddle The pole 107a is a detection electrode provided on the inner surface of the tuning fork arm 110b so as to straddle the arms 120b and 130b, and 108a is a detection electrode provided on the outer surface of the tuning fork arm 110b so as to straddle the arms 120b and 130b. 116a is a lead-out portion for pulling out from the detection electrode 105a, 116b is a lead-out portion for pulling out from the detection electrode 108a, 116 is a lead-out electrode pad for the detection electrode to which the lead-out portion 116a and the lead-out portion 116b are connected, 141, 142, 143 , 144 are adjustment detection electrodes extending from the extraction electrode pad 116 for detection electrodes, and 113 is a drive electrode (not shown) provided to face the monitor electrode 101 provided on the main surface of the arm 130a. A drive electrode lead extended from the bottom of the base 120c to the left of the bottom The electrode pad 114 extends from a drive electrode (not shown) provided so as to face the ground electrode 102 provided on the main surface of the arm 130b, and is provided for the drive electrode provided on the right side of the lower end of the base 120c. The extraction electrode pads 145 and 146 are adjustment drive electrodes extending from the drive electrode extraction electrode pads 113 and 114, respectively. The adjustment detection electrodes 141 and 143 and the adjustment drive electrode 145 are arranged to oppose each other in a comb shape. Similarly, the adjustment detection electrodes 142 and 144 and the adjustment drive electrode 146 are arranged to oppose each other in a comb shape.
JP 2001-208546 A

  However, in the above-described conventional angular velocity sensor, a quartz material having a small piezoelectric constant is used for the tuning fork type vibrator 110, and a drive electrode and a detection part for constituting a drive part are formed on the tuning fork type vibrator 110. The detection electrodes 105a, 106a, 107a, 108a are formed, and the entire drive unit system (provided at the lower end of the base is basically provided in order to reduce unnecessary coupling capacitance components from the drive unit side to the detection unit side). The distance between the adjustment drive electrodes 145 and 146) and the entire detection unit system (including the adjustment detection electrodes 141, 142, 143, and 144 provided at the lower end of the base) is also increased.

  Therefore, when an attempt is made to produce a small angular velocity sensor, it is driven even if the patterns of the comb-like adjustment drive electrodes 145 and 146 provided on the base and the patterns of the adjustment detection electrodes 141, 142, 143 and 144 are somewhat longer. Since the coupling capacitance value between the sensor system and the detection system is inevitably small, when the detection unit system, for example, one of the wires for wiring is disconnected, a drive signal is input to the detection side electrode to detect angular velocity. The signal output from the circuit is also reduced. In this state, there has been a problem that it is impossible to accurately obtain a predetermined angular velocity signal output and a signal output due to the disconnection of the wiring wire generated in the detection unit system.

  It is an object of the present invention to provide a small angular velocity sensor that enables accurate detection of disconnection of a detection unit system.

To this end, the invention according to claim 1 of the present invention, a vibration unit which is displaced in the z-axis direction perpendicular to the x-axis direction and the x-axis, the vibration transitions leading to the vibration unit the vibration A vibrator having a support part connected to the transition part, a driving part provided with a pair of electrodes provided in the vibration part that can excite the vibration part in the x-axis direction, and the vibration part as x A drive circuit for supplying a drive signal of opposite polarity to a pair of electrodes formed on the drive unit for exciting in the axial direction, and a vibration unit for detecting deflection of the vibration unit vibrating in the z-axis direction A detection unit formed with a pair of electrodes provided and formed in the detection unit by bending in the z-axis direction based on Coriolis force when an angular velocity is applied around the y-axis orthogonal to the x-axis and the z-axis the charges of opposite polarity output from the pair of electrodes and amplification process, a predetermined range A sensing circuit having a differential amplifier for obtaining an angular velocity signal, a first pattern electrode provided on the support portion is drawn from one of a pair of electrodes formed on the drive unit, it is formed in the detection portion a pair second pattern electrode from the electrode pair provided on the withdrawn support unit respectively, between and the first pattern electrode and one of the first pattern electrode and a pair second pattern electrodes And the other of the pair of second pattern electrodes in the angular velocity sensor, the detection circuit is configured such that the angular velocity signal output from the differential amplifier exceeds a predetermined range. The angular velocity sensor is provided with an abnormal value extracting means for performing a predetermined output capable of diagnosing an abnormality, and has an effect of being able to detect an accurate disconnection of the detection unit system while being small in size.

