Phase modulation amplification circuit and reference frequency source

Abstract

The invention provides a phase modulation amplifying circuit and a reference frequency source, and relates to the technical field of high-frequency driving circuits. The phase modulation amplification circuit comprises a phase shifter which comprises a first input end and a first output end, the first input end is used for inputting a first voltage, the first output end is used for outputting a second voltage, and the second voltage is the voltage after phase shift of the first voltage; wherein the first voltage is the voltage generated after the initial signal is amplified; the processing circuit comprises a first transistor and a second transistor, the source electrode of the first transistor is connected with the drain electrode of the second transistor, the grid electrode of the first transistor receives the second voltage, and the grid electrode of the second transistor receives the third voltage; based on the nonlinear effect of the first transistor and the second transistor, a frequency mixing signal of the second voltage and the third voltage is determined, and the frequency mixing signal comprises a frequency combining signal and a difference frequency signal; the third voltage is the voltage generated after the input signal is amplified, and the phase of the third voltage is synchronous with the phase of the initial signal.

Description

Technical Field

[0001] The present disclosure relates to the technical field of high-frequency driving circuits, and more specifically, to a phase modulation amplifier circuit and a reference frequency source. Background Art

[0002] In the measurement and control circuits of superconducting and silicon spin quantum computers, high-performance C-band and even millimeter-wave frequency synthesizers are required. In order to reduce the in-band phase noise of the frequency synthesizer, the frequency division ratio of the phase-locked loop should be as small as possible, which requires the use of a high-frequency reference frequency source.

[0003] The frequency of traditional quartz crystal oscillators is generally below 100MHz, which cannot effectively meet the urgent needs of high-performance measurement and control circuits for quantum computers. Radiating contour MEMS (Micro-Electro-Mechanical Systems, MEMS) disk resonators with high-frequency and high-Q characteristics are considered ideal solutions because they can provide the required high-frequency reference signals. However, due to the use of a capacitive transduction mechanism, this type of resonator has a large modal resistance, which is in the order of hundreds of KΩ or even MΩ. In order to compensate for the huge insertion loss of the resonator, the peripheral drive circuit requires a very high transimpedance gain, and at the same time requires the circuit to have a phase shift of about 0 degrees at the resonant frequency to meet the positive feedback conditions of the oscillator. Generally, the goal of a phase shift of 0 degrees is achieved by setting the bandwidth of the drive circuit to 10 times or more of the resonant frequency. However, this is difficult to achieve for high-frequency (>100MHz) resonators. This is because achieving ultra-high gain and high bandwidth at the same time violates the basic circuit rules. Even if it is achieved, the circuit is very prone to self-excitation. Therefore, it is urgent to find a high-performance drive circuit solution that can work stably. Summary of the invention

[0004] In view of this, the present disclosure provides a phase modulation amplifier circuit and a reference frequency source.

[0005] On the one hand, the present disclosure provides a phase-modulation amplifier circuit, including: a phase shifter, including a first input terminal and a first output terminal, the first input terminal is used to input a first voltage, the first output terminal is used to output a second voltage, and the second voltage is a voltage after the first voltage is phase-shifted; wherein the first voltage is a voltage generated after the initial signal is amplified; a processing circuit, including a first transistor and a second transistor, the source of the first transistor is connected to the drain of the second transistor, the gate of the first transistor receives the second voltage, and the gate of the second transistor receives a third voltage; based on the nonlinear effect of the first transistor and the second transistor, a mixing signal of the second voltage and the third voltage is determined, and the mixing signal includes a combined frequency signal and a difference frequency signal; wherein the third voltage is a voltage generated after the input signal is amplified, and the phase of the third voltage is synchronized with the phase of the initial signal.

[0006] According to an embodiment of the present disclosure, the processing circuit further includes: a filter, an input end of which is connected to the first input end and the drain of the second transistor, and the filter is used to output a difference frequency signal.

[0007] According to an embodiment of the present disclosure, the phase shifter includes: a capacitor, one end of which is input with a first voltage; a third transistor, a drain of which is connected to the other end of the capacitor and the gate of the first transistor, and a gate of which is connected to the output end of the filter; based on the difference frequency signal, the on-resistance value of the third transistor is adjusted to synchronize the phases of the second voltage and the third voltage.

