JP6731235B2 - Composite switch circuit, physical quantity detection device, electronic device and mobile unit - Google Patents

Description

The present invention relates to a composite switch circuit, a physical quantity detection device, an electronic device and a moving body.

A physical quantity detection device that detects various physical quantities is known. For example, an angular velocity detection device that detects an angular velocity as a physical quantity is known, and various electronic devices and systems that are equipped with the angular velocity detection device and perform predetermined control based on the angular velocity detected by the angular velocity detection device are widely used. ing. For example, in a vehicle traveling control system for an automobile, traveling control for preventing skidding of the automobile is performed based on the angular velocity detected by the angular velocity detecting device.

As an example of such a physical quantity detection device, Patent Document 1 discloses a physical quantity measurement device provided with a synchronous detection circuit using a switch.

JP, 2009-168659, A

In the physical quantity measuring device of Patent Document 1, when a switch such as a switch used in the synchronous detection circuit is stuck in a closed state, a failure of the switch cannot be detected.

The present invention has been made in view of the above problems, and according to some aspects of the present invention, a composite switch circuit capable of detecting at least a part of a switch failure, a physical quantity detection device, and an electronic device. And a mobile body can be provided.

The present invention has been made to solve at least a part of the problems described above, and can be realized as the following aspects or application examples.

[Application example 1]
The composite switch according to this application example is
A composite switch circuit comprising an input terminal and an output terminal,
A first switch including a first terminal and a second terminal, the first terminal being connected to the input end;
A second switch including a third terminal and a fourth terminal, the third terminal being connected to the second terminal, and the fourth terminal being connected to the output end;
A fifth terminal is connected to a first node including a fifth terminal and a sixth terminal, the fifth terminal is connected to the second terminal and the third terminal, and the sixth terminal is connected to a second node. The third switch,
A first control for turning off the first switch and the second switch and turning on the third switch;
A second control for turning on the first switch and the second switch and turning off the third switch;
A control circuit for
A comparator circuit that compares the voltage of the first node and the voltage of the second node at least during the period in which the first control is performed;
Is a composite switch circuit.

According to this application example, when the first switch and the second switch are normal, the voltage between the first node and the second node is small, and at least one of the first switch and the second switch is ON and fixed. If so, the voltage between the first node and the second node increases. Therefore, it is possible to realize a composite switch circuit capable of detecting at least a part of a switch failure.

[Application example 2]
The composite switch circuit described above,
The control circuit is
A voltage that changes periodically may be applied to the second node.

According to this application example, even when the voltage between the second node and the input terminal or the output terminal is accidentally reduced when at least one of the first switch and the second switch is fixed to be ON. As the voltage of the second node changes, the voltage between the first node and the second node increases eventually. Therefore, it is possible to realize a composite switch circuit capable of accurately detecting at least a part of a switch failure.

[Application example 3]
The composite switch circuit described above,
The control circuit is
A voltage that periodically changes within the period in which the first control is performed may be applied to the second node.

According to this application example, even when the voltage between the second node and the input terminal or the output terminal is accidentally reduced when at least one of the first switch and the second switch is fixed to be ON. , The voltage between the first node and the second node increases as the voltage of the second node changes during the period of the first control, and eventually increases during the period of the first control. .. Therefore, it is possible to realize a composite switch circuit capable of accurately detecting at least a part of a switch failure.

[Application example 4]
The composite switch according to this application example is
A composite switch circuit comprising a first input end, a second input end, a first output end, and a second output end,
A first switch including a first terminal and a second terminal, the first terminal being connected to the first input end;
A second switch including a third terminal and a fourth terminal, the third terminal being connected to the second terminal, and the fourth terminal being connected to the first output end;
A fifth terminal is connected to a first node including a fifth terminal and a sixth terminal, the fifth terminal is connected to the second terminal and the third terminal, and the sixth terminal is connected to a second node. The third switch,
A fourth switch including a seventh terminal and an eighth terminal, the seventh terminal being connected to the second input end;
A fifth switch including a ninth terminal and a tenth terminal, wherein the ninth terminal is connected to the eighth terminal, and the tenth terminal is connected to the second output end;
An eleventh terminal and a twelfth terminal are included, the eleventh terminal is connected to a third node to which the eighth terminal and the ninth terminal are connected, and the twelfth terminal is connected to a fourth node. The sixth switch,
A first control for turning off the first switch and the second switch and turning on the third switch;
A second control for turning on the first switch and the second switch and turning off the third switch;
A third control for turning off the fourth switch and the fifth switch and turning on the sixth switch;
A fourth control for turning on the fourth switch and the fifth switch and turning off the sixth switch;
A control circuit for
A comparator circuit that compares the voltage of the first node with the voltage of the third node at least during a period in which the first control and the third control are performed;
Is a composite switch circuit.

According to this application example, when the first switch and the second switch are normal, the voltage between the first node and the second node is small, and at least one of the first switch and the second switch is ON and fixed. If so, the voltage between the first node and the second node increases. Further, when the fourth switch and the fifth switch are normal, the voltage between the third node and the fourth node is small, and when at least one of the fourth switch and the fifth switch is ON and fixed. , The voltage between the third node and the fourth node increases. As a result, when any of the first switch, the second switch, the fourth switch, and the fifth switch is ON and stuck, the voltage between the first node and the third node increases. Therefore, it is possible to realize a composite switch circuit capable of detecting at least a part of a switch failure.

[Application example 5]
The physical quantity detection device according to this application example,
The physical quantity detection device includes a synchronous detection circuit including any one of the above-described composite switch circuits.

According to this application example, since the composite switch circuit that can detect at least a part of the switch failure is included, it is possible to realize a physical quantity detection device suitable for highly reliable applications.

[Application example 6]
In the above physical quantity detection device,
Register,
An abnormality determination circuit, wherein the comparison circuit determines that an abnormality has occurred based on the result of the comparison, and writes error information to the register when the result of the determination is abnormal.
May be provided.

