Noise circulation voltage-controlled oscillator based on switch coupling inductor
By introducing a switch-coupled inductor module and a noise cycle module into the voltage-controlled oscillator, the problem of designing a wide-band low-phase noise voltage-controlled oscillator in the prior art is solved, and the frequency operating range is expanded and cost control is achieved.
Patent Information
- Application Number
- CN202411557428.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-04
- Publication Date
- 2025-03-11
AI Technical Summary
The prior art is difficult to take into account both wideband coverage and low phase noise when designing wideband low-phase noise voltage-controlled oscillators, and traditional methods have great challenges in area and power consumption.
A noise cycle voltage-controlled oscillator based on switch-coupled inductor is adopted to control the effective inductor value through the switch-coupled inductor module, and combine it with the tuning gain module, switching capacitor array and noise cycle module to expand the frequency working range without increasing the circuit area.
Without increasing the circuit area, the frequency operating range of the voltage-controlled oscillator is expanded, the cost is reduced, and phase noise is controlled, meeting the demand for wide-band low phase noise.
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Figure CN119602707A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of integrated circuits, and in particular to a noise cycle voltage-controlled oscillator based on a switch-coupled inductor. Background Art
[0002] With the continuous development of 5G communication technology, the demand for signal sources with wide-band working range and low phase noise is increasing. The voltage-controlled oscillator is the core module of the phase-locked loop, which determines whether the phase-locked loop can up-convert the signal that meets the transmission quality requirements as the local oscillator in the wireless transceiver system. In order to cope with various 5G communication protocols, it is often necessary to design a broadband voltage-controlled oscillator, which has a significant compromise with low phase noise. At the same time, as the process becomes more advanced, the Q value of various passive components such as capacitors continues to decrease, which also causes certain difficulties in designing a voltage-controlled oscillator that meets the requirements. Therefore, the design of a broadband and low-phase-noise voltage-controlled oscillator must ensure maximum loop stability when applied to a phase-locked loop.
[0003] Traditional broadband low phase noise voltage-controlled oscillators mainly use a large number of switched capacitor arrays to cover the broadband when covering the broadband, but this approach will introduce large parasitic capacitance when designing the voltage-controlled oscillator, which is not conducive to achieving broadband. Another approach is to use multiple resonant cavities to cover the broadband, but this is costly in terms of area and power consumption. Summary of the invention
[0004] The present application provides a noise cycle voltage-controlled oscillator based on a switch-coupled inductor, which can increase the frequency operating range of the voltage-controlled oscillator without increasing the circuit area, thereby controlling the cost.
[0005] The embodiment of the present application provides a noise circulation voltage-controlled oscillator based on a switched coupled inductor, comprising a switched coupled inductor module, a tuning gain module, a switched capacitor array and a noise circulation module connected in sequence;
[0006] The switch coupled inductor module includes a primary coil, a secondary coil, a switch tube, a first resistor, a second resistor, a first inverter and a second inverter; the drain and source of the switch tube are respectively connected to the two ends of the secondary coil;
[0007] The input end of the first inverter receives the first control voltage, and the output end is respectively connected to the input end of the second inverter, the positive electrode of the first resistor and the positive electrode of the second resistor; the output end of the second inverter is connected to the gate of the switch tube; the negative electrode of the first resistor is connected to the drain of the switch tube, and the negative electrode of the second resistor is connected to the source of the switch tube;
[0008] The primary coil and the secondary coil are arranged correspondingly and are respectively connected to a tuning gain module and a power supply.
[0009] Furthermore, the primary coil is octagonal, and the secondary coil is rhombus-shaped.
[0010] Further, the tuning gain module includes a first capacitor tube, a second capacitor tube, a first PMOS tube and a second PMOS tube;
[0011] The positive electrodes of the first capacitor tube and the second capacitor tube are connected to two ends of the primary coil respectively;
[0012] The cathodes of the first capacitor tube and the second capacitor tube are connected to each other and are respectively connected to the substrate ends of the first PMOS tube and the second PMOS tube; the substrate ends are used to receive the tuning voltage;
[0013] Sources and drains of the first PMOS tube and the second PMOS tube are both grounded.
