Colpitts oscillator circuit, phase-locked loop circuit and electronic equipment

Abstract

The present invention discloses a Colpitts oscillator circuit, a phase-locked loop circuit and an electronic device, wherein the Colpitts oscillator circuit comprises: a first transistor and a second transistor; a first capacitor connected between the first end and the second end of the first transistor; a second capacitor connected between the first end and the second end of the second transistor; a third capacitor and a fourth capacitor connected in series between the second end of the first transistor and the second end of the second transistor in sequence; a current source providing a bias current; a first magnetic coupling element, wherein the first end of the first magnetic coupling element is connected to the first end of the first transistor, the second end of the first magnetic coupling element is connected to the first end of the second transistor, and the third end and the fourth end of the first magnetic coupling element provide a first differential output signal of the Colpitts oscillator circuit. The present invention can realize multi-channel differential output signals with low power consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of crystal oscillators, and in particular to a Colpitts oscillator circuit, a phase-locked loop circuit and electronic equipment. Background Art

[0002] The voltage-controlled oscillator (VCO) is the module with the highest operating frequency in the frequency source system. It is a nonlinear circuit that converts direct current (DC) energy into alternating current (AC) waveform. VCO is the core module of the frequency source. It determines some key performances of the frequency source. A reasonable VCO design is a prerequisite for achieving good performance of the frequency source system. The voltage-controlled oscillator is one of the main circuits that constitute the phase-locked loop (PLL). The phase-locked loop circuit composed of the voltage-controlled oscillator provides a carrier signal in the transmitter and provides a local oscillator signal in the receiver for mixing with the RF signal. In wireless communications, especially in the field of professional wireless communications, the voltage-controlled oscillator is required to have a wide frequency range while ensuring phase noise performance.

[0003] The Colpitts oscillator is a capacitor three-point LC oscillator circuit, which is an oscillator circuit structure first proposed by American engineer Colpitts. The Colpitts oscillator has excellent phase noise performance and is widely used in various circuits such as frequency sources, phase-locked loops, and frequency synthesizers. Traditional single-ended Colpitts oscillators are susceptible to interference from various factors in integrated circuits, especially in radio frequency integrated circuits. Therefore, differential Colpitts oscillators with relatively excellent anti-interference performance are often used in existing designs.

[0004] In actual application scenarios, a Colpitts oscillator often needs to drive multiple subsequent circuit modules, such as in a wireless transceiver. Figure 1 As shown, the Colpitts oscillator circuit 30 needs to drive the receiving mixer 40 and the frequency divider 50. However, the resonant circuit of the traditional differential Colpitts oscillator can only provide one output drive. At the same time, the existing Colpitts oscillator requires multiple independent driving amplifiers at the output driving stage to drive these subsequent circuit modules, which will undoubtedly increase the overall power consumption of the system.

[0005] Therefore, it is necessary to provide an improved technical solution to overcome the above technical problems existing in the prior art. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a Colpitts oscillator circuit, a phase-locked loop circuit and an electronic device, which can realize multi-channel differential output signals with low power consumption.

[0007] According to a first aspect of the present disclosure, there is provided a Colpitts oscillator circuit, comprising: a first transistor and a second transistor;

[0008] A first capacitor connected between the first terminal and the second terminal of the first transistor;

[0009] A second capacitor connected between the first terminal and the second terminal of the second transistor;

[0010] a third capacitor and a fourth capacitor, wherein the third capacitor and the fourth capacitor are sequentially connected in series between the second end of the first transistor and the second end of the second transistor;

[0011] A current source, used for providing a bias current for the Colpitts oscillator circuit;

[0012] A first magnetic coupling element, wherein a first end of the first magnetic coupling element is connected to a first end of the first transistor, a second end of the first magnetic coupling element is connected to a first end of the second transistor, and a third end and a fourth end of the first magnetic coupling element provide a first differential output signal of the Colpitts oscillator circuit.

[0013] Optionally, the first magnetic coupling element includes any one of a transformer and a coupled microstrip line.

[0014] Optionally, the first transistor and the second transistor are both field effect transistors, the first terminals of the first transistor and the second transistor are both gates, the second terminals of the first transistor and the second transistor are both sources, and the third terminals of the first transistor and the second transistor are both drains; or

[0015] The first transistor and the second transistor are both bipolar transistors and heterojunction bipolar transistors, the first ends of the first transistor and the second transistor are bases, the second ends of the first transistor and the second transistor are emitters, and the third ends of the first transistor and the second transistor are collectors.

