JPH11148829A - Vibration gyro - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration gyro which has small variation of its signal output with a temperature change at a low cost. SOLUTION: The vibration gyro 10 includes an integrated circuit 16 which constitutes a driving detecting circuit. In the integrated circuit 16, a DC amplifier circuit 26 is formed. The DC amplifier circuit 26 consists of a diffused resistor 32 as an input resistor, an external resistor as a feedback resistance, and an operational amplifier circuit 30. The diffused resistor 32 is connected electrically between the output terminal of a filter circuit 24 and the input terminal of the operational amplifier circuit 30. The external resistor 28 is fitted externally to the integrated circuit 16 and connected between the output terminal and inverted input terminal of the operational amplifier circuit 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating gyroscope, and more particularly to, for example, a navigation system which detects a position of a moving body by detecting camera shake, detects a rotational angular velocity, and provides appropriate guidance, or a posture of the moving body. The present invention relates to a vibrating gyroscope for detecting a rotational angular velocity used for control.

[0002]

2. Description of the Related Art FIG. 13 is a block diagram showing an example of a conventional vibrating gyroscope, and FIG. 14 is a block diagram showing another example of a conventional vibrating gyroscope. These vibrating gyroscopes 1 include a vibrating body 2 having, for example, a regular triangular prism shape. Piezoelectric elements 3a, 3b, 3c are formed on the side surfaces of the vibrating body 2, respectively. The piezoelectric elements 3a and 3b are used for driving to cause the vibrating body 2 to bend and vibrate, and are also used for detecting a signal corresponding to the rotational angular velocity. The piezoelectric element 3c is used for feedback. That is, the vibrator of the vibrating gyroscope 1 is composed of the vibrating body 2 and the piezoelectric elements 3a, 3b, 3c. An oscillation circuit 4 is connected between the piezoelectric elements 3a and 3b and the piezoelectric element 3c. Further, the piezoelectric elements 3 a and 3 b are connected to the input terminals of the differential circuit 5. The output terminal of the differential circuit 5 is connected to a synchronous detection circuit 6, and the synchronous detection circuit 6 is further connected to a smoothing circuit 7. The output terminal of the smoothing circuit 7 is connected to the DC amplifier circuit 8.

In the vibrating gyroscope 1, the vibrating body 2 bends and vibrates in a direction orthogonal to the surface on which the piezoelectric element 3c is formed by a driving signal from an oscillation circuit 4. In this state, when the vibrating body 2 rotates around the axis, the vibrating direction of the vibrating body 2 changes due to the Coriolis force. Thereby, the detecting piezoelectric elements 3a, 3
A difference in the output signal occurs between b and the difference between the output signals is output from the differential circuit 5. Then, by detecting and smoothing the output of the differential circuit 5 and further amplifying it, a signal corresponding to the rotational angular velocity applied to the vibrating gyroscope 1 can be detected.

[0004]

However, the vibrating gyroscope 1 has a piezoelectric element 3 for detection based on a change in ambient temperature.
Since the output signals from a and 3b fluctuate and the detection sensitivity changes, it is necessary to correct the temperature characteristics of the detection sensitivity.
Therefore, conventionally, a temperature characteristic correcting component 9 such as a thermistor or a positive linear temperature characteristic resistor and the chip resistor R are connected to the input resistance or feedback resistance of the operational amplifier constituting the DC amplifier circuit 8 as shown in FIGS. To adjust the gain of the DC amplification circuit 8 with respect to a temperature change. That is, the gain of the DC amplifier circuit 8 is adjusted so as to make a change opposite to the change in the output signals from the piezoelectric elements 3a and 3b, and the temperature change of the final output signal is adjusted to be small. However, in this case, there is a problem that it is difficult to reduce the cost of the product because the temperature characteristic correcting component 9 is expensive.

Therefore, a main object of the present invention is to provide an inexpensive vibrating gyroscope in which the output signal changes little with temperature.