[0014] Furthermore, the switched capacitor array includes a plurality of identical array units; the capacitance values in each array unit are different from each other.
[0015] Further, the array unit includes a third inverter, a fourth inverter, a third resistor, a fourth resistor, a first NMOS tube, a first capacitor and a second capacitor; the input end of the third inverter receives the second control voltage;
[0016] The output end of the third inverter is connected to the input end of the fourth inverter, the positive electrode of the third resistor and the positive electrode of the fourth resistor respectively; the output end of the fourth inverter is connected to the gate of the first NMOS tube;
[0017] The source of the first NMOS tube is connected to the negative electrode of the third resistor and the negative electrode of the first capacitor respectively, and the drain of the first NMOS tube is connected to the negative electrode of the fourth resistor and the negative electrode of the second capacitor respectively.
[0018] Furthermore, when the second control voltage received by the third inverter is at a high level, the array unit corresponding to the third inverter joins in the operation of the switch capacitor array, otherwise it does not join in the operation.
[0019] Furthermore, the number of array units in the switched capacitor array is four.
[0020] Further, the noise circulation module includes a second NMOS tube, a third NMOS tube, a third PMOS tube, a fourth PMOS tube, a third capacitor, a fourth capacitor, a fifth resistor and a sixth resistor;
[0021] The gate of the second NMOS tube is connected to the positive electrode of the third capacitor and the drain of the third NMOS tube respectively;
[0022] The gate of the third NMOS tube is connected to the positive electrode of the fourth capacitor and the drain of the second NMOS tube respectively;
[0023] The source of the second NMOS tube is connected to the source of the third PMOS tube; the source of the third NMOS tube is connected to the source of the fourth PMOS tube; the gate of the third PMOS tube is connected to the negative electrode of the fourth capacitor and the fifth resistor respectively; the gate of the fourth PMOS tube is connected to the negative electrode of the third capacitor and the sixth resistor respectively; the fifth resistor and the sixth resistor are connected to each other and receive a bias voltage;
[0024] The drains of the third PMOS tube and the fourth PMOS tube are grounded.
[0025] Furthermore, the transconductance of the second NMOS tube and the third NMOS tube is equal to the transconductance of the third PMOS tube and the fourth PMOS tube.
[0026] Furthermore, the coupling coefficient between the primary coil and the secondary coil is 0.2.
[0027] In summary, compared with the prior art, the technical solution provided in the embodiment of the present application has at least the following beneficial effects:
[0028] A noise circulating voltage-controlled oscillator based on a switch-coupled inductor provided in an embodiment of the present application introduces a switch-coupled inductor module, and controls the closing and closing of the switch tube by a first control voltage, thereby controlling the effective inductance value connected to the resonant cavity, ensuring that the wideband coverage is not affected by the introduction of too many bits of switch capacitors in the voltage-controlled oscillator, thereby increasing the frequency operating range; secondly, the introduced switch-coupled inductor module has less significant overhead in terms of layout area than a single inductor, thereby controlling costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 A circuit diagram of a noise cycle voltage-controlled oscillator based on a switch-coupled inductor is provided in accordance with an embodiment of the present application.
[0030] Figure 2 A schematic diagram of the layout of the primary coil and the secondary coil in a switch coupled inductor module provided in one embodiment of the present application.
[0031] Figure 3 A diagram showing simulation results of a tuning gain module under different capacitances provided in one embodiment of the present application.
[0032] Figure 4 A circuit analysis diagram of a half-side small signal of a noise circulation module provided in one embodiment of the present application.
[0033] Figure 5 A schematic diagram of P1 tube noise analysis provided in one embodiment of the present application.
[0034] Figure 6 A schematic diagram of the frequency coverage of a voltage-controlled oscillator provided in accordance with an embodiment of the present application.
[0035] Figure 7 A graph of phase noise simulation results of the present application and a traditional circuit provided for one embodiment of the present application. DETAILED DESCRIPTION
[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.
[0037] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.