[0016] Optionally, it also includes:

[0017] a third transistor, a second terminal of the third transistor being connected to a third terminal of the first transistor;

[0018] a fourth transistor, wherein a second terminal of the fourth transistor is connected to a third terminal of the second transistor, and a first terminal of the fourth transistor is connected to a first terminal of the third transistor;

[0019] a second magnetic coupling element, wherein a first end of the second magnetic coupling element is connected to the third end of the third transistor, a second end of the second magnetic coupling element is connected to the third end of the fourth transistor, the second magnetic coupling element receives a supply voltage between the first end and the second end, and provides a second differential output signal of the Colpitts oscillator circuit at the third end and the fourth end.

[0020] Optionally, the second magnetic coupling element includes any one of a transformer and a coupled microstrip line.

[0021] Optionally, the third transistor and the fourth transistor are both field effect transistors, the first terminals of the third transistor and the fourth transistor are both gates, the second terminals of the third transistor and the fourth transistor are both sources, and the third terminals of the third transistor and the fourth transistor are both drains; or

[0022] The third transistor and the fourth transistor are both bipolar transistors and heterojunction bipolar transistors, the first ends of the third transistor and the fourth transistor are bases, the second ends of the third transistor and the fourth transistor are emitters, and the third ends of the third transistor and the fourth transistor are collectors.

[0023] Optionally, it also includes:

[0024] a third magnetic coupling element, wherein the first end of the third magnetic coupling element is connected to the second end of the first transistor, the second end of the third magnetic coupling element is connected to the second end of the second transistor, and the third end and the fourth end of the third magnetic coupling element provide a third differential output signal of the Colpitts oscillator circuit.

[0025] Optionally, the third magnetic coupling element includes any one of a transformer and a coupled microstrip line.

[0026] According to a second aspect of the present disclosure, a phase-locked loop circuit is provided, comprising: the Colpitts oscillator circuit as described above, providing at least one differential output signal;

[0027] A frequency divider, for dividing the frequency of the first differential output signal output by the Colpitts oscillator circuit and outputting the signal;

[0028] A frequency and phase detector, receiving the first differential output signal after frequency division and performing phase comparison, and outputting a compared phase difference signal;

[0029] A filter, filtering the compared phase difference signal and outputting the resultant signal to the Colpitts oscillator circuit;

[0030] The mixer receives the second differential output signal output by the Colpitts oscillator circuit.

[0031] According to a third aspect of the present disclosure, an electronic device is provided, comprising: the Colpitts oscillator circuit as described above, providing at least one differential output signal.

[0032] The beneficial effects of the present invention include at least:

[0033] The Colpitts oscillator circuit of the embodiment of the present invention transmits the energy of the transistor to the secondary part of the first magnetic coupling element by means of magnetic coupling, thereby realizing the passive output of the differential signal, so that there is no need to set up an independent driving amplifier at the output driving stage of the Colpitts oscillator to drive the subsequent circuit module, thereby reducing the overall power consumption of the system.

[0034] In a preferred embodiment, the Colpitts oscillator further includes a differential load unit having a second magnetic coupling element, and based on the magnetic coupling output of the second magnetic coupling element, a low-power two-way differential signal output of the Colpitts oscillator is achieved.

[0035] In a preferred embodiment, a third magnetic coupling element is provided as a differential feedback unit of the Colpitts oscillator, and based on the magnetic coupling output of the third magnetic coupling element, a low-power three-way differential signal output of the Colpitts oscillator is achieved.

[0036] It should be noted that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of the structure of a phase-locked loop circuit provided according to an embodiment of the present invention is shown;

[0038] Figure 2 A schematic diagram of the structure of an existing differential Colpitts oscillator is shown;

[0039] Figure 3 A schematic diagram of the structure of an existing driving amplifier is shown;

[0040] Figure 4 A schematic diagram of the structure of a Colpitts oscillator provided according to a first embodiment of the present invention is shown;

[0041] Figure 5 A schematic diagram of the structure of a Colpitts oscillator provided according to a second embodiment of the present invention is shown;

[0042] Figure 6 A schematic structural diagram of a Colpitts oscillator provided according to a third embodiment of the present invention is shown. DETAILED DESCRIPTION

