JP2016187132A - Oscillators, electronic devices and mobile objects - Google Patents

Abstract

An oscillator capable of reducing fluctuations in frequency, and an electronic apparatus and a moving body using the same are provided.
An oscillator includes an oscillator, an oscillation circuit that resonates the oscillator and outputs an oscillation signal, a high potential side of a power supply, and a power supply node on a high potential side of the oscillation circuit. A first noise attenuation circuit 31 disposed on a signal path between a certain first power supply node 21, a second power supply that is a power supply node on the high potential side of the power supply and a low potential side of the oscillation circuit 20 And a second noise attenuation circuit 32 disposed on the signal path between the node 22 and the node 22.
[Selection] Figure 1

Description

  The present invention relates to an oscillator, an electronic device, and a moving object.

  An oscillator using a vibrator such as a quartz vibrator (piezoelectric vibrator) or a MEMS (Micro Electro Mechanical Systems) vibrator is known.

  Patent Document 1 discloses a semiconductor integrated circuit in which a power supply and an oscillation circuit are connected via a regulator.

JP-A-8-204450

  When the power supply voltage supplied to the oscillation circuit varies, the oscillation frequency of the oscillation circuit varies. In the semiconductor integrated circuit of Patent Document 1, since a voltage is supplied via a regulator to the power supply node on the high potential side of the oscillation circuit, it can be expected that fluctuations in the power supply voltage are alleviated to some extent. However, it may be insufficient in applications that require high accuracy with respect to frequency fluctuations.

  The present invention has been made in view of the above technical problems. According to some embodiments of the present invention, it is possible to provide an oscillator that can reduce frequency fluctuations, and an electronic apparatus and a moving body using the oscillator.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

[Application Example 1]
The oscillator according to this application example is
A vibrator,
An oscillation circuit for resonating the vibrator and outputting an oscillation signal;
A first noise attenuation circuit disposed on a signal path between a high potential side of a power supply and a first power supply node that is a power supply node on the high potential side of the oscillation circuit;
A second noise attenuation circuit disposed on a signal path between a high potential side of the power supply and a second power supply node which is a power supply node on the low potential side of the oscillation circuit;
It is an oscillator containing.

  According to this application example, since the fluctuation of the power supply voltage supplied to the oscillation circuit is attenuated on both the high potential side and the low potential side, an oscillator capable of reducing the frequency fluctuation can be realized.

[Application Example 2]
In the above oscillator,
The first noise attenuation circuit is a first regulator that generates a voltage based on a reference voltage;
The second noise attenuation circuit may be a second regulator that generates a voltage based on the reference voltage.

  According to this application example, even if the reference voltage fluctuates, the output of the first regulator and the output of the second regulator fluctuate in phase, so that they cancel each other out in the oscillation circuit. In addition, the fluctuation due to noise wrapping due to capacitive coupling between the power supply and the output of the first regulator and the fluctuation due to noise wrapping due to capacitive coupling between the power supply and the output of the second regulator are also in phase. Therefore, the oscillation circuits cancel each other. Therefore, it is possible to realize an oscillator that can reduce frequency fluctuations.

[Application Example 3]
In the above oscillator,
The first noise attenuation circuit and the second noise attenuation circuit may be filters.

  According to this application example, it is possible to realize an oscillator capable of reducing frequency fluctuations with a simple configuration.

[Application Example 4]
In the above oscillator,
A control voltage generation circuit for generating a control voltage for controlling the oscillation frequency of the oscillation circuit;
A third power supply node that is a power supply node on the high potential side of the control voltage generation circuit is connected to the first power supply node,
A fourth power supply node that is a power supply node on the low potential side of the control voltage generation circuit may be connected to the second power supply node.

  According to this application example, since the control voltage fluctuates in phase with the fluctuation of the power supply, the oscillation circuits cancel each other. Therefore, it is possible to realize an oscillator that can reduce frequency fluctuations.

[Application Example 5]
In the above oscillator,
A temperature compensation circuit for compensating frequency frequency characteristics of the vibrator may be further included.

  According to this application example, since the frequency temperature characteristic of the vibrator is compensated, it is possible to realize an oscillator capable of reducing frequency fluctuations.

[Application Example 6]
In the above oscillator,
A heating element may be further included.

  According to this application example, since the temperature of the vibrator and the oscillation circuit can be easily maintained at a desired temperature, an oscillator capable of reducing frequency fluctuation can be realized.

[Application Example 7]
In the above oscillator,
A temperature sensitive element may further be included.

