A phase-locked loop circuit and control method

Abstract

The embodiment of the application provides a phase-locked loop circuit and a control method, and relates to the technical field of integrated circuit manufacturing, and the phase-locked loop circuit comprises: a frequency discriminator phase detector, which is used for receiving a reference frequency signal and a feedback frequency signal, outputting a function of a signal phase difference by comparing the phase of the reference frequency signal and the feedback frequency signal, and the function of the signal phase difference comprising: a first voltage and a second voltage; a voltage controller, which is used for converting the function of the signal phase difference into a linearly changing control voltage and outputting the control voltage to a voltage-controlled oscillator; the voltage-controlled oscillator, which is used for receiving the control voltage and generating an output signal corresponding to the control voltage; and a frequency divider, which is used for frequency dividing the output signal of the voltage-controlled oscillator to obtain the feedback frequency signal and output the feedback frequency signal to the frequency discriminator phase detector. In this way, the area of the entire phase-locked loop is saved, nonlinear problems such as leakage current and charge-discharge current mismatch are avoided, and the jitter and noise of the entire phase-locked loop are effectively reduced.

Description

Technical Field

[0001] This application relates to the field of integrated circuit manufacturing technology, and in particular to a phase-locked loop circuit and control method. Background Technology

[0002] A phase-locked loop (PLL) is a feedback control circuit that uses an externally input reference frequency signal to control the frequency and phase of an internal oscillation signal. During operation, when the frequency of the output signal equals the frequency of the input signal, the output voltage maintains a fixed phase difference with the input voltage; that is, the phase of the output voltage is locked to the input voltage, hence the name "phase-locked loop."

[0003] Phase-locked loops in related technologies, such as Figure 1 As shown, a phase-locked loop (PLL) consists of a phase detector (PD) / phase-frequency detector (PFD), a low-pass filter (LPF), a voltage-controlled oscillator (VCO), and a divider. Since a PLL typically comprises a charge pump and a low-pass filter, the presence of these components leads to nonlinear issues such as leakage current, charge pump switching delay mismatch, and charge / discharge current mismatch. These problems can cause fluctuations in the charge pump output voltage, which in turn cause fluctuations in the VCO output frequency, thus reducing the noise performance of the output clock. Summary of the Invention

[0004] This application provides a phase-locked loop circuit and control method to at least solve the above-mentioned technical problems existing in the prior art.

[0005] The technical solution of this application embodiment is implemented as follows:

[0006] In a first aspect, embodiments of this application provide a phase-locked loop circuit, the phase-locked loop circuit including: a frequency and phase detector, a voltage controller, a voltage-controlled oscillator, and a frequency divider;

[0007] The frequency and phase detector is used to receive a reference frequency signal and a feedback frequency signal, and outputs a function of the signal phase difference by comparing the phases of the reference frequency signal and the feedback frequency signal. The function of the signal phase difference includes: a first voltage and a second voltage.

[0008] The voltage controller is used to convert the signal phase difference into a linearly changing control voltage, and output the control voltage to the voltage-controlled oscillator.

[0009] The voltage-controlled oscillator is configured to receive the control voltage and generate an output signal corresponding to the control voltage.

[0010] The frequency divider is configured to divide the output signal of the voltage-controlled oscillator to obtain a feedback frequency signal and output the feedback frequency signal to the phase-frequency detector.

[0011] In the above scheme, the voltage controller comprises a source electrode, a drain electrode, a gate electrode, a first electrode, a second electrode, a first switch, a second switch, a first layer of two-dimensional semiconductor material, a second layer of two-dimensional semiconductor material, and a third layer of two-dimensional semiconductor material.

[0012] The second layer of two-dimensional semiconductor material and the second electrode are located on the third layer of two-dimensional semiconductor material, and the second electrode is located in a first direction of the second layer of two-dimensional semiconductor material.

[0013] The source electrode, the drain electrode, and the first layer of two-dimensional semiconductor material are located on the second layer of two-dimensional semiconductor material, and the source electrode is located in a first direction of the first layer of two-dimensional semiconductor material, and the drain electrode is located in a second direction of the first layer of two-dimensional semiconductor material.

[0014] The first electrode and the gate electrode are located on the first layer of two-dimensional semiconductor material, and the first electrode is located in a first direction of the gate electrode, and the gate electrode is located between the first electrode and the drain electrode.

[0015] One end of the first switch is connected to the first electrode, one end of the second switch is connected to the second electrode, and the other end of the first switch and the other end of the second switch are both connected to the source electrode.

[0016] In the above scheme, the voltage controller further comprises an insulating layer and a substrate.

[0017] The insulating layer is configured to isolate different electrodes and materials.

[0018] The substrate is configured to provide a stable carrier for the voltage controller.

[0019] In the above scheme, the insulating layer is configured to isolate the second electrode and the source electrode, isolate the source electrode and the first electrode, isolate the first electrode and the drain electrode, and isolate the gate electrode and the first layer of two-dimensional semiconductor material.

[0020] In the above scheme, the source electrode receives a source voltage input by an external power supply and is configured to generate a current.

[0021] The gate receives a gate voltage input by an external power supply for regulating the conductive layer; the conductive layer comprises the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material, which are materials for providing electrons and holes;

[0022] The drain is used for outputting the control voltage.

[0023] The first switch and the second switch are respectively used for controlling the on-off of the first electrode and the second electrode.

[0024] In the above scheme, the band width of the first layer of two-dimensional semiconductor material is greater than that of the second layer of two-dimensional semiconductor material, and the band width of the second layer of two-dimensional semiconductor material is greater than that of the third layer of two-dimensional semiconductor material.

[0025] In the above scheme, the conduction band of the first layer of two-dimensional semiconductor material is at the top, the conduction band of the second layer of two-dimensional semiconductor material is in the middle, and the conduction band of the third layer of two-dimensional semiconductor material is at the bottom.

[0026] The valence band of the first layer of two-dimensional semiconductor material is at the bottom, the valence band of the second layer of two-dimensional semiconductor material is in the middle, and the valence band of the third layer of two-dimensional semiconductor material is at the top.

[0027] In the above scheme, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material form a heterojunction for regulating the electron and hole transport behavior of different layers of two-dimensional semiconductor materials.

[0028] In the above scheme, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material are combined by van der Waals force.

[0029] In the above scheme, when preparing the heterojunction, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material are subjected to annealing treatment to form a van der Waals interface between the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material.

[0030] In the above scheme, the first layer of two-dimensional semiconductor material is molybdenum disulfide, the second layer of two-dimensional semiconductor material is rhenium disulfide, and the first layer of two-dimensional semiconductor material is chromium diselenide.

[0031] In the above scheme, the voltage controller is used to control the state of the first switch and the second switch according to the first voltage and the second voltage, and the state is open or closed.

[0032] In different states, the voltage controller generates different control voltages.