  According to a second aspect of the present invention, the vibrator has at least two arms as vibration parts, at least one base part as a vibration transition part connecting the arms, and a support part for fixing to the end of the base part. The tuning fork vibrator is made of a non-piezoelectric material, and the vibration part is provided such that at least the upper electrode is separated from the center line on at least one main surface of at least one arm of the tuning fork vibrator. 2. The angular velocity sensor according to claim 1, wherein the sensor is a piezoelectric film, and the detection unit is a piezoelectric film provided on at least one main surface of at least one arm of the tuning fork vibrator and having electrodes on both surfaces. In addition, since it is not necessary to provide a detection unit or the like on the side surface of the tuning fork vibrator, there is an effect that it can be configured by an extremely easy manufacturing process.

  According to a third aspect of the present invention, the vibrator has at least two arms as vibration parts, at least one base part as a vibration transition part connecting the arms, and a support part for fixing to the end of the base part. The tuning fork vibrator is made of a non-piezoelectric material, and the drive unit is provided so as to be separated from the center line on at least one main surface of at least one arm of the tuning fork vibrator. A pair of piezoelectric films each having an electrode, and the detection unit is a piezoelectric film provided on at least one main surface of at least one arm of the tuning fork vibrator and having electrodes on both surfaces. 1. The angular velocity sensor according to claim 1, wherein the drive unit is separated from the center line of the arm of the tuning fork vibrator, so that vibrations with higher accuracy can be generated in the x-axis direction and the z-axis direction. I can do it Functions and effects.

According to a fourth aspect of the present invention, the abnormal value extracting means includes a lower electrode provided on the support portion, a piezoelectric film provided on the lower electrode, and a pair of the first pattern electrode on the piezoelectric film . the second pattern electrode to face the, and, is an angular velocity sensor according to claim 1 provided so as to separate, the piezoelectric film and on its very stable parts of the support portions of the tuning-fork oscillator One pattern electrode and a pair of second pattern electrodes can be provided, and an extremely large coupling capacity can be easily configured between the drive unit system and the detection unit system.

  The invention according to claim 5 is the angular velocity sensor according to claim 2 or 3, wherein the tuning fork vibrator is made of silicon, and can be made into a tuning fork vibrator having a stable elastic modulus at a very low cost. There is an effect.

According to a sixth aspect of the present invention, the piezoelectric film constituting the abnormal value extracting means is made of a PZT-based material, and the first pattern electrode and the pair of second pattern electrodes form approximately eight pairs, The opposing length of each of the first pattern electrode and the pair of second pattern electrodes is approximately 450 μm, and the opposing distance between the first pattern electrode and the pair of second pattern electrodes is approximately 5 μm. 5. The angular velocity sensor according to claim 4, wherein the output is capable of diagnosing an abnormality exceeding an angular velocity signal within a predetermined range required by the user specifications, and can secure a high manufacturing process yield. There is an operational effect.

The invention according to claim 7 is the angular velocity sensor according to claim 1 , wherein the high dielectric constant layer is made of any one of SiON, HfO _x , and HfSiO _x , and a predetermined material is used as the high dielectric constant layer. Thus, even in a smaller angular velocity sensor, there is an effect that an output capable of diagnosing an abnormality exceeding an angular velocity signal in a predetermined range required from the user specifications can be easily achieved.

