Oscillator

Abstract

To provide an oscillation device capable of reducing acceleration sensitivity and phase noise.SOLUTION: An oscillation device 1 of the invention includes a first crystal oscillator 100, a driver circuit 101, a first buffer 102, an attenuator 103, a second crystal oscillator 104, and a second buffer 105. The first crystal oscillator 100 has a first resonant frequency and the second crystal oscillator 104 has a second resonant frequency. The driver circuit 101 generates a first oscillation signal O1 having the first resonant frequency by driving the first crystal oscillator 100. The first buffer 102 generates a first clock signal C1 according to the first oscillation signal. The attenuator 103 generates an attenuated signal A by attenuating the waveform amplitude of the first clock signal C1. The second crystal oscillator 104 generates a second oscillation signal O2 having the second resonant frequency by rectifying the attenuated signal A. The second buffer 105 generates a second clock signal C2 according to the second oscillation signal O2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an oscillation device, and more particularly to an oscillation device having reduced acceleration sensitivity and phase noise.

Background Art

[0002] Electronic devices often include an oscillator that provides an oscillation signal used as a clock source. The oscillation signal is controlled by a resonator that requires some form of excitation signal to sustain the oscillation.

[0003] The operation of an oscillator controlled by a resonator can be affected by the number of years of use, temperature, and particularly specific environmental conditions such as acceleration here. When acceleration is applied to the oscillator, the frequency of the oscillation signal may change. The change in frequency is proportional to the magnitude of the acceleration and depends on the direction that produces the vector of acceleration sensitivity. Acceleration due to temporal changes such as vibration may cause frequency modulation of the frequency of the oscillator. Therefore, in order to generate a stable and pure frequency output from the oscillator, it is desirable to reduce the sensitivity of such an oscillator to frequency changes due to acceleration.

[0004] In order to solve the above-described problems of the prior art, the present invention provides an oscillation device.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides an oscillation device that reduces acceleration sensitivity and phase noise.

Means for Solving the Problems

[0006] In one embodiment of the present invention, the oscillation device includes a first crystal oscillator, a drive circuit, a first buffer, an attenuator, a second crystal oscillator, and a second buffer. The first crystal oscillator has a first resonance frequency, and the second crystal oscillator has a second resonance frequency. The drive circuit is coupled to the first crystal oscillator. The drive circuit is configured to drive the first crystal oscillator to generate a first oscillation signal having the first resonance frequency. The first buffer is coupled to the drive circuit and the first crystal oscillator and is configured to receive the first oscillation signal. The first buffer is configured to isolate from load fluctuations at the subsequent stage of the first crystal oscillator and the drive circuit and generate a first clock signal in response to the first oscillation signal. The attenuator is coupled to the first buffer and is configured to receive the first clock signal. The attenuator is configured to reduce the amplitude of the waveform of the first clock signal to generate an attenuated signal. The second crystal oscillator is coupled to the attenuator and is configured to receive and rectify the attenuated signal to generate a second oscillation signal having the second resonance frequency. The second buffer is coupled to the second crystal oscillator and is configured to receive the second oscillation signal. The second buffer is configured to isolate from load fluctuations at the subsequent stage of the first crystal oscillator, the drive circuit, the attenuator, and the second crystal oscillator and generate a second clock signal in response to the second oscillation signal.

[0007] In one embodiment of the present invention, the drive circuit and the first buffer are integrated into an integrated circuit (IC), and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0008] In one embodiment of the present invention, the drive circuit, the first buffer, and the second buffer are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0009] In one embodiment of the present invention, the drive circuit is integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0010] In one embodiment of the present invention, the drive circuit and the second buffer are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0011] In one embodiment of the present invention, the drive circuit, the first buffer, and the attenuator are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0012] In one embodiment of the present invention, the drive circuit, the first buffer, the second buffer, and the attenuator are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0013] In one embodiment of the present invention, the oscillation device further includes an electrical switch, one end of the electrical switch is coupled to the first buffer, and the other end is coupled to the attenuator or the output terminal.

[0014] In one embodiment of the present invention, the drive circuit, the first buffer, the second buffer, the attenuator, and the electrical switch are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0015] In one embodiment of the present invention, the drive circuit, the first buffer, the attenuator, and the electrical switch are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

[0016] In one embodiment of the present invention, the drive circuit, the first buffer, and the electrical switch are integrated into an IC, and the IC and the first crystal oscillator are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO).

