Voltage Controlled Oscillator

Abstract

The present invention discloses a voltage-controlled oscillator, which includes a current-controlled oscillator, a voltage-current conversion circuit, and a noise cancellation circuit. The current-controlled oscillator is configured to receive a bias current and generate an oscillation signal having an oscillation frequency according to the bias current. The voltage-current conversion circuit is coupled to a power supply voltage and is configured to generate a supply current according to an input voltage. The noise cancellation circuit is configured to receive a bias voltage and the supply current from the voltage-current conversion circuit, and is configured to generate a noise cancellation current in response to a change in the power supply voltage and cancel the noise cancellation current from the supply current to generate the bias current. The bias voltage of the noise cancellation circuit is coupled to an internal voltage of the voltage-current conversion circuit.

Description

Technical Field

[0001] The present invention relates to a voltage-controlled oscillator, and particularly to a voltage-controlled oscillator with a high power supply rejection ratio and high power efficiency. Background Art

[0002] A voltage-controlled oscillator (VCO) is an important and critical component in many electronic systems, and can be applied in various electronic circuit devices, such as being applied in a phase lock loop (PLL) or a clock and data recovery (CDR) circuit. Generally, a voltage-controlled oscillator can be used to generate an oscillation signal with a correct and stable oscillation frequency. However, the power supply usually brings some noises, and the power supply noises will affect the output frequency and stability of the voltage-controlled oscillator, thus resulting in a low power supply rejection ratio (PSRR) and high power consumption. Therefore, how to improve the performance of the voltage-controlled oscillator and reduce power consumption is an important issue in the current industry. Summary of the Invention

[0003] Therefore, the present invention provides a voltage-controlled oscillator with a high power supply rejection ratio and high power efficiency to solve the above problems.

[0004] The present invention discloses a voltage-controlled oscillator, including: a current-controlled oscillator configured to receive a bias current and generate an oscillation signal with an oscillation frequency according to the bias current; a voltage-current conversion circuit coupled to a power supply voltage and configured to generate a supply current according to an input voltage; and a noise cancellation circuit coupled to the power supply voltage and the voltage-current conversion circuit, configured to receive a bias voltage and the supply current from the voltage-current conversion circuit, and configured to generate a noise cancellation current in response to a change in the power supply voltage and cancel the noise cancellation current from the supply current to generate the bias current, wherein the bias voltage of the noise cancellation circuit is coupled to an internal voltage of the voltage-current conversion circuit. Description of the Drawings

[0005] Figure 1 It is a schematic diagram of a voltage-controlled oscillator according to an embodiment of the present invention.

[0006] Figure 2 is Figure 1 a schematic diagram of an embodiment of the circuit architecture of the voltage-controlled oscillator in

[0007] Figure 3 is Figure 2Schematic diagram of an embodiment of the current source in

[0008] Figure 4 Schematic diagram of an embodiment of the equivalent circuit topology of the voltage-controlled oscillator according to an embodiment of the present invention.

[0009] Figures 5 to 8 Schematic diagram of a variant embodiment of the noise cancellation circuit according to an embodiment of the present invention.

[0010] Figure 9 is Figure 1 Schematic diagram of an embodiment of another circuit architecture of the voltage-controlled oscillator in

[0011] Among them, the reference numerals are explained as follows:

[0012] 10, 90 Voltage-controlled oscillator

[0013] 102 Voltage-current conversion circuit

[0014] 1022, 1024, 1044, 802, 9022, 9024 Current source

[0015] 1026, 9026 Transistor pair

[0016] 1028, 9028 Voltage generation circuit

[0017] 104 Noise cancellation circuit

[0018] 1042 Power supply noise sensing circuit

[0019] 106 Current-controlled oscillator

[0020] Cvco