[0038] See also Figure 1 The embodiment of the present application provides a noise circulation voltage-controlled oscillator based on a switch-coupled inductor, including a switch-coupled inductor module, a tuning gain module, a switch capacitor array and a noise circulation module connected in sequence; the switch-coupled inductor module includes a primary coil L1, a secondary coil L2, a switch tube M8, a first resistor R5, a second resistor R6, a first inverter INV3 and a second inverter INV4; the drain and source of the switch tube M8 are respectively connected to the two ends of the secondary coil L2.
[0039] The input end of the first inverter INV3 receives the first control voltage VSW, and the output end is respectively connected to the input end of the second inverter INV4, the positive electrode of the first resistor R5 and the positive electrode of the second resistor R6; the output end of the second inverter INV4 is connected to the gate of the switch tube M8; the negative electrode of the first resistor R5 is connected to the drain of the switch tube M8, and the negative electrode of the second resistor R6 is connected to the source of the switch tube M8; the primary coil L1 and the secondary coil L2 are correspondingly arranged, and are respectively connected to the tuning gain module and the power supply VDD.
[0040] Among them, see Figure 2 The primary coil L1 is an octagon; the secondary coil L2 is a rhombus; L1 and L2 are arranged in opposite directions, the center tap of L1 is connected to the power supply VDD, and the other two ends are connected to the output terminals VOP and VON of the voltage-controlled oscillator respectively, and the switch tube M8 is placed near the secondary coil L2. The first resistor R5, the second resistor R6, the first inverter INV3 and the second inverter INV4 are used to provide a bias voltage for the switch tube M8.
[0041] In actual operation, when the first control voltage VSW is at a high level, the high level of the gate terminal of the M8 tube is enabled, and the M8 tube is turned on. At this time, L2 is connected to the resonant cavity where only L1 originally participated in the resonance, affecting the effective inductance value. The voltage equations for L1 and L2 are as follows:
[0042] V1=jL1ωI1+jMωI2
[0043] V2=jL2ωI2+jMωI1
[0044] Specifically, when L2 is not connected, the effective inductance of the switch coupled inductor module is:
[0045]
[0046] When L2 is connected to L1, the effective inductance is:
[0047]
[0048] Wherein, k is the coupling coefficient between L1 and L2, which can be specifically taken as 0.2.
[0049] Z 11 It is the content of the radio frequency communication circuit. In the radio frequency communication circuit, the two-port network is modeled, the input port is modeled as port 1, and the output port is modeled as port 2. Then Z 11 Represents the self-impedance value of input port 1. Mathematically, impedance may be a complex value. m It means taking the imaginary part of the complex number.
[0050] In the specific implementation process, since the switch inductor structure of the present application is composed of only two single-turn inductors, it has little effect on the capacitor Q value. At the same time, by reasonably setting the size of the switch tube, oscillation can be achieved and a low phase noise level can be maintained.
[0051] The above embodiment provides a noise cycle voltage-controlled oscillator based on a switch-coupled inductor, which introduces a switch-coupled inductor module. The switching tube is controlled to be closed and closed by a first control voltage, thereby controlling the effective inductance value connected to the resonant cavity, ensuring that the wideband coverage is not affected by the introduction of too many bits of switch capacitors in the voltage-controlled oscillator, thereby increasing the frequency operating range; secondly, the introduced switch-coupled inductor module does not significantly increase the layout area compared to the single inductor overhead, thereby controlling the cost.
[0052] In some embodiments, the tuning gain module includes a first capacitor tube VAR1, a second capacitor tube VAR2, a first PMOS tube M6 and a second PMOS tube M7, wherein VAR1 and VAR2 are both variable capacitor tubes.
[0053] The positive electrodes of the first capacitor tube VAR1 and the second capacitor tube VAR2 are connected to the two ends of the primary coil L1 respectively; that is, the positive electrodes of VAR1 and VAR2 are connected to the output terminals VOP and VON of the voltage-controlled oscillator respectively.
[0054] The cathodes of the first capacitor VAR1 and the second capacitor VAR2 are connected to each other and are respectively connected to the substrate ends of the first PMOS transistor M6 and the second PMOS transistor M7; the substrate ends are used to receive the tuning voltage VTUNE.
