Crystal oscillation circuit, method and electronic device

Abstract

Embodiments of the present invention relate to the field of circuit design, and in particular to a crystal oscillator circuit, method, and electronic device. A crystal oscillator circuit is disclosed, comprising: an excitation signal generator for generating an excitation signal after a crystal oscillator is enabled, and inputting the excitation signal into a broadband modulator; a broadband modulator for modulating the excitation signal to generate a modulation signal, and inputting the modulation signal into a crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range; an oscillation amplitude detector for detecting the amplitude of the output signal of the crystal oscillator, and if it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the broadband modulator stops inputting the modulation signal into the crystal oscillator. In the present invention, by shortening the start-up time of the crystal oscillator and reducing the average consumption of the circuit, rapid start-up, resource saving, and extended device service life are achieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of circuit design, and in particular to a crystal oscillator circuit, method and electronic equipment. Background Art

[0002] A crystal oscillator is a crystal element that is cut from a piece of quartz crystal at a certain azimuth angle (referred to as a wafer) and has an IC added inside the package to form an oscillation circuit. It is also referred to as a quartz crystal resonator, or simply a quartz crystal or crystal. Since quartz crystal has a very high quality factor, a quartz crystal oscillator can generate an oscillation waveform with an accurate and stable frequency, and is widely used in fields such as watches, military industry, and communications that require a high oscillation frequency.

[0003] In recent years, the design demand for low-power and low-cost integrated circuits in various fields has become increasingly prominent. The chip of the integrated circuit has two cycles of wake-up / sleep, and its built-in crystal oscillator will also follow the chip into the sleep / wake-up state. As a component that provides a time reference for the chip, the speed of the crystal oscillator's oscillation will directly affect the working efficiency of the chip, so among the multiple design indicators of the crystal oscillator circuit, the oscillation start-up time is particularly important. However, the inventors found that there are at least the following problems in the prior art: the commonly used crystal oscillators have the disadvantage of slow oscillation, and the oscillation start-up time is long, generally between a few milliseconds and tens of milliseconds, which wastes time; and in this process, the crystal oscillator only consumes power and cannot work, wasting resources, which results in the chip having to wait for the crystal oscillator to start before it can start working, thereby affecting the working efficiency of the chip. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a crystal oscillator circuit, method and electronic device, so as to shorten the start-up time of the crystal oscillator, reduce the average consumption of the circuit, achieve rapid start-up, save resources and extend the service life of the device.

[0005] To solve the above technical problems, an embodiment of the present invention provides a crystal oscillator circuit, comprising: a crystal oscillator, an excitation signal generator, a broadband modulator, and an oscillation amplitude detector; the excitation signal generator is connected to the broadband modulator, and the excitation signal generator is used to generate an excitation signal after the crystal oscillator is enabled, and input the excitation signal to the broadband modulator; the broadband modulator is connected to the excitation signal generator and the crystal oscillator respectively, and the broadband modulator is used to modulate the excitation signal to generate a modulation signal, and input the modulation signal to the crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range; the oscillation amplitude detector is connected to the crystal oscillator, and the oscillation amplitude detector is used to detect the amplitude of the output signal of the crystal oscillator. If it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator.

[0006] An embodiment of the present invention also provides a crystal oscillation method, comprising: after the crystal oscillator is enabled, an excitation signal generator generates an excitation signal and inputs the excitation signal into the broadband modulator; the broadband modulator modulates the excitation signal to generate a modulation signal, and inputs the modulation signal into the crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range; an oscillation amplitude detector detects the amplitude of the output signal of the crystal oscillator, and if it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the broadband modulator stops inputting the modulation signal into the crystal oscillator.

[0007] An embodiment of the present invention further provides an electronic device, comprising the above-mentioned crystal oscillator circuit.

