Crystal oscillator and electronic device
By introducing a comparator module into the crystal oscillator to generate an analog difference signal and digitize it, combined with the frequency correction of the vibration module, the frequency drift problem was solved and the timing accuracy was improved.
Patent Information
- Application Number
- CN202423054321.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-10
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2034-12-10
AI Technical Summary
Crystal oscillators are susceptible to frequency drift due to external factors during use, resulting in low timing accuracy.
The comparison module generates an analog difference signal, the conversion module digitizes it, and the vibration module corrects the frequency of the high-frequency crystal oscillator signal based on the digital difference signal, thus achieving frequency correction.
This improves the timing accuracy of the crystal oscillator.
Smart Images
Figure CN223599824U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to electronic technical field especially, relate to a crystal oscillator and electronic equipment. BACKGROUND
[0002] Crystal oscillator is a kind of electronic equipment using the piezoelectric effect of quartz crystal to generate stable frequency signal.Crystal oscillator plays the key role of providing basic clock signal in electronic equipment, ensures that each part of electronic equipment keeps synchronization.
[0003] However, crystal oscillator is prone to frequency drift due to the influence of external factors such as welding when using, thereby causing the low timing accuracy of crystal oscillator. SUMMARY
[0004] The utility model provides a kind of crystal oscillator and electronic equipment, to improve the timing accuracy of crystal oscillator.
[0005] According to an aspect of the utility model, a kind of crystal oscillator is provided, the crystal oscillator includes: comparison module, frequency division module, conversion module and vibration module;
[0006] The comparison module is connected with the frequency division module, the comparison module is also connected with the conversion module, the conversion module is also connected with the vibration module, and the vibration module is also connected with the frequency division module;
[0007] The vibration module is used to generate high-frequency crystal oscillator signal;The frequency division module is used to divide the high-frequency crystal oscillator signal into low-frequency crystal oscillator signal;The comparison module is used to access standard signal, and generates analog difference signal when the low-frequency crystal oscillator signal and the standard signal exist difference;The conversion module is used to convert the analog difference signal into digital difference signal;The vibration module is also used to correct the frequency of the high-frequency crystal oscillator signal according to the digital difference signal.
[0008] Optionally, the comparison module includes: comparison unit and amplification unit;
[0009] The comparison unit is connected with the frequency division module, and the comparison unit is also connected with the amplification unit, and the amplification unit is also connected with the conversion module;
[0010] The comparison unit is used to access standard signal, and generates initial analog difference signal when the low-frequency crystal oscillator signal and the standard signal exist difference;The amplification unit is used to amplify the initial analog difference signal to generate the analog difference signal.
[0011] Optionally, the comparison unit includes: frequency discriminator;
[0012] The first input end of the phase-frequency detector is connected to the standard signal; the second input end of the phase-frequency detector is connected to the frequency division module; the first signal output end and the second signal output end of the phase-frequency detector are connected to the amplification unit.
[0013] Optionally, the amplification unit comprises a charge pump; the charge pump is connected between the comparison unit and the conversion module.
[0014] Optionally, the conversion module comprises a conversion unit and a filter unit.
[0015] The conversion unit is connected to the comparison module, the conversion unit is further connected to the filter unit, and the filter unit is further connected to the vibration module.
[0016] The conversion unit is configured to convert the analog difference signal into an initial digital difference signal; and the filter unit is configured to filter the initial digital difference signal to generate the digital difference signal.
[0017] Optionally, the conversion unit comprises an analog-to-digital converter.
[0018] Optionally, the vibration module comprises a control unit and a vibration unit.
[0019] The control unit is connected to the conversion module, the control unit is further connected to the vibration unit, and the vibration unit is further connected to the frequency division module.
[0020] The control unit is configured to control the frequency of the high-frequency crystal oscillator signal generated by the vibration unit according to the digital difference signal; and the vibration unit is configured to generate the high-frequency crystal oscillator signal.
[0021] Optionally, the vibration unit comprises a feedback resistor, an inverter, a crystal, a first variable capacitor and a second variable capacitor.