[0008] According to an embodiment of the present disclosure, it also includes: a first branch for amplifying the initial signal to generate a first voltage; and a second branch for amplifying the initial signal to generate a third voltage.

[0009] According to an embodiment of the present disclosure, the initial signal is a current signal, and the first branch includes: a first amplifier, used to amplify the current signal to generate a first voltage; an isolation circuit, connected to the first amplifier and the phase shifter, used to isolate the parasitic capacitance of the phase shifter.

[0010] According to an embodiment of the present disclosure, the first amplifier includes a circuit structure with gate voltage feedback, and the circuit structure with gate voltage feedback is used to reduce the resistance value of the current signal.

[0011] According to an embodiment of the present disclosure, the isolation circuit includes: a fourth transistor, whose gate is connected to the output end of the first amplifier; and a first resistor, one end of which is connected to the source of the fourth transistor and the other end is grounded.

[0012] According to an embodiment of the present disclosure, the second branch includes: a second amplifier for generating a fourth voltage after performing a first-stage amplification on the current signal; and a third amplifier for generating a third voltage after performing a second-stage amplification on the fourth voltage.

[0013] A second aspect of the present disclosure provides a reference frequency source, including: a resonator, used to generate a frequency signal; and a phase-modulation amplifier circuit, used to amplify the frequency signal and then output it.

[0014] According to an embodiment of the present disclosure, the output mode includes single-ended output or differential output.

[0015] The phase modulation amplifier circuit and reference frequency source provided by the embodiments of the present disclosure have at least the following beneficial effects:

[0016] The processing circuit includes two transistors. By utilizing the nonlinear effect of the two transistors, the mixed signal of the two input voltages can be simply and directly determined, wherein the mixed signal includes a summed frequency signal and a difference frequency signal. The mixer structure in the processing circuit structure of this embodiment is simpler, and can quickly determine the mixed signal of the two input voltages, and then determine the difference frequency signal. And according to the difference frequency signal, the on-resistance of the phase shifter transistor is adjusted, and then the time constant of the phase shifter is adjusted, and the leading phase compensation amount introduced by the phase shifter is changed accordingly, thereby realizing the adaptive phase modulation function of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0018] Figure 1 The existing ultra-high gain broadband circuit is schematically shown;

[0019] Figure 2 A system framework diagram of a phase modulation amplifier circuit according to an embodiment of the present disclosure is schematically shown;

[0020] Figure 3 A phase modulation amplifier circuit diagram according to an embodiment of the present disclosure is schematically shown;

[0021] Figure 4 A processing circuit diagram according to an embodiment of the present disclosure is schematically shown;

[0022] Figure 5 The circuit diagram of the RGC transimpedance amplifier according to an embodiment of the present disclosure is schematically shown;

[0023] Figure 6 A schematic diagram of a Cherry-Hooper broadband amplifier circuit according to an embodiment of the present disclosure is shown;

[0024] Figure 7 A time domain diagram schematically shows the effect of adjusting the voltage phase of a key node according to an embodiment of the present disclosure;

[0025] Figure 8 A time domain diagram schematically shows the effect of adjusting the voltage phase of a key node according to an embodiment of the present disclosure;

[0026] Fig. 9 A system framework diagram of a reference frequency source according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known systems and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0028] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0029] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0030] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0031] Figure 1 An existing ultra-high gain broadband circuit is schematically shown.

[0032] like Figure 1 As shown, the ultra-high gain broadband circuit includes a gain branch 110, a reference branch 120 and an adaptive loop 130. The adaptive loop 130 includes a tunable phase shifter and a charge pump phase-locked loop adaptive phase control circuit. The gain branch 110 is composed of a narrowband transimpedance amplifier; the reference branch 120 is composed of a broadband transimpedance amplifier and a Cherry-Hooper broadband amplifier.

[0033] In order to improve the gain, the gain branch 110 sets the upper limit frequency at the resonant frequency of the MEMS resonator by sacrificing the bandwidth to achieve a gain increase of about 10 times. At the same time, the approximately -45 degree lagging phase shift introduced by the transimpedance amplifier in the gain branch 110 is compensated by the tunable phase shifter, and the compensation amount of the phase shifter is determined by the control voltage V of the charge pump phase-locked loop adaptive phase control circuit. crtl Real-time adjustment.