[0008] Compared with the prior art, in the embodiments of the present invention, the excitation signal generator is used to generate the excitation signal, and the broadband modulator is used to modulate the excitation signal to generate the modulation signal. Since the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range, the modulation signal can more accurately excite the input end of the crystal oscillator, thereby shortening the start-up time of the crystal oscillator, reducing the average power consumption of the circuit, and saving time and resources; and the oscillation amplitude detector is used to detect the amplitude of the output signal of the crystal oscillator. When it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator, which can further reduce power consumption and extend the service life of the device.

[0009] In addition, if it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator, including: if it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the oscillation amplitude detector is used to send a first feedback signal to the excitation signal generator and / or the broadband modulator; the first feedback signal is used to control the excitation signal generator and / or the broadband modulator to stop signal output. By sending a first feedback signal to the excitation signal generator and / or the broadband modulator through the oscillation amplitude detector, and controlling the excitation signal generator and / or the broadband modulator to stop signal output, the broadband modulator can stop inputting the modulation signal to the crystal oscillator, thereby allowing the crystal oscillator to oscillate freely, reducing power consumption, and extending the service life of the device.

[0010] In addition, the crystal oscillator circuit further includes: a bias current controller, an amplifier, and an impedance stabilization controller; the bias current controller is connected to the crystal oscillator, and the bias current controller is used to input a bias current to the amplifier when the crystal oscillator is enabled; the amplifier is connected to the crystal oscillator, and the amplifier is used to amplify the bias current when the crystal oscillator is enabled, and input the amplified bias current to the crystal oscillator; the impedance stabilization controller is connected to the crystal oscillator, and the impedance stabilization controller is used to provide impedance to the crystal oscillator when the crystal oscillator is enabled. Inputting the bias current amplified by the amplifier into the crystal oscillator increases the current input amount of the crystal oscillator, and using the impedance stabilization controller to provide impedance can further speed up the starting speed of the crystal oscillator.

[0011] In addition, the oscillation amplitude detector is also used to send a second feedback signal to the bias current controller when it detects that the amplitude of the output signal of the crystal oscillator increases; the second feedback signal is used to control the bias current controller to reduce the bias current input to the amplifier. After the crystal oscillator starts oscillating, when the oscillation amplitude detector detects that the amplitude of the output signal of the crystal oscillator increases, the second feedback signal is sent to control the bias current controller to reduce the input bias current, thereby reducing the bias current input to the crystal oscillator, so that the amplitude of the signal of the crystal oscillator remains stable, and the crystal oscillator operates stably.

[0012] In addition, the impedance stabilization controller is also used to keep the impedance provided to the crystal oscillator unchanged when the bias current controller reduces the bias current input to the amplifier. The impedance stabilization controller always keeps the impedance of the oscillation node of the crystal oscillator stable, thereby ensuring that the frequency of the crystal oscillator always remains stable during the process of the bias current controller reducing the current input to the crystal oscillator, further ensuring the stable operation of the crystal oscillator.

[0013] In addition, the excitation signal generator is a ring oscillator, which has a simple circuit, is easy to start oscillation, and is easy to integrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0015] Figure 1 is a circuit device schematic diagram of a crystal oscillator circuit according to a first embodiment of the present invention;

[0016] Figure 2 is a circuit device schematic diagram of a crystal oscillator circuit according to a second embodiment of the present invention;

[0017] Figure 3 is a flow chart of a crystal oscillation method according to the third embodiment of the present invention. DETAILED DESCRIPTION

[0018] To make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present invention, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can be implemented. The division of the following embodiments is for the convenience of description, and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined and referenced with each other without contradiction.

[0019] The first embodiment of the present invention relates to a crystal oscillator circuit, which can be specifically applied to electronic devices. In this embodiment, an excitation signal generator is connected to a broadband modulator, and is used to generate an excitation signal after the crystal oscillator is enabled; the broadband modulator is respectively connected to the excitation signal generator and the crystal oscillator, and is used to modulate the excitation signal to generate a modulation signal, and input the modulation signal to the crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range; the oscillation amplitude detector is connected to the crystal oscillator, and is used to detect the amplitude of the output signal of the crystal oscillator, and if it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator.