[0043] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0044] like Figure 2 As shown, the existing differential Colpitts oscillator includes a transistor Q1, a transistor Q2, an inductor L1, capacitors C1-C4 and a current source I1. Among them, the capacitor C1 is connected between the emitter and the base of the transistor Q1, the capacitor C2 is connected between the emitter and the base of the transistor Q2, the capacitors C3 and C4 are connected in series between the emitter of the transistor Q1 and the emitter of the transistor Q2, the current source I1 is connected between the emitter of the transistor Q1 and the reference ground, and the transistor Q1 and the transistor Q2 adopt a differential connection mode of a common collector, and the base of the transistor Q1 and the transistor Q2 is used as the differential output signal terminal OUT1+ / OUT1-. It can be understood that, Figure 2 The Colpitts oscillator shown can only output a differential output signal based on the resonance of the inductor L1 and the capacitor.

[0045] However, Figure 2 The differential signal output by the Colpitts oscillator shown cannot directly drive the subsequent circuit or module, and needs to be converted by a driver amplifier before it can be used for subsequent driving. Figure 3 As shown, it includes a transistor Q3 and a current source I2. The collector of the transistor Q3 receives the supply voltage, and the base of the transistor Q3 receives the Figure 2 The output signal of the output end of the Colpitts oscillator is connected to the reference ground through the current source I2 at the emitter of the transistor Q3. The drive amplifier outputs the drive signal for driving the subsequent circuit at the emitter of the transistor Q3. It can be understood that the drive amplifier is an active drive amplifier, which will increase the power consumption of the system.

[0046] Based on this, an embodiment of the present invention provides a new Colpitts oscillator circuit structure to solve the above problems existing in the prior art.

[0047] It should be noted that the Colpitts oscillator disclosed in the present invention can be applied to any electronic device that requires an oscillation circuit to provide at least one differential output signal for the electronic device.

[0048] like Figure 1 As shown, the electronic device is, for example, a wireless transceiver including a phase-locked loop circuit, and the phase-locked loop circuit includes: a phase frequency detector 10 , a filter 20 , a Colpitts oscillator circuit 30 , a frequency divider 40 and a mixer 50 .

[0049] The Colpitts oscillator circuit 30 is used to provide at least one differential output signal. The frequency divider 50 divides the first differential output signal output by the Colpitts oscillator circuit 30 and outputs it. The frequency detector 10 receives the first differential output signal after the frequency division output by the frequency divider 50, performs phase comparison and outputs the compared phase difference signal. The filter 20 filters the compared phase difference signal output by the frequency detector 10 and outputs it to the Colpitts oscillator circuit 30. The mixer 40 receives the second differential output signal output by the Colpitts oscillator circuit 30.

[0050] The circuit structure of the Colpitts oscillator circuit 30 provided in the first embodiment of the present invention is as follows: Figure 4 As shown, it can be used as the core circuit part of the Colpitts oscillator circuit 30. In this embodiment, the core circuit part of the Colpitts oscillator circuit 30 is a differential structure formed by two single-ended Colpitts oscillator circuits through a common virtual ground point, which specifically includes: a first transistor Q11, a second transistor Q12, a first capacitor C11, a second capacitor C12, a third capacitor C13, a fourth capacitor C14, a current source I11 and a first magnetic coupling element TR11. Among them, the first capacitor C11 is connected between the first end and the second end of the first transistor Q11. The second capacitor C12 is connected between the first end and the second end of the second transistor Q12. The third capacitor C13 and the fourth capacitor C14 are connected in series in sequence between the second end of the first transistor Q11 and the second end of the second transistor Q12. The current source I11 is used to provide a bias current for the Colpitts oscillator circuit 30. The first end of the first magnetic coupling element TR11 is connected to the first end of the first transistor Q11, the second end of the first magnetic coupling element TR11 is connected to the first end of the second transistor Q12, and the third end OUT1+ and the fourth end OUT1- of the first magnetic coupling element TR11 provide a first differential output signal of the Colpitts oscillator circuit 30.