[0055] The gate of M6 is connected to the output VOP, and the gate of M7 is connected to the output VON. After M6, M7 are connected in parallel with VAR1 and VAR2, the capacitance change is more linear. Figure 3 shown.
[0056] The source and drain of the first PMOS transistor M6 and the second PMOS transistor M7 are both grounded.
[0057] In some embodiments, the switched capacitor array includes a plurality of identical array units; the capacitance values in each array unit are different from each other. The number of array units in the switched capacitor array may specifically be four.
[0058] In some embodiments, the array unit includes a third inverter INV1, a fourth inverter INV2, a third resistor R3, a fourth resistor R4, a first NMOS transistor M5, a first capacitor C3 and a second capacitor C4.
[0059] An input terminal of the third inverter INV1 receives the second control voltage VBIT.
[0060] The output end of the third inverter INV1 is connected to the input end of the fourth inverter INV2, the positive electrode of the third resistor R3 and the positive electrode of the fourth resistor R4 respectively; the output end of the fourth inverter INV2 is connected to the gate of the first NMOS tube M5.
[0061] The source of the first NMOS transistor M5 is connected to the cathode of the third resistor R3 and the cathode of the first capacitor C3 respectively, and the drain of the first NMOS transistor M5 is connected to the cathode of the fourth resistor R4 and the cathode of the second capacitor C4 respectively.
[0062] When the second control voltage VBIT received by the third inverter INV1 is at a high level, the array unit corresponding to the third inverter INV1 is added to the operation of the switch capacitor array, that is, in the resonant cavity; otherwise, it is not added.
[0063] The above embodiment can achieve a more linear capacitance change of the switched capacitor array within the tuning voltage range by using the technology of connecting the NMOS varactor diode and the PMOS varactor diode in parallel.
[0064] In some embodiments, the noise circulation module includes a second NMOS transistor M1, a third NMOS transistor M2, a third PMOS transistor M3, a fourth PMOS transistor M4, a third capacitor C1, a fourth capacitor C2, a fifth resistor R1 and a sixth resistor R2.
[0065] The gate M1 of the second NMOS transistor is connected to the positive electrode of the third capacitor C1 and the drain of the third NMOS transistor M2 respectively.
[0066] Among them, the drain of M1 is connected to VOP, and the drain of M2 is connected to VON.
[0067] The gate of the third NMOS transistor M2 is connected to the positive electrode of the fourth capacitor C2 and the drain of the second NMOS transistor M1 respectively.
[0068] The source of the second NMOS tube M1 is connected to the source of the third PMOS tube M3; the source of the third NMOS tube M2 is connected to the source of the fourth PMOS tube M4; the gate of the third PMOS tube M3 is respectively connected to the negative electrode of the fourth capacitor C2 and the fifth resistor R1; the gate of the fourth PMOS tube M4 is respectively connected to the negative electrode of the third capacitor C1 and the sixth resistor R2.
[0069] The fifth resistor R1 and the sixth resistor R2 are connected to each other and receive the bias voltage VB.
[0070] The drains of the third PMOS tube M3 and the fourth PMOS tube M4 are grounded GND.
[0071] Specifically, when the voltage-controlled oscillator is working, the voltage swing at the differential output terminals of VOP and VON is set to V1. This change is coupled to the gates of M3 and M4 through capacitors C1 and C2 to form a swing V2. The ratio of the swing is set to:
[0072]
[0073] Among them C 1,2 is the value of C1 and C2, C g is the parasitic capacitance of the gate terminals of M3 and M4. Since the circuit is symmetrical, the small signal circuit diagram of the analysis half is as follows: Figure 4 As shown. The approximate size of the differential resistance Z is obtained as follows:
[0074]
[0075] Among them, g mn is the transconductance of NMOS tubes M1 and M2, g mp is the transconductance of PMOS tubes M3 and M4, A v The size of is n, where n is close to 1, so the approximate size of the differential negative resistance is:
[0076]
[0077] In order to make the negative resistance as large as possible, the transconductance of M1 and M2 must be kept as consistent as possible with the transconductance of M3 and M4 in the circuit.