[0034] The voltage signal without phase lag output by the reference branch 120 is used as the reference signal of the phase-locked loop. The phase-locked loop calculates the voltage phase difference between the two branches through a phase frequency detector (PFD) and inputs it into the charge pump (CP) to output a control voltage signal V crtl By inputting this control voltage signal to the gate of the MOS tube in the phase shifter, the gate voltage V of the MOS tube is adjusted in real time through a closed loop. ctrl , the drain-source resistance of the MOS tube can be dynamically adjusted, thereby changing the RC value of the phase shifter and realizing real-time compensation of the phase.

[0035] However, in the process of implementing the present disclosure, it is found that the above technical solution has the following problems:

[0036] (1) The adaptive loop needs to ensure that the phase shifter output voltage is in phase with the reference voltage. The design of the phase-locked loop needs to meet the requirements of normal function and broadband characteristics at the same time. That is, the phase-locked method used by the phase-locked loop is complex, and the phase-locked circuit structure is complex, which brings new challenges to design and debugging.

[0037] (2) The way the frequency detector and phase detector calculate the voltage phase difference is complex. At the same time, when the input phase difference is converted into a control voltage signal through a charge pump, the control voltage jumps between 0-1.8V due to the high impedance node of the charge pump. The output control voltage is unstable and the phase cannot be accurately compensated.

[0038] Based on this, the embodiment of the present disclosure provides a more concise implementation scheme. Figure 2-Figure 8 Provide explanation.

[0039] Figure 2 The system framework diagram of the phase modulation amplifier circuit according to the embodiment of the present disclosure is schematically shown.

[0040] Figure 3 A phase modulation amplifier circuit diagram according to an embodiment of the present disclosure is schematically shown.

[0041] Figure 4 The figure schematically shows a processing circuit diagram according to an embodiment of the present disclosure.

[0042] like Figure 2 and Figure 3 As shown, a phase modulation amplifier circuit includes an adaptive loop 230. The adaptive loop 230 may include a phase shifter 231 and a processing circuit 232.

[0043] The phase shifter 231 includes a first input terminal and a first output terminal. The first input terminal is used to input a first voltage V O1The first output terminal is used to output a second voltage, and the second voltage is a voltage after the first voltage is phase-shifted; wherein the first voltage is a voltage generated after the initial signal is amplified.

[0044] like Figure 4 As shown, the processing circuit 232 includes a first transistor M12 and a second transistor M13. The source of the first transistor M12 is connected to the drain of the second transistor M13, and the source of the second transistor M13 is grounded. The gate of the first transistor M12 receives the second voltage, and the gate of the second transistor M13 receives the third voltage V REF Based on the nonlinear effect of the first transistor and the second transistor, a mixed signal of the second voltage and the third voltage is determined, and the mixed signal includes a combined frequency signal and a difference frequency signal. REF is the voltage generated after the initial signal is amplified, and the third voltage V REF The phase of the initial signal is synchronized with the phase of the initial signal and can be used as the first voltage V O1 The reference voltage.

[0045] For example, in the phase modulation amplifier circuit, the processing circuit 232 sets the first transistor M12 and the second transistor M13 to utilize the nonlinear effect of the two transistors to convert the input second voltage such as V in1 , the third voltage is V in2 Mixing is performed to generate a sum frequency signal and a difference frequency signal, such as

[0046] .

[0047] .

[0048] Among them, A1 and A2 are amplitudes, ,and is the frequency, and For phase.

[0049] The second voltage Vin1 and the third voltage Vin2 are mixed to output Vout, and the expression of Vout is as follows:

[0050] .

[0051] Among them, the difference frequency signal is , the combined frequency signal is , since the second voltage V in1 and the third voltage V in2 The frequency is the same, that is , the difference frequency signal is .

[0052] In the embodiment of the present disclosure, by setting the first transistor M12 and the second transistor M13 in the above-mentioned processing circuit, the mixed signal of the two input voltage signals can be quickly and directly calculated. Compared with the existing method of using a phase-locked loop module to determine the phase difference and then using a charge pump to convert the phase difference into a control voltage, the circuit structure of this embodiment is simpler, and a DC component related to the phase difference can be directly output, and it will not change rapidly over time, which can provide a basis for a stable control voltage.