According to this application example, the error information can be easily used in another circuit block or device.

[Application example 7]
A physical quantity detection device as described above,
The comparison circuit may include an abnormality determination circuit that determines that an abnormality has occurred based on the result of the comparison and outputs an error information signal to the outside when the result of the determination is abnormal.

According to this application example, the error signal can be easily used in another circuit block or device.

[Application example 6]
The electronic device according to this application example,
An electronic device including any of the above-described composite switch circuits.

According to this application example, since the composite switch circuit that can detect at least a part of the failure of the switch is included, it is possible to realize an electronic device suitable for a highly reliable application.

[Application example 7]
The moving body according to this application example is
A mobile body including the composite switch circuit according to any one of the above.

According to this application example, since the composite switch circuit capable of detecting at least a part of the failure of the switch is included, it is possible to realize a mobile body suitable for a highly reliable application.

It is a circuit diagram of a composite switch circuit of the first embodiment. It is a circuit diagram of a composite switch circuit of the second embodiment. It is a circuit diagram of the compound switch circuit of 3rd Embodiment. It is a circuit diagram of a composite switch circuit of a fourth embodiment. It is a figure which shows the structural example of the angular velocity detection apparatus of 1st Embodiment. It is a top view of the resonator element of a gyro sensor element. It is a figure for demonstrating operation|movement of a gyro sensor element. It is a figure for demonstrating operation|movement of a gyro sensor element. It is a figure which shows the structural example of the angular velocity detection apparatus of 2nd Embodiment. It is a functional block diagram of a physical quantity detection device of a 3rd embodiment. It is a functional block diagram of the electronic device which concerns on this embodiment. It is a figure which shows an example of the external appearance of the smart phone which is an example of an electronic device. It is a figure (top view) which shows an example of the mobile which concerns on this embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The drawings used are for convenience of description. It should be noted that the embodiments described below do not unduly limit the content of the invention described in the claims. Moreover, not all of the configurations described below are essential configuration requirements of the invention.

1. Composite switch circuit 1-1. First Embodiment FIG. 1 is a circuit diagram of a composite switch circuit 90 of the first embodiment.

The composite switch circuit 90 of this embodiment has an input end IN and an output end OUT. In the example shown in FIG. 1, the composite switch circuit 90 includes a switch unit 900 including a first switch SW1, a second switch SW2, and a third switch SW3, a control circuit 920, and a comparison circuit 930. ing.

The first switch SW1 includes a first terminal 901 and a second terminal 902, and the first terminal 901 is connected to the input terminal IN.

The second switch SW2 includes a third terminal 903 and a fourth terminal 904, the third terminal 903 is connected to the second terminal 902, and the fourth terminal 904 is connected to the output terminal OUT.

The third switch SW3 includes a fifth terminal 905 and a sixth terminal 906, the fifth terminal 905 is connected to a first node N1 to which the second terminal 902 and the third terminal 903 are connected, and a sixth node
The terminal 906 is connected to the second node N2. In the example shown in FIG. 1, the second node N2 is connected to the ground potential, but not limited to this, another fixed potential may be used.

The control circuit 920 switches the first switch SW1 and the second switch SW2 to OFF and the first control to switch the third switch SW3 to ON, and switches the first switch SW1 and the second switch SW2 to ON, The second control for switching the switch SW3 to OFF is performed. The control circuit 920 can turn off between the input end IN and the output end OUT by performing the first control, and can turn on between the input end IN and the output end OUT by performing the second control. ..

In the example shown in FIG. 1, the control circuit 920 controls the first switch SW1 and the second switch SW2 by the control signal S1, and controls the third switch SW3 by the control signal S2. Further, in the example shown in FIG. 1, the control circuit 920 receives the input of the reference clock signal and compares it with the reference voltage to generate a control signal S1, and a comparator 921 that inverts the control signal S1 and outputs the control signal S2. And an inverter 922 that generates

The comparison circuit 930 compares the voltage of the first node N1 and the voltage of the second node N2 at least during the period when the first control is performed, and outputs the comparison signal 93. The comparison circuit 930 outputs a high level when the voltage between the first node N1 and the second node N2 is equal to or higher than the reference value, and outputs a low level when the voltage is lower than the reference value.

According to the present embodiment, when the first switch SW1 and the second switch SW2 are normal, the voltage between the first node N1 and the second node N2 is small, and the voltage of the first switch SW1 and the second switch SW2 is small. When at least one of them is ON and fixed, the voltage between the first node N1 and the second node N2 becomes large. Therefore, the composite switch circuit 90 capable of detecting at least a part of the failure of the first switch SW1 and the second switch SW2 can be realized.

1-2. Second Embodiment FIG. 2 is a circuit diagram of a composite switch circuit 90a according to the second embodiment. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The composite switch circuit 90a includes a switch unit 900, a control circuit 920a, and a comparison circuit 930.

The control circuit 920a applies a voltage that changes periodically to the second node N2. In the example shown in FIG. 2, the control circuit 920a outputs the control signal S3, which is a voltage signal that periodically changes, to the second node N2. Further, in the example shown in FIG. 2, the control circuit 920a includes a frequency dividing circuit 923 that divides the control signal S1 by two. The frequency division ratio of the frequency divider circuit 923 is not particularly limited.

According to this embodiment, when at least one of the first switch SW1 and the second switch SW2 is ON and fixed, the voltage between the second node N and the input terminal IN or the output terminal OUT is accidentally changed. Even if it becomes smaller, the voltage between the first node N1 and the second node N2 will eventually increase as the voltage at the second node N2 changes. Therefore, it is possible to realize the composite switch circuit 90a that can accurately detect at least a part of the failure of the first switch SW1 and the second switch SW2.