[0006]

A vibrating gyroscope according to the present invention includes a diffused resistor formed inside an integrated circuit constituting a detecting circuit of a vibrator and an external resistor externally attached to the integrated circuit. In order to correct the sensitivity temperature characteristics of the gyro, by incorporating a diffusion resistor and an external resistor with different temperature characteristics into the detection circuit, the circuit gain of the detection system has a temperature characteristic that cancels out the sensitivity temperature characteristics of the resonator. It is a vibrating gyro. Usually, the external resistance and the diffusion resistance have different temperature characteristics. Utilizing this, the temperature characteristic of the circuit gain of the detection system can be adjusted at low cost by incorporating a diffusion resistor and an external resistor having different temperature characteristics into the detection circuit. With the temperature characteristic of the circuit gain of the detection system, the temperature characteristic of the detection sensitivity of the vibrator can be canceled and corrected, and the change due to the temperature of the final output signal of the vibrating gyroscope can be reduced. Further, by using the diffusion resistor, the number of components externally provided to the integrated circuit can be reduced.

In the vibrating gyroscope according to the present invention, one of the diffused resistor and the external resistor is connected as an input resistor to an inverting input terminal of an operational amplifier formed in the integrated circuit, and the other is connected to the operational amplifier. It may be connected as a feedback resistor between the output terminal and the inverting input terminal. The input resistance and the feedback resistance of the operational amplifier according to the present invention are resistors that determine the circuit gain of the inverting amplifier. Therefore, by connecting one of the external resistance and the diffusion resistance having different temperature characteristics to each other as the input resistance of the operational amplifier and connecting the other as the feedback resistance, the temperature characteristic of the circuit gain of the detection system including the inverting amplifier can be improved. It can be adjusted inexpensively. With the temperature characteristic of the circuit gain of the detection system, the temperature characteristic of the detection sensitivity of the vibrator can be canceled and corrected, and the change due to the temperature of the final output signal of the vibrating gyroscope can be reduced.

Further, in the vibrating gyroscope according to the present invention, one of the diffusion resistor and the external resistor is connected between an inverting input terminal of an operational amplifier formed in an integrated circuit and a reference potential, and the other is connected to the reference potential. It may be connected as a feedback resistor between the output terminal and the inverting input terminal of the operational amplifier. The resistor and the feedback resistor connected between the inverting input terminal of the operational amplifier and the reference potential in the present invention are resistors that determine the circuit gain of the non-inverting amplifier. Therefore, by connecting one of the external resistor and the diffused resistor having different temperature characteristics between the inverting input terminal of the operational amplifier and the reference potential, and connecting the other as a feedback resistor, the detection including the non-inverting amplifier is performed. The temperature characteristics of the circuit gain of the system can be adjusted at low cost. With the temperature characteristic of the circuit gain of the detection system, the temperature characteristic of the detection sensitivity of the vibrator can be canceled and corrected, and the change due to the temperature of the final output signal of the vibrating gyroscope can be reduced.

Further, in the vibrating gyroscope according to the present invention, a plurality of operational amplifiers to which a diffused resistor and an external resistor are connected may be formed in an integrated circuit, and they may be connected in series with each other. By connecting a plurality of operational amplifiers in which a diffused resistor and an external resistor are connected as described above in series, a change in circuit gain due to temperature can be further increased. Therefore, even when the change in the rotational angular velocity detection sensitivity of the vibrator due to the temperature is large, the change due to the temperature of the final output signal can be reduced.

In the vibrating gyroscope according to the present invention, a voltage dividing circuit may be formed by the diffused resistor and the external resistor, and the voltage dividing circuit may be incorporated in the detecting circuit. The temperature characteristic of the circuit gain of the detection system can also be adjusted at low cost by forming a voltage divider circuit with a diffusion resistor and an external resistor having different temperature characteristics from each other and incorporating the voltage divider circuit into the detection circuit.
With the temperature characteristic of the circuit gain of the detection system, the temperature characteristic of the detection sensitivity of the vibrator can be canceled and corrected, and the change due to the temperature of the final output signal of the vibrating gyroscope can be reduced.

Further, another vibrating gyroscope according to the present invention includes a plurality of diffused resistors having different temperature characteristics formed inside an integrated circuit constituting a vibrator detecting circuit, and corrects the sensitivity temperature characteristics of the vibrating gyroscope. A vibration gyro that forms a voltage divider circuit with a diffused resistor, incorporates the voltage divider circuit into a detection circuit, and gives the circuit gain of the detection system a temperature characteristic that offsets the sensitivity temperature characteristic of the vibrator. . A voltage divider circuit is formed by a plurality of diffusion resistors with different temperature characteristics,
By incorporating the voltage dividing circuit in the detection circuit, the temperature characteristics of the circuit gain of the detection system can be adjusted at low cost. With the temperature characteristic of the circuit gain of the detection system, the temperature characteristic of the detection sensitivity of the vibrator can be canceled and corrected, and the change due to the temperature of the final output signal of the vibrating gyroscope can be reduced. In the case of the present invention,
This is also useful in that the number of external components can be further reduced.