[0053] In some embodiments, the processing circuit 232 further includes a resistor R14 , one end of the resistor R14 is connected to the drain of the first transistor M12 , and the other end of the resistor R14 is connected to the voltage source VDD.

[0054] like Figure 4 As shown, in some embodiments, the processing circuit 232 further includes: a filter, whose input terminal is connected to the first input terminal and the drain of the second transistor, and the filter is used to output the difference frequency signal.

[0055] In some embodiments, the filter may include a resistor R15 and a capacitor C6. One end of the resistor R15 is connected to the drain of the first transistor M12, the other end of the resistor R15 is connected to one end of the capacitor C6, and the other end of the capacitor C6 is grounded.

[0056] The low-pass filter composed of resistor R15 and capacitor C6 can directly filter out the combined frequency signal in the mixed signal to output the difference frequency signal. .

[0057] According to an embodiment of the present disclosure, the phase shifter 231 includes: a capacitor C1 and a third transistor M4. The capacitor C1 has one end inputted with a first voltage V O1 The third transistor M4 has a drain connected to the other end of the capacitor C1 and the gate of the first transistor M12, and a gate connected to the output end of the filter. Based on the difference frequency signal, the phase difference between the second voltage and the third voltage is obtained, and a voltage signal is output to control the gate voltage of the third transistor, thereby adjusting the on-resistance value of the third transistor M4 to synchronize the second voltage with the third voltage.

[0058] The control voltage V generated by the processing circuit 232 ctrl The gate of the transistor M4 of the input phase shifter 231 is biased in the deep linear region. The on-resistance of the transistor M4 increases with the control voltage V ctrl The phase shifter output voltage V out , that is, when the phase of the second voltage changes, the transistor M12 in the processing circuit 232 adjusts the control voltage V in real time according to the received voltage. ctrl, and then adjust the time constant of the phase shifter 231 to achieve phase compensation of the phase shifter, thereby realizing the adaptive phase modulation function of the amplifier.

[0059] like Figure 2 As shown, in the embodiment of the present disclosure, the amplifier circuit further includes: a first branch 210 and a second branch 220. The first branch 210 is used to amplify the initial signal to generate a first voltage V O1 The first branch can be used as a gain branch of the amplifier circuit. The second branch 220 is used to amplify the initial signal and generate a third voltage V REF , the second branch 220 can be used as a reference circuit of the amplifier circuit, wherein the phase of the third voltage is synchronized with the phase of the initial signal.

[0060] Based on the above embodiment, the initial signal is the current signal I in , the first branch includes: a first amplifier 211 and an isolation circuit.

[0061] The first amplifier 211 is used to convert the current signal I in After amplification, a first voltage is generated.

[0062] The isolation circuit is connected to the first amplifier and the phase shifter and is used to isolate the parasitic capacitance of the phase shifter.

[0063] Based on the above embodiment, the first amplifier includes a circuit structure with gate voltage feedback (Regulated Cascode, RGC). That is, the first amplifier can be a circuit structure of RGC, and the circuit structure of RGC can effectively reduce the input current signal I in The resistance value is adjusted to make the circuit broadband.

[0064] Figure 5 The circuit diagram of an RGC transimpedance amplifier according to an embodiment of the present disclosure is schematically shown.

[0065] like Figure 5 As shown, in some embodiments, the circuit structure of RGC is composed of a transistor M1, a transistor M2, a resistor R1, a resistor R2 and a resistor R3.

[0066] The source of transistor M1 receives the input signal I in, its drain is connected to one end of resistor R1, and its gate is connected to the drain of transistor M2. The other end of resistor R1 is connected to one end of resistor R2, and at the same time, one end of resistor R2 is connected to the voltage power supply VDD, and the other end of resistor R2 is connected to the drain of transistor M2. The source of transistor M2 is connected to one end of resistor R3 and grounded, and the other end of resistor R3 is connected to the gate of transistor M2. Through the signal amplification effect of the NMOS tube and the load resistor R1, the RGC transimpedance amplifier achieves high gain and bandwidth. The input current signal enters from the source of transistor M1, is transmitted to the load end through the inside of transistor M1, and is converted into a voltage signal V through the load resistor R1. out .