1-3. Third Embodiment FIG. 3 is a circuit diagram of a composite switch circuit 90b according to a third embodiment. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The composite switch circuit 90b includes a switch unit 900, a control circuit 920b, and a comparison circuit 930.

The control circuit 920b applies to the second node N2 a voltage that periodically changes during the period in which the first control is performed. In the example shown in FIG. 3, the control circuit 920b outputs, to the second node N2, the control signal S4, which is a voltage signal that periodically changes during the period in which the first control is performed. Further, in the example shown in FIG. 3, the control circuit 920b includes a phase shift circuit 924 that delays the phase of the control signal S1 by 90 degrees.

According to the present embodiment, when at least one of the first switch SW1 and the second switch SW2 is ON and fixed, the voltage between the second node N2 and the input terminal IN or the output terminal OUT is accidentally changed. Even when the voltage becomes small, the voltage between the first node N1 and the second node N2 is controlled by the first control because the voltage of the second node N2 changes within the period in which the first control is performed. Will eventually grow during the period. Therefore, it is possible to realize the composite switch circuit 90b that can accurately detect at least a part of the failure of the first switch SW1 and the second switch SW2.

1-4. Fourth Embodiment FIG. 4 is a circuit diagram of a composite switch circuit 90c of the fourth embodiment.

The composite switch circuit 90c of the present embodiment is a composite switch circuit 90c that includes a first input end IN1, a second input end IN2, a first output end OUT1, and a second output end OUT2. In the example shown in FIG. 4, the composite switch circuit 90c includes a switch unit 900 including a first switch SW1, a second switch SW2, and a third switch SW3, a fourth switch SW4, a fifth switch SW5, and a sixth switch SW6. The switch unit 900a includes a control circuit 920c, and a comparison circuit 930a.

The first switch SW1 includes a first terminal 901 and a second terminal 902, and the first terminal 901 is connected to the first input terminal IN1.

The second switch SW2 includes a third terminal 903 and a fourth terminal 904, the third terminal 903 is connected to the second terminal 902, and the fourth terminal 904 is connected to the first output end OUT1.

The third switch SW3 includes a fifth terminal 905 and a sixth terminal 906, the fifth terminal 905 is connected to a first node N1 to which the second terminal 902 and the third terminal 903 are connected, and a sixth node The terminal 906 is connected to the second node N2.

The fourth switch SW4 includes a seventh terminal 907 and an eighth terminal 908, and the seventh terminal 907 is connected to the second input end IN2.

The fifth switch SW5 includes a ninth terminal 909 and a tenth terminal 910, the ninth terminal 909 is connected to the eighth terminal 908, and the tenth terminal 910 is connected to the second output end OUT2.

The sixth switch SW6 includes an eleventh terminal 911 and a twelfth terminal 912, the eleventh terminal 911 is connected to the third node N3 to which the eighth terminal 908 and the ninth terminal 909 are connected, and the twelfth terminal The terminal 912 is connected to the fourth node N4.

The control circuit 920c switches the first switch SW1 and the second switch SW2 to OFF, and the first control for switching the third switch SW3 to ON, and switches the first switch SW1 and the second switch SW2 to ON. Second control for switching the switch SW3 to OFF, third control for switching the fourth switch SW4 and the fifth switch SW5 to OFF, and switching the sixth switch SW6 to ON, and the fourth switch SW4 and the fifth switch The fourth control for switching SW5 to ON and switching the sixth switch SW6 to OFF is performed. The control circuit 920 can turn off between the first input end IN1 and the first output end OUT1 by performing the first control, and by performing the second control, the first input end IN1 and the first output end. You can turn it on between OUT1 and OUT1. Further, the control circuit 920 can turn off between the second input end IN2 and the second output end OUT2 by performing the third control, and can perform the fourth control by performing the fourth control. It is possible to turn on the output terminal OUT2.

In the example shown in FIG. 4, the control circuit 920c controls the first switch SW1 and the second switch SW2 by the control signal S1, the third switch SW3 by the control signal S2, and the fourth switch SW4 by the control signal S5. The fifth switch SW5 is controlled, and the sixth switch SW6 is controlled by the control signal S6. In the example shown in FIG. 4, the control circuit 920c receives the input of the reference clock signal and compares it with the reference voltage to generate the control signal S1, and the control circuit S1 inverts the control signal S1. A phase shift circuit 925 that delays the phase of the control signal S1 by 90 degrees to generate the control signal S5, and an inverter 926 that inverts the control signal S5 to generate the control signal S6. Has been done.

The comparison circuit 930a compares the voltage of the first node N1 with the voltage of the third node N3 at least during the period in which the first control and the third control are performed, and outputs the comparison signal 93a. The comparison circuit 930a outputs a high level when the voltage between the first node N1 and the third node N3 is equal to or higher than the reference value, and outputs a low level when the voltage is lower than the reference value.

According to the present embodiment, when the first switch SW1 and the second switch SW2 are normal, the voltage between the first node N1 and the second node N2 is small, and the voltage of the first switch SW1 and the second switch SW2 is small. When at least one of them is ON and fixed, the voltage between the first node N1 and the second node N2 becomes large. When the fourth switch SW4 and the fifth switch SW5 are normal, the voltage between the third node N3 and the fourth node N4 is small, and at least one of the fourth switch SW4 and the fifth switch SW5 is ON. When fixed, the voltage between the third node N3 and the fourth node N4 increases. As a result, when any one of the first switch SW1, the second switch SW2, the fourth switch SW4, and the fifth switch SW5 is ON and fixed, the voltage between the first node N1 and the third node N3. Will grow. Therefore, it is possible to realize the composite switch circuit 90c that can detect at least a part of the failure of the first switch SW1, the second switch SW2, the fourth switch SW4, and the fifth switch SW5.