  The invention according to claim 8 is the angular velocity sensor according to claim 2, wherein a high dielectric constant layer is further provided between at least the upper electrode provided in the drive unit and the upper electrode provided in the detection unit. In addition, since a high dielectric constant layer is further provided, an effect capable of easily diagnosing an abnormality exceeding an angular velocity signal in a predetermined range required by the user specifications can be easily achieved even in a smaller angular velocity sensor. .

  The invention according to claim 9 is the angular velocity sensor according to claim 3, wherein a high dielectric constant layer is further provided between at least the upper electrode provided in the drive section and the upper electrode provided in the detection section. In addition, since a high dielectric constant layer is provided, even in a smaller angular velocity sensor, it is possible to easily achieve an output capable of diagnosing an abnormality exceeding an angular velocity signal within a predetermined range required by user specifications. Play.

  In a tenth aspect of the present invention, a high dielectric constant layer is further provided at least between a lead-out portion drawn from the electrode formed in the drive portion and a lead-out portion drawn from the electrode formed in the detection portion. The angular velocity sensor according to claim 1, further comprising a high dielectric constant layer, so that an output capable of diagnosing an abnormality exceeding an angular velocity signal in a predetermined range required by a user specification even in a smaller angular velocity sensor. There is an effect that it can be easily achieved.

  A vibrator having a vibration part, a vibration transition part connected to the vibration part, and a support part connected to the vibration transition part, and the vibration part capable of exciting the vibration part in the x-axis direction. A drive unit formed with an electrode; a drive circuit for supplying a drive signal to the electrode formed on the drive unit to excite the vibration unit in the x-axis direction; and the vibration unit vibrating in the z-axis direction. A detection unit formed with an electrode provided in the vibration unit to detect the deflection of the sensor, and the detection unit formed by bending in the z-axis direction based on Coriolis force when an angular velocity is applied around the y-axis. A detection circuit having an amplifier for amplifying the charge generated in the electrode and obtaining an angular velocity signal in a predetermined range, and a first pattern drawn from the electrode formed in the drive unit and provided in the support unit Electrode and the detection unit In the angular velocity sensor provided with the second pattern electrode drawn from the formed electrode and provided on the support portion, when an abnormality occurs between the second pattern electrode and the amplifier, the detection circuit Further, the angular velocity sensor is provided with an abnormal value extraction means for obtaining an output capable of diagnosing an abnormality exceeding the angular velocity signal in the predetermined range, and can detect a proper disconnection of the detection unit system while being small.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
1 is a configuration diagram of a tuning fork vibrator of an angular velocity sensor according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of the vibrator, FIG. 3 is a cross-sectional view taken along the line BB of the vibrator, FIG. FIG. 5 is a diagram for explaining the relationship between the distance between the first pattern electrode and the second pattern electrode and the coupling capacitance, and FIG. 5 is a cross-sectional view taken along the line B-B of the same vibrator provided with a high dielectric constant layer on the surface.