[0067] like Figure 3 As shown, according to an embodiment of the present disclosure, the isolation circuit includes: a fourth transistor M3 and a first resistor R4.

[0068] The gate of the fourth transistor M3 is connected to the output end of the first amplifier, that is, connected to the drain of the transistor M1. The drain of the fourth transistor M3 is connected to one end of the resistor R2 and the voltage power supply VDD, the source of the fourth transistor M3 is connected to one end of the first resistor R4, and the other end of the first resistor R4 is connected to the source of the transistor M2. The source of the fourth transistor M3 is connected to one end of the capacitor C1 in the phase shifter 231.

[0069] In the embodiment of the present disclosure, the isolation circuit may adopt a source follower composed of a fourth transistor M3 and a first resistor R4, which can effectively isolate the parasitic effect of the phase shifter 231 to achieve purity and stability of the output signal.

[0070] like Figure 2 As shown, according to an embodiment of the present disclosure, the second branch includes: a second amplifier 221 and a third amplifier 222 .

[0071] The second amplifier 221 is used to convert the current signal I in The third amplifier 222 is used to generate a third voltage V after performing the second stage amplification on the fourth voltage. REF .

[0072] like Figure 5 As shown, in some embodiments, the second amplifier 221 can use the RGC transimpedance amplifier of the first amplifier 211, and the gain of the fourth voltage is less than the first voltage V O1 That is, the first amplifier 211 and the second amplifier 221 can use amplifiers with the same structure, but the first amplifier 211 obtains an output signal with a higher gain, while the second amplifier 221 obtains an output signal with a larger bandwidth. The third amplifier 222 further amplifies the fourth voltage output by the second amplifier and outputs VREF .

[0073] Figure 6 The circuit diagram of a Cherry-Hooper broadband amplifier according to an embodiment of the present disclosure is schematically shown.

[0074] like Figure 6 As shown, the third amplifier 222 can adopt a Cherry-Hooper broadband amplifier. The Cherry-Hooper broadband amplifier can be composed of transistors M7-M11, resistors R7-R12 and capacitor C4. Transistors M8 and M9 form a first-stage inverting amplifier, and transistors M10 and M11 form a second-stage inverting amplifier. Resistors R9~R10 and transistor M7 are the bias circuit of the first-stage inverting amplifier, and resistors R11~R12 and capacitor C4 form the feedback circuit of the second-stage inverting amplifier, providing self-bias voltage, expanding bandwidth and improving gain. The Cherry-Hooper broadband amplifier circuit adopts current multiplexing technology to achieve low power consumption and high gain at the same time.

[0075] Specifically, the source of transistor M7 is connected to one end of resistor R9, its gate is connected to its drain, and the other end of resistor R9 is connected to the voltage power supply VDD. One end of resistor R10 is connected to one end of resistor R9 and the gate of transistor M7, and the other end of resistor R10 is grounded. Transistor M8 and transistor M9 share a gate and a drain, the source of transistor M8 is connected to the voltage power supply VDD, and the source of transistor M9 is grounded. Resistor R11 is connected in series with resistor R12, the other end of resistor R11 is connected to the drain of transistor M8, and the other end of resistor R12 is connected to the drain of transistor M10. One end of capacitor C4 is connected to one end of resistor R11, and the other end of capacitor C4 is connected to the source of transistor M9. Transistor M10 and transistor M11 share a gate and a drain, the source of transistor M10 is connected to the voltage power supply VDD, and the source of transistor M11 is grounded.

[0076] like Figure 3 As shown, in some embodiments, the first branch 210 further includes a capacitor C2 and a resistor R5 to play a role in potential clamping. One end of the capacitor C2 is connected to the drain of the transistor M4, and the other end is connected to the resistor R5. The other end of the resistor R5 is connected to the reference voltage V ref One end is connected. Reference voltage V ref The other end is connected to the source of the transistor M4.

[0077] In some embodiments, the second branch 220 further includes a capacitor C3, which is used to connect the RGC transimpedance amplifier and the Cherry-Hooper broadband amplifier and is used as an isolation capacitor. Specifically, one end of the capacitor C3 is connected to the drain of the transistor M5, and the other end is connected to the drain of the transistor M7. The capacitor C5 and the resistor R13 are also included, which also play the role of potential clamping.