[0022] The feedback resistor, the inverter and the crystal are connected in parallel; a first end of the first variable capacitor is connected to a first end of the crystal, a second end of the first variable capacitor is grounded, a first end of the second variable capacitor is connected to a second end of the crystal, and a second end of the second variable capacitor is grounded.
[0023] Optionally, the frequency division module comprises a plurality of divide-by-two circuits.
[0024] The plurality of divide-by-two circuits are connected in series, a first divide-by-two circuit is further connected to the vibration module, and a last divide-by-two circuit is further connected to the comparison module.
[0025] According to another aspect of the present application, an electronic device is provided, which comprises the crystal oscillator of any one of the above embodiments.
[0026] The frequency division module converts the high-frequency crystal oscillator signal generated by the vibration module into a low-frequency crystal oscillator signal, the comparison module generates an analog difference signal according to the difference between the low-frequency crystal oscillator signal and a standard signal, the conversion module converts the analog difference signal into a digital difference signal, and the vibration module corrects the frequency of the high-frequency crystal oscillator signal according to the digital difference signal. The crystal oscillator of the present application can correct the frequency of the crystal oscillator signal output by the crystal oscillator, and is beneficial to improving the timing accuracy of the crystal oscillator.
[0027] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS
[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.
[0029] Figure 1 is a schematic diagram of a crystal oscillator provided by the present application;
[0030] Figure 2 is a schematic diagram of another crystal oscillator provided by the present application;
[0031] Figure 3 is a schematic diagram of another crystal oscillator provided by the present application;
[0032] Figure 4 is a schematic diagram of another crystal oscillator provided by the present application;
[0033] Figure 5 is a schematic diagram of a vibration unit provided by the present application;
[0034] Figure 6 is a schematic diagram of another crystal oscillator provided by the present application;
[0035] Figure 7 is a schematic diagram of an electronic device provided by the present application. DETAILED DESCRIPTION
[0036] In order to make the person skilled in the art better understand the technical scheme of the present application, the technical scheme in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the scope of protection of the present application.
[0037] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.
[0038] The embodiment of the present application provides a crystal oscillator. The crystal oscillator can correct the frequency of the output crystal oscillator signal, which is beneficial to improve the timing accuracy of the crystal oscillator. Figure 1 is a schematic diagram of a crystal oscillator provided by the embodiment of the present application. Referring to Figure 1 The crystal oscillator comprises a comparison module 110, a frequency division module 140, a conversion module 120 and a vibration module 130.
[0039] The comparison module 110 is connected with the frequency division module 140, the comparison module 110 is also connected with the conversion module 120, the conversion module 120 is also connected with the vibration module 130, and the vibration module 130 is also connected with the frequency division module 140; the vibration module 130 is used for generating a high-frequency crystal oscillator signal; the frequency division module 140 is used for dividing the high-frequency crystal oscillator signal into a low-frequency crystal oscillator signal; the comparison module 110 is used for accessing a standard signal Vref, and generating an analog difference signal when there is a difference between the low-frequency crystal oscillator signal and the standard signal; the conversion module 120 is used for converting the analog difference signal into a digital difference signal; and the vibration module 130 is also used for correcting the frequency of the high-frequency crystal oscillator signal according to the digital difference signal.
[0040] Specifically, the frequency division module 140 acquires the high-frequency crystal oscillator signal generated by the vibration module 130, and reduces the frequency of the high-frequency crystal oscillator signal, that is, divides the high-frequency crystal oscillator signal to generate a low-frequency crystal oscillator signal. The frequency level of the low-frequency crystal oscillator signal is consistent with the frequency level of the standard signal Vref. The standard signal Vref can be acquired through a network, for example. The frequency level of the low-frequency crystal oscillator signal and the frequency level of the standard signal Vref are both second-level. The comparison module 110 acquires the low-frequency crystal oscillator signal generated by the frequency division module 140. The comparison module 110 compares the frequency of the low-frequency crystal oscillator signal with the frequency of the standard signal Vref, and compares the phase of the low-frequency crystal oscillator signal with the phase of the standard signal, and generates an analog difference signal according to the difference between the frequency of the low-frequency crystal oscillator signal and the frequency of the standard signal and / or the difference between the phase of the low-frequency crystal oscillator signal and the phase of the standard signal. The analog difference signal is an analog signal. It should be noted that when the frequency of the low-frequency crystal oscillator signal is the same as the frequency of the standard signal and the phase of the low-frequency crystal oscillator signal is the same as the phase of the standard signal, the comparison module 110 has no output, that is, the comparison module 110 does not generate an analog difference signal at this time. The conversion module 120 acquires the analog difference signal and digitizes the analog difference signal to generate a digital difference signal. The vibration module 130 acquires the digital difference signal and corrects the frequency of the generated high-frequency crystal oscillator signal according to the digital difference signal.