  1, 2, and 3, reference numerals 10 a and 10 b denote arms of a tuning fork type vibrator 1 made of silicon, 10 c denotes a base part that forms a vibration transition part of the tuning fork type vibrator 1, and 10 d denotes a fixed base (see FIG. 1). (Not shown), a support portion of the tuning fork vibrator 1, 35 and 36 are center lines of the arms 10a and 10b, 37 and 38 are main surfaces of the arms 10a and 10b, and 11c and 12c are centers. The lower electrodes 11b and 12b provided on the main surface 37 which are separated from each other with the line 35 as a boundary, are piezoelectrically polarized in the direction perpendicular to the film surfaces made of PZT provided on the lower electrodes 11c and 12c, respectively. Films 11a and 12a are electrodes on the upper surface as drive electrodes provided on the piezoelectric films 11b and 12b, respectively; 13c and 14c are electrodes on the lower surface provided on the main surface 38 separated from the center line 36; 13 , 14b are piezoelectric films polarized in the direction perpendicular to the film surfaces made of PZT provided on the lower electrodes 13c, 14c, and 13a, 14a are drive electrodes provided on the piezoelectric films 13b, 14b, respectively. The upper electrodes 15c and 16c are provided on the main surfaces 37 and 38 of the arms 10a and 10b and along the center lines 35 and 36, respectively, and 15b and 16b are provided on the lower electrodes 15c and 16c, respectively. Piezoelectric films polarized in a direction perpendicular to the film surface made of PZT, 15a and 16a are upper electrodes as detection electrodes provided on the piezoelectric films 15b and 16b, and 17a is arms 10a and 10b are x-axis. A monitor electrode having a piezoelectric film and a lower electrode provided under the main surfaces 37 and 38 to monitor the amplitude of the tuning fork vibration in the direction, Reference numerals a, 19a, 20a, 21a, 22a, and 23a denote lead-out portions for leading out from the upper electrodes 11a, 12a, 13a, 14a, 15a, and 16a, which are each provided with a piezoelectric film and a lower electrode, and 24a is a monitor electrode 17a. A lead-out portion for pulling out from the substrate, 25 is a common ground as a lower electrode provided on the support portion 10d, and 26 is a piezoelectric film polarized in a direction perpendicular to the film surface made of PZT provided on the common ground 25 27 are lead electrode pads for supplying a positive drive signal to the upper electrodes 11a, 13a, 28 are lead electrode pads for supplying a negative drive signal to the upper electrodes 12a, 14a, and 29 is a lead-out portion 22a. The lead electrode pad connected to the lead electrode 30, the lead electrode pad 30 connected to the lead-out portion 23 a, and the lead-out electrode pads 31 a and 31 b, The comb-shaped first pattern electrode 32 provided between 20a and the extraction electrode pad 27 extends from the extraction electrode pad 29, and the comb-shaped first pattern electrode 32 is provided so as to face the first pattern electrode 31a. The second pattern electrode 33 extends from the extraction electrode pad 30 and is provided so as to face the first pattern electrode 31b. The second pattern electrode 34 has a comb-tooth shape and 34 is an extraction electrode connected to the lead-out portion 24a. It is a pad.

  As described above, the drive unit includes the upper electrode 11a, the piezoelectric film 11b and the lower electrode 11c provided on the arm 10a, the upper electrode 12a, the piezoelectric film 12b, and the lower electrode 12c. A pair of components. Similarly, a pair of structures are formed on the arm 10b. Further, the drive unit is configured to be substantially symmetrical with respect to the center line 35 on the arm 10a, and at the same time, is also configured to be approximately symmetrical between the left and right arms 10a and 10b around the symmetry axis of the tuning fork vibrator 1. Yes.

  As described above, the detection unit includes the upper electrode 15a, the piezoelectric film 15b, and the lower electrode 15c provided on the arm 10a. Similarly, the upper electrode 16a, the piezoelectric film 16b, and the lower electrode 16c are provided on the arm 10b. As described above, the detection unit is configured to be substantially symmetrical between the left and right arms 10a and 10b with the symmetry axis of the tuning fork vibrator 1 as a center.

  First, the operation of tuning fork vibration in the angular velocity sensor of the present embodiment will be briefly described.

  A drive circuit (not shown) having an AGC circuit (not shown) supplies drive signals having opposite phases to the extraction electrode pads 27 and 28. Incidentally, since a positive drive signal is supplied to the extraction electrode pad 27 and a negative drive signal is supplied to the extraction electrode pad 28, the piezoelectric film 11b contracts in the y-axis direction with the center line 35 of the arm 10a as a boundary, and The piezoelectric film 12b extends in the y-axis direction at the center line 35 of the arm 10a. This attempts to bend the arm 10a in the x-axis direction (outward). In addition, the piezoelectric film 13b contracts in the y-axis direction with the center line 36 of the arm 10b as a boundary, and the piezoelectric film 14b extends in the y-axis direction with the center line 36 of the arm 10b as a boundary. This attempts to bend the arm 10b in the x-axis direction (outward). As a result, the arms 10a and 10b cause tuning fork vibration in the xy plane. Further, the amplitude of the tuning fork vibration of the arms 10a and 10b is detected from the monitor electrode 17a and controlled through the AGC circuit so as to have a predetermined amplitude.