[0078] Figure 7 The time domain diagram schematically shows the effect of adjusting the voltage phase of a key node according to an embodiment of the present disclosure.

[0079] In order to verify the implementation effect of the technical solution of the present disclosure, the inventors performed transient simulation of the implementation circuit of the present disclosure in Cadence design software. The simulation results are as follows: Figure 7 As shown. From top to bottom are the output voltage signals V after being amplified by the high-gain transimpedance amplifier. O1 , the final output voltage signal V out and I in The corresponding input voltage signal V in .from Figure 7 It can be seen that as the adaptive phase adjustment is completed, the measurement result at 4.7μs shows that V O1 Relative to V in There is a large phase lag, but V out Relative to V in Phase alignment is achieved, that is, phase compensation is in place.

[0080] Figure 8 The time domain diagram schematically shows the effect of adjusting the voltage phase of a key node according to an embodiment of the present disclosure.

[0081] In order to further clarify the phase adjustment effect, the inventors also performed simulations in the frequency domain, such as Figure 8 shown. Figure 8 The middle dashed line is the output voltage V after the input signal passes through the high gain transimpedance amplifier. O1 Phase frequency response diagram; the solid line is the final output voltage signal V out .Depend on Figure 8 It can be seen that the output voltage V of the transimpedance amplifier O1 Relative to the input signal, it exhibits a lagging phase shift of about -26°. Under the action of the adaptive phase modulation circuit, the final output voltage V out Compared with the input voltage, it shows almost the same phase, achieving phase compensation.

[0082] Therefore, the phase modulation amplifier circuit of the disclosed embodiment provides a specific processing circuit structure, wherein the processing circuit adopts the internal design and interface design of the dual-gate structure mixer, which provides a useful reference for ordinary technicians in the industry. At the same time, the circuit design of the dual-gate structure mixer provided by this embodiment is more streamlined than the adaptive phase-locked loop structure, the circuit implementation is easier and the compensation of the lagging phase shift of the high-gain transimpedance amplifier can be well completed. The introduced noise is lower, the parasitic is lower, and the area is smaller.

[0083] Based on the phase-modulation amplifier circuit of the above embodiment, the present disclosure further provides a reference frequency source, which has the same technical features and beneficial effects as the phase-modulation amplifier circuit of the above embodiment, and will not be described in detail here.

[0084] Fig. 9 A system framework diagram of a reference frequency source according to an embodiment of the present invention is schematically shown.

[0085] like Fig. 9 As shown, the phase modulation amplifier circuit provided in the above embodiment can be used in conjunction with a high-frequency MEMS resonator to form a high-frequency reference source. The resonator is used to generate a frequency signal I in ; Phase modulation amplifier circuit, used for frequency signal I in After amplification, the output V out and V test , V test It is used for signal testing of measuring equipment and can be used as a frequency synthesizer or mixer such as RF / microwave to provide high-precision and stable frequency reference. It can also be used as a clock source for digital systems to provide stable and accurate clock signals.

[0086] Based on the above embodiment, the output mode of the reference frequency source includes single-ended output or differential output.

[0087] Although the present invention has been shown and described with reference to specific exemplary embodiments of the present invention, it should be understood by those skilled in the art that various changes in form and detail may be made to the present invention without departing from the spirit and scope of the present invention as defined by the appended claims and their equivalents, for example: (1) The RGC structure in the transimpedance amplifier can be replaced by a common source and common gate structure to adapt to different gain and bandwidth requirements while maintaining the stability and low noise characteristics of the circuit. (2) The current multiplexing structure of the Cherry-Hooper amplifier can be replaced by a traditional common source amplifier structure to simplify the overall design and improve the stability of the circuit. This is especially true in applications that are not sensitive to environmental changes. (3) The source follower of the transimpedance amplifier can be replaced by a common source circuit structure, which can provide good isolation while increasing some additional voltage gain. (4) The single-ended design of the mixer in the circuit can be changed to a fully differential form to improve the circuit's ability to resist common mode interference and signal processing speed, which is suitable for high-speed or high-precision application scenarios. (5) The implementation of a dual-gate structure mixer can convert passive resistors into equivalent resistors of active device transistors. MOS tubes are replaced by triodes. (6) Certain components in the circuit may be manufactured using different materials or processes to optimize performance, cost, or reliability, such as using silicon-based semiconductors, gallium arsenide (GaAs), or other compound semiconductor materials. Through these changes and substitutions, the circuit design of the present disclosure can be more flexibly adapted to different application requirements and technical conditions while maintaining its core advantages and performance characteristics.