In the present invention, the temperature characteristic is 150
Diffusion resistance of 0-2500 ppm / ° C and 4000-500
A diffusion resistance of 0 ppm / ° C. may be used in series or in parallel. The temperature characteristic of the diffusion resistance changes depending on the amount of impurities doped into the semiconductor in the step of forming the resistance. Therefore, the temperature characteristic is 1500 to 2500
ppm / ° C diffusion resistance and 4000-5000 ppm / ° C
By forming these diffusion resistors in an integrated circuit and connecting them in series or in parallel, the temperature characteristics of the circuit gain of the detection system can be adjusted to a desired state.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention with reference to the accompanying drawings.

[0014]

FIG. 1 is a block diagram showing a first embodiment of a vibrating gyroscope according to the present invention. A vibrating gyroscope 10 shown in FIG. 1 includes a regular triangular prism-shaped vibrating body 12 formed of, for example, an elinvar. Piezoelectric elements 14a, 14b, 14c are formed on the side surfaces of the vibrating body 12, respectively. The piezoelectric elements 14a and 14b are used for driving the vibrating body 12 to bend and vibrate, and are also used for detecting a signal corresponding to the rotational angular velocity. The piezoelectric element 14c is used for feedback. That is, in the vibrating gyroscope 10, the vibrating body 12 and the piezoelectric elements 14a, 14b and 14c form the vibrator 15
Are formed. The vibrating body 12 is not limited to a metal triangular prism formed of an elinvar, but may be a metal quadrangular prism, a ceramic triangular prism, a ceramic quadrangular prism, a ceramic cylinder, a ceramic bimorph, or the like.

The vibrating gyroscope 10 includes an integrated circuit 16 in which a drive circuit and a detection circuit are formed. As the integrated circuit 16, for example, a bipolar custom IC is used. An oscillation circuit 18 is formed in the integrated circuit 16 as a circuit for forming a drive system. The oscillation circuit 18 is connected between the piezoelectric elements 14a and 14b and the piezoelectric element 14c. Further, the integrated circuit 16
Inside, a differential circuit 2 is provided as a circuit for forming a detection system.
0, a synchronous detection circuit 22, a smoothing circuit 24, and a DC amplification circuit 26 are connected in series and formed. Two input terminals of the differential circuit 20 are connected to the piezoelectric elements 14a and 14b. The output signal of the differential circuit 20 is synchronously detected by the synchronous detection circuit 22 based on the signal from the oscillation circuit 18. Then, the output signal of the synchronous detection circuit 22 is smoothed by the smoothing circuit 24, and then amplified and output by the DC amplifier circuit 26.

The DC amplifier 26 includes an external resistor 28 as a feedback resistor, a diffused resistor 32 as an input resistor, and an operational amplifier 30. The external resistor 28 is externally attached to the integrated circuit 16, and for example, a chip resistor is used. The external resistor 28 is connected between the output terminal of the operational amplifier 30 and the inverting input terminal. This external resistor 28 can be regarded as having almost no change in resistance value due to temperature. On the other hand, the diffused resistor 32 is
The semiconductor substrate is formed by doping impurities. The diffusion resistor 32 is electrically connected between the output terminal of the smoothing circuit 24 and the input terminal of the operational amplifier 30. The diffusion resistor 32 has a positive temperature characteristic in which the resistance value changes in proportion to the temperature.
0 ppm / ° C or about 4000-5000p
pm / ° C is common.

In the vibrating gyroscope 10, the vibrating body 12 bends and vibrates in a direction orthogonal to the surface on which the piezoelectric element 14c is formed by a driving signal from an oscillation circuit 18. In this state, when the vibrating body 12 rotates about the axis, the vibrating direction of the vibrating body 12 changes due to the Coriolis force. As a result, a difference between output signals is generated between the piezoelectric elements 14a and 14b, and the difference between the output signals is output from the differential circuit 20. The output of the differential circuit 20 is detected, smoothed, and further amplified to obtain a signal corresponding to the rotational angular velocity applied to the vibrating gyroscope 10.