[0051] Optionally, in this embodiment, the first transistor Q11 and the second transistor Q12 are any one of a field effect transistor, a bipolar transistor and a heterojunction bipolar transistor (HBT). It should be understood that when the first transistor Q11 and the second transistor Q12 are both field effect transistors (such as NMOS field effect transistors), the first ends of the first transistor Q11 and the second transistor Q12 correspond to the gate of the transistor, the second ends of the first transistor Q11 and the second transistor Q12 correspond to the source of the transistor, and the third ends of the first transistor Q11 and the second transistor Q12 correspond to the drain of the transistor. When the first transistor Q11 and the second transistor Q12 are any one of a bipolar transistor (such as an NPN bipolar transistor) and a heterojunction bipolar transistor, the first ends of the first transistor Q11 and the second transistor Q12 correspond to the base of the transistor, the second ends of the first transistor Q11 and the second transistor Q12 correspond to the emitter of the transistor, and the third ends of the first transistor Q11 and the second transistor Q12 correspond to the collector of the transistor.

[0052] Optionally, in this embodiment, the first magnetic coupling element TR11 includes any one of a transformer and a coupled microstrip line. The first end and the second end of the first magnetic coupling element TR11 are respectively the two ends of its main coil or main microstrip line, and the main coil or main microstrip line of the first magnetic coupling element TR11 is connected to the Colpitts oscillation circuit by connecting with other transistors and / or capacitors to form a circuit loop; the third end OUT1+ and the fourth end OUT1- of the first magnetic coupling element TR11 are respectively the two ends of its secondary coil or secondary microstrip line, and in this embodiment, serve as the output end of the first differential output signal of the Colpitts circuit 30.

[0053] In the embodiment of the present invention, the first magnetic coupling element TR11 is used as the LC differential resonant circuit component of the Colpitts oscillator circuit 30. When the Colpitts oscillator circuit 30 is operating normally, an oscillating voltage signal exists between the first end and the second end of the first magnetic coupling element TR11. Through magnetic coupling, the oscillating voltage signal can be outputted at the third end and the fourth end of the first magnetic coupling element TR11 in a passive manner and provided to the external circuit, thereby realizing the passive output of the differential signal. At the same time, the first differential output signal outputted at the third end OUT1+ and the fourth end OUT1- of the first magnetic coupling element TR11 can directly drive the external circuit without the need to set up an additional independent driving amplifier after the output end of the Colpitts oscillator circuit, thereby reducing the overall power consumption of the system.

[0054] Furthermore, the circuit structure of the Colpitts oscillator circuit 30 provided in the second embodiment of the present invention is as follows: Figure 5As shown, it basically adopts the same structure as the first embodiment mentioned above, and will not be repeated here. The difference between this embodiment and the first embodiment mentioned above is that the Colpitts oscillator circuit 30 in this embodiment also includes: a third transistor Q13, a fourth transistor Q14 and a second magnetic coupling element TR12. Among them, the first end of the second magnetic coupling element TR12 is connected to the third end of the third transistor Q13, the second end of the second magnetic coupling element TR12 is connected to the third end of the fourth transistor Q14, the second magnetic coupling element TR12 receives the power supply voltage VCC between the first end and the second end, and provides the second differential output signal of the Colpitts oscillator circuit 30 at its third end OUT2+ and the fourth end OUT2-. The second end of the third transistor Q12 is connected to the third end of the first transistor Q11. The second end of the fourth transistor Q14 is connected to the third end of the second transistor Q12, and the first end of the fourth transistor Q14 is connected to the first end of the third transistor Q13.

[0055] Optionally, in this embodiment, the third transistor Q13 and the fourth transistor Q14 are any of a field effect transistor, a bipolar transistor and a heterojunction bipolar transistor. And it should be understood that when the third transistor Q13 and the fourth transistor Q14 are both field effect transistors (such as NMOS field effect transistors), the first ends of the third transistor Q13 and the fourth transistor Q14 correspond to the gate of the transistor, the second ends of the third transistor Q13 and the fourth transistor Q14 correspond to the source of the transistor, and the third ends of the third transistor Q13 and the fourth transistor Q14 correspond to the drain of the transistor. When the third transistor Q13 and the fourth transistor Q14 are any of a bipolar transistor (such as an NPN bipolar transistor) and a heterojunction bipolar transistor, the first ends of the third transistor Q13 and the fourth transistor Q14 correspond to the base of the transistor, the second ends of the third transistor Q13 and the fourth transistor Q14 correspond to the emitter of the transistor, and the third ends of the third transistor Q13 and the fourth transistor Q14 correspond to the collector of the transistor.