[0041] The frequency division module 140 of the embodiment of the utility model converts the high-frequency crystal oscillator signal generated by the vibration module 130 into a low-frequency crystal oscillator signal, the comparison module 110 generates an analog difference signal according to the difference between the low-frequency crystal oscillator signal and the standard signal Vre, the conversion module 120 converts the analog difference signal into a digital difference signal, and the vibration module 130 corrects the frequency of the high-frequency crystal oscillator signal according to the digital difference signal. The crystal oscillator of the embodiment of the utility model can correct the frequency of the crystal oscillator signal outputted, which is beneficial to improve the timing accuracy of the crystal oscillator.
[0042] Figure 2 It is another schematic view of the crystal oscillator provided by the embodiment of the utility model. On the basis of the above embodiment, the comparison module 110 comprises a comparison unit 111 and an amplification unit 112. Figure 2 The comparison unit 111 is connected with the frequency division module 140, the comparison unit 111 is also connected with the amplification unit 112, and the amplification unit 112 is also connected with the conversion module 120; the comparison unit 111 is used for accessing the standard signal, and generates an initial analog difference signal when there is a difference between the low-frequency crystal oscillator signal and the standard signal; the amplification unit 112 is used for amplifying the initial analog difference signal to generate an analog difference signal.
[0043] The comparison unit 111 is connected with the frequency division module 140, the comparison unit 111 is also connected with the amplification unit 112, and the amplification unit 112 is also connected with the conversion module 120; the comparison unit 111 is used for accessing the standard signal, and generates an initial analog difference signal when there is a difference between the low-frequency crystal oscillator signal and the standard signal; the amplification unit 112 is used for amplifying the initial analog difference signal to generate an analog difference signal.
[0044] Specifically, the comparison unit 111 acquires the low-frequency crystal oscillator signal generated by the frequency division module 140. The comparison unit 111 compares the frequency of the low-frequency crystal oscillator signal with the frequency of the standard signal Vref, and compares the phase of the low-frequency crystal oscillator signal with the phase of the standard signal, and generates an initial analog difference signal according to the difference between the frequency of the low-frequency crystal oscillator signal and the frequency of the standard signal and / or the difference between the phase of the low-frequency crystal oscillator signal and the phase of the standard signal. The amplification unit 112 acquires the initial analog difference signal generated by the comparison unit 111, and amplifies the initial analog difference signal to increase the amplitude of the initial analog difference signal to meet the requirements of the conversion module 120 on the input signal. The amplification unit 112 may, for example, include a charge pump. The charge pump is a circuit device that uses the charging and discharging of a capacitor to realize voltage conversion, which can increase or decrease the input voltage to meet specific power supply requirements.
[0045] Exemplarily, the analog difference signal can be a level signal, and the analog difference signal includes a low level signal and a high level signal. The comparison unit 111 can include a frequency discriminator. The first input end of the frequency discriminator is connected to the standard signal; the second input end of the frequency discriminator is connected to the frequency division module; and the first signal output end and the second signal output end of the frequency discriminator are both connected to the amplification unit. When the frequency of the low-frequency crystal oscillator signal is lower than the frequency of the standard signal and / or the phase of the low-frequency crystal oscillator signal is lower than the phase of the standard signal, the frequency discriminator generates a high level signal and outputs the high level signal through the first output end of the frequency discriminator; when the frequency of the low-frequency crystal oscillator signal is higher than the frequency of the standard signal and / or the phase of the low-frequency crystal oscillator signal is higher than the phase of the standard signal, the frequency discriminator generates a low level signal and outputs the low level signal through the second output end of the frequency discriminator.