[0078] According to the linear time-varying model of the voltage-controlled oscillator phase noise, the oscillator differential output voltage is most sensitive to noise disturbances at the zero crossing point, when the noise has the greatest impact on the phase noise. Therefore, as a simplified analysis, the power density of the noise source injected into the oscillator can be evaluated at this zero crossing moment to estimate their impact on the phase noise. To calculate and analyze the equivalent output noise current at the zero crossing moment of the differential output voltage, see Figure 5 , where P1 is Figure 1 The M3 tube in the figure is the third PMOS tube. Assuming that the swing of the differential output coupled to the gate terminals of P1 and P2 is n=1 as mentioned above, the noise current of P1 tube is analyzed as follows:
[0079]
[0080] α+β=1
[0081] Among them, it can be obtained that only part of the noise enters the resonant cavity, and the other part of the noise circulates to the P1 tube itself and flows to the ground. In order to make the above-mentioned self-noise and negative resistance as large as possible, theoretical analysis shows that the best transconductance is when the transconductance of the NMOS tube and the PMOS tube are consistent. Therefore, the consistency of transconductance should be ensured as much as possible during circuit design.
[0082] In the voltage-controlled oscillator circuit of the present application, the primary coil L1 of the switch-coupled inductor module and the switch capacitor array form a basic LC resonant cavity. The different number of switch capacitor arrays is used to roughly adjust the resonant frequency. The switch tube M8 controls whether the secondary coil L2 is connected to the LC resonant cavity, thereby changing the effective inductance value L; but since the LC resonant cavity is not ideal, there is parasitic resistance loss, that is, energy loss. The noise circulation module is used to provide equivalent negative resistance to compensate for the energy loss of the LC resonant cavity. The tuning gain linearization technology makes the change of the variable capacitor connected to the LC resonant cavity more linear when the control voltage changes, which is used to provide linear and precise frequency adjustment. Please refer to Figure 6 The switching of modes determines the effective inductance value, that is, it determines whether the overall resonant frequency range of the voltage-controlled oscillator works in LF mode or HF mode. Therefore, the voltage-controlled oscillator of the present application has flexibility in operating frequency range due to the design flexibility of the switch-coupled inductor; when it comes to a specific mode, the difference in the number of switch capacitor arrays is that in this mode, the tuning resonance is in different sub-band frequency ranges. When the carrier center frequency is 22.35GHz, the phase noise simulation results of the voltage-controlled oscillator proposed in this application are compared with the simulation results of the traditional Class-C structure voltage-controlled oscillator. Figure 7 shown.
[0083] When specifically designing the circuit of this application, it is first necessary to determine the required inductance value according to the required operating frequency and the frequency tuning range of the voltage-controlled oscillator, and according to the required tuning range. The size difference between the two different inductance values of the switch-coupled inductor module can be controlled by changing the size of the overlapping area of the secondary coil and the primary coil when customizing the inductance. In essence, it is to modify the coupling coefficient between the two coils. In addition, the size of the switch tube can be changed to fine-tune the size of the overlapping frequency range of the resonant frequency range of the two different modes. After determining the inductance value, start designing the inductance. The routing of the coil should be wide to ensure that the quality factor of the inductance is high. At the same time, the coupling coefficient should not be too small, otherwise it will be smaller after square, which will result in little difference in the inductance value between the two modes. After the inductor design is completed, the switch capacitor array is designed according to the previously determined inductance value. The design principle follows binary control tuning. The capacitance size of different units is roughly twice the difference, and the size of the switch tube is also roughly twice the relationship. However, it should be noted that the size of the switch tube should not be too large or too small. If it is too large, the parasitic capacitance will be too large, affecting the frequency tuning range. If it is too small, the turn-off resistance will be too large, affecting the phase noise performance. The size of the negative resistance tube in the noise cycle module should not be too small. A certain transconductance size must be guaranteed to ensure the start-up of the voltage-controlled oscillator. At the same time, the size of the tube that provides the working bias current must ensure that it can provide the required working current size. The coupling capacitor can be set to about ten times the parasitic capacitance of the current tube gate. The resistance value can be selected as large as possible without affecting the output phase noise size. Finally, the selection of the bias voltage should try to ensure that the transconductance of the current tube and the negative resistance tube is close to the same, so as to ensure the maximum negative resistance at the rated power consumption.