[0056] Optionally, in this embodiment, the second magnetic coupling element TR12 includes any one of a transformer and a coupled microstrip line. The first end and the second end of the second magnetic coupling element TR12 are respectively the two ends of its main coil or main microstrip line, and the main coil or main microstrip line of the second magnetic coupling element TR12 is connected to the Colpitts oscillation circuit by connecting with other elements in the circuit, such as the third transistor Q13 and the fourth transistor Q14, to form a circuit loop; the third end OUT2+ and the fourth end OUT2- of the second magnetic coupling element TR12 are respectively the two ends of its secondary coil or secondary microstrip line, and in this embodiment, serve as the output end of the second differential output signal of the Colpitts circuit 30.

[0057] In the embodiment of the present invention, the second magnetic coupling element TR12 is used as the differential load unit of the Colpitts oscillator circuit 30, and the common base amplifier composed of the third transistor Q13 and the fourth transistor Q14 is used to realize mutual isolation from the core circuit part in the Colpitts oscillator circuit 30. When the Colpitts oscillator circuit 30 is working normally, there is an oscillating voltage signal between the first end and the second end of the second magnetic coupling element TR12. Through magnetic coupling, the oscillating voltage signal can be output in a passive manner at the third end OUT2+ and the fourth end OUT2- of the second magnetic coupling element TR12, and provided to the external circuit, thereby realizing the passive output of the differential signal. At the same time, the second differential output signal outputted from the third end OUT2+ and the fourth end OUT2- of the second magnetic coupling element TR12 can directly realize the driving of the external circuit without the need to set up an additional independent driving amplifier after the output end of the Colpitts oscillator circuit, thereby reducing the overall power consumption of the system. It can be understood that based on the Colpitts oscillator circuit structure provided in this embodiment, two-way differential signal output can be realized at the same time with low loss, and the application scenario is wider.

[0058] Furthermore, the circuit structure of the Colpitts oscillator circuit 30 provided in the third embodiment of the present invention is as follows: Figure 6 As shown, it basically adopts the same structure as the first embodiment or the second embodiment mentioned above, and will not be repeated here. The difference between this embodiment and the first embodiment or the second embodiment mentioned above is that the Colpitts oscillator circuit 30 in this embodiment also includes: a third magnetic coupling element TR13. Among them, the first end of the third magnetic coupling element TR13 is connected to the second end of the first transistor Q11, the second end of the third magnetic coupling element TR13 is connected to the second end of the second transistor Q12, and the third end OUT3+ and the fourth end OUT3- of the third magnetic coupling element TR13 provide the third differential output signal of the Colpitts oscillator circuit 30.

[0059] Optionally, in this embodiment, the third magnetic coupling element TR13 includes any one of a transformer and a coupled microstrip line. The first end and the second end of the third magnetic coupling element TR13 are respectively the two ends of its main coil or main microstrip line, and the main coil or main microstrip line of the third magnetic coupling element TR13 is connected to the Colpitts oscillation circuit by connecting with other elements in the circuit, such as the first transistor Q11 and the second transistor Q12, to form a circuit loop; the third end OUT3+ and the fourth end OUT3- of the third magnetic coupling element TR13 are respectively the two ends of its secondary coil or secondary microstrip line, and in this embodiment, serve as the output end of the third differential output signal of the Colpitts circuit 30.

[0060] In the embodiment of the present invention, the third magnetic coupling element TR13 is used as the differential feedback unit of the Colpitts oscillator circuit 30. When the Colpitts oscillator circuit 30 is working normally, there is an oscillating voltage signal between the first end and the second end of the third magnetic coupling element TR13. Through magnetic coupling, the oscillating voltage signal can be output at the third end OUT3+ and the fourth end OUT3- of the third magnetic coupling element TR13 in a passive manner, and provided to the external circuit, thereby realizing the passive output of the differential signal. At the same time, the third differential output signal outputted at the third end OUT3+ and the fourth end OUT3- of the third magnetic coupling element TR13 can directly drive the external circuit without the need to set up an additional independent driving amplifier after the output end of the Colpitts oscillator circuit, thereby reducing the overall power consumption of the system. It can be understood that based on the Colpitts oscillator circuit structure provided in this embodiment, two or even three differential signal outputs can be realized simultaneously with low loss, and the application scenarios are wider.