[0033] In the above solution, if the first switch and the second switch are both open, the source, the drain, the gate are powered on, and the source and the drain generate a control voltage with a first voltage value;

[0034] If the first switch is closed and the second switch is open, the source, the first electrode, the drain, and the gate are powered on, and the source and the drain generate a control voltage with a second voltage value; the second voltage value is greater than the first voltage value; the magnitude of the second voltage value is in proportional relationship with the duration of the first switch being continuously closed;

[0035] If the first switch is open and the second switch is closed, the source, the second electrode, the drain, and the gate are powered on, and the source and the drain generate a control voltage with a third voltage value, the third voltage value being less than the first voltage value; the magnitude of the third voltage value is in proportional relationship with the duration of the second switch being continuously closed.

[0036] In a second aspect, the embodiments of the present application provide a control method of a phase-locked loop circuit, applied to the phase-locked loop circuit described above, and the method comprises:

[0037] The frequency discriminator and phase detector receives a reference frequency signal and a feedback frequency signal, and outputs a function of a signal phase difference by comparing the phases of the reference frequency signal and the feedback frequency signal, the function of the signal phase difference comprising: a first voltage and a second voltage;

[0038] The voltage controller converts the function of the signal phase difference into a control voltage that changes linearly, and outputs the control voltage to the voltage-controlled oscillator;

[0039] The voltage-controlled oscillator receives the control voltage and generates an output signal in a corresponding relationship with the control voltage;

[0040] The frequency divider divides the output signal of the voltage-controlled oscillator to obtain a feedback frequency signal, and outputs the feedback frequency signal to the frequency discriminator and phase detector.

[0041] In the above solution, the function of the signal phase difference output by comparing the phases of the reference frequency signal and the feedback frequency signal comprises:

[0042] If the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase of the reference frequency signal is the same as the phase of the feedback frequency signal, the first voltage and the second voltage output by the frequency discriminator and phase detector are both low;

[0043] If the frequency of the reference frequency signal is greater than the frequency of the feedback frequency signal, or the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal and the phase of the reference frequency signal is ahead of the feedback frequency signal, the first voltage output by the phase-frequency detector is high and the second voltage is low, and the maintaining time of the first voltage is proportional to the phase difference between the reference frequency signal and the feedback frequency signal; correspondingly,

[0044] If the frequency of the reference frequency signal is less than the frequency of the feedback frequency signal, or the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal and the phase of the reference frequency signal is behind the feedback frequency signal, the first voltage output by the phase-frequency detector is low and the second voltage is high, and the maintaining time of the second voltage is proportional to the phase difference between the reference frequency signal and the feedback frequency signal;

[0045] Correspondingly, the voltage controller converts the function of the signal phase difference into the linearly changed control voltage, comprising:

[0046] The first switch and the second switch of the voltage controller are both disconnected, generating the control voltage with the first voltage value;

[0047] The first switch of the voltage controller is closed and the second switch is disconnected, generating the control voltage with the second voltage value; the second voltage value is greater than the first voltage value; the size of the second voltage value is in proportional relationship with the time length of the first switch being continuously closed;

[0048] The first switch of the voltage controller is disconnected and the second switch is closed, generating the control voltage with the third voltage value, the third voltage value being less than the first voltage value; the size of the third voltage value is in proportional relationship with the time length of the second switch being continuously closed.

[0049] The embodiments of the present application have the following beneficial effects:

[0050] The phase-locked loop circuit and the control method provided by the embodiment of the application, the phase-locked loop circuit comprises: a frequency discriminator, a voltage controller, a voltage-controlled oscillator and a frequency divider; the frequency discriminator is configured to receive a reference frequency signal and a feedback frequency signal, compare the phases of the reference frequency signal and the feedback frequency signal, and output a function of a signal phase difference, wherein the function of the signal phase difference comprises a first voltage and a second voltage; the voltage controller is configured to convert the function of the signal phase difference into a control voltage that changes linearly, and output the control voltage to the voltage-controlled oscillator; the voltage-controlled oscillator is configured to receive the control voltage and generate an output signal corresponding to the control voltage; and the frequency divider is configured to divide the output signal of the voltage-controlled oscillator to obtain the feedback frequency signal, and output the feedback frequency signal to the frequency discriminator. In this way, by converting the function of the signal phase difference into the control voltage that changes linearly through the voltage controller, the area of the entire phase-locked loop is saved, and the nonlinear problems such as leakage current, charge pump switch delay mismatch, charge and discharge current mismatch and the like are avoided, thereby effectively reducing the jitter and noise of the entire phase-locked loop.

[0051] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the application, nor is it used to limit the scope of the application. Other features of the application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 A structure diagram of a phase loop circuit in the related art;

[0053] Figure 2 A structure diagram of a phase-locked loop circuit provided by the embodiment of the application;

[0054] Figure 3 A circuit profile diagram of a voltage controller provided by the embodiment of the application;

[0055] Figure 4 A circuit top view of a voltage controller provided by the embodiment of the application;

[0056] Figure 5 A schematic diagram of a two-dimensional material heterojunction band structure in a voltage controller provided by the embodiment of the application;

[0057] Figure 6 A schematic diagram of a two-dimensional material heterojunction band structure example provided by the embodiment of the application;

[0058] Figure 7 A schematic diagram of a frequency discriminator circuit logic provided by the embodiment of the application;

[0059] Figure 8A schematic diagram of logic of a voltage controller circuit provided for an embodiment of the present application is shown in FIG. 1.

[0060] Figure 9 A flowchart of a control method of a phase-locked loop circuit provided for an embodiment of the present application is shown in FIG. 4. DETAILED DESCRIPTION

[0061] In order to make the objectives, features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0062] In the following description, "some embodiments" are described, which describe a subset of all possible embodiments, but it can be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0063] If similar descriptions of "first / second" appear in the application file, the following description is added. In the following description, the terms "first\second\third" are only to distinguish similar objects, and do not represent a specific order of the objects. It can be understood that "first\second\third" can be interchanged in a specific order or sequence as allowed, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0064] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0065] Figure 2 A structural schematic diagram of a phase-locked loop circuit provided for an embodiment of the present application is shown in FIG. 2, which includes a frequency discriminator, a voltage controller, a voltage-controlled oscillator, and a frequency divider. Figure 2

[0066] The frequency discriminator is configured to receive a reference frequency signal and a feedback frequency signal, and output a function of a signal phase difference by comparing the phase of the reference frequency signal and the feedback frequency signal, wherein the function of the signal phase difference includes a first voltage and a second voltage.

[0067] The voltage controller is configured to convert the function of the signal phase difference into a control voltage, and output the control voltage to the voltage-controlled oscillator. ​

[0068] The voltage-controlled oscillator is configured to receive the control voltage and generate an output signal having a corresponding relationship with the control voltage.

[0069] The frequency divider is configured to divide the output signal of the voltage-controlled oscillator to obtain a feedback frequency signal and output the feedback frequency signal to the phase frequency detector.

[0070] In some embodiments, the phase frequency detector (PFD) receives a reference frequency signal (one from an external signal) and a feedback frequency signal (one from the output signal of the voltage-controlled oscillator, after being divided by the frequency divider). The working principle is to compare the phase difference of the two frequency signals and output a function signal related to the phase difference, here a voltage signal (including a first voltage and a second voltage), reflecting the phase difference of the two voltages.