[0020] The implementation details of a crystal oscillator circuit of the first embodiment are specifically described below. The following content is only provided for easy understanding of the implementation details and is not necessary for implementing this method.

[0021] A schematic diagram of a circuit device of a crystal oscillator circuit in this embodiment is shown in FIG. Figure 1 As shown, the following devices are specifically included: an excitation signal generator 101 , a broadband modulator 102 , a crystal oscillator 103 , and an oscillation amplitude detector 104 .

[0022] The excitation signal generator 101 is connected to the broadband modulator 102 . The excitation signal generator 101 is used to generate an excitation signal after the crystal oscillator 103 is enabled, and input the excitation signal to the broadband modulator 102 .

[0023] Specifically, enable is an "enable" signal, and feed enable is a signal that allows feeding, that is, the crystal oscillator 103 can only be started when the feed enable signal is valid. After the crystal oscillator 103 is enabled, the excitation signal generator 101 generates an excitation signal and inputs the excitation signal to the broadband modulator 102.

[0024] In a specific example, the excitation signal generator 101 is a ring oscillator. A ring oscillator is a machine formed by connecting the output and input ends of three or more odd-numbered NOT gates end to end to form a ring; the characteristics of a ring oscillator are simple circuits, easy oscillation, and no resistance and capacitance components are required without a delay network, which is easy to integrate.

[0025] The broadband modulator 102 is connected to the excitation signal generator 101 and the crystal oscillator 103 respectively. The broadband modulator 102 is used to modulate the excitation signal to generate a modulation signal, and input the modulation signal to the crystal oscillator 103 .

[0026] Specifically, since the frequency fosc of the excitation signal generated by the mass-produced excitation signal generator 101 of the manufacturer is not the same, it cannot be guaranteed that the frequency fosc of the excitation signal is within the error range of the frequency fc required by the crystal oscillator 103, it is necessary to use the broadband modulator 102 to modulate the excitation signal to generate a modulation signal, so that the frequency of the generated modulation signal is close to the frequency of the crystal oscillator 103, that is, the difference between the frequency fosc' of the modulation signal and the frequency fc of the crystal oscillator is within the preset range, fosc'-fc∈(-δ, +δ), this preset range is the allowable error range of the frequency fc required by the crystal oscillator 103, so that the crystal oscillator will have a better acceleration start-up effect. For example: when the difference between the frequency of the general signal and the frequency of the crystal oscillator is within the range of (-0.5%, +0.5%), the crystal oscillator will have a better acceleration start-up effect. In a crystal oscillator circuit, the difference between the frequency fosc of the excitation signal and the frequency fc required by the crystal oscillator 103 is 1%, which is not within the error range. The wideband modulator 102 is used to modulate the excitation signal to generate a modulation signal. The difference between the frequency fosc' of the modulation signal and the frequency fc of the crystal oscillator is 0.2%, which is within the error range, and the purpose of rapid start-up of the crystal oscillator can be achieved.

[0027] The oscillation amplitude detector 104 is connected to the crystal oscillator 103 and is used to detect the amplitude of the output signal of the crystal oscillator 103. If it is detected that the amplitude of the output signal of the crystal oscillator 103 exceeds a preset amplitude value, the broadband modulator 102 stops inputting the modulation signal to the crystal oscillator 103.

[0028] Specifically, the preset amplitude value can be set according to actual needs, and this embodiment does not make specific limitations. In this embodiment, if the oscillation amplitude detector 104 detects that the amplitude of the output signal of the crystal oscillator 103 exceeds the preset amplitude value, the oscillation amplitude detector 104 is used to send a first feedback signal to the excitation signal generator 101, and the first feedback signal controls the excitation signal generator 101 to stop signal output, that is, no signal is connected to the input end of the broadband modulator 102, so that the broadband modulator can stop inputting the modulation signal to the crystal oscillator 103.