2. Physical quantity detection device 2-1. First Embodiment Hereinafter, a physical quantity detection device (angular velocity detection device) that detects an angular velocity as a physical amount will be described as an example, but the present invention detects any of various physical amounts such as angular velocity, acceleration, geomagnetism, and pressure. It is applicable to a device that can.

FIG. 5 is a diagram showing a configuration example of the angular velocity detection device 1 of the first embodiment. The angular velocity detection device 1 includes a synchronous detection circuit including a composite switch circuit 90.

The angular velocity detection device 1 of the first embodiment is configured to include a gyro sensor element 100 and an angular velocity detection circuit 4 (an example of a physical quantity detection circuit).

The gyro sensor element 100 (an example of a vibrator) is configured by sealing a vibrating piece on which drive electrodes and detection electrodes are arranged in a package (not shown). In general, the airtightness inside the package is ensured in order to make the impedance of the resonator element as small as possible to improve 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). , Or a piezoelectric thin film 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. It may be.

In the present embodiment, the gyro sensor element 100 is composed of a so-called double T-type vibrating piece having two T-type drive vibrating arms. However, the vibrating piece of the gyro sensor element 100 may be, for example, a tuning fork type, or may be a vibrating piece type having a shape such as a triangular prism, a quadrangular prism, or a column.

FIG. 6 is a plan view of the resonator element of the gyro sensor element 100 of this embodiment.

The gyro sensor element 100 of this embodiment has a double T-shaped vibrating piece formed of a Z-cut crystal substrate. The vibrating reed made of quartz has an extremely small fluctuation in the resonance frequency with respect to a temperature change, and therefore has an advantage that the accuracy of detecting the angular velocity can be improved. The X axis, Y axis, and Z axis in FIG. 6 indicate the axes of the crystal.

As shown in FIG. 6, in the vibrating piece of the gyro sensor element 100, driving vibrating arms 101a and 101b extend from two driving bases 104a and 104b in the +Y axis direction and the −Y axis direction, respectively. The drive electrodes 112 and 113 are formed on the side surfaces and the upper surface of the drive vibrating arm 101a, respectively, and the drive electrodes 113 and 112 are formed on the side surfaces and the upper surface of the drive vibrating 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 circuit 4 shown in FIG. 1, respectively.

The drive bases 104a and 104b are connected to the 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 vibration arm 102, and a common electrode 116 is formed on the side surface of the detection vibration 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 circuit 4 shown in FIG. 1, respectively. Further, the common electrode 116 is grounded.

When an AC voltage is applied as a drive signal between the drive electrodes 112 and 113 of the drive vibrating arms 101a and 101b, as shown in FIG. 7, the drive vibrating arms 101a and 101b are driven by the inverse piezoelectric effect as shown by arrow B. In addition, the tip ends of the two drive vibrating arms 101a and 101b perform bending vibration (excitation vibration) in which they approach and leave each other repeatedly.

In this state, when an angular velocity about the Z axis as a rotation axis is applied to the vibrating reed of the gyro sensor element 100, the drive vibrating arms 101a and 101b cause Coriolis motion in a direction perpendicular to both the bending vibration direction of arrow B and the Z axis. Get the power of. As a result, as shown in FIG. 8, the connecting arms 105a and 105b vibrate as indicated by arrow C. Then, the detection vibrating arm 102 interlocks with the vibration (arrow C) of the connecting arms 105a and 105b to perform bending vibration as indicated by arrow D. The flexural vibration of the detection vibrating arm 102 and the flexural vibration (excitation vibration) of the drive vibrating arms 101a and 101b due to the Coriolis force are out of phase by 90°.

By the way, if the magnitude of the vibration energy or the magnitude of the vibration amplitude when the drive vibrating arms 101a and 101b perform flexural vibration (excited vibration) is equal between the two drive vibrating arms 101a and 101b, the drive vibrating arm 101a, The vibration energy of 101b is balanced, and the detection vibration arm 102 does not flexurally vibrate when the angular velocity is not applied to the gyro sensor element 100. However, when the balance of the vibration energy of the two drive vibrating arms 101a and 101b is lost, the bending vibration is generated in the detection vibrating arm 102 even when the angular velocity is not applied to the gyro sensor element 100. This bending vibration is called leaking vibration, and is bending vibration indicated by arrow D similarly to the vibration based on Coriolis force, but has the same phase as the drive signal.

Then, due to the piezoelectric effect, AC charges based on these bending vibrations are generated in the detection electrodes 114 and 115 of the detection vibration arm 102. 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 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 tips 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, it is possible to increase the Coriolis force and obtain a desired resonance frequency with a relatively short vibrating arm. Similarly, a weight portion 106 having a width wider than that of 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, it is possible to increase the AC charges generated in the detection electrodes 114 and 115.

As described above, the gyro sensor element 100 detects the alternating-current charge (detection signal) based on the Coriolis force and the alternating-current charge (leak signal) based on the leakage vibration of the excitation vibration with the Z axis as the detection axis. Output via.

Returning to FIG. 1, the angular velocity detection circuit 4 includes a drive circuit 20 and a detection circuit 30.

The drive circuit 20 generates a drive signal 21 for exciting and vibrating the gyro sensor element 100, and supplies the drive signal 21 to the drive electrode 112 of the gyro sensor element 100 via the external output terminal 11. Further, the drive circuit 20 is driven so that the drive signal 22 generated in the drive electrode 113 by the excitation vibration of the gyro sensor element 100 is input through the external input terminal 12 and the amplitude of the drive signal 22 is kept constant. The amplitude level of the signal 21 is feedback controlled.

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

The drive current flowing 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 amplification circuit 220 and the amplitude adjustment circuit 230. The AC amplifier circuit 220 amplifies the input AC voltage signal, clips it at a predetermined voltage value, and outputs a square wave voltage signal 23. The amplitude adjustment circuit 230 changes the amplitude of the square-wave voltage signal 23 according to 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 23 is supplied as the drive signal 21 to the drive electrode 112 of the vibrating piece of the gyro sensor element 100 via the external output terminal 11. As described above, the gyro sensor element 100 continuously excites a 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 velocity. Therefore, the vibration velocity that is the source of the Coriolis force is constant, and the sensitivity can be made more stable.