Advantages of the Invention

[0017] That is, the oscillation device filters the oscillation signal to generate a clock signal with two crystal oscillators, thereby reducing the acceleration sensitivity and the phase noise.

Brief Description of the Drawings

[0018]

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Modes for Carrying Out the Invention

[0019] Regarding the embodiments of the present invention, further explanations will be given below in conjunction with the relevant diagrams. In the drawings and the specification, the same or similar members are denoted by the same reference numerals as much as possible. In the drawings, for the sake of simplicity and convenience, the shape and thickness may be shown enlarged. This description relates in particular to elements that form part of the method and apparatus according to the present invention, or elements that cooperate more directly with the method and apparatus according to the present invention. Elements not particularly shown in the figures or described in the specification can be construed as being in forms known to those skilled in the art. Various changes and modifications will be apparent to those skilled in the art upon understanding the content of the present invention.

[0020] Unless otherwise specified, some conditional clauses or auxiliary words, such as "can", "could", "might", or "may", usually represent embodiments of the present invention, but may also be interpreted as features, components, or steps that may not be necessary. In other embodiments, these features, components, or steps may not be necessary.

[0021] The description of "one embodiment" or "an embodiment" in the text refers to specific elements, structures, or features related within at least one embodiment. Therefore, multiple descriptions of "one embodiment" or "an embodiment" in many places in the text are not necessarily for the same embodiment. Furthermore, specific components, structures, and features in one or more embodiments can be combined based on an appropriate method.

[0022] Specific terms are used in the specification and claims to refer to specific components, but those skilled in the art should understand that the components may be referred to by different names. The present disclosure does not intend to distinguish components with different names but the same functions. The term "comprising" in the present specification and claims is used in an open-ended form, that is, it is not intended to be limited to what is listed. Also, terms such as "coupled", "coupling", and "coupled to" include any direct and indirect connections. Therefore, when there is a description in the present disclosure that a first device is coupled to a second device, it indicates that the first device may be directly or indirectly connected to the second device, with or without other intermediate devices or connection means, via electrical connection, wireless communication, optical communication, or other signal connections.

[0023] In particular, the embodiments described below are merely illustrative. Those skilled in the art will readily understand that many modifications and changes can be made to the apparatus and method while maintaining the teachings of the invention. Therefore, the following disclosure should be construed as being limited only by the appended claims. Unless otherwise clearly stated throughout the patent application and claims, "one" and "said" include the meaning of "one or at least one" of the element or component. Further, throughout the patent application and claims, unless the context clearly excludes a plurality, a singular article also includes a description of a plurality of elements or components. The meaning of each term used in the claims and specification of this patent refers to the ordinary meaning known to those skilled in the art, unless additional annotations of the meaning are provided. Some of the terms used to explain the invention are discussed to guide those practicing the art of the invention. All examples in this specification do not limit the scope of the claims of the invention.

[0024] In the following description, an oscillation device is provided. This oscillation device filters an oscillation signal and generates a clock signal with two crystal oscillators, thereby reducing acceleration sensitivity and phase noise.

[0025] FIG. 1 is a diagram showing an oscillation device according to a first embodiment of the present invention. Referring to FIG. 1, the oscillation device 1 includes a first crystal oscillator 100, a drive circuit 101, a first buffer 102, an attenuator 103, a second crystal oscillator 104, and a second buffer 105. The first crystal oscillator 100 has a first resonance frequency. The second crystal oscillator 104 has a second resonance frequency. The first resonance frequency may be different from the second resonance frequency. It is desirable that the first resonance frequency be of the same order as the second resonance frequency. Here, the first crystal oscillator 100 and the second crystal oscillator 104 have the same resonance frequency without using a feedback circuit. The drive circuit 101 is coupled to the first crystal oscillator 100. The first buffer 102 is coupled to the drive circuit 101 and the first crystal oscillator 100. The attenuator 103 is coupled to the first buffer 102. The second crystal oscillator 104 is coupled to the attenuator 103. The second buffer 105 is coupled to the second crystal oscillator 104.