[0061] In summary, the Colpitts oscillator circuit of the embodiment of the present invention transfers the energy of the transistor to the secondary part of the first magnetic coupling element by means of magnetic coupling, thereby realizing the passive output of the differential signal, so that there is no need to set up an independent driving amplifier at the output driving stage of the Colpitts oscillator to drive the subsequent circuit module, thereby reducing the overall power consumption of the system.

[0062] In a preferred embodiment, the Colpitts oscillator further includes a differential load unit having a second magnetic coupling element, and based on the magnetic coupling output of the second magnetic coupling element, a low-power two-way differential signal output of the Colpitts oscillator is achieved.

[0063] In a preferred embodiment, a third magnetic coupling element is provided as a differential feedback unit of the Colpitts oscillator, and based on the magnetic coupling output of the third magnetic coupling element, a low-power three-way differential signal output of the Colpitts oscillator is achieved.

[0064] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present invention.

Claims

1. A Colpitts oscillator circuit, wherein: include: a first transistor and a second transistor; A first capacitor connected between the first terminal and the second terminal of the first transistor; A second capacitor connected between the first terminal and the second terminal of the second transistor; a third capacitor and a fourth capacitor, wherein the third capacitor and the fourth capacitor are sequentially connected in series between the second end of the first transistor and the second end of the second transistor; A current source, used for providing a bias current for the Colpitts oscillator circuit; a first magnetic coupling element, wherein a first end of the first magnetic coupling element is connected to a first end of the first transistor, a second end of the first magnetic coupling element is connected to a first end of the second transistor, and a third end and a fourth end of the first magnetic coupling element provide a first differential output signal of the Colpitts oscillator circuit; a third transistor, a second terminal of the third transistor being connected to a third terminal of the first transistor; a fourth transistor, wherein a second terminal of the fourth transistor is connected to a third terminal of the second transistor, and a first terminal of the fourth transistor is connected to a first terminal of the third transistor; a second magnetic coupling element, wherein a first end of the second magnetic coupling element is connected to a third end of the third transistor, a second end of the second magnetic coupling element is connected to a third end of the fourth transistor, the second magnetic coupling element receives a supply voltage between the first end and the second end, and provides a second differential output signal of the Colpitts oscillator circuit at the third end and the fourth end; The first transistor, the second transistor, the third transistor and the fourth transistor are all field effect transistors, the first terminals of the first transistor, the second transistor, the third transistor and the fourth transistor are all gates, the second terminals of the first transistor, the second transistor, the third transistor and the fourth transistor are all sources, and the third terminals of the first transistor, the second transistor, the third transistor and the fourth transistor are all drains; or The first transistor, the second transistor, the third transistor and the fourth transistor are any of bipolar transistors and heterojunction bipolar transistors, the first ends of the first transistor, the second transistor, the third transistor and the fourth transistor are bases, the second ends of the first transistor, the second transistor, the third transistor and the fourth transistor are emitters, and the third ends of the first transistor, the second transistor, the third transistor and the fourth transistor are collectors.

2. The Colpitts oscillator circuit according to claim 1, wherein: The first magnetic coupling element includes any one of a transformer and a coupled microstrip line.

3. The Colpitts oscillator circuit according to claim 1, wherein: The second magnetic coupling element includes any one of a transformer and a coupled microstrip line.

4. The Colpitts oscillator circuit according to any one of claims 1 to 3, wherein: Also includes: a third magnetic coupling element, wherein the first end of the third magnetic coupling element is connected to the second end of the first transistor, the second end of the third magnetic coupling element is connected to the second end of the second transistor, and the third end and the fourth end of the third magnetic coupling element provide a third differential output signal of the Colpitts oscillator circuit.

5. The Colpitts oscillator circuit according to claim 4, wherein: The third magnetic coupling element includes any one of a transformer and a coupled microstrip line.

6. A phase-locked loop circuit, wherein: include: The Colpitts oscillator circuit according to any one of claims 1 to 5, providing at least one differential output signal; A frequency divider, for dividing the frequency of the first differential output signal output by the Colpitts oscillator circuit and outputting the signal; A frequency and phase detector, receiving the first differential output signal after frequency division and performing phase comparison, and outputting a compared phase difference signal; A filter, filtering the compared phase difference signal and outputting the resultant signal to the Colpitts oscillator circuit; The mixer receives the second differential output signal output by the Colpitts oscillator circuit.

7. An electronic device, wherein: include: The Colpitts oscillator circuit according to any one of claims 1 to 5, providing at least one differential output signal.

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