The detection circuit 30 receives AC charges (detection currents) 31 and 32 generated in the detection electrodes 114 and 115 of the gyro sensor element 100 via the external input terminals 13 and 14, respectively, and receives the AC charges (detection current). The desired component contained in is extracted.

The detection circuit 30 includes charge amplifiers 310 and 312, a differential amplification circuit 320, an AC amplification circuit 330, a composite switch circuit 90, an integration circuit 360, and a DC amplification circuit 370.

AC charges including a detection signal and a leakage signal are input to the charge amplifier 310 from the detection electrode 114 of the resonator element of the gyro sensor element 100 via the external input terminal 13.

Similarly, AC charge including a detection signal and a leakage signal is input to the charge amplifier 312 from the detection electrode 115 of the resonator element 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 with the reference voltage Vref as a reference. Note that Vref is generated by a reference power supply circuit (not shown) based on an external power supply input from the outside.

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 eliminating the in-phase component and additively amplifying the anti-phase component.

The AC amplifier circuit 330 amplifies the output signal of the differential amplifier circuit 320. The output signal of the AC amplifier circuit 330 is input to the input terminal IN of the composite switch circuit 90. The output signal of the AC amplifier circuit 330 includes a detection signal according to the magnitude of the physical quantity (angular velocity) and a vibration leakage signal based on the drive signal.

The composite switch circuit 90 synchronously detects the detection signal based on the control signal S1 generated based on the square wave voltage signal 23 with respect to the signal input to the input terminal IN. It outputs to the integration circuit 350 via the output terminal OUT. That is, the composite switch circuit 90 functions as a synchronous detection circuit.

The output signal from the output terminal OUT of the composite switch circuit 90 is smoothed into a DC voltage signal by the integration circuit 360 and input to the DC amplification circuit 370 as the angular velocity signal 36a.

The DC amplifier circuit 380 amplifies or attenuates the angular velocity signal 36a to a desired level, and outputs it as an angular velocity signal 37a to the outside via the external output terminal 16. An external device (not shown) can obtain the angular velocity information by monitoring the angular velocity signal 37a.

The abnormality determination circuit 40 determines the presence or absence of abnormality based on the comparison signal 93 from the comparison circuit 930 of the composite switch circuit 90, and outputs information regarding the determination result to the external output terminal 19 as an error information signal 41. In the present embodiment, the abnormality determination circuit 40 determines that an abnormality has occurred when the comparison circuit 930 outputs a high level as the comparison signal 93.

In the present embodiment, when the angular velocity detection device 1 (physical quantity detection device) is determined to be abnormal, the abnormality determination circuit 40 outputs an error information signal 41 indicating that the determination result is abnormal to the external output terminal 19. You may. This allows the error information signal to be easily used in other circuit blocks or devices.

In the present embodiment, the angular velocity signal processing circuit 4 includes a register 43. The register 43 is configured to be able to output the stored information as a digital signal 44 to the outside through the external terminal 18. Further, the abnormality determination circuit 40 may write error information in the register 43 when the angular velocity detection device 1 (physical quantity detection device) determines that it is abnormal based on the comparison signal 93. In the example shown in FIG. 1, the abnormality determination circuit 40 writes the error information in the register 43 by outputting the error information signal 42 to the register 43. By having the register 43, the error information can be easily used in other circuit blocks or devices.

According to the present embodiment, since the composite switch circuit 90 capable of detecting at least a part of the switch failure is included, the angular velocity detection device 1 (physical quantity detection device) suitable for highly reliable applications can be realized.

It should be noted that similar effects can be obtained when the composite switch circuit 90a or the composite switch circuit 90b is used instead of the composite switch circuit 90.

2-2. Second Embodiment FIG. 9 is a diagram showing a configuration example of an angular velocity detection device 1a according to the second embodiment. The angular velocity detection device 1a includes a synchronous detection circuit including a composite switch circuit 90c. The same components as those of the angular velocity detector 1 of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The composite switch circuit 90a synchronously detects the detection signal based on the control signal S1 generated based on the square wave voltage signal 23 with respect to the signal input to the first input terminal IN1. The signal is output to the integrating circuit 360 via the first output terminal OUT1. The composite switch circuit 90a synchronously detects the leak signal based on the control signal S5 obtained by delaying the phase of the control signal S1 by 90 degrees with respect to the signal input to the second input terminal IN2. The signal is output to the integrating circuit 362 via the second output terminal OUT2. That is, the composite switch circuit 90c functions as a synchronous detection circuit.

The output signal from the first output end OUT1 of the composite switch circuit 90c is smoothed into a DC voltage signal by the integrating circuit 360 and input to the DC amplifier circuit 370 as the angular velocity signal 36a.

The output signal from the second output terminal OUT2 of the composite switch circuit 90c is smoothed into a DC voltage signal by the integration circuit 362, and is input to the DC amplification circuit 372 as the leakage signal 36b.

The DC amplifier circuit 380 amplifies or attenuates the angular velocity signal 36a to a desired level, and outputs it as an angular velocity signal 37a to the outside via the external output terminal 16. An external device (not shown) can obtain the angular velocity information by monitoring the angular velocity signal 37a.

The DC amplifier circuit 382 amplifies or attenuates the leak signal 36b to a desired level and outputs the leak signal 37b to the outside via the external output terminal 17. Then, 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 leak signal 37b.

The abnormality determination circuit 40a determines the presence or absence of abnormality based on the comparison signal 93a from the comparison circuit 930a of the composite switch circuit 90c, and outputs information regarding the determination result to the external output terminal 19 as an error information signal 41a. In this embodiment, the abnormality determination circuit 40a determines that an abnormality has occurred when the comparison circuit 930a outputs a high level.