[0029] In a specific example, if the oscillation amplitude detector 104 detects that the amplitude of the output signal of the crystal oscillator 103 exceeds a preset amplitude value, the oscillation amplitude detector 104 is used to send a first feedback signal to the broadband modulator 102, and the first feedback signal controls the broadband modulator 102 to stop signal output, so that the broadband modulator stops inputting the modulation signal to the crystal oscillator 103.

[0030] In a specific example, when the oscillation amplitude detector 104 detects that the amplitude of the output signal of the crystal oscillator 103 exceeds the preset amplitude value, the oscillation amplitude detector 104 is used to send a first feedback signal to the excitation signal generator 101 and the broadband modulator 102. The first feedback signal controls the excitation signal generator 101 and the broadband modulator 102 to stop signal output, and the broadband modulator 102 stops inputting the modulation signal to the crystal oscillator 103. In this way, when the excitation signal generator 101 fails and cannot receive the first feedback signal sent by the oscillation amplitude detector 104, the broadband modulator 102 can still receive the first feedback signal; or when the broadband modulator 102 fails and cannot receive the first feedback signal sent by the oscillation amplitude detector 104, the excitation signal generator 101 can still receive the first feedback signal. That is, when one of the devices fails, another device can receive the first feedback signal, which has double protection and enables the broadband modulator to stop inputting the modulation signal to the crystal oscillator 103.

[0031] Compared with the traditional crystal oscillator circuit, this embodiment takes into account that the mass-produced excitation signal generator cannot guarantee that the frequency of the generated excitation signal is within the error range of the frequency required by the crystal oscillator. The excitation signal is modulated by a broadband modulator to generate a modulation signal, so that the difference between the frequency of the modulation signal and the frequency of the crystal oscillator can be within a preset range. In this way, the broadband modulator inputs the modulation signal into the crystal oscillator, which can make the crystal oscillator have a better accelerated oscillation effect, achieve the purpose of rapid oscillation, reduce the average power consumption of the circuit, and save time and resources. In addition, the oscillation amplitude detector is used to detect the amplitude of the output signal of the crystal oscillator. If it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator, which can further reduce power consumption and extend the service life of the device.

[0032] The second embodiment of the present invention relates to a crystal oscillator circuit. This embodiment is substantially the same as the first embodiment, except that: in this embodiment, the crystal oscillator circuit further includes: a bias current controller, an amplifier, and an impedance stabilization controller; the bias current controller is connected to the amplifier, and is used to input a bias current to the amplifier when the crystal oscillator is enabled; the amplifier is respectively connected to the bias current controller and the crystal oscillator, and is used to amplify the bias current when the crystal oscillator is enabled, and input the amplified bias current to the crystal oscillator; the impedance stabilization controller is connected to the crystal oscillator, and is used to provide impedance to the crystal oscillator when the crystal oscillator is enabled.

[0033] A schematic diagram of a circuit device of a crystal oscillator circuit in this embodiment is shown in FIG. Figure 2As shown, the following devices are specifically included: an excitation signal generator 201, a broadband modulator 202, a crystal oscillator 203, an oscillation amplitude detector 204, a bias current controller 205, an amplifier 206, and an impedance stabilization controller 207.

[0034] The excitation signal generator 201 , the broadband modulator 202 , the crystal oscillator 203 , and the oscillation amplitude detector 204 are similar to the excitation signal generator 101 , the broadband modulator 102 , the crystal oscillator 103 , and the oscillation amplitude detector 104 , respectively, and are not described in detail herein.

[0035] The bias current controller 205 is connected to the amplifier 206 and is used to input a bias current to the amplifier 206 when the crystal oscillator 203 is enabled.