[0071] The voltage controller converts the phase difference function (including the first voltage and the second voltage) output by the phase frequency detector into a linearly changing control voltage. The working principle is to convert the phase difference signal into a controllable control voltage, the size of the control voltage determines the frequency of the output signal of the voltage-controlled oscillator, and the control voltage changes based on the change of the phase difference of the two voltages.

[0072] The voltage-controlled oscillator (VCO) receives the control voltage from the voltage controller and generates an output signal having a certain corresponding relationship with the control voltage. Through the control voltage, the frequency and phase of the output signal of the VCO are gradually made to maintain a fixed synchronous relationship with the reference frequency signal.

[0073] The frequency divider divides the output signal of the voltage-controlled oscillator to obtain a feedback frequency signal, which is usually reduced to a range that can be processed by the phase frequency detector, that is, the high-frequency output signal of the voltage-controlled oscillator is divided to generate a lower frequency signal. The lower frequency signal will be fed back to the phase frequency detector to form a closed-loop control. Here, the purpose of generating a lower frequency signal is to obtain a frequency signal matched with the original reference frequency signal, and to maintain the stability of the system through feedback control.

[0074] The phase-locked loop circuit provided by the embodiments of the present application inputs the first voltage and the second voltage output by the phase frequency detector to the voltage controller to replace the charge pump and the low-pass filter circuit, and converts the frequency or phase difference information reflected by the first voltage and the second voltage into a linearly changing control voltage VctrlCompared with using a charge pump and a low-pass filter, the phase-locked loop circuit of the embodiment of the application does not have nonlinear problems such as leakage current, charge pump switch delay mismatch, charge and discharge current mismatch, and effectively reduces the jitter and noise of the entire phase-locked loop.

[0075] In some embodiments, the voltage controller comprises: a source, a drain, a gate, a first electrode, a second electrode, a first switch, a second switch, a first layer of two-dimensional semiconductor material, a second layer of two-dimensional semiconductor material, a third layer of two-dimensional semiconductor material;

[0076] The second layer of two-dimensional semiconductor material and the second electrode are located on the third layer of two-dimensional semiconductor material, and the second electrode is located in a first direction of the second layer of two-dimensional semiconductor material;

[0077] The source, the drain and the first layer of two-dimensional semiconductor material are located on the second layer of two-dimensional semiconductor material, and the source is located in a first direction of the first layer of two-dimensional semiconductor material, and the drain is located in a second direction of the first layer of two-dimensional semiconductor material;

[0078] The first electrode and the gate are located on the first layer of two-dimensional semiconductor material, and the first electrode is located in a first direction of the gate, and the gate is located between the first electrode and the drain;

[0079] One end of the first switch is connected to the first electrode, one end of the second switch is connected to the second electrode, and the other end of the first switch and the other end of the second switch are both connected to the source.

[0080] Here, a structure and a switch utilizing a multi-layer two-dimensional semiconductor material are provided to realize precise current and voltage control. Through the control of the gate voltage and the switch, the conductivity of the circuit can be flexibly adjusted, providing efficient and precise electronic regulation function.

[0081] In some embodiments, the voltage controller further comprises: an insulating layer, a substrate;

[0082] The insulating layer is used to isolate different electrodes and materials;

[0083] The substrate is used to provide a stable carrier for the voltage controller.

[0084] Specifically, the insulating layer is used to isolate the second electrode and the source, isolate the source and the first electrode, isolate the first electrode and the drain, and isolate the gate and the first layer of two-dimensional semiconductor material.

[0085] Here, the insulating layer can be made of silicon dioxide, silicon nitride or other materials with good insulating properties, which can prevent electrical interference between different materials or electrodes, ensuring the stability and reliability of the device.

[0086] The substrate can be made of a silicon wafer or other similar materials, which have good mechanical strength and stability, and are used to ensure the stability of the structure and avoid deformation or damage caused by external pressure, temperature changes or external forces.

[0087] Here, an example of a voltage controller is provided, as shown in Figure 3 A circuit profile view of a voltage controller is provided, as shown in Figure 4 A circuit top view of a voltage controller is provided. In the figure, the first layer of material represents the first layer of two-dimensional semiconductor material, the second layer of material represents the second layer of two-dimensional semiconductor material, and the third layer of material represents the third layer of two-dimensional semiconductor material.

[0088] As can be seen, the third layer of two-dimensional semiconductor material is located on the substrate; the second layer of two-dimensional semiconductor material and electrode 2 (equivalent to the second electrode) are located on the third layer of two-dimensional semiconductor material, and electrode 2 is located in the first direction (as shown in the figure, pointing to the left) of the second layer of two-dimensional semiconductor material; the first layer of two-dimensional semiconductor material, source and drain are located on the second layer of two-dimensional semiconductor material, and the source is located in the first direction (as shown in the figure, pointing to the left) of the first layer of two-dimensional semiconductor material, and the drain is located in the second direction (as shown in the figure, pointing to the right) of the first layer of two-dimensional semiconductor material; electrode 1 is located on the first layer of two-dimensional semiconductor material, and there is an insulating layer on the first layer of two-dimensional semiconductor material, and the gate is located on the insulating layer, and electrode 1 is located in the first direction (as shown in the figure, pointing to the left) of the gate, and the gate is located between the first electrode and the drain.

[0089] The insulating layer can be a whole, which is used to isolate electrode 2 and source, isolate source and electrode 1, isolate electrode 1 and the drain, and isolate the gate and the first layer of two-dimensional semiconductor material. The positions of the source and electrode 1 can be partially removed or cut to form a gap or gap, which is used to allow the source and electrode 1 to embed or contact the corresponding circuit part, but the insulating layer remains isolated elsewhere to prevent unnecessary electrical interference or short circuit.

[0090] In this way, a whole insulating layer is provided for electrodes, sources, drains and other elements to provide necessary electrical isolation, ensuring that they do not interfere with each other or short circuit.

[0091] In addition, the area of the first layer of two-dimensional semiconductor material can be less than or equal to the area of the second layer of two-dimensional semiconductor material, and the area of the second layer of two-dimensional semiconductor material can be less than or equal to the area of the third layer of two-dimensional semiconductor material.

[0092] In some embodiments, the source receives a source voltage input from an external power source for generating a current;

[0093] The gate receives a gate voltage input from an external power source for regulating the conductive layer; the conductive layer includes: the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material, for providing materials for generating electrons and holes;

[0094] The drain is used to output the control voltage;

[0095] The first switch and the second switch are respectively used to control the on-off of the first electrode and the second electrode.

[0096] Here, the external power source can be a constant power source that meets the requirements of transistor design, without limitation on voltage value. The source is the inflow port of the voltage, and the drain is the outflow port of the voltage.

[0097] The first switch and the second switch are switch elements used to control the current flow between the two electrodes, and the on-off state of the switch is used to adjust the conduction state of the circuit.

[0098] Here, the gate is a control electrode between the source and the drain, and does not directly contact the conductive layer, but through the action of the electric field, the gate can affect the distribution of the current carriers (electrons or holes) in the conductive layer. When the gate voltage is applied, an electric field is formed below the conductive layer (formed by semiconductor material), which affects the concentration of electrons or holes in the conductive layer. That is, the gate controls whether a conductive channel is formed and the conductive performance of the channel.