  According to this application example, since the temperature of the vibrator and the oscillation circuit can be detected, the temperature compensation circuit and the heating element can be appropriately controlled. Therefore, it is possible to realize an oscillator that can reduce frequency fluctuations.

[Application Example 8]
The electronic device according to this application example is
An electronic device including any of the above-described oscillators.

  According to this application example, since the oscillator that can reduce the fluctuation of the frequency is provided, an electronic apparatus with high operation reliability can be realized.

[Application Example 9]
The mobile object according to this application example is
It is a moving object provided with one of the above-mentioned oscillators.

  According to this application example, since the oscillator that can reduce the fluctuation of the frequency is provided, it is possible to realize a moving body with high operation reliability.

It is a functional block diagram of the oscillator concerning a 1st embodiment. It is a circuit diagram which shows the structural example of a 1st noise attenuation circuit and a 2nd noise attenuation circuit. It is a functional block diagram of the oscillator concerning a 2nd embodiment. It is a functional block diagram of the oscillator concerning a 3rd embodiment. It is a functional block diagram of the oscillator concerning a 4th 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 body which concerns on this embodiment.

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

1. Oscillator 1-1. First Embodiment FIG. 1 is a functional block diagram of an oscillator 1 according to a first embodiment.

  The oscillator 1 according to the present embodiment includes a vibrator 10, an oscillation circuit 20, a first noise attenuation circuit 31, and a second noise attenuation circuit 32.

  The vibrator 10 and the oscillation circuit 20 constitute an oscillation circuit using the vibrator 10 as an oscillation element.

  As the vibrator 10, for example, an SC cut or AT cut crystal vibrator, a SAW (Surface Acoustic Wave) resonator, or the like can be used. Further, as the vibrator 10, for example, a piezoelectric vibrator other than a crystal vibrator, a MEMS (Micro Electro Mechanical Systems) vibrator, or the like can be used. As a substrate material of the vibrator 10, a piezoelectric single crystal such as crystal, lithium tantalate, or lithium niobate, a piezoelectric material such as piezoelectric ceramics such as lead zirconate titanate, or a silicon semiconductor material can be used. Further, as the excitation means of the vibrator 10, one using a piezoelectric effect may be used, or electrostatic driving using Coulomb force may be used.

  As the oscillation circuit, various known oscillation circuits such as a Colpitts oscillation circuit, a Hartley oscillation circuit, and an inverter type oscillation circuit can be employed.

  The oscillation circuit 20 has a first power supply node 21 that is a power supply node on the high potential side and a second power supply node 22 that is a power supply node on the low potential side. The oscillation circuit 20 is supplied with power through the first power supply node 21 and the second power supply node 22. The oscillation circuit 20 outputs an oscillation signal from the output terminal OUT.

  The first noise attenuation circuit 31 is arranged on a signal path between the high potential side (terminal Vcc) of the power supply and the first power supply node 21 of the oscillation circuit 20. The first noise attenuation circuit 31 attenuates at least a part of noise input from the high potential side (terminal Vcc) of the power supply. In the present embodiment, the first noise attenuating circuit 31 includes a first regulator 310 that receives a power supply potential and a ground potential and generates a voltage V1.

  The second noise attenuation circuit 32 is arranged on a signal path between the high potential side (terminal Vcc) of the power supply and the second power supply node 22 of the oscillation circuit 20. The second noise attenuation circuit 32 attenuates at least a part of noise input from the high potential side (terminal Vcc) of the power supply. In the present embodiment, the second noise attenuating circuit 32 is configured by a second regulator 320 that receives a power supply potential and a ground potential and generates a voltage V2 lower than the voltage V1.

  According to the present embodiment, since the fluctuation of the power supply voltage supplied to the oscillation circuit 20 is attenuated on both the high potential side and the low potential side, the oscillator 1 that can reduce the fluctuation in frequency can be realized.

  FIG. 2 is a circuit diagram showing a configuration example of the first noise attenuation circuit 31 and the second noise attenuation circuit 32.

  The first noise attenuation circuit 31 of the present embodiment is a first regulator 310 that generates a voltage based on the reference voltage Vr, and the second noise attenuation circuit 32 is a second regulator that generates a voltage based on the reference voltage Vr. 320.