[0026] In the operation of the oscillation device 1, the drive circuit 101 drives the first crystal oscillator 100 to generate a first oscillation signal О1 having a first resonance frequency. The first buffer 102 receives the first oscillation signal О1. The first buffer 102 isolates the first crystal oscillator 100 and the load variation in the subsequent stage of the drive circuit 101, and generates a first clock signal C1 according to the first oscillation signal О1. The attenuator 103 receives the first clock signal C1. The attenuator 103 reduces the amplitude of the waveform of the first clock signal C1 to generate an attenuated signal A. The second crystal oscillator 104 receives and rectifies the attenuated signal A to generate a second oscillation signal О2 having a second resonance frequency. The second buffer 105 receives the second oscillation signal О2. The second buffer 105 isolates the first crystal oscillator 100, the drive circuit 101, the attenuator 103, and the load variation in the subsequent stage of the second crystal oscillator 104, and generates a second clock signal C2 according to the second oscillation signal О2.

[0027] FIG. 2 is a diagram showing the acceleration (g) sensitivity characteristics in the embodiment of the present invention. FIG. 3 is a diagram showing the phase noise characteristics in the embodiment of the present invention. Referring to FIGS. 1, 2, and 3, the parameters in FIGS. 2 and 3 are defined by Equation 1 and Equation 2.

[0028]

Equation

[0029]

Equation

[0030] i represents the position of the oscillation device 1. Γ i represents the acceleration sensitivity of i. Γ x is in the x direction of Γ i represents the acceleration sensitivity. Γ y is in the y direction of Γ i represents the acceleration sensitivity. Γ z is in the z direction of Γ i represents the acceleration sensitivity in the z direction.

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[0031] FIG. 4 is a diagram showing an oscillation device according to a second embodiment of the present invention. Referring to FIGS. 1 and 4, the drive circuit 101 and the first buffer 102 may be integrated into the IC10. The IC10 and the first crystal oscillator 100 may be integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0032] FIG. 5 is a diagram showing an oscillation device according to a third embodiment of the present invention. Referring to FIGS. 1 and 5, the drive circuit 101, the first buffer 102, and the second buffer 105 may be integrated into the IC10. The IC10 and the first crystal oscillator 100 may be integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0033] FIG. 6 is a diagram showing an oscillation device according to a fourth embodiment of the present invention. Referring to FIGS. 1 and 6, the drive circuit 101 may be integrated into the IC 10. The IC 10 and the first crystal oscillator 100 are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0034] FIG. 7 is a diagram showing an oscillation device according to a fifth embodiment of the present invention. Referring to FIGS. 1 and 7, the drive circuit 101 and the second buffer 105 may be integrated into the IC 10. The IC 10 and the first crystal oscillator 100 are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0035] FIG. 8 is a diagram showing an oscillation device according to a sixth embodiment of the present invention. Referring to FIGS. 1 and 8, the drive circuit 101, the first buffer 102, and the attenuator 103 may be integrated into the IC 10. The IC 10 and the first crystal oscillator 100 are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0036] FIG. 9 is a diagram showing an oscillation device according to a seventh embodiment of the present invention. Referring to FIGS. 1 and 9, the drive circuit 101, the first buffer 102, the second buffer 105, and the attenuator 103 may be integrated into the IC 10. The IC 10 and the first crystal oscillator 100 are integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0037] FIG. 10 is a diagram showing an oscillation device according to an eighth embodiment of the present invention. Referring to FIGS. 1 and 10, unlike the first embodiment, the eighth embodiment further includes an electric switch 106. One end of the electric switch 106 is coupled to the first buffer 102, and the other end is coupled to the attenuator 103 or the output terminal 107. The second buffer 105 is coupled to the output terminal 107. When the electric switch 106 connects the first buffer 102 to the attenuator 103 and disconnects the first buffer 102 from the connection with the output terminal 107, the attenuator 103 receives the first clock signal C1 via the electric switch 106 so as to generate the second clock signal C2 received by the second buffer 105 from the output terminal 107. When the electric switch 106 disconnects the first buffer 102 from the connection with the attenuator 103 and connects the first buffer 102 to the output terminal 107, the first buffer 102 transmits the first clock signal C1 to the output terminal 107 via the electric switch 106.