[0099] Specifically, when the gate voltage is high, the electric field formed affects the conductive layer, allowing current to flow from the source to the drain, and the device is in the on state; when the gate voltage is low, the electric field is not enough to form an effective conductive channel on the conductive layer, and the current cannot flow from the source to the drain, and the device is in the off state.

[0100] Here, two-dimensional semiconductor materials are an important part of nanomaterials, and two-dimensional semiconductor materials are a general term for a class of materials, referring to thin film materials with only one or a few atomic layers thick. Different two-dimensional semiconductor materials can form two-dimensional heterojunction semiconductors to form various semiconductors with different properties and functions.

[0101] The first layer, the second layer, and the third layer of two-dimensional semiconductor material are used to provide electrons and holes. In a semiconductor, electrons are negative charge carriers, and holes are positive charge carriers. The role of the three layers of material is to generate electrons and holes, providing a source of free carriers in the material.

[0102] Here, the first switch and the second switch can be configured with a controller for controlling the states of the first switch and the second switch according to the first voltage and the second voltage. Alternatively, the first switch and the second switch can be voltage detection switches that have a control function by themselves and perform state control after receiving the first voltage and the second voltage. This is not limited here.

[0103] In combination with the above Figure 3 and Figure 4 An example is provided, in which switch 1 (equivalent to an example of the first switch) is used to connect the source and electrode 1, switch 2 (equivalent to an example of the second switch) is used to connect the source and electrode 2, the source receives a source voltage (Vsource) input by an external power source for generating current; the gate receives a gate voltage (Vgate) input by an external power source for regulating the conductive layer; and the drain is used to output a control voltage (Vctrl).

[0104] In some embodiments, the first layer of two-dimensional semiconductor material has a larger band width than the second layer of two-dimensional semiconductor material, and the second layer of two-dimensional semiconductor material has a larger band width than the third layer of two-dimensional semiconductor material.

[0105] Here, the band width refers to the energy band width of the semiconductor material, that is, the energy difference between the conduction band and the valence band in the electronic energy band structure. It is usually used to describe the electrical conductivity of the material.

[0106] The first layer of two-dimensional semiconductor material has a larger band width than the second layer of two-dimensional semiconductor material, which means that the energy difference between the electronic energy bands in the first layer of two-dimensional semiconductor material is larger, so that it has different electrical properties, such as higher conductivity or different band gap.

[0107] The second layer of two-dimensional semiconductor material has a larger band width than the third layer of two-dimensional semiconductor material, which means that the energy difference between the electronic energy bands in the second layer of two-dimensional semiconductor material is larger than that in the third layer of two-dimensional semiconductor material, so that it has different electrical properties, such as higher conductivity or different band gap.

[0108] Through the band widths of the different layers of two-dimensional semiconductor materials above, the performance of the device can be optimized, such as improving the switching speed and reducing the power consumption.

[0109] In some embodiments, the conduction band of the first layer of two-dimensional semiconductor material is at the top, the conduction band of the second layer of two-dimensional semiconductor material is in the middle, and the conduction band of the third layer of two-dimensional semiconductor material is at the bottom.

[0110] The valence band of the first layer of two-dimensional semiconductor material is at the bottom, the valence band of the second layer of two-dimensional semiconductor material is in the middle, and the valence band of the third layer of two-dimensional semiconductor material is at the top.

[0111] Here, the conduction band of the first layer of two-dimensional semiconductor material is at the topmost, indicating that the conduction band energy of the first layer of two-dimensional semiconductor material is the highest, and the electron is easier to jump from the valence band into the conduction band.

[0112] Correspondingly, the conduction band of the second layer of two-dimensional semiconductor material is in the middle, indicating that the conduction band energy of the second layer of two-dimensional semiconductor material is between the first layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material, i.e., the conduction band energy of the second layer of two-dimensional semiconductor material is relatively in the middle.

[0113] The conduction band of the third layer of two-dimensional semiconductor material is at the bottommost, indicating that the conduction band energy of the third layer of two-dimensional semiconductor material is the lowest among the three layers of materials, meaning that the electron on the conduction band of this layer needs a higher energy to be excited into the conduction band, so its conductivity is relatively weak.

[0114] Here, the valence band of the third layer of two-dimensional semiconductor material is at the topmost, indicating that the valence band energy of the third layer of two-dimensional semiconductor material is the highest, and the electron is in a relatively high energy state.

[0115] The valence band of the second layer of two-dimensional semiconductor material is in the middle, indicating that the valence band energy of the second layer of two-dimensional semiconductor material is between the first layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material, and its valence band energy is between the two.

[0116] The valence band of the third layer of two-dimensional semiconductor material is at the topmost, indicating that the valence band energy of the third layer of two-dimensional semiconductor material is the highest among the three layers of materials, and the electron of this layer is in a high energy state and is difficult to jump to the conduction band.

[0117] Through the above design of band width and energy band arrangement, for the first layer of two-dimensional semiconductor material, after being excited, the electron on the conduction band can be transferred to the conduction band of the second layer of two-dimensional semiconductor material or the conduction band of the third layer of two-dimensional semiconductor material, and the hole on the valence band can be transferred to the valence band of the second layer of two-dimensional semiconductor material or the valence band of the third layer of two-dimensional semiconductor material.

[0118] For the second layer of two-dimensional semiconductor material, after being excited, the electron on the conduction band can be transferred to the conduction band of the third layer of two-dimensional semiconductor material, and the hole on the valence band can be transferred to the valence band of the third layer of two-dimensional semiconductor material.

[0119] In some embodiments, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material form a heterojunction for regulating the electron and hole transport behavior of different layers of two-dimensional semiconductor materials.

[0120] Here, the heterojunction refers to an interface composed of two or more different types of materials.

[0121] Electrons and holes are the main carriers in semiconductor materials. Electrons are negatively charged particles, and holes are positively charged electron vacancies. In heterojunctions, different layers of semiconductor materials regulate the transport behavior of electrons and holes through different energy band structures (the positions of conduction bands and valence bands, etc.). This regulation can be achieved by:

[0122] Changing the migration speed of carriers: the energy bands between different materials affect the migration speed of electrons and holes;

[0123] Influencing the distribution of carriers: heterojunctions can cause electrons and holes to be unevenly distributed between different material layers, affecting the conductivity and electronic properties of the material;

[0124] Adjusting the carrier concentration: through different energy band adjustments, heterojunctions can affect the concentration distribution of electrons and holes.

[0125] Here, by utilizing heterojunctions (composed of different layers of two-dimensional semiconductor materials), the transport behavior of electrons and holes between different layers can be precisely regulated, thereby optimizing the performance of the material in different electronic and optoelectronic applications.

[0126] In some embodiments, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material are combined through van der Waals forces.

[0127] Here, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material are combined with each other through van der Waals forces, so that the crystal structure and lattice constant of each two-dimensional semiconductor material do not need to be matched to obtain a good performance heterojunction.