Further, the abnormality determination circuit 40a may write error information in the register 43 when the angular velocity detection device 1a (physical quantity detection device) determines that it is abnormal based on the comparison signal 93a. In the example shown in FIG. 9, the abnormality determination circuit 40a writes the error information in the register 43 by outputting the error information signal 42 to the register 43. By having the register 43, the error information can be easily used in other circuit blocks or devices.

According to this embodiment, since the composite switch circuit 90c capable of detecting at least a part of the switch failure is included, the angular velocity detecting device 1 (physical quantity detecting device) suitable for highly reliable use can be realized.

2-3. Third Embodiment FIG. 10 is a functional block diagram of a physical quantity detection device 1000 according to the third embodiment. The same components as those of the physical quantity detection device (angular velocity detection device 1) of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The physical quantity detection device 1000 detects an angular velocity in the uniaxial direction and an acceleration in the biaxial direction as physical quantities. The physical quantity detection device 1000 includes a gyro sensor element 100 and an angular velocity detection circuit 4 as a configuration for detecting an angular velocity. The physical quantity detection device 1000 includes a detection element 400x, a detection element 400y, and an acceleration detection circuit 5 as a configuration for detecting acceleration. In addition, the physical quantity detection device 1000 includes a temperature sensor 3 in order to perform correction based on temperature.

The physical quantity detection device 1000 of this embodiment further includes a selection circuit 6, an ADC (Analog-to-digital converter) 7, a digital processing circuit 8, an interface circuit 9, and a failure diagnosis circuit 10.

In the present embodiment, the configuration excluding the gyro sensor element 100, the detection element 400x, and the detection element 400y is configured as a physical quantity detection circuit (integrated circuit device) 2. Note that the physical quantity detection device 1000 of the present embodiment may be configured such that some of these components (elements) are omitted or new components (elements) are added.

The temperature sensor 3 outputs a temperature signal 408 according to the temperature to the selection circuit 6.

The angular velocity detection circuit 4 outputs an angular velocity signal 37a according to the angular velocity to the selection circuit 6. Further, the angular velocity detection circuit 4 outputs the error information signal 41 to the failure diagnosis circuit 10.

The detection element 400x and the detection element 400y are configured by a capacitance type acceleration detection element. The detection element 400x receives the carrier wave signal 401 from the acceleration detection circuit 5, and differentially outputs the detection signal 402 and the detection signal 403 corresponding to the detected acceleration to the acceleration detection circuit 5. The detection element 400y receives the carrier wave signal 401 from the acceleration detection circuit 5, and differentially outputs the detection signal 404 and the detection signal 405 corresponding to the detected acceleration to the acceleration detection circuit 5.

The acceleration detection circuit 5 outputs an acceleration signal 406 corresponding to the acceleration to the selection circuit 6 based on the detection signals 402 to 405. Further, the acceleration detection circuit 5 outputs information regarding an abnormality occurring in the acceleration detection circuit 5 to the failure diagnosis circuit 10 as an error information signal 407.

The selection circuit 6 sequentially selects one of the input signals and outputs it as a signal 409 to the ADC 7.

The ADC 7 converts the input signal into a digital signal and outputs it as a signal 410 to the digital processing circuit 8.

The digital processing circuit 8 performs various digital processes on the input signal and outputs it as a signal 411 to the interface circuit 9. As the digital processing, for example, filter processing or processing for correcting temperature characteristics may be performed.

The failure diagnosis circuit 10 determines whether or not an abnormality has occurred in at least one of the angular velocity detection circuit 4, the acceleration detection circuit 5, the gyro sensor element 100, the detection element 400x, and the detection element 400y based on the input signal. The determination result is output to the interface circuit 9 as a signal 412.

The interface circuit 9 converts the input signal into a predetermined communication format and outputs it as a signal 413 to the outside.

The physical quantity detection device 1000 according to the third embodiment also exhibits the same effect for the same reason as in the first embodiment. Further, even when the angular velocity detection circuit 4a is used instead of the angular velocity detection circuit 4, the same effect is obtained.

3. Electronic Device FIG. 11 is a functional block diagram of the electronic device 500 according to the present embodiment. The same components as those in the above-described embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

The electronic device 500 according to the present embodiment is an electronic device 500 including the angular velocity detection device 1 (physical amount detection device) including the angular velocity detection circuit 4 (physical amount detection circuit) including the composite switch circuit 90. In the example illustrated in FIG. 11, the electronic device 500 includes an angular velocity detection device 1, a CPU (Central Processing Unit) 520, an operation unit 530, a ROM (Read Only Memory) 540, a RAM (Random Access Memory) 550, a communication unit 560, The display unit 570 and the sound output unit 580 are included. Note that the electronic device 500 according to the present embodiment may omit or change some of the components (sections) shown in FIG. 11, or may have a configuration in which other components are added.

The CPU 520 performs various calculation processes and control processes using clock pulses output from a clock signal generation circuit (not shown) in accordance with programs stored in the ROM 540 and the like. Specifically, the CPU 520 performs various processes according to operation signals from the operation unit 530, processes for controlling the communication unit 560 to perform data communication with the outside, and various kinds of information for displaying various information on the display unit 570. A process of transmitting a display signal, a process of causing the sound output unit 580 to output various sounds, and the like are performed.

The operation unit 530 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 520.

The ROM 540 stores programs and data for the CPU 520 to perform various calculation processes and control processes.

The RAM 550 is used as a work area of the CPU 520, and temporarily stores programs and data read from the ROM 540, data input from the operation unit 530, calculation results executed by the CPU 520 according to various programs, and the like.

The communication unit 560 performs various controls for establishing data communication between the CPU 520 and an external device.