  Next, the operation when performing normal angular velocity detection in the angular velocity sensor of the present embodiment will be briefly described.

  When an angular velocity Ω is applied around the y axis during stable tuning fork vibration in the xy plane, the arms 10a and 10b bend in the z axis direction in opposite directions based on the Coriolis force. The deflection in the z-axis direction at this time is detected by the electrodes 15a and 16a on the upper surface. The charges detected by the electrodes 15a and 16a on the upper surface are guided to the extraction electrode pads 29 and 30, respectively. The lead electrode pads 29 and 30 are connected to, for example, an electrode pad (not shown) provided on a case (not shown) by a wire (not shown), and further, angular velocity is transmitted via these electrode pads. Each is connected to a current amplifier (not shown) in an input stage constituting a detection circuit (not shown) for detecting a signal. Incidentally, a positive charge is generated in the upper electrode 15a, and a negative charge is generated in the upper electrode 16a. After these charges having opposite polarities are input to the above-described current amplifiers, the outputs of the respective current amplifiers are input to a differential amplifier (not shown), and output as an angular velocity signal within a predetermined range after synchronous detection. .

  Next, an operation when performing an abnormality diagnosis in the angular velocity sensor of the present embodiment will be described.

  On the left side of the support portion 10d and having a length of about 450 μm in the y-axis direction, approximately eight pairs of first pattern electrodes 31a and second pattern electrodes 32 are provided so as to face each other. The distance between the first pattern electrode 31a and the second pattern electrode 32 is set to approximately 15 μm. Similarly, approximately eight pairs of the first pattern electrode 31b and the second pattern electrode 33 are provided on the right side of the support portion 10d and have a length of about 450 μm in the y-axis direction and face each other. ing. The distance between the first pattern electrode 31b and the second pattern electrode 33 is also set to about 15 μm. The shape of the portion composed of the first pattern electrode 31a and the second pattern electrode 32 and the shape of the portion composed of the first pattern electrode 31b and the second pattern electrode 33 are almost symmetrical. Therefore, the capacitance between the first pattern electrode 31a and the second pattern electrode 32 and the capacitance between the first pattern electrode 31b and the second pattern electrode 33 are substantially the same. Further, since the value of the positive drive signal superimposed on the extraction electrode pad 29 and the value of the positive drive signal superimposed on the extraction electrode pad 30 are substantially the same, they are canceled by the above-described differential amplifier. Therefore, while the angular velocity sensor is operating normally, only an angular velocity signal within a predetermined range appears from the detection circuit. The distance between the first pattern electrode 31a and the second pattern electrode 32 is as small as 15 μm, and the distance between the first pattern electrode 31b and the second pattern electrode 33 is also small. Further, since the piezoelectric film 26 is provided under the first pattern electrodes 31 a and 31 b and the second pattern electrodes 32 and 33, the gap between the first pattern electrode 31 a and the second pattern electrode 32 is provided. The capacitance value increases. Similarly, the capacitance value between the first pattern electrode 31b and the second pattern electrode 33 is also large. As shown in FIG. 4, when the distance between the first pattern electrode 31a and the second pattern electrode 32 is approximately 15 μm or less, the coupling capacitance value per opposing length exceeds approximately 45 fF that satisfies the required specifications. . The same can be said between the first pattern electrode 31 b and the second pattern electrode 33. Alternatively, the distance between the first pattern electrode 31a and the second pattern electrode 32, or the distance between the first pattern electrode 31b and the second pattern electrode 33 is preferably 15 μm or less, but is preferably as small as possible. Considering process stability, etc., it is reasonable to have a thickness of about 5 μm.