[0128] The use of van der Waals forces helps to adjust the electronic properties of these materials, especially in heterojunctions and multi-layer structures, enabling more precise regulation. And this binding force is weak, making the different layers have a certain independence and adjustability.

[0129] In some embodiments, during the preparation of the heterojunction, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material are subjected to annealing treatment to form a van der Waals interface between the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material.

[0130] Here, annealing treatment is performed during the preparation of the heterojunction to ensure the formation of a good van der Waals interface between the three two-dimensional semiconductor materials, which is beneficial to improving the transfer performance of electrons and holes and optimizing the performance of the voltage controller. Moreover, two-dimensional semiconductor materials have excellent physical properties and small volume, which can increase the performance of the circuit and save circuit area.

[0131] Annealing is a kind of heating treatment process, which is to heat the material to a certain temperature and keep it for a period of time, and then slowly cool it down. Through annealing, the crystal quality of the material can be improved, the stress can be eliminated, and the bonding between layers can be promoted.

[0132] In this way, through the annealing process, the interface quality between the three layers of two-dimensional semiconductor materials is improved, so that they form a firm and high-quality bonding interface through van der Waals force.

[0133] In some embodiments, the first layer of two-dimensional semiconductor material is molybdenum disulfide (MoS2), the second layer of two-dimensional semiconductor material is rhenium disulfide (MoSe2), and the third layer of two-dimensional semiconductor material is chromium diselenide (CrSe2).

[0134] Here, an example of two-dimensional semiconductor material is provided, through the application of the above three two-dimensional semiconductor materials, MoS2, MoSe2 and CrSe2 as different layers, respectively, to optimize the performance of the device through their unique electronic, optical and material properties. It should be noted that the above is only one example, and in actual application, other two-dimensional semiconductor materials can also be used for each layer, as long as the above band width and conduction band relationship is met, and the specific material used here is not limited.

[0135] In an example, for the voltage controller circuit, the energy band structure when the three two-dimensional semiconductor materials applied to form a heterojunction is as shown in Figure 5 The band width of the first layer of two-dimensional semiconductor material is the largest, the band width of the second layer of two-dimensional semiconductor material is in the middle, and the band width of the third layer of two-dimensional semiconductor material is the smallest. Specifically, the conduction band of the first layer of two-dimensional semiconductor material is at the top, the conduction band of the second layer of two-dimensional semiconductor material is in the middle, and the conduction band of the third layer of two-dimensional semiconductor material is at the bottom. The valence band of the first layer of two-dimensional semiconductor material is at the bottom, the valence band of the second layer of two-dimensional semiconductor material is in the middle, and the valence band of the third layer of two-dimensional semiconductor material is at the top.

[0136] As shown in Figure 6 A specific example of two-dimensional material heterojunction energy band structure in a voltage controller is provided, in which the first layer of two-dimensional semiconductor material is molybdenum disulfide, the conduction band is -4.25 eV, and the valence band is -5.91 eV; the second layer of two-dimensional semiconductor material is rhenium disulfide, the conduction band is -4.46 eV, and the valence band is -5.78 eV; the first layer of two-dimensional semiconductor material is chromium diselenide, the conduction band is -4.56 eV, and the valence band is -5.27 eV. eV represents electron volts, which is the unit of energy level.

[0137] In some embodiments, the voltage controller is configured to control the state of the first switch and the second switch according to the first voltage and the second voltage, and the state is open or closed.

[0138] The voltage controller generates different control voltages in different states.

[0139] Here, the first switch and the second switch are switching elements for controlling the current flow between the two electrodes, and the on state of the circuit is adjusted by the opening (turning on) or closing (turning off) of the switches.

[0140] As shown in the example Figure 3 , one end of switch 1 (equivalent to the first switch) is connected to electrode 1, one end of switch 2 (equivalent to the second switch) is connected to electrode 2, and the other end of switch 1 and the other end of switch 2 are both connected to the source electrode. Through this connection relationship, switch 1 and switch 2 can control the conduction in different cases.

[0141] In some embodiments, if the first switch and the second switch are both open, the source electrode, the drain electrode, the gate electrode are powered on, and the source electrode and the drain electrode generate a control voltage with a first voltage value;

[0142] If the first switch is closed and the second switch is open, the source electrode, the first electrode, the drain electrode, and the gate electrode are powered on, and the source electrode and the drain electrode generate a control voltage with a second voltage value; the second voltage value is greater than the first voltage value; the size of the second voltage value is proportional to the duration of the first switch being continuously closed;

[0143] If the first switch is open and the second switch is closed, the source electrode, the second electrode, the drain electrode, and the gate electrode are powered on, and the source electrode and the drain electrode generate a control voltage with a third voltage value, the third voltage value is less than the first voltage value; the size of the third voltage value is proportional to the duration of the second switch being continuously closed.

[0144] Here, the conduction in different cases and the generated control voltage are described in conjunction with Figure 3 and Figure 4 .

[0145] (1) When the first switch (such as switch 1 as shown in Figure 3 ) and the second switch (such as switch 2 as shown in Figure 3 ) are both open, the source electrode, the drain electrode, and the gate electrode are powered on.

[0146] The electrons and holes in the second layer of two-dimensional semiconductor material are excited to start moving, and due to the bandwidth and energy band arrangement, a small amount of electrons and holes in the second layer of two-dimensional semiconductor material will transfer to the third layer of two-dimensional semiconductor material, and the remaining majority of electrons and holes in the second layer of two-dimensional semiconductor material will move in the layer.

[0147] At this time, the second layer of two-dimensional semiconductor material between the source and the drain is turned on, playing the role of a conductive layer, and a stable control voltage between the source and the drain, denoted as Vctrl-middle, is output from the drain to the voltage-controlled oscillator.

[0148] (2) When the first switch is closed and the second switch is open, the source, the first electrode, the drain, and the gate are powered on.

[0149] The electrons and holes in the second layer of two-dimensional semiconductor material are excited to start moving. Due to the bandwidth and energy band arrangement, a small amount of the electrons and holes in the second layer of two-dimensional semiconductor material will transfer to the third layer of two-dimensional semiconductor material, and the rest of the electrons and holes in the second layer of two-dimensional semiconductor material will move in the layer. The electrons and holes in the first layer of two-dimensional semiconductor material are excited to start moving. Due to the bandwidth and energy band arrangement, most of the electrons and holes in the first layer of two-dimensional semiconductor material will transfer to the second layer of two-dimensional semiconductor material, and the number of the electrons and holes in the second layer of two-dimensional semiconductor material will increase.

[0150] At this time, the second layer of two-dimensional semiconductor material between the source and the drain is turned on, playing the role of a conductive layer, and a control voltage between the source and the drain, denoted as Vctrl-max, which is greater than Vctrl-middle, is output from the drain to the voltage-controlled oscillator, and the size of Vctrl-max is in proportional relationship with the time t1 during which the first switch is continuously closed.

[0151] (3) When the first switch is open and the second switch is closed, the source, the second electrode, the drain, and the gate are powered on.