  In the example shown in FIG. 2, the first regulator 310 is a push-type regulator that includes an amplifier circuit A1, a PMOS transistor M1, a current source circuit I1, a capacitor C1, a resistor R11, and a resistor R12. The reference voltage Vr is input from the reference voltage generation circuit 330 to the non-inverting input terminal of the amplifier circuit A1. The output terminal of the amplifier circuit A1 is connected to the gate of the PMOS transistor M1. The PMOS transistor M1 and the current source circuit I1 are connected in series in order from the power source to the ground. The source of the PMOS transistor M1 is connected to the power supply, and the drain of the PMOS transistor M1 is connected to the current source circuit I1, and is connected to one end of the resistor R12 and one end of the capacitor C1, and serves as the output terminal of the first regulator 310. . The other end of the resistor R12 is connected to the inverting input terminal of the amplifier circuit A1, and is connected to the ground via the resistor R11. The other end of the capacitor C1 is connected to the ground.

  In the example shown in FIG. 2, the second regulator 320 is a push-type regulator that includes an amplifier circuit A2, a PMOS transistor M2, a current source circuit I2, a capacitor C2, a resistor R21, and a resistor R22. The reference voltage Vr is input from the reference voltage generation circuit 330 to the non-inverting input terminal of the amplifier circuit A2. The output terminal of the amplifier circuit A2 is connected to the gate of the PMOS transistor M2. The PMOS transistor M2 and the current source circuit I2 are sequentially connected in series between the power source and the ground. The source of the PMOS transistor M2 is connected to the power supply, the drain of the PMOS transistor M2 is connected to the current source circuit I2, and is connected to one end of the resistor R22 and one end of the capacitor C2, and serves as the output terminal of the second regulator 320. . The other end of the resistor R22 is connected to the inverting input terminal of the amplifier circuit A2, and is connected to the ground via the resistor R21. The other end of the capacitor C2 is connected to the ground.

  According to the present embodiment, even if the reference voltage Vr varies, the output of the first regulator 310 and the output of the second regulator 320 vary in phase, and therefore cancel each other in the oscillation circuit 20. In addition, fluctuation due to noise wraparound due to capacitive coupling between the power supply (terminal Vcc) and the output of the first regulator 310, and noise due to capacitive coupling between the power supply (terminal Vcc) and the output of the second regulator 320 are generated. Since the fluctuation due to the wraparound is also in phase, the oscillation circuit 20 cancels each other. Therefore, it is possible to realize the oscillator 1 that can reduce frequency fluctuations.

1-2. Second Embodiment FIG. 3 is a functional block diagram of an oscillator 1a according to a second embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The first noise attenuation circuit 31 of the oscillator 1a includes a filter 312. Further, the second noise attenuation circuit 32 of the oscillator 1 a is configured by a filter 322. As the filter 312 and the filter 322, for example, various known filters such as a high-pass filter, a low-pass filter, a band-pass filter, and a band elimination filter can be adopted.

  According to the present embodiment, it is possible to realize the oscillator 1a that can reduce frequency fluctuations with a simple configuration. Moreover, the same effect is produced for the same reason as in the first embodiment.

1-3. Third Embodiment FIG. 4 is a functional block diagram of an oscillator 1b according to a third embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The oscillator 1b of this embodiment further includes a control voltage generation circuit 40 that generates a control voltage Vc for controlling the oscillation frequency of the oscillation circuit 20. The control voltage generation circuit 40 generates a control voltage Vc based on the control signal input from the terminal Ctrl and outputs the control voltage Vc to the control node 23 of the oscillation circuit 20. The oscillation circuit 20 oscillates the vibrator 10 at a frequency corresponding to the control voltage Vc output from the control voltage generation circuit 40.

  The control voltage generation circuit 40 may be an analog circuit, a digital circuit, or a combination thereof. For example, the control voltage generation circuit 40 may include a digital-analog conversion circuit that converts a digital control signal into analog. Further, for example, the control voltage generation circuit 40 may include an amplifier circuit that amplifies or attenuates an analog control signal.

  A third power supply node 43 that is a power supply node on the high potential side of the control voltage generation circuit 40 is connected to the first power supply node 21 of the circuit 20 for oscillation. The fourth power supply node 44, which is the low potential side power supply node of the control voltage generation circuit 40, is connected to the second power supply node 22 of the oscillation circuit 20.

  According to this embodiment, since the control voltage Vc varies in phase with the variation of the power supply, the oscillation circuit 20 cancels each other. Therefore, it is possible to realize the oscillator 1b that can reduce the variation in frequency. Moreover, the same effect is produced for the same reason as in the first embodiment.