The display unit 570 is a display device including an LCD (Liquid Crystal Display), an electrophoretic display, and the like, and displays various information based on a display signal input from the CPU 520.

The sound output unit 580 is a device that outputs sounds such as a speaker.

When the CPU 520 receives from the angular velocity detecting device 1 an error signal indicating that the angular velocity detecting device 1 has some abnormality, the CPU 520 specifies the location where the abnormality has occurred in order to specify the angular velocity signal processing of the above-described first embodiment. The angular velocity signal processing circuit 4a of the circuit 4 or the second embodiment sends a command to the angular velocity detection device 1 to instruct the abnormality determination circuit 40 to determine whether or not an abnormality has occurred in at least a part of the switch. You may.

Since the electronic device 500 according to the present embodiment includes the composite switch circuit 90 capable of detecting at least a part of the switch failure, the electronic device 500 suitable for highly reliable applications can be realized. Even when the composite switch circuit 90, 90a, 90b, or 90c is used instead of the composite switch circuit 90, the same effect is obtained.

Various electronic devices can be considered as the electronic device 500. For example, personal computers (for example, mobile personal computers, laptop personal computers, tablet personal computers), mobile terminals such as mobile phones, digital cameras, inkjet discharge devices (for example, inkjet printers), routers, switches, etc. Storage area network equipment, local area network equipment, mobile terminal base station equipment, televisions, video cameras, video recorders, car navigation equipment, pagers, electronic organizers (including communication functions), electronic dictionaries, calculators, electronic games Devices, game controllers, word processors, workstations, videophones, crime prevention TV monitors, electronic binoculars, POS (point of sale) terminals, medical devices (eg electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiogram measuring devices, ultrasonic diagnostics) Device, electronic endoscope), fish finder, various measuring instruments, instruments (for example, instruments for vehicles, aircrafts, ships), electricity meters, flight simulators, head mounted displays, motion traces, motion tracking, motion controllers, PDR (pedestrian position and orientation measurement) and the like can be mentioned.

FIG. 12 is a diagram illustrating an example of the appearance of a smartphone that is an example of electronic device 500. The smartphone that is the electronic device 500 includes a button as the operation unit 530 and an LCD as the display unit 570. Since the smartphone, which is the electronic device 500, includes the composite switch circuit 90 capable of detecting at least a part of the switch failure, the electronic device 500 suitable for highly reliable applications can be realized.

4. Moving Body FIG. 13 is a diagram (top view) showing an example of the moving body 600 according to the present embodiment. The same components as those in the above-described embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

The moving body 600 according to the present embodiment is a moving body 400 including a physical quantity detection device 1000 including an angular velocity detection circuit 4 (physical quantity detection circuit) including a composite switch circuit 90. In addition, in the example shown in FIG. 13, the moving body 600 includes a controller 620, a controller 630, a controller 640, a battery 650, and a backup battery 660 that perform various controls such as an engine system, a brake system, and a keyless entry system. It is configured. Note that the moving body 600 according to the present embodiment may have a configuration in which some of the components (respective parts) shown in FIG. 13 are omitted or changed, or other components may be added.

Since the mobile unit 600 according to the present embodiment includes the composite switch circuit 90 capable of detecting at least a part of the switch failure, the mobile unit 600 having high reliability can be realized. Even when the composite switch circuit 90, 90a, 90b, or 90c is used instead of the composite switch circuit 90, the same effect is obtained.

Various moving bodies can be considered as such moving body 600, and examples thereof include automobiles (including electric vehicles), aircraft such as jet planes and helicopters, ships, rockets, artificial satellites, and the like.

The present invention is not limited to this embodiment, and various modifications can be made within the scope of the gist of the present invention.

The above-described embodiments and modifications are examples, and the present invention is not limited to these. For example, each embodiment and each modification can be combined as appropriate.

The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations having the same function, method, and result, or configurations having the same object and effect). Further, the invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Further, the invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes configurations in which known techniques are added to the configurations described in the embodiments.

1... Angular velocity detection device, 2... Physical quantity detection circuit (integrated circuit device), 3... Temperature sensor, 4, 4a... Angular velocity detection circuit, 5... Acceleration detection circuit, 6... Selection circuit, 7... ADC, 8... Digital processing circuit , 9... Interface circuit, 10... Fault diagnosis circuit, 11, 16-19... External output terminal, 12-14... External input terminal, 20... Drive circuit, 21, 22... Drive signal, 23... Square wave voltage signal, 30 , 30a... Detection circuit, 31, 32... AC charge (detection current), 36a, 37a... Angular velocity signal, 36b, 37b... Leakage signal, 40, 40a... Abnormality determination circuit, 41, 41a... Error information signal, 42, 42a ... write signal, 43... register, 44... digital signal, 90, 90a, 90b, 90c... composite switch circuit, 93, 93a... comparison signal, 100... gyro sensor element, 101a-101b... drive vibrating arm, 102... detection vibration Arms 103... Weight portions, 104a-104b... Driving base portions, 105a-105b... Connecting arms, 106... Weight portions, 107... Detection base portions, 112-113... Drive electrodes, 114-115... Detection electrodes, 116... Common Electrodes, 210... I/V conversion circuit (current-voltage conversion circuit), 220... AC amplification circuit, 230... Amplitude adjustment circuit, 310, 312... Charge amplifier, 320... Differential amplification circuit, 330... AC amplification circuit, 360, 362... Integrator circuit, 370, 372... DC amplifier circuit, 400x, 400y... Detecting element, 401... Carrier signal, 402-405...
6... Acceleration signal, 407... Error information signal, 408... Temperature signal, 409-413... Signal, 500... Electronic equipment, 520... CPU, 530... Operation part, 540... ROM, 550... RAM, 560... Communication part, 570 ... Display section, 580... Audio output section, 600... Moving body, 620... Controller, 630... Controller, 640... Controller, 650... Battery, 660... Backup battery, 900, 900a... Switch section, 901... First terminal, 902... 2nd terminal, 903... 3rd terminal, 904... 4th terminal, 905... 5th terminal, 906... 6th terminal, 907... 7th terminal, 908... 8th terminal, 909... 9th terminal, 910... 10th terminal, 911... 11th terminal, 912... 12th terminal, 920, 920a, 920b, 920c... Control circuit, 921... Comparator, 922... Inverter, 923... Dividing circuit, 924... Phase shift circuit, 925... Phase shift circuit, 926... Inverter, 930, 930a... Comparison circuit, IN... Input end, IN1... First input end, IN2... Second input end, N1... First node, N2... Second node, N3... Third Node, N4... Fourth node, OUT... Output end, OUT1... First output end, OUT2... Second output end, S1... Control signal, S2... Control signal, S3... Control signal, S4... Control signal, S5... Control Signal, S6... Control signal, SW1... First switch, SW2... Second switch, SW3... Third switch, SW4... Fourth switch, SW5... Fifth switch, SW6... Sixth switch, 1000... Physical quantity detection device