[0152] The electrons and holes in the second layer of two-dimensional semiconductor material are excited to start moving, and the electrons and holes in the third layer of two-dimensional semiconductor material are also excited to start moving. Due to the bandwidth, energy band arrangement, and the third layer being powered on, the electrons and holes excited by the third layer will attract the electrons and holes in the second layer to flow to the third layer of two-dimensional semiconductor material, so a large part of the electrons and holes in the second layer of two-dimensional semiconductor material will transfer to the third layer of two-dimensional semiconductor material, and the rest of the electrons and holes in the second layer of two-dimensional semiconductor material will move in the layer.

[0153] At this time, the second layer of two-dimensional semiconductor material between the source and the drain is turned on, playing the role of a conductive layer, and a control voltage between the source and the drain, denoted as Vctrl-min, which is less than Vctrl-middle, is output from the drain to the voltage-controlled oscillator, and the size of Vctrl-min is in proportional relationship with the time t2 during which the second switch is continuously closed.

[0154] Here, the relationship between Vctrl-min, Vctrl-middle, and Vctrl-max can be as follows: Figure 8As shown, wherein t1 represents the time when the first switch is continuously closed, and t2 represents the time when the second switch is continuously closed.

[0155] By the phase-locked loop circuit provided by the embodiment of the present application, the first voltage and the second voltage output by the frequency discriminator are input to the voltage controller, instead of the traditional charge pump and low-pass filter circuit, so that the frequency or phase difference information reflected by the first voltage and the second voltage is converted into a control voltage Vctrl that can change linearly. Compared with the use of the charge pump and low-pass filter circuit, the voltage controller of the embodiment of the present application only uses one type of device, i.e., a two-dimensional material transistor, and only one device, so that the voltage control can be realized, and the area of the entire phase-locked loop is effectively saved.

[0156] In addition, since the voltage controller is concentrated on one two-dimensional material transistor, the size of the two-dimensional material transistor is also small, so that the duration of the switching delay mismatch can be effectively reduced, the time limit of the voltage from the source to the drain is close to 0, the jitter of the output frequency of the subsequent voltage-controlled oscillator (VCO) is greatly reduced, the jitter and noise of the entire phase-locked loop are effectively reduced, and the performance of the entire phase-locked loop is improved.

[0157] In addition, since the voltage controller directly replaces the traditional charge pump and low-pass filter circuit, the non-linear problems such as leakage current, charge pump switching delay mismatch, charge and discharge current mismatch caused by the above-mentioned devices are also directly solved.

[0158] Figure 9 A flowchart of a control method of a phase-locked loop circuit provided by the embodiment of the present application is shown in FIG. 9. Figure 9 As shown, the phase-locked loop circuit comprises a frequency discriminator, a voltage controller, a voltage-controlled oscillator, and a frequency divider, and the control method comprises the following steps.

[0159] In step 901, the frequency discriminator receives a reference frequency signal and a feedback frequency signal, compares the phases of the reference frequency signal and the feedback frequency signal, and outputs a function of a signal phase difference, wherein the function of the signal phase difference comprises a first voltage and a second voltage.

[0160] In step 902, the voltage controller converts the function of the signal phase difference into a control voltage that changes linearly, and outputs the control voltage to the voltage-controlled oscillator.

[0161] In step 903, the voltage-controlled oscillator receives the control voltage and generates an output signal that has a corresponding relationship with the control voltage.

[0162] In step 904, the frequency divider divides the output signal of the voltage-controlled oscillator to obtain a feedback frequency signal, and outputs the feedback frequency signal to the frequency discriminator.

[0163] In some embodiments, the phase-locked loop circuit can employ the circuit structure shown above Figure 2 , and the voltage controller can employ the structure shown above Figure 3 .

[0164] In some embodiments, the outputting a function of the phase difference between the reference frequency signal and the feedback frequency signal includes:

[0165] If the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase of the reference frequency signal is the same as the phase of the feedback frequency signal, both the first voltage and the second voltage output by the phase-frequency detector are low;

[0166] If the frequency of the reference frequency signal is greater than the frequency of the feedback frequency signal, or the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase of the reference frequency signal leads the phase of the feedback frequency signal, the first voltage output by the phase-frequency detector is high, the second voltage is low, and the duration of the first voltage is proportional to the phase difference between the reference frequency signal and the feedback frequency signal;

[0167] If the frequency of the reference frequency signal is less than the frequency of the feedback frequency signal, or the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase of the reference frequency signal lags the phase of the feedback frequency signal, the first voltage output by the phase-frequency detector is low, the second voltage is high, and the duration of the second voltage is proportional to the phase difference between the reference frequency signal and the feedback frequency signal.

[0168] In some embodiments, the voltage controller converts the function of the phase difference between the reference frequency signal and the feedback frequency signal into a linearly changing control voltage, including:

[0169] If both the first voltage and the second voltage are low, the first switch and the second switch of the voltage controller are both open, generating a control voltage with a voltage value of a first voltage value;

[0170] If the first voltage is high and the second voltage is low, the first switch of the voltage controller is closed and the second switch is open, generating a control voltage with a voltage value of a second voltage value; the second voltage value is greater than the first voltage value; the magnitude of the second voltage value is proportional to the duration of the first switch being closed;

[0171] If the first voltage is low and the second voltage is high, the first switch of the voltage controller is open and the second switch is closed, a control voltage with a third voltage value is generated, the third voltage value is less than the first voltage value, and the third voltage value is proportional to the duration of the second switch being closed.

[0172] In some embodiments, the voltage-controlled oscillator receives the control voltage and generates an output signal corresponding to the control voltage, including:

[0173] If the control voltage received has a first voltage value, the voltage-controlled oscillator generates an output signal with a first frequency.

[0174] If the control voltage received has a second voltage value, the voltage-controlled oscillator generates an output signal with a second frequency.

[0175] If the control voltage received has a third voltage value, the voltage-controlled oscillator generates an output signal with a third frequency.

[0176] The second frequency is greater than the first frequency, and the first frequency is greater than the third frequency.

[0177] Here, the logic of the phase frequency detector and the voltage controller of the phase-locked loop circuit under different conditions is provided. Here, three conditions are taken as examples, i.e., the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase is the same, the phase is ahead, and the phase is behind. The logic of the phase frequency detector is as shown in Figure 7 , and the logic of the voltage controller is as shown in Figure 8 , and the specific conditions are as follows:

[0178] (1) When the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase of the reference frequency signal is the same as the phase of the feedback frequency signal, as shown in (a) of Figure 7 , the UP signal (equivalent to the first voltage) and the DOWN signal (equivalent to the second voltage) output by the phase frequency detector are both low, and the voltage difference between the UP signal and the DOWN signal is 0. According to the voltage difference between the UP signal and the DOWN signal, switch 1 and switch 2 are both open, and the output voltage Vctrl generated by the voltage controller is Vctrl-middle. Correspondingly, the frequency of the entire voltage-controlled oscillator (VCO) is frequency-middle.