1-4. Fourth Embodiment FIG. 5 is a functional block diagram of an oscillator 1c according to a fourth embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The oscillator 1c according to the present embodiment further includes a temperature compensation circuit 50. The temperature compensation circuit 50 generates a correction voltage Vcmp for compensating the frequency temperature characteristic of the vibrator 10 and outputs the correction voltage Vcmp to the control node 24 of the oscillation circuit 20. The oscillation circuit 20 oscillates the vibrator 10 at a frequency corresponding to the correction voltage Vcmp output from the temperature compensation circuit 50.

  According to the present embodiment, since the frequency temperature characteristic of the vibrator 10 is compensated, it is possible to realize the oscillator 1c that can reduce the fluctuation of the frequency.

  The oscillator 1c according to the present embodiment further includes a heating element 60 and a temperature control circuit 80.

  The heating element 60 emits heat under the control of the temperature control circuit 80. As the heating element 60, for example, an element (such as a power transistor or a resistor) that generates heat when an electric current is passed can be used.

  According to the present embodiment, since the temperature of the vibrator 10 and the oscillation circuit 20 can be easily maintained at a desired temperature, it is possible to realize the oscillator 1c that can reduce the variation in frequency.

  The oscillator 1c of the present embodiment is configured to further include a temperature sensitive element 70. The temperature sensing element 70 detects the temperature around the vibrator 10. In the present embodiment, the temperature sensitive element 70 is disposed near the vibrator 10.

  As the temperature sensing element 70, for example, a thermistor (NTC thermistor (Negative Temperature Coefficient), PTC (Positive Temperature Coefficient) thermistor, etc.), a platinum resistor, a diode utilizing a forward voltage temperature dependency, or the like may be used. it can.

  Further, the temperature compensation circuit 50 generates the correction voltage Vcmp based on the temperature detected by the temperature sensing element 70. Further, the temperature control circuit 80 controls the heating element 60 so that the temperature of the vibrator 10 becomes constant based on the temperature detected by the temperature sensing element 70.

  According to the present embodiment, since the temperature of the vibrator 10 and the oscillation circuit 20 can be detected, the temperature compensation circuit 50 and the heating element 60 can be appropriately controlled. Therefore, it is possible to realize the oscillator 1c that can reduce the variation in frequency.

  Also in this embodiment, the same effect is obtained for the same reason as in the first embodiment.

2. Electronic Device FIG. 6 is a functional block diagram of an electronic device 500 according to this embodiment. In addition, the same code | symbol is attached | subjected to the structure similar to each embodiment mentioned above, and detailed description is abbreviate | omitted.

  An electronic device 500 according to this embodiment is an electronic device 500 including the oscillator 1. In the example illustrated in FIG. 6, the electronic device 500 includes an oscillator 1, a multiplication circuit 510, a CPU (Central Processing Unit) 520, an operation unit 530, a ROM (Read Only Memory) 540, a RAM (Random Access Memory) 550, and a communication unit. 560, a display unit 570, and a sound output unit 580. Note that the electronic apparatus 500 according to the present embodiment may be configured such that some of the components (each unit) illustrated in FIG. 6 are omitted or changed, or other components are added.

The multiplier circuit 510 supplies a clock pulse not only to the CPU 520 but also to each unit (not shown). The clock pulse may be, for example, a signal obtained by extracting a desired harmonic signal from the oscillation signal from the oscillator 1 by the multiplication circuit 510, or the oscillation signal from the oscillator 1 is multiplied by the multiplication circuit 510 having a PLL synthesizer. It may be a signal (not shown).

  The CPU 520 performs various types of calculation processing and control processing using the clock pulse output from the multiplication circuit 510 in accordance with a program stored in the ROM 540 or 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 displays various types of information on the display unit 570. Processing for transmitting a display signal, processing for 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, data, and the like 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 the external device.

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

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

  Since the electronic device 500 according to the present embodiment includes the oscillator 1 that can reduce frequency fluctuations, the electronic device 500 with high operational reliability can be realized.

  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, ink jet ejection devices (for example, ink jet printers), routers, switches, etc. Storage area network devices, local area network devices, mobile terminal base station devices, televisions, video cameras, video recorders, car navigation devices, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, electronic games Equipment, game controllers, word processors, workstations, videophones, security TV monitors, electronic binoculars, POS (point of sale) terminals, medical equipment (eg Electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring instruments, instruments (eg, vehicle, aircraft, ship instruments), flight simulator , Head mounted display, motion trace, motion tracking, motion controller, PDR (pedestrian position direction measurement) and the like.