Further, since the vibration gyro 10 has the above-described circuit configuration, the circuit gain of the detection system is reduced as shown in FIG.
It has a temperature characteristic as shown in FIG. That is, the temperature characteristic of the circuit gain of the vibrating gyroscope 10 is such that the external resistance value is R _ext and the diffusion resistance value is R _int.
Assuming that the amount of change in the diffusion resistance value per temperature based on the resistance value at 5 ° C. is ΔR _int , R _ext can be regarded as substantially constant, so that R _ext / (R _int + ΔR _int × (T−25)
°)). Therefore, the temperature characteristic of the circuit gain of the vibrating gyroscope 10 is such that the circuit gain increases on the low temperature side and decreases on the high temperature side with reference to the circuit gain at 25 ° C. Therefore, in the vibrating gyroscope 10, when the rotational angular velocity detection sensitivity of the vibrator 15 has a temperature characteristic lower on the low temperature side and higher on the high temperature side with reference to the sensitivity at 25 ° C. as shown in FIG. In addition, the temperature characteristics can be offset. As a result, in the vibrating gyroscope 10, as shown in FIG. 2C, a change in the final output signal due to the temperature is small, and a flat sensitivity-temperature characteristic can be obtained. Therefore, according to the vibrating gyroscope 10, it is not necessary to use expensive components such as thermistors for adjusting the temperature characteristic of the circuit gain unlike the related art, and the number of components can be reduced. A vibrating gyroscope with a small change due to temperature can be obtained at low cost.

FIG. 3 is a block diagram showing a second embodiment of the vibrating gyroscope according to the present invention. In the vibration gyro 40 shown in FIG. 3, the same components as those in the vibration gyro 10 shown in FIG. In the vibrating gyroscope 40 shown in FIG. 3, an external resistor 28 is connected as an input resistor to an inverting input terminal of an operational amplifier 30 formed in an integrated circuit, and a diffused resistor 32
Is connected as a feedback resistor between the output terminal and the inverting input terminal of the operational amplifier 30.

The vibrating gyroscope 40 has a temperature characteristic as shown in FIG. That is, the temperature characteristic of the circuit gain of the vibrating gyroscope 40 is obtained by setting the external resistance value to R _ext and the diffusion resistance value to R _int , for example, the change of the diffusion resistance value per temperature based on the resistance value at 25 ° C. If the amount is ΔR _int , R _ext
Can be regarded as almost constant, (R _int + ΔR _int × (T
-25 °)) / _Rext . Therefore, the temperature characteristic of the circuit gain of the vibrating gyroscope 40 is such that the circuit gain decreases on the low temperature side and increases on the high temperature side with reference to the circuit gain at 25 ° C. Therefore, in the vibrating gyroscope 40, the vibrator 15
4B, the rotation angular velocity detection sensitivity is 2 as shown in FIG.
When the temperature characteristic rises on the low temperature side and decreases on the high temperature side based on the sensitivity at 5 ° C., the temperature characteristic can be offset. As a result, in the vibrating gyroscope 40, as shown in FIG. 4C, a change in the final output signal due to the temperature is small, and a flat sensitivity temperature characteristic can be obtained. Therefore, the same effects as in the first embodiment described above can be obtained by the vibrating gyroscope 40 shown in FIG.

FIG. 5 is a circuit diagram showing a connection state of diffusion resistors in a modified example of the vibrating gyroscope according to the present invention.
In the first and second embodiments described above, a single diffusion resistor is used. However, when a diffusion resistor having a temperature characteristic of 1500 to 2500 ppm / ° C. is used alone, FIG. As shown by the straight line plotted with black circles in A), there may be cases where the temperature characteristics of the vibrator 15 cannot be corrected completely. On the other hand, the temperature characteristics as diffusion resistance
When 5000 ppm / ° C. was used alone, FIG.
As shown by a straight line plotted by a white square in (B), the temperature characteristic of the vibrator 15 may be overcorrected. Therefore, in order to correct these inconveniences, as shown in FIG. 5A and FIG.
A diffusion resistance R1 of 00 ppm / ° C. and a temperature characteristic of 4000
The combined resistance obtained by connecting the diffusion resistance R2 of ０００5000 ppm / ° C. in series or in parallel can be used as the diffusion resistance R _int in each of the above embodiments. In this case, the temperature characteristics of the diffused resistor R _int can be adjusted to a desired state by a combination of the diffused resistor R1 and the diffused resistor R2. Therefore, in the case shown in FIG. 6A or FIG. Also, a vibration gyro having a flat sensitivity temperature characteristic can be obtained. Although FIG. 5 shows an example in which two diffused resistors are connected in series or in parallel, more diffused resistors may be connected in series or in parallel.