[0179] (2) When the frequency of the reference frequency signal is greater than the frequency of the feedback frequency signal, and the phase of the reference frequency signal is ahead of the feedback frequency signal, as shown in Figure 7As shown in (b) of FIG. 1, the UP signal outputted by the phase-frequency detector is high level and the maintaining time of the high level is proportional to the phase difference between the reference frequency signal and the feedback frequency signal, the DOWN signal is low level, and the voltage difference between the UP signal and the DOWN signal is positive. According to the voltage difference between the UP signal and the DOWN signal, switch 1 is closed and switch 2 is opened, and the output voltage Vctrl generated by the voltage controller is Vctrl-max, the size of which is proportional to the time t1 during which switch 1 is closed. Correspondingly, the frequency generated by the voltage-controlled oscillator is frequency-max.

[0180] (3) When the frequency of the reference frequency signal is less than the frequency of the feedback frequency signal and the phase of the reference frequency signal lags behind the feedback frequency signal, as shown in (c) of FIG. 1, the UP signal outputted by the phase-frequency detector is low level, the DOWN signal is high level and the maintaining time of the high level is proportional to the phase difference between the reference frequency signal and the feedback frequency signal, and the voltage difference between the UP signal and the DOWN signal is negative. According to the voltage difference between the UP signal and the DOWN signal, switch 1 is opened and switch 2 is closed, and the output voltage Vctrl generated by the voltage controller is Vctrl-min, the size of which is proportional to the time t2 during which switch 2 is closed. Correspondingly, the frequency generated by the voltage-controlled oscillator is frequency-min. Figure 7

[0181] The above frequency-max>frequency-middle>frequency-min.

[0182] In some embodiments, the voltage controller comprises: a source, a drain, a gate, a first electrode, a second electrode, a first switch, a second switch, a first layer of two-dimensional semiconductor material, a second layer of two-dimensional semiconductor material, a third layer of two-dimensional semiconductor material.

[0183] The second layer of two-dimensional semiconductor material and the second electrode are located on the third layer of two-dimensional semiconductor material, and the second electrode is located in the first direction of the second layer of two-dimensional semiconductor material.

[0184] The source, the drain and the first layer of two-dimensional semiconductor material are located on the second layer of two-dimensional semiconductor material, and the source is located in the first direction of the first layer of two-dimensional semiconductor material and the drain is located in the second direction of the first layer of two-dimensional semiconductor material.

[0185] The first electrode and the gate are located on the first layer of two-dimensional semiconductor material, and the first electrode is located in the first direction of the gate, and the gate is located between the first electrode and the drain.

[0186] ​One end of the first switch is connected to the first electrode, one end of the second switch is connected to the second electrode, and the other end of the first switch and the other end of the second switch are both connected to the source electrode.

[0187] In some embodiments, the voltage controller further comprises: an insulating layer, a substrate;

[0188] The insulating layer is used to isolate different electrodes and materials.

[0189] The substrate is used to provide a stable carrier for the voltage controller.

[0190] In some embodiments, the insulating layer is used to isolate the second electrode and the source electrode, isolate the source electrode and the first electrode, isolate the first electrode and the drain electrode, and isolate the gate electrode and the first layer of two-dimensional semiconductor material.

[0191] In some embodiments, the source electrode receives a source voltage input from an external power source to generate a current.

[0192] The gate electrode receives a gate voltage input from an external power source to regulate the conductive layer, which includes the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material, which are used to provide materials for generating electrons and holes.

[0193] The drain electrode is used to output the control voltage.

[0194] The first switch and the second switch are used to control the on-off of the first electrode and the second electrode, respectively.

[0195] In some embodiments, the bandwidth of the first layer of two-dimensional semiconductor material is greater than that of the second layer of two-dimensional semiconductor material, and the bandwidth of the second layer of two-dimensional semiconductor material is greater than that of the third layer of two-dimensional semiconductor material.

[0196] In some embodiments, the conduction band of the first layer of two-dimensional semiconductor material is at the top, the conduction band of the second layer of two-dimensional semiconductor material is in the middle, and the conduction band of the third layer of two-dimensional semiconductor material is at the bottom.

[0197] The valence band of the first layer of two-dimensional semiconductor material is at the bottom, the valence band of the second layer of two-dimensional semiconductor material is in the middle, and the valence band of the third layer of two-dimensional semiconductor material is at the top.

[0198] In some embodiments, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material form a heterojunction to regulate the electron and hole transport behavior of different layers of two-dimensional semiconductor material.

[0199] In some embodiments, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material are combined by Van der Waals force.

[0200] In some embodiments, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material are annealed to form Van der Waals interface between the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material when the heterojunction is prepared.

[0201] In some embodiments, the first layer of two-dimensional semiconductor material is molybdenum disulfide, the second layer of two-dimensional semiconductor material is rhenium disulfide, and the third layer of two-dimensional semiconductor material is chromium diselenide.

[0202] In some embodiments, the voltage controller is configured to control the state of the first switch and the second switch according to the first voltage and the second voltage, the state being open or closed.

[0203] In some embodiments, the voltage controller generates different control voltages in different states.

[0204] In some embodiments, if the first switch and the second switch are both open, the source electrode, the drain electrode, the gate electrode are powered on, and the source electrode and the drain electrode generate a control voltage with a first voltage value.

[0205] If the first switch is closed and the second switch is open, the source electrode, the first electrode, the drain electrode, and the gate electrode are powered on, and the source electrode and the drain electrode generate a control voltage with a second voltage value; the second voltage value is greater than the first voltage value; the magnitude of the second voltage value is proportional to the duration of the first switch being closed.

[0206] If the first switch is open and the second switch is closed, the source electrode, the second electrode, the drain electrode, and the gate electrode are powered on, and the source electrode and the drain electrode generate a control voltage with a third voltage value; the third voltage value is less than the first voltage value; the magnitude of the third voltage value is proportional to the duration of the second switch being closed.

[0207] The specific structure of the phase-locked loop circuit can refer to Figures 2 to 6 The relevant description is not repeated here.

[0208] It should be understood that the steps shown above can be reordered, added or deleted. For example, the steps described in this application can be executed in parallel, in sequence or in different order, as long as the desired results of the technical solutions disclosed in this application can be achieved, and this application does not limit this.

[0209] In the above description, reference is made to "some embodiments", which describe a subset of all possible embodiments, but it is understood that "some embodiments" can be the same subset or a different subset of all possible embodiments, and can be combined with each other without conflict.

[0210] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing the embodiments of the application only and is not intended to be limiting of the application.

[0211] It should be understood that, in various embodiments of the present application, the sequence of the implementation procedures does not mean the order of execution, and the execution order of the procedures should be determined according to their functions and inherent logic, and should not constitute any limitation on the implementation procedures of the embodiments of the present application.