  FIG. 7 is a diagram illustrating an example of the appearance of a smartphone that is an example of the electronic apparatus 500. A smartphone that is the electronic device 500 includes a button as the operation unit 530 and an LCD as the display unit 570. And since the smart phone which is the electronic device 500 is provided with the oscillator 1 which can reduce the fluctuation | variation of a frequency, the electronic device 500 with high operation | movement reliability is realizable.

3. FIG. 8 is a diagram (top view) illustrating an example of the moving object 400 according to the present embodiment. In addition, the same code | symbol is attached | subjected to the structure similar to each embodiment mentioned above, and detailed description is abbreviate | omitted.

  The moving body 400 according to the present embodiment is a moving body 400 including the oscillator 1. In the example illustrated in FIG. 8, the moving object 400 includes a controller 420 that performs various controls such as an engine system, a brake system, and a keyless entry system, a controller 430, a controller 440, a battery 450, and a backup battery 460. ing. Note that the moving body 400 according to the present embodiment may be configured such that some of the components (each unit) illustrated in FIG. 8 are omitted or changed, or other components may be added.

  Since the moving body 400 according to the present embodiment includes the oscillator 1 that can reduce frequency fluctuations, the moving body 400 with high operation reliability can be realized.

  As such a moving body 400, various moving bodies can be considered, and examples thereof include automobiles (including electric automobiles), aircraft such as jets and helicopters, ships, rockets, and artificial satellites.

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

  The above-described embodiments and modifications are merely examples, and the present invention is not limited to these. For example, it is possible to appropriately combine each embodiment and each modification.

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

DESCRIPTION OF SYMBOLS 1,1a, 1b, 1c ... Oscillator, 10 ... Oscillator, 20 ... Circuit for oscillation, 21 ... First power supply node, 22 ... Second power supply node, 23 ... Control node, 24 ... Control node, 31 ... First noise Attenuation circuit 32 ... second noise attenuation circuit 40 ... control voltage generation circuit 43 ... third power supply node 44 ... fourth power supply node 50 ... temperature compensation circuit 60 ... heating element 70 ... temperature sensing element 80 ... Temperature control circuit, 310 ... first regulator, 312 ... filter, 320 ... second regulator, 322 ... filter, 330 ... reference voltage generation circuit, 400 ... moving body, 410 ... oscillator, 420,430,440 ... controller, 450 ... Battery, 460 ... Backup battery, 500 ... Electronic device, 510 ... Multiplier circuit, 520 ... CPU, 530 ... Operation unit, 540 ... ROM, 550 RAM, 560 ... communication unit, 570 ... display unit, 580 ... sound output unit, A1, A2 ... amplifier circuit, C1, C2 ... capacitor, M1, M2 ... PMOS transistor, OUT ... output terminal, R11, R12, R21, R22 …resistance

Claims (9)

A vibrator,
An oscillation circuit for resonating the vibrator and outputting an oscillation signal;
A first noise attenuation circuit disposed on a signal path between a high potential side of a power supply and a first power supply node that is a power supply node on the high potential side of the oscillation circuit;
A second noise attenuation circuit disposed on a signal path between a high potential side of the power supply and a second power supply node which is a power supply node on the low potential side of the oscillation circuit;
Including an oscillator. The oscillator according to claim 1, wherein
The first noise attenuation circuit is a first regulator that generates a voltage based on a reference voltage;
The second noise attenuation circuit is an oscillator that is a second regulator that generates a voltage based on the reference voltage. The oscillator according to claim 1, wherein
The oscillator in which the first noise attenuation circuit and the second noise attenuation circuit are filters. The oscillator according to any one of claims 1 to 3,
A control voltage generation circuit for generating a control voltage for controlling the oscillation frequency of the oscillation circuit;
A third power supply node that is a power supply node on the high potential side of the control voltage generation circuit is connected to the first power supply node,
A fourth power supply node, which is a power supply node on the low potential side of the control voltage generation circuit, is connected to the second power supply node. The oscillator according to any one of claims 1 to 4,
An oscillator further comprising a temperature compensation circuit for compensating a frequency temperature characteristic of the vibrator. The oscillator according to any one of claims 1 to 5,
An oscillator further comprising a heating element. The oscillator according to claim 5 or 6,
An oscillator further including a temperature sensitive element.   An electronic apparatus comprising the oscillator according to claim 1.   A moving body comprising the oscillator according to claim 1.

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