FIG. 7 is a block diagram showing a third embodiment of the vibrating gyroscope according to the present invention. In the vibration gyro 50 shown in FIG. 7, the same components as those in the vibration gyro 10 shown in FIG. The vibration gyro 50 shown in FIG. 7 is different from the vibration gyro 10 shown in FIG.
Are different. That is, in the vibrating gyroscope 50, the operational amplifier 30 and the operational amplifier 31 are provided in the integrated circuit 16.
Are formed, and these two operational amplifiers 30 and 31 are connected in series to form a DC amplifier circuit 26. The operational amplifier 30 of the DC amplification circuit 26 is connected to the smoothing circuit 24 via a diffusion resistor 32 as an input resistor. Also,
An external resistor 28 as a feedback resistor is connected to the operational amplifier 30. Further, an output terminal of the operational amplifier 30 is connected to an operational amplifier 31 via a diffusion resistor 33 as an input resistor. An external resistor 29 is connected to the operational amplifier 31 as a feedback resistor. Then, a signal corresponding to the rotational angular velocity applied to the vibration gyro 50 can be obtained from the output terminal of the operational amplifier 31.

Since the vibrating gyroscope 50 shown in FIG. 7 has two stages of operational amplifiers, the circuit gain of the circuit gain is reduced as shown by a straight line plotted by a white circle in FIG. The slope of the temperature characteristic can be made larger. Therefore, even if the sensitivity of the vibrator 15 greatly changes with temperature, as shown by the straight line plotted with a cross in FIG. 9A, it is possible to reduce the final change of the output signal with temperature. As a result, a flat sensitivity-temperature characteristic can be obtained as indicated by a straight line plotted by triangles.

FIG. 8 is a block diagram showing a fourth embodiment of the vibrating gyroscope according to the present invention. In the vibrating gyroscope 60 shown in FIG. 8, the same components as those of the vibrating gyroscope 40 shown in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. The vibration gyro 60 shown in FIG. 8 is different from the vibration gyro 40 shown in FIG.
Are different. That is, in the vibrating gyroscope 60, the operational amplifier 30 and the operational amplifier 31 are provided in the integrated circuit 16.
Are formed, and two operational amplifiers 30 and 31 are connected in series to form a DC amplifier circuit 26. The operational amplifier 30 of the DC amplifier circuit 26 is connected to the smoothing circuit 24 via an external resistor 28 as an input resistor. Further, a diffusion resistor 32 as a feedback resistor is connected to the operational amplifier 30. Further, an output terminal of the operational amplifier 30 is connected to an operational amplifier 31 via an external resistor 29 as an input resistor. The operational amplifier 31 is connected with a diffusion resistor 33 as a feedback resistor. Then, a signal corresponding to the rotational angular velocity applied to the vibration gyro 60 can be obtained from the output terminal of the operational amplifier 31.

Since the vibrating gyroscope 60 shown in FIG. 8 has two stages of operational amplifiers, the circuit gain of the circuit gain can be reduced as shown by a straight line plotted by a white circle in FIG. The slope of the temperature characteristic can be made larger. Therefore, even when the sensitivity of the vibrator 15 greatly changes with temperature as shown by the straight line plotted with a cross in FIG. 9B, the final change of the output signal with temperature can be reduced. , A flat sensitivity-temperature characteristic can be obtained as indicated by a straight line plotted by triangles.

In the vibrating gyroscopes 50 and 60 shown in FIGS.
May have the same characteristics or different characteristics.
This is the same for the external resistors 28 and 29. Further, in order to obtain a desired temperature characteristic, the diffusion resistance 32
As 33, a combined resistor as shown in FIG. 5 may be used. The vibration gyro 5 shown in FIGS.
In 0 and 60, the number of operational amplifiers is not limited to two, but may be more.