[0036] The amplifier 206 is connected to the bias current controller 205 and the crystal oscillator 203 respectively, and is used to amplify the bias current when the crystal oscillator 203 is enabled, and input the amplified bias current into the crystal oscillator 203 .

[0037] The impedance stabilization controller 207 is connected to the crystal oscillator 203 and is used to provide impedance to the crystal oscillator 203 when the crystal oscillator 203 is enabled.

[0038] Specifically, when the crystal oscillator 203 is enabled, a special bias current controller 205 is added to provide a bias current. The bias current amplified by the amplifier 206 can provide the maximum bias current for the crystal oscillator 203, so that the crystal oscillator 203 works in the maximum bias current state to obtain the maximum transconductance gm within a reasonable range, thereby increasing the current input of the crystal oscillator 203. Transconductance gm refers to the ratio between the change value of the output current and the change value of the input voltage. In this embodiment, gm is the ratio between the change value of the output current of the bias current controller and the change value of the input voltage of the bias circuit. At the same time, the impedance stabilization controller 207 can be used to provide the crystal oscillator 203 with the maximum impedance r0 within a reasonable range, so that the amplification factor (amplification factor = gm*r0) is maximized, which can further accelerate the start-up speed of the crystal oscillator 203.

[0039] In a specific example, the oscillation amplitude detector 203 is also used to send a second feedback signal to the bias current controller 205 when detecting that the amplitude of the output signal of the crystal oscillator 203 increases; the second feedback signal is used to control the bias current controller 205 to reduce the bias current input to the amplifier 206. Specifically, the oscillation amplitude detector 203 and the bias current controller 205 form a loop, that is, an amplitude feedback control loop, which controls the bias current controller 205 to reduce the bias current input to the amplifier 206, thereby reducing the amplified bias current input to the crystal oscillator 203, so as to maintain the amplitude of the crystal oscillator 203 constant and enable the crystal oscillator 203 to operate stably.

[0040] In a specific example, the impedance stabilization controller 207 is also used to keep the impedance provided to the crystal oscillator 203 unchanged when the bias current controller 205 reduces the bias current input to the amplifier 206. When the bias current controller 205 is controlled to reduce the bias current input to the amplifier 206, the amplified bias current input to the crystal oscillator 203 will also be reduced. The impedance stabilization controller 207 controls the impedance provided by the crystal oscillator 203 to remain unchanged, so that the frequency of the crystal oscillator 203 can always remain stable, further ensuring the stable operation of the crystal oscillator 203.

[0041] In this embodiment, when the crystal oscillator is enabled, a special bias current controller and amplifier are added to provide the maximum bias current for the crystal oscillator, thereby increasing the current input of the crystal oscillator; and the added impedance stabilization controller can provide the crystal oscillator with the maximum impedance within a reasonable range, thereby maximizing the amplification factor and further accelerating the starting speed of the crystal oscillator.

[0042] A third embodiment of the present invention relates to a crystal oscillation method. Figure 3 As shown, including:

[0043] Step 301: After the crystal oscillator is enabled, the excitation signal generator generates an excitation signal and inputs the excitation signal into the broadband modulator.

[0044] Step 302: The broadband modulator modulates the excitation signal to generate a modulation signal, and inputs the modulation signal into a crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range.

[0045] Step 303: The oscillation amplitude detector detects the amplitude of the output signal of the crystal oscillator. If it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator.

[0046] In a specific example, if it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator, including: if it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the oscillation amplitude detector is used to send a first feedback signal to the excitation signal generator and / or the broadband modulator; the first feedback signal is used to control the excitation signal generator and / or the broadband modulator to stop signal output.

[0047] In a specific example, the crystal oscillation method further includes: when the crystal oscillator is enabled, the bias current controller inputs the bias current to the amplifier; the amplifier inputs the amplified bias current to the crystal oscillator; and the impedance stabilization controller provides impedance to the crystal oscillator.