[0046] Figure 3 is a schematic view of another crystal oscillator provided by the embodiment of the present application. On the basis of the above-mentioned embodiments, optionally, with reference to Figure 3 The conversion module 120 includes a conversion unit 121 and a filter unit 122.
[0047] The conversion unit 121 is connected to the comparison module 110, and the conversion unit 121 is also connected to the filter unit 122, and the filter unit 121 is also connected to the vibration module 130; the conversion unit 121 is used to convert the analog difference signal into an initial digital difference signal; and the filter unit 122 is used to filter the initial digital difference signal to generate a digital difference signal.
[0048] Specifically, the converting unit 121 acquires the analog difference signal and digitizes the analog difference signal to generate an initial digital difference signal. The filtering unit 122 acquires the initial digital difference signal and filters out noise in the initial digital difference signal, that is, generates a digital difference signal, to improve the signal quality. Illustratively, the converting unit 121 can include an analog-to-digital converter; and the filtering unit can include a digital filter. The analog-to-digital converter (ADC) is an electronic element that converts an analog signal into a digital signal; and the digital filter is a device composed of a digital multiplier, an adder and a delay unit, which can change the relative proportion of frequency components contained in the input signal or filter out certain frequency components. Optionally, the digital filter can be a truncation filter.
[0049] Figure 4 is a schematic diagram of another crystal oscillator provided by the embodiment of the present application. On the basis of the above-mentioned embodiments, optionally, referring to Figure 4 , the vibration module 130 includes a control unit 131 and a vibration unit 132.
[0050] The control unit 131 is connected with the converting module 120, and the control unit 131 is also connected with the vibration unit 132, and the vibration unit 132 is also connected with the frequency dividing module 140; the control unit 131 is used for controlling the frequency of the high-frequency crystal oscillator signal generated by the vibration unit 132 according to the digital difference signal; and the vibration unit 132 is used for generating the high-frequency crystal oscillator signal.
[0051] Figure 5 is a schematic diagram of a vibration unit provided by the embodiment of the present application. On the basis of the above-mentioned embodiments, optionally, referring to Figure 5 , the vibration unit 132 includes a feedback resistor R1, an inverter NOT, a crystal Y, a first variable capacitor C1 and a second variable capacitor C2.
[0052] The feedback resistor R1, the inverter NOT and the crystal Y are connected in parallel; a first end of the first variable capacitor C1 is connected with a first end of the crystal Y, a second end of the first variable capacitor C1 is grounded, a first end of the second variable capacitor C2 is connected with a second end of the crystal Y, and a second end of the second variable capacitor C2 is grounded.
[0053] Specifically, the control unit 131 acquires the digital difference signal, and controls the capacitance values of the variable capacitor C1 and the variable capacitor C2 according to the digital difference signal, so as to realize the control of the frequency of the high-frequency crystal oscillator signal. Wherein, the first variable capacitor C1 and the second variable capacitor C2 both include a moving piece and a fixed piece, the moving piece and the fixed piece are parallel to each other, and the center of the moving piece and the center of the fixed piece are located on the same straight line. The control unit 131 controls the operation of the moving piece to make the moving piece close to or away from the fixed piece to realize the control of the first variable capacitor C1 and the second variable capacitor C2. Wherein, when the moving piece is close to the fixed piece, the capacitance value of the capacitor increases; when the moving piece is away from the fixed piece, the capacitance value of the capacitor decreases.
[0054] Figure 6 is a schematic diagram of another crystal oscillator provided by the embodiment of the present application. On the basis of the above-mentioned embodiments, optionally, referring to Figure 6 , the frequency division module 140 comprises a plurality of divide-by-two circuits 141.
[0055] The plurality of divide-by-two circuits 141 are connected in series, the first divide-by-two circuit 141 is further connected with the vibration module 130, and the last divide-by-two circuit 141 is further connected with the comparison module 110.