FIG. 10 is a circuit diagram showing a modification of the DC amplifier circuit 26 used in the vibrating gyroscope according to the present invention. In the DC amplification circuit 26 of each of the above embodiments,
Although the operational amplifier 30 is used as an inverting amplifier, the DC amplifier circuit 26 shown in FIG. 10 uses the operational amplifier 30 as a non-inverting amplifier. That is, in the DC amplification circuit 26, the inverting input terminal of the operational amplifier 30 is connected to the reference potential via the first resistor R1. A second resistor R2 is connected between the output terminal and the inverting input terminal of the operational amplifier 30 as a feedback resistor. In this case, the gain of the DC amplifier circuit 26 is determined by the _{(R 1 + R 2) /} R 1. Therefore, an external resistor is used for one of the first resistor R1 and the second resistor R2 and a diffused resistor is used for the other, or a diffused resistor having different temperature characteristics is used for both.
By configuring the DC amplification circuit 26 of each of the above embodiments, the same effects as those described above can be obtained.

FIG. 11 is a block diagram showing a fifth embodiment of the vibrating gyroscope according to the present invention.
FIG. 2 is a circuit diagram showing an example of a voltage dividing circuit of the vibrating gyroscope shown in FIG. In the fifth embodiment, the voltage dividing circuit 34 is incorporated in the detection system of the vibration gyro.
The characteristic is that the temperature characteristic of the circuit gain is adjusted by the method. As shown in FIG. 12, the voltage dividing circuit 34 includes a second resistor R2 connected between one end of a first resistor R1 connected in series to a detection system and a reference potential. In this case, with the relationship of _{Vout = (R 2 / (R} 1 + R 2)) · V in. Accordingly, the temperature characteristic of the circuit gain can be adjusted by using either _one of R ₁ and R ₂ as an external resistor and the other as a diffused resistor, or using both diffused resistors with different temperature characteristics. The same effects as those of the above embodiments can be obtained. In addition,
In FIG. 11, the voltage dividing circuit 34 includes the vibrator 15 and the differential circuit 20.
Although the connection between the synchronous detection circuit 22 and the smoothing circuit 24 may be provided between the differential circuit 20 and the synchronous detection circuit 22, the connection is not limited thereto. And may be connected between the smoothing circuit 24 and the DC amplifier circuit 26. Similar effects can be obtained in these cases.

In the description of the above embodiment,
The vibration gyro in which the external resistance and the diffusion resistance are connected to the operational amplifier forming the DC amplification circuit has been described. However, the external resistance and the diffusion resistance are connected to the operation amplifier forming the differential circuit, and the circuit gain of the detection system is obtained. May be adjusted.

[0030]

As described above, according to the vibrating gyroscope according to the present invention, it is not necessary to use expensive components such as thermistors for adjusting the temperature characteristics of the circuit gain as in the prior art, and the number of components can be reduced. Therefore, a vibrating gyroscope with a small change in the detection sensitivity of the rotational angular velocity due to the temperature can be obtained at low cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a vibrating gyroscope according to the present invention.

2A is a graph showing a temperature characteristic of a circuit gain of a detection system of the vibration gyro shown in FIG. 1, and FIG.
3 is a graph showing sensitivity temperature characteristics of the vibrator of the vibrating gyroscope shown in FIG. 1, and (C) is a graph showing sensitivity temperature characteristics of the vibrating gyroscope shown in FIG.

FIG. 3 is a block diagram showing a vibration gyro according to a second embodiment of the present invention.

4A is a graph showing a temperature characteristic of a circuit gain of a detection system of the vibration gyro shown in FIG. 3, and FIG.
4 is a graph showing sensitivity temperature characteristics of the vibrator of the vibrating gyroscope shown in FIG. 3, and FIG. 4C is a graph showing sensitivity temperature characteristics of the vibrating gyroscope shown in FIG.

FIG. 5A is a circuit diagram showing an example of a connection state of diffusion resistors in a modified example of the vibrating gyroscope according to the present invention, and FIG. 5B is a circuit diagram showing another example.