[0088] It should be noted that the ordinal numbers used in the specification and claims, such as "first", "second", "third", etc., to modify the corresponding elements, do not mean that the element has any ordinal number, nor do they represent the order of one element and another element, or the order of the manufacturing method. The use of these ordinal numbers is only used to make a component with a certain name clearly distinguishable from another component with the same name. Furthermore, the word "comprises" or "includes" does not exclude the existence of elements or steps not listed in the claims. The word "a" or "an" placed before an element does not exclude the existence of multiple such elements.

[0089] The present invention can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. The various component embodiments of the present invention can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) can be used in practice to implement some or all functions of some or all components in the relevant equipment according to an embodiment of the present invention. The present invention can also be implemented as a device or apparatus program (e.g., a computer program and a computer program product) for executing part or all of the methods described herein. Such a program implementing the present invention can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0090] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0091] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A phase modulation amplifier circuit, characterized in that: include: A phase shifter, comprising a first input terminal and a first output terminal, wherein the first input terminal is used to input a first voltage, and the first output terminal is used to output a second voltage, wherein the second voltage is a voltage after the first voltage is phase-shifted; wherein the first voltage is a voltage generated after the initial signal is amplified; A processing circuit, comprising a first transistor and a second transistor, wherein a source of the first transistor is connected to a drain of the second transistor, a gate of the first transistor receives a second voltage, and a gate of the second transistor receives a third voltage; based on a nonlinear effect of the first transistor and the second transistor, determining a mixed signal of the second voltage and the third voltage, wherein the mixed signal comprises a combined frequency signal and a difference frequency signal; The third voltage is a voltage generated after the input signal is amplified, and the phase of the third voltage is synchronized with the phase of the initial signal.

2. The phase modulation amplifier circuit according to claim 1, characterized in that: The processing circuit further includes: a filter, an input end of which is connected to the first input end and the drain of the second transistor, and the filter is used to output the difference frequency signal.

3. The phase modulation amplifier circuit according to claim 2, characterized in that: The phase shifter comprises: a capacitor, one end of which is input with the first voltage; a third transistor, a drain of which is connected to the other end of the capacitor and the gate of the first transistor, and a gate of which is connected to the output end of the filter; Wherein, based on the difference frequency signal, the on-resistance value of the third transistor is adjusted to synchronize the phases of the second voltage and the third voltage.

4. The phase modulation amplifier circuit according to claim 1, characterized in that: Also includes: A first branch, used for amplifying the initial signal to generate the first voltage; The second branch is used to amplify the initial signal to generate the third voltage.

5. The phase modulation amplifier circuit according to claim 4, characterized in that: The initial signal is a current signal, and the first branch includes: A first amplifier, used to amplify the current signal to generate the first voltage; An isolation circuit is connected to the first amplifier and the phase shifter and is used to isolate the parasitic capacitance of the phase shifter.

6. The phase modulation amplifier circuit according to claim 5, characterized in that: The first amplifier includes a circuit structure with gate voltage feedback, and the circuit structure with gate voltage feedback is used to reduce the resistance value of the input current signal.

7. The phase modulation amplifier circuit according to claim 5, characterized in that: The isolation circuit comprises: a fourth transistor, a gate of which is connected to the output terminal of the first amplifier; The first resistor has one end connected to the source of the fourth transistor and the other end connected to the ground.

8. The phase modulation amplifier circuit according to claim 5, characterized in that: The second branch comprises: A second amplifier, used for generating a fourth voltage after performing a first-stage amplification on the current signal; The third amplifier is used to generate the third voltage after performing a second-stage amplification on the fourth voltage.

9. A reference frequency source, characterized in that: include: A resonator for generating a frequency signal; The phase modulation amplifier circuit described in any one of claims 1 to 8 is used to amplify the frequency signal and then output it.

10. The reference frequency source according to claim 9, characterized in that: Output modes include single-ended output or differential output.

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