[0212] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0213] The above description is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A phase-locked loop circuit, characterized by comprising: The phase-locked loop circuit comprises a frequency discriminator, a voltage controller, a voltage-controlled oscillator, and a frequency divider. The frequency discriminator is configured to receive a reference frequency signal and a feedback frequency signal, compare phases of the reference frequency signal and the feedback frequency signal, and output a function of a signal phase difference, wherein the function of the signal phase difference comprises a first voltage and a second voltage. The voltage controller is configured to convert the function of the signal phase difference into a linearly changing control voltage, and output the control voltage to the voltage-controlled oscillator. The voltage-controlled oscillator is configured to receive the control voltage and generate an output signal corresponding to the control voltage. The frequency divider is configured to divide the output signal of the voltage-controlled oscillator to obtain the feedback frequency signal, and output the feedback frequency signal to the frequency discriminator. The voltage controller comprises a source electrode, a drain electrode, a gate electrode, a first electrode, a second electrode, a first switch, a second switch, a first layer of two-dimensional semiconductor material, a second layer of two-dimensional semiconductor material, and a third layer of two-dimensional semiconductor material. The second layer of two-dimensional semiconductor material and the second electrode are located on the third layer of two-dimensional semiconductor material, and the second electrode is located in a first direction of the second layer of two-dimensional semiconductor material. The source electrode, the drain electrode, and the first layer of two-dimensional semiconductor material are located on the second layer of two-dimensional semiconductor material, and the source electrode is located in a first direction of the first layer of two-dimensional semiconductor material, and the drain electrode is located in a second direction of the first layer of two-dimensional semiconductor material. The first electrode and the gate electrode are located on the first layer of two-dimensional semiconductor material, and the first electrode is located in a first direction of the gate electrode, and the gate electrode is located between the first electrode and the drain electrode. One end of the first switch is connected to the first electrode, one end of the second switch is connected to the second electrode, and the other end of the first switch and the other end of the second switch are both connected to the source electrode.

2. The circuit of claim 1, wherein, The voltage controller further comprises an insulating layer and a substrate. The insulating layer is configured to isolate different electrodes and materials. The substrate is configured to provide a stable carrier for the voltage controller.

3. The circuit of claim 2, wherein, The insulating layer is configured to isolate the second electrode and the source electrode, isolate the source electrode and the first electrode, isolate the first electrode and the drain electrode, and isolate the gate electrode and the first layer of two-dimensional semiconductor material.

4. The circuit of claim 1, wherein, The source electrode receives a source voltage input by an external power supply and is configured to generate a current. The gate electrode receives a gate voltage input by an external power supply and is configured to regulate a conductive layer. The conductive layer comprises the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material, and the third layer of two-dimensional semiconductor material, and is configured to provide materials for generating electrons and holes. The drain electrode is configured to output the control voltage. The first switch and the second switch are respectively configured to control the on-off of the first electrode and the second electrode.

5. The circuit of claim 1 or 4, wherein The bandwidth of the first layer of two-dimensional semiconductor material is greater than the bandwidth of the second layer of two-dimensional semiconductor material, and the bandwidth of the second layer of two-dimensional semiconductor material is greater than the bandwidth of the third layer of two-dimensional semiconductor material.

6. The circuit of claim 1 or 4, wherein The conduction band of the first layer of two-dimensional semiconductor material is at the top, the conduction band of the second layer of two-dimensional semiconductor material is in the middle, and the conduction band of the third layer of two-dimensional semiconductor material is at the bottom. The valence band of the first layer of two-dimensional semiconductor material is at the bottom, the valence band of the second layer of two-dimensional semiconductor material is in the middle, and the valence band of the third layer of two-dimensional semiconductor material is at the top.

7. The circuit of claim 1 or 4, wherein The first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material form a heterojunction for regulating the electron and hole transport behaviors of different layers of two-dimensional semiconductor materials.

8. The circuit of claim 1 or 4, wherein, The first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material are combined by van der Waals force.

9. The circuit of claim 7, wherein, In the preparation of the heterojunction, the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material are subjected to annealing treatment to form a van der Waals interface between the first layer of two-dimensional semiconductor material, the second layer of two-dimensional semiconductor material and the third layer of two-dimensional semiconductor material.

10. The circuit of claim 1 or 4, wherein, The first layer of two-dimensional semiconductor material is molybdenum disulfide, the second layer of two-dimensional semiconductor material is rhenium disulfide, and the third layer of two-dimensional semiconductor material is chromium diselenide.

11. The circuit of claim 1, wherein, The voltage controller is configured to control states of the first switch and the second switch according to the first voltage and the second voltage, the states being open or closed. The voltage controller generates different control voltages in different states.

12. The circuit of claim 11, wherein, If the first switch and the second switch are both open, the source, the drain, the gate are powered on, and the source and the drain generate a control voltage with a first voltage value. If the first switch is closed and the second switch is open, the source, the first electrode, the drain, and the gate are powered on, and the source and the drain generate a control voltage with a second voltage value; the second voltage value is greater than the first voltage value. The magnitude of the second voltage value is proportional to the duration of the continuous closing of the first switch. If the first switch is open and the second switch is closed, the source, the second electrode, the drain, and the gate are powered on, and the source and the drain generate a control voltage with a third voltage value; the third voltage value is less than the first voltage value. The magnitude of the third voltage value is proportional to the duration of the continuous closing of the second switch.

13. A control method of a phase-locked loop circuit, characterized by, The method is applied to the phase-locked loop circuit of claim 1, and the method comprises: The frequency discriminator receives a reference frequency signal and a feedback frequency signal, and outputs a function of a signal phase difference by comparing phases of the reference frequency signal and the feedback frequency signal; the function of the signal phase difference comprises a first voltage and a second voltage; The voltage controller converts the function of the signal phase difference into a linearly changing control voltage, and outputs the control voltage to the voltage-controlled oscillator; The voltage-controlled oscillator receives the control voltage and generates an output signal corresponding to the control voltage; The frequency divider divides the output signal of the voltage-controlled oscillator to obtain the feedback frequency signal, and outputs the feedback frequency signal to the frequency discriminator.

14. The method of claim 13, wherein, The function of outputting signal phase difference by comparing the phase of the reference frequency signal and the feedback frequency signal comprises: If the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal, and the phase of the reference frequency signal is the same as the phase of the feedback frequency signal, the first voltage and the second voltage output by the phase frequency detector are both low level; If the frequency of the reference frequency signal is greater than the frequency of the feedback frequency signal, or the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal and the phase of the reference frequency signal is ahead of the phase of the feedback frequency signal, the first voltage output by the phase frequency detector is high level, the second voltage is low level, and the maintaining time of the first voltage is proportional to the phase difference between the reference frequency signal and the feedback frequency signal; If the frequency of the reference frequency signal is less than the frequency of the feedback frequency signal, or the frequency of the reference frequency signal is equal to the frequency of the feedback frequency signal and the phase of the reference frequency signal is behind the phase of the feedback frequency signal, the first voltage output by the phase frequency detector is low level, the second voltage is high level, and the maintaining time of the second voltage is proportional to the phase difference between the reference frequency signal and the feedback frequency signal; Correspondingly, the function of signal phase difference is converted into linearly changing control voltage by the voltage controller, comprising: The first switch and the second switch of the voltage controller are both disconnected, generating the control voltage with the first voltage value; The first switch of the voltage controller is closed, and the second switch is disconnected, generating the control voltage with the second voltage value; the second voltage value is greater than the first voltage value; the size of the second voltage value is proportional to the time length of the first switch being closed continuously; The first switch of the voltage controller is disconnected, and the second switch is closed, generating the control voltage with the third voltage value; the third voltage value is less than the first voltage value; the size of the third voltage value is proportional to the time length of the second switch being closed continuously.

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