[0084] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0085] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.
Claims
1. A noise cycle voltage controlled oscillator based on a switched coupled inductor, characterized in that: It includes a switched coupled inductor module, a tuned gain module, a switched capacitor array and a noise circulation module connected in sequence; The switch coupled inductor module includes a primary coil, a secondary coil, a switch tube, a first resistor, a second resistor, a first inverter and a second inverter; the drain and source of the switch tube are respectively connected to the two ends of the secondary coil; The input end of the first inverter receives the first control voltage, and the output end is respectively connected to the input end of the second inverter, the positive electrode of the first resistor and the positive electrode of the second resistor; the output end of the second inverter is connected to the gate of the switch tube; the negative electrode of the first resistor is connected to the drain of the switch tube, and the negative electrode of the second resistor is connected to the source of the switch tube; The primary coil and the secondary coil are arranged correspondingly and are respectively connected to the tuning gain module and the power supply.
2. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 1, characterized in that: The primary coil is octagonal; the secondary coil is rhombus-shaped.
3. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 1, characterized in that: The tuning gain module includes a first capacitor tube, a second capacitor tube, a first PMOS tube and a second PMOS tube; The positive electrodes of the first capacitor tube and the second capacitor tube are connected to two ends of the primary coil respectively; The cathodes of the first capacitor tube and the second capacitor tube are connected to each other and are respectively connected to the substrate ends of the first PMOS tube and the second PMOS tube; the substrate ends are used to receive the tuning voltage; The source and drain of the first PMOS tube and the second PMOS tube are both grounded.
4. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 1, characterized in that: The switch capacitor array includes a plurality of identical array units; the capacitance values in each of the array units are different from each other.
5. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 4, characterized in that: The array unit includes a third inverter, a fourth inverter, a third resistor, a fourth resistor, a first NMOS tube, a first capacitor and a second capacitor; the input end of the third inverter receives a second control voltage; The output end of the third inverter is connected to the input end of the fourth inverter, the positive electrode of the third resistor and the positive electrode of the fourth resistor respectively; the output end of the fourth inverter is connected to the gate of the first NMOS tube; The source of the first NMOS tube is connected to the negative electrode of the third resistor and the negative electrode of the first capacitor respectively, and the drain of the first NMOS tube is connected to the negative electrode of the fourth resistor and the negative electrode of the second capacitor respectively.
6. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 5, characterized in that: When the second control voltage received by the third inverter is at a high level, the array unit corresponding to the third inverter joins in the operation of the switch capacitor array, otherwise it does not join in the operation.
7. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 6, characterized in that: The number of the array units in the switch capacitor array is 4.
8. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 1, characterized in that: The noise circulation module includes a second NMOS tube, a third NMOS tube, a third PMOS tube, a fourth PMOS tube, a third capacitor, a fourth capacitor, a fifth resistor and a sixth resistor; The gate of the second NMOS tube is connected to the positive electrode of the third capacitor and the drain of the third NMOS tube respectively; The gate of the third NMOS tube is connected to the positive electrode of the fourth capacitor and the drain of the second NMOS tube respectively; The source of the second NMOS tube is connected to the source of the third PMOS tube; the source of the third NMOS tube is connected to the source of the fourth PMOS tube; the gate of the third PMOS tube is connected to the negative electrode of the fourth capacitor and the fifth resistor respectively; the gate of the fourth PMOS tube is connected to the negative electrode of the third capacitor and the sixth resistor respectively; The fifth resistor and the sixth resistor are connected to each other and receive a bias voltage; The drains of the third PMOS tube and the fourth PMOS tube are grounded.
9. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 8, characterized in that: The transconductance of the second NMOS tube and the third NMOS tube is equal to the transconductance of the third PMOS tube and the fourth PMOS tube.
10. The noise cycle voltage controlled oscillator based on switch coupled inductance according to claim 1, characterized in that: The coupling coefficient between the primary coil and the secondary coil is 0.2.