[0038] FIG. 11 is a diagram showing an oscillation device according to a ninth embodiment of the present invention. Referring to FIGS. 10 and 11, the drive circuit 101, the first buffer 102, the second buffer 105, the attenuator 103, and the electric switch 106 may be integrated into the IC10. The IC10 and the first crystal oscillator 100 may be integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0039] FIG. 12 is a diagram showing an oscillation device according to a tenth embodiment of the present invention. Referring to FIGS. 10 and 12, the drive circuit 101, the first buffer 102, the attenuator 103, and the electric switch 106 may be integrated into the IC10. The IC10 and the first crystal oscillator 100 may be integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0040] FIG. 13 is a diagram showing an oscillation device according to the 11th embodiment of the present invention. Referring to FIGS. 10 and 13, the drive circuit 101, the first buffer 102, and the electric switch 106 may be integrated into the IC10. The IC10 and the first crystal oscillator 100 may be integrated into a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), but the present invention is not limited thereto.

[0041] According to the above embodiment, the oscillation device of the present invention filters the oscillation signal to generate a clock signal with two crystal oscillators, thereby reducing the acceleration sensitivity and phase noise.

[0042] The above embodiments are merely illustrative of the present invention and do not limit the scope of the present invention. Therefore, equivalent modifications or changes based on the shape, structure, features, or spirit disclosed by the present invention are included within the scope of the claims of the present invention.

Explanation of Signs

[0043] 1 Oscillation device 10 IC 100 First crystal oscillator 101 Drive circuit 102 First buffer 103 Attenuator 104 Second crystal oscillator 105 Second buffer 106 Electric switch 107 Output terminal A Attenuated signal C1 First clock signal C2 Second clock signal O1 First oscillation signal O2 Second oscillation signal

Claims

1. a first crystal oscillator having a first resonance frequency and a drive circuit coupled to the first crystal oscillator, the drive circuit driving the first crystal oscillator to generate a first oscillation signal having the first resonance frequency; a first buffer coupled to the drive circuit and the first crystal oscillator and configured to receive the first oscillation signal, the first buffer being configured to isolate from load variations subsequent to the first crystal oscillator and the drive circuit and generate a first clock signal in response to the first oscillation signal; an attenuator coupled to the first buffer and configured to receive the first clock signal, the attenuator being configured to reduce the amplitude of the waveform of the first clock signal to generate an attenuated signal; a second crystal oscillator having a second resonance frequency, coupled to the attenuator, and configured to receive the attenuated signal and generate a second oscillation signal having the second resonance frequency; a second buffer coupled to the second crystal oscillator and configured to receive the second oscillation signal, the second buffer being configured to isolate from load variations subsequent to the first crystal oscillator, the drive circuit, the attenuator, and the second crystal oscillator and generate a second clock signal in response to the second oscillation signal; An oscillation device comprising.

2. The drive circuit and the first buffer are integrated in an integrated circuit (IC), and the integrated circuit and the first crystal oscillator are mounted on a crystal oscillator (XO: crystal oscillator), a temperature-compensated crystal oscillator (TCXO: Temperature Compensated Crystal Oscillator), a voltage-controlled crystal oscillator (VCXO: Voltage Controlled Crystal Oscillator), an oven-controlled crystal oscillator (OCXO: Oven Controlled Crystal Oscillator), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO: Voltage Controlled Temperature Compensated Crystal Oscillator), the oscillation device according to claim 1.

3. The drive circuit, the first buffer, and the second buffer are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 1.

4. The drive circuit is integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 1.

5. The drive circuit and the second buffer are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), an oven-controlled crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 1.

6. The drive circuit, the first buffer, and the attenuator are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 1.

7. The drive circuit, the first buffer, the second buffer, and the attenuator are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 1.

8. Further including an electric switch, the electric switch switching the output of the first buffer to the input or output terminal of the attenuator, the oscillation device according to claim 1.

9. The drive circuit, the first buffer, the second buffer, the attenuator, and the electric switch are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 8.

10. The drive circuit, the first buffer, the attenuator, and the electric switch are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), the oscillation device according to claim 8.

11. The drive circuit, the first buffer, and the electric switch are integrated in an IC, and the IC and the first crystal oscillator are mounted on a crystal oscillator (XO), a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), a thermostatic chamber type crystal oscillator (OCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO). The oscillation device according to claim 8.

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