  Next, when the lead electrode pad 29 and the wire connected to the electrode pad provided in the case are disconnected, the positive drive signal superimposed on the lead electrode pad 29 canceled by the differential amplifier and the lead are extracted. The positive drive signal superimposed on the electrode pad 30 is no longer canceled. Further, as described in the above configuration, since the target capacitance value between the first pattern electrode 31b and the second pattern electrode 33 is large, a large charge is input from the extraction electrode pad 30 to the current amplifier. As a result, a large output capable of diagnosing an abnormality exceeding an angular velocity signal within a predetermined range is obtained from the differential amplifier. As a result, when the aforementioned wire breakage occurs, an output having a clear difference from the angular velocity signal output within a predetermined range is obtained, and an abnormality can be diagnosed.

  In the present embodiment, the case where the plus of the drive signal is applied to the first pattern electrodes 31a and 31b has been described. However, the comb provided as the first pattern electrode extending from the lead-out portions 19a and 21a. A configuration in which the tooth-shaped electrodes and the second pattern electrodes 32 and 33 are opposed to each other is also possible.

FIG. 5 is a cross-sectional view taken along the line B-B of the same portion of the support portion 10d shown in FIG. 3, and further, a high dielectric so as to cover at least the first pattern electrodes 31a and 31b and the second pattern electrodes 32 and 33. The rate layer 40 is provided. For the high dielectric constant layer 40, for example, a material such as SiON, HfO _x , HfSiO _x or the like can be used. However, it is not limited to this material. By providing this high dielectric constant layer 40, even a smaller angular velocity sensor can easily obtain a predetermined output capable of diagnosing an abnormality exceeding an angular velocity signal in a predetermined range required by user specifications.

  In the present embodiment, the configuration in which the further high dielectric constant layer 40 is provided on the support portion 10d has been described. However, the present invention is not limited to this. For example, the upper electrode provided in the drive portion and the detection portion are provided. It is also possible to provide between the lead-out part connected to the upper electrode constituting the driving part and the lead-out part connected to the upper electrode constituting the detection part. .

  In the present embodiment, the tuning fork vibrator is made of silicon. However, the present invention is not limited to this, and many materials made of non-piezoelectric materials can be used. Similarly, the structure of PZT has been described for the piezoelectric film, but various piezoelectric materials can be used for this.

  In the present embodiment, the tuning fork shape has been described as the vibrator. However, it is not limited to this, and various shapes can be used. For example, the shape of a cantilever beam, a rod-shaped vibrator that supports both points, or the like can be considered.

  Further, in the present embodiment, the configuration provided in the support portion of the tuning fork vibrator as the abnormal value extracting means has been described, but this is not necessarily specified.

  The angular velocity sensor of the present invention is useful as an angular velocity sensor that can detect an accurate disconnection of a detection unit system while being small in size.

Configuration diagram of tuning fork type vibrator of angular velocity sensor according to Embodiment 1 of the present invention AA sectional view of the same vibrator BB cross section of the same vibrator The figure explaining the relationship between the space | interval of a 1st pattern electrode and a 2nd pattern electrode, and a coupling capacity | capacitance Furthermore, BB cross section of the same vibrator with a high dielectric constant layer applied to the surface A perspective view showing a vibrator of a conventional angular velocity sensor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tuning fork type vibrator 10a, 10b Arm 10c Base 10d Support part 11a, 12a, 13a, 14a, 15a, 16a Upper surface electrode 11b, 12b, 13b, 14b, 15b, 16b, 26 Piezoelectric film 11c, 12c, 13c, 14c 15c, 16c Lower electrode 17a Monitor electrode 18a, 19a, 20a, 21a, 22a, 23a, 24a Deriving part 25 Common ground 27, 28, 29, 30, 34 Lead electrode pad 31a, 31b First pattern electrode 32, 33 Second pattern electrode 35, 36 Center line 37, 38 Main surface 40 High dielectric constant layer