[0056] Wherein, the divide-by-two circuit 141 can reduce the frequency of the input clock signal by half, and output a period signal when triggering twice in each input clock cycle.
[0057] The embodiment of the present application further provides an electronic device. Figure 7 is a schematic diagram of an electronic device provided by the embodiment of the present application. Referring to Figure 7 , the electronic device 10 comprises the crystal oscillator 100 provided by any of the above-mentioned embodiments.
[0058] Wherein, the electronic device 10 provided by the embodiment has the beneficial effects of the crystal oscillator 100 provided by any of the above-mentioned embodiments, which will not be repeated here.
[0059] It should be understood that the various forms of flow shown above can be reordered, added or deleted. For example, the steps described in the present application can be executed in parallel, sequentially or in different order, as long as the desired results of the technical solutions of the present application can be achieved, which will not be limited herein.
[0060] The above specific embodiments do not constitute a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principles of the present application shall be included in the protection scope of the present application.
Claims
1. A crystal oscillator characterized by, The application relates to a frequency correction device for a high-frequency crystal oscillator. The device comprises a comparison module, a frequency division module, a conversion module and a vibration module. The comparison module is connected with the frequency division module, and is also connected with the conversion module. The vibration module is used for generating a high-frequency crystal oscillator signal.
2. The crystal oscillator of claim 1, wherein, The frequency division module is used for dividing the high-frequency crystal oscillator signal into a low-frequency crystal oscillator signal. The comparison module is used for inputting a standard signal and generating an analog difference signal when the low-frequency crystal oscillator signal is different from the standard signal. The conversion module is used for converting the analog difference signal into a digital difference signal.
3. The crystal oscillator of claim 2, wherein, The vibration module is also used for correcting the frequency of the high-frequency crystal oscillator signal according to the digital difference signal. The comparison module comprises a comparison unit and an amplification unit.
4. The crystal oscillator of claim 2, wherein, The comparison unit is connected with the frequency division module and is also connected with the amplification unit.
5. The crystal oscillator of claim 1, wherein The comparison unit is used for inputting a standard signal and generating an initial analog difference signal when the low-frequency crystal oscillator signal is different from the standard signal. The amplification unit is used for amplifying the initial analog difference signal to generate the analog difference signal. The comparison unit comprises a frequency discriminator.
6. The crystal oscillator of claim 5, wherein, The first input end of the frequency discriminator is connected with the standard signal.
7. The crystal oscillator of claim 1, wherein The second input end of the frequency discriminator is connected with the frequency division module. The first signal output end and the second signal output end of the frequency discriminator are both connected with the amplification unit. The amplification unit comprises a charge pump.
8. The crystal oscillator of claim 7, wherein, The charge pump is connected between the comparison unit and the conversion module. The conversion module comprises a conversion unit and a filter unit.
9. The crystal oscillator of claim 1, wherein, The conversion unit is connected with the comparison module and is also connected with the filter unit. The conversion unit is used for converting the analog difference signal into an initial digital difference signal. The filter unit is used for filtering the initial digital difference signal to generate the digital difference signal. The conversion unit comprises an analog-to-digital converter. The vibration module comprises a control unit and a vibration unit. The control unit is connected with the conversion module and is also connected with the vibration unit. The control unit is used for controlling the frequency of the high-frequency crystal oscillator signal generated by the vibration unit according to the digital difference signal. The vibration unit is used for generating the high-frequency crystal oscillator signal. The vibration unit comprises a feedback resistor, an inverter, a crystal, a first variable capacitor and a second variable capacitor. The feedback resistor, the inverter and the crystal are connected in parallel. The first end of the first variable capacitor is connected with the first end of the crystal, the second end of the first variable capacitor is grounded, the first end of the second variable capacitor is connected with the second end of the crystal, and the second end of the second variable capacitor is grounded. The frequency division module comprises a plurality of two-division circuits. A plurality of said frequency division circuits are connected in series, a first said frequency division circuit is further connected to said vibration module, and a last said frequency division circuit is further connected to said comparison module.
10. An electronic device, comprising: A crystal oscillator comprising a crystal oscillator as claimed in any of claims 1-9.