Claims (8)

A composite switch circuit comprising an input terminal and an output terminal,
A first switch including a first terminal and a second terminal, the first terminal being connected to the input end;
A second switch including a third terminal and a fourth terminal, the third terminal being connected to the second terminal, and the fourth terminal being connected to the output end;
A fifth terminal is connected to a first node including a fifth terminal and a sixth terminal, the fifth terminal is connected to the second terminal and the third terminal, and the sixth terminal is connected to a second node. The third switch,
A first control for turning off the first switch and the second switch and turning on the third switch;
A second control for turning on the first switch and the second switch and turning off the third switch;
A control circuit for
A comparator circuit that compares the voltage of the first node and the voltage of the second node at least during the period in which the first control is performed;
Equipped with
The control circuit is
A composite switch circuit for applying a cyclically changing voltage to the second node. The composite switch circuit according to claim 1, wherein
The control circuit is
A composite switch circuit, wherein a voltage that periodically changes during a period in which the first control is performed is applied to the second node. A composite switch circuit comprising a first input end, a second input end, a first output end, and a second output end,
A first switch including a first terminal and a second terminal, the first terminal being connected to the first input end;
A second switch including a third terminal and a fourth terminal, the third terminal being connected to the second terminal, and the fourth terminal being connected to the first output end;
A fifth terminal is connected to a first node including a fifth terminal and a sixth terminal, the fifth terminal is connected to the second terminal and the third terminal, and the sixth terminal is connected to a second node. The third switch,
A fourth switch including a seventh terminal and an eighth terminal, the seventh terminal being connected to the second input end;
A fifth switch including a ninth terminal and a tenth terminal, wherein the ninth terminal is connected to the eighth terminal, and the tenth terminal is connected to the second output end;
An eleventh terminal and a twelfth terminal are included, the eleventh terminal is connected to a third node to which the eighth terminal and the ninth terminal are connected, and the twelfth terminal is connected to a fourth node. The sixth switch,
A first control for turning off the first switch and the second switch and turning on the third switch;
A second control for turning on the first switch and the second switch and turning off the third switch;
A third control for delaying the phase of the first control by 90 degrees for switching the fourth switch and the fifth switch to OFF and switching the sixth switch to ON;
A fourth control for turning on the fourth switch and the fifth switch and turning off the sixth switch;
A control circuit for
A comparator circuit that compares the voltage of the first node with the voltage of the third node at least during a period in which the first control and the third control are performed;
Is a composite switch circuit. A physical quantity detection device comprising a synchronous detection circuit including the composite switch circuit according to claim 1. A synchronous detection circuit including a composite switch circuit,
Register,
An abnormality determination circuit,
Equipped with
The composite switch circuit is
A composite switch circuit comprising an input terminal and an output terminal,
A first switch including a first terminal and a second terminal, the first terminal being connected to the input end;
A second switch including a third terminal and a fourth terminal, the third terminal being connected to the second terminal, and the fourth terminal being connected to the output end;
A fifth terminal is connected to a first node including a fifth terminal and a sixth terminal, the fifth terminal is connected to the second terminal and the third terminal, and the sixth terminal is connected to a second node. The third switch,
A first control for turning off the first switch and the second switch and turning on the third switch;
A second control for turning on the first switch and the second switch and turning off the third switch;
A control circuit for
A comparator circuit that compares the voltage of the first node and the voltage of the second node at least during the period in which the first control is performed;
Equipped with
The abnormality determination circuit,
A physical quantity detection device, wherein the comparison circuit determines that an abnormality has occurred based on the result of the comparison, and writes error information to the register when the result of the determination is abnormal. A synchronous detection circuit including a composite switch circuit,
An abnormality determination circuit,
Equipped with
The composite switch circuit is
A composite switch circuit comprising an input terminal and an output terminal,
A first switch including a first terminal and a second terminal, the first terminal being connected to the input end;
A second switch including a third terminal and a fourth terminal, the third terminal being connected to the second terminal, and the fourth terminal being connected to the output end;
A fifth terminal is connected to a first node including a fifth terminal and a sixth terminal, the fifth terminal is connected to the second terminal and the third terminal, and the sixth terminal is connected to a second node. The third switch,
A first control for turning off the first switch and the second switch and turning on the third switch;
A second control for turning on the first switch and the second switch and turning off the third switch;
A control circuit for
A comparator circuit that compares the voltage of the first node and the voltage of the second node at least during the period in which the first control is performed;
Equipped with
The abnormality determination circuit,
A physical quantity detection device, wherein the comparison circuit determines that an abnormality has occurred based on the result of the comparison, and outputs an error information signal to the outside when the result of the determination is abnormal. An electronic device comprising the composite switch circuit according to claim 1. A mobile body comprising the composite switch circuit according to claim 1.

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