[0048] In a specific example, when the oscillation amplitude detector detects that the amplitude of the output signal of the crystal oscillator increases, the oscillation amplitude detector sends a second feedback signal to the bias current controller; the second feedback signal controls the bias current controller to reduce the bias current input to the amplifier.

[0049] In one specific example, the impedance stabilization controller maintains a constant impedance provided to a crystal oscillator while the bias current controller reduces the bias current to the amplifier input.

[0050] A fourth embodiment of the present invention relates to an electronic device, comprising the crystal oscillator circuit according to the first or second embodiment.

[0051] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A crystal oscillator circuit, characterized in that: include: Crystal oscillator, excitation signal generator, broadband modulator, oscillation amplitude detector; The excitation signal generator is connected to the broadband modulator, and the excitation signal generator is used to generate an excitation signal after the crystal oscillator is enabled, and input the excitation signal into the broadband modulator; The broadband modulator is connected to the crystal oscillator, and is used to modulate the excitation signal to generate a modulation signal, and input the modulation signal into the crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range; The oscillation amplitude detector is connected to the crystal oscillator, and the oscillation amplitude detector is used to detect the amplitude of the output signal of the crystal oscillator. If it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator, including: If it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the oscillation amplitude detector is used to send a first feedback signal to the excitation signal generator and / or the broadband modulator; the first feedback signal is used to control the excitation signal generator and / or the broadband modulator to stop signal output; The excitation signal generator is a ring oscillator.

2. The crystal oscillator circuit according to claim 1, characterized in that: The crystal oscillator circuit also includes: a bias current controller, an amplifier, and an impedance stabilization controller; The bias current controller is connected to the amplifier, and the bias current controller is used to input a bias current to the amplifier when the crystal oscillator is enabled; The amplifier is connected to the crystal oscillator, and is used to amplify the bias current and input the amplified bias current into the crystal oscillator when the crystal oscillator is enabled; The impedance stabilization controller is connected to the crystal oscillator, and is used to provide impedance to the crystal oscillator when the crystal oscillator is enabled.

3. The crystal oscillator circuit according to claim 2, characterized in that: The oscillation amplitude detector is also used to send a second feedback signal to the bias current controller when detecting that the amplitude of the output signal of the crystal oscillator increases; the second feedback signal is used to control the bias current controller to reduce the bias current input to the amplifier.

4. The crystal oscillator circuit according to claim 3, characterized in that: The impedance stabilization controller is further configured to keep the impedance provided to the crystal oscillator unchanged when the bias current controller reduces the bias current input to the amplifier.

5. A crystal oscillation method, characterized in that: include: After the crystal oscillator is enabled, the excitation signal generator generates an excitation signal and inputs the excitation signal into the broadband modulator; The broadband modulator modulates the excitation signal to generate a modulation signal, and inputs the modulation signal into the crystal oscillator, wherein the difference between the frequency of the modulation signal and the frequency of the crystal oscillator is within a preset range; The oscillation amplitude detector detects the amplitude of the output signal of the crystal oscillator. If it is detected that the amplitude of the output signal of the crystal oscillator exceeds a preset amplitude value, the broadband modulator stops inputting the modulation signal to the crystal oscillator, including: If it is detected that the amplitude of the output signal of the crystal oscillator exceeds the preset amplitude value, the oscillation amplitude detector is used to send a first feedback signal to the excitation signal generator and / or the broadband modulator; the first feedback signal is used to control the excitation signal generator and / or the broadband modulator to stop signal output.

6. The crystal oscillation method according to claim 5, characterized in that: Also includes: When the crystal oscillator is enabled, The bias current controller inputs a bias current to the amplifier; The amplifier inputs the amplified bias current into the crystal oscillator; An impedance stabilization controller provides impedance to the crystal oscillator.

7. An electronic device, characterized in that: The invention comprises the crystal oscillator circuit as claimed in any one of claims 1 to 4.

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