FIG. 6A shows a case where the absolute value of the slope of the temperature characteristic of the circuit gain is smaller than the absolute value of the slope of the temperature characteristic of the sensitivity of the oscillator; FIG. On the other hand, in (B), since the absolute value of the slope of the temperature characteristic of the circuit gain is larger than the absolute value of the slope of the temperature characteristic of the sensitivity of the oscillator, the temperature characteristic of the oscillator is overcorrected, and 9 is a graph showing an example in which the temperature characteristic of sensitivity does not become flat.

FIG. 7 is a block diagram showing a third embodiment of the vibrating gyroscope according to the present invention.

FIG. 8 is a block diagram showing a vibration gyro according to a fourth embodiment of the present invention.

9A is a diagram showing a temperature characteristic of a circuit gain of the detection system of the vibration gyro shown in FIG. 7, a temperature characteristic of sensitivity of the vibrator,
6 is a graph showing a relationship between sensitivity of a vibrating gyroscope and temperature characteristics. 8B is a graph showing the relationship between the temperature characteristics of the circuit gain of the detection system of the vibration gyro shown in FIG. 8, the temperature characteristics of the sensitivity of the vibrator, and the temperature characteristics of the sensitivity of the vibration gyro.

FIG. 10 is a circuit diagram showing a modification of the DC amplifier circuit used in the vibrating gyroscope according to the present invention.

FIG. 11 is a block diagram showing a fifth embodiment of the vibrating gyroscope according to the present invention.

FIG. 12 is a circuit diagram showing an example of a voltage dividing circuit used in the vibration gyro shown in FIG.

FIG. 13 is a block diagram showing an example of a conventional vibrating gyroscope.

FIG. 14 is a block diagram showing another example of a conventional vibrating gyroscope.

[Explanation of symbols]

 10, 40, 50, 60 Vibration gyroscope 12 Vibration body 14a, 14b, 14c Piezoelectric element 15 Vibrator 16 Integrated circuit 18 Oscillation circuit 20 Differential circuit 22 Synchronous detection circuit 24 Smoothing circuit 26 DC amplification circuit 28, 29 External resistance 30, 31 operational amplifier 32,33 diffused resistor 34 voltage divider circuit

Claims (7)

[Claims] 1. A semiconductor device comprising: a diffused resistor formed inside an integrated circuit forming a vibrator detection circuit; and an external resistor attached to the integrated circuit from the outside. A vibration gyro in which the diffusion resistance and the external resistance having different temperature characteristics from each other are incorporated in the detection circuit, so that a circuit gain of a detection system has a temperature characteristic to offset a sensitivity temperature characteristic of the vibrator. 2. One of the diffusion resistance and the external resistance is connected as an input resistance to an inverting input terminal of an operational amplifier formed in the integrated circuit, and the other is connected to an output terminal of the operational amplifier and the output terminal of the operational amplifier. The vibrating gyroscope according to claim 1, wherein the vibrating gyroscope is connected as a feedback resistor between the inverting input terminal and the inverting input terminal. 3. One of the diffusion resistance and the external resistance is connected between an inverting input terminal of an operational amplifier formed in the integrated circuit and a reference potential, and the other is an output of the operational amplifier. The vibrating gyroscope according to claim 1, wherein the vibrating gyroscope is connected as a feedback resistor between a terminal and the inverting input terminal. 4. An integrated circuit comprising: a plurality of the operational amplifiers each having the diffused resistor and the external resistor connected to each other;
The vibrating gyroscope according to claim 2 or 3, wherein the vibrating gyroscopes are connected to each other in series. 5. The vibrating gyroscope according to claim 1, wherein a voltage dividing circuit is formed by the diffusion resistor and the external resistor, and the voltage dividing circuit is incorporated in the detection circuit. 6. A semiconductor device comprising a plurality of diffusion resistors formed inside an integrated circuit constituting a detection circuit of a vibrator and having different temperature characteristics from each other. In order to correct sensitivity temperature characteristics of the vibrating gyroscope, a voltage is divided by the diffusion resistors. A vibration gyro in which a circuit is formed, and the voltage dividing circuit is incorporated in the detection circuit, and a circuit gain of a detection system has a temperature characteristic that cancels a sensitivity temperature characteristic of the vibrator. 7. A temperature characteristic of 1500 to 2500 ppm /
The vibrating gyroscope according to any one of claims 2 to 6, wherein a diffusion resistance of ° C and a diffusion resistance of 4000 to 5000 ppm / ° C are connected in series or in parallel.