Claims (10)

wherein a vibration portion that is displaced in the z-axis direction, the vibration transitions leading to the vibration part and a vibrator having a supporting portion connected to the vibrating transition, the vibrating section perpendicular to the x-axis direction and the x-axis and the vibration unit to the drive unit for a pair of electrodes are formed which are provided to be able to excite in the x-axis direction, it is formed in the drive unit in order to excite the vibrating portion in the x-axis direction a drive circuit for supplying a reverse polarity driving signals to a pair of electrodes, a pair of electrodes, wherein provided in the vibrating unit in order to detect the deflection of the vibrating portion which vibrates in the z-axis direction is formed and a detection unit, wherein the x-axis and the output from a pair of electrodes formed on the detecting portion by flexing the z-axis direction based on the Coriolis force when an angular velocity is applied about the y-axis perpendicular to the z-axis and amplification of the opposite polarity of charge, a predetermined range A sensing circuit having a differential amplifier for obtaining a speed signal, a first pattern electrode drawn from one of a pair of electrodes formed on the driving part provided in the support portion, the detection portion A pair of second pattern electrodes each drawn from the formed pair of electrodes and provided on the support; between the first pattern electrode and one of the pair of second pattern electrodes; and In the angular velocity sensor including the high dielectric constant layer provided between the first pattern electrode and the other of the pair of second pattern electrodes , the detection circuit is output from the differential amplifier. An angular velocity sensor provided with an abnormal value extracting means for performing a predetermined output capable of diagnosing an abnormality when the angular velocity signal exceeds the predetermined range . The vibrator is a tuning fork type vibration made of a non-piezoelectric material having at least two arms as a vibration part, at least one base part as a vibration transition part connecting the arms, and a support part for fixing to the end of the base part. The drive unit is a piezoelectric film provided such that at least the upper electrode is separated from the center line on at least one main surface of at least one arm of the tuning fork vibrator, and the detection unit The angular velocity sensor according to claim 1, wherein the angular velocity sensor is a piezoelectric film that is provided on at least one main surface of at least one arm of the tuning fork vibrator and has electrodes on both surfaces. The vibrator is a tuning fork type vibration made of a non-piezoelectric material having at least two arms as a vibration part, at least one base part as a vibration transition part connecting the arms, and a support part for fixing to the end of the base part. A pair of piezoelectric elements provided with electrodes on the upper surface and the lower surface, respectively. The drive unit is provided so as to be separated from the center line on at least one main surface of at least one arm of the tuning fork vibrator. The angular velocity sensor according to claim 1, wherein the sensor is a film, and the detection unit is a piezoelectric film provided on at least one main surface of at least one arm of the tuning fork vibrator and having electrodes on both surfaces. Abnormal value extracting means the second pattern electrode and the first pattern electrode of the pair on the piezoelectric film and the piezoelectric film provided on the lower electrode and the lower electrode provided on the support portion The angular velocity sensor according to claim 1, wherein the angular velocity sensor is provided so as to face and be separated from each other. 4. The angular velocity sensor according to claim 2, wherein the tuning fork vibrator is made of silicon. The piezoelectric film constituting the abnormal value extracting means is made of a PZT-based material, and the first pattern electrode and the second pattern electrode are almost 8 pairs opposite to each other, and the first pattern electrode and the pair of second electrodes are arranged. each of the opposing length of the pattern electrode is approximately 450 [mu] m, according to claim 4 interval is 15μm approximately 5μm to respective opposing the first pattern electrode and the pair second pattern electrodes Angular velocity sensor. The high dielectric constant layer is made of SiON, HfO. _x , HfSiO _x The angular velocity sensor according to claim 1, which is made of any one of the materials described above. The angular velocity sensor according to claim 2, wherein a high dielectric constant layer is further provided at least between an upper electrode provided in the drive unit and an upper electrode provided in the detection unit. The angular velocity sensor according to claim 3, wherein a high dielectric constant layer is further provided at least between an upper surface electrode provided in the drive section and an upper surface electrode provided in the detection section. 2. The angular velocity sensor according to claim 1, wherein a high dielectric constant layer is further provided between at least a lead-out portion drawn from the electrode formed in the drive portion and a lead-out portion drawn from the electrode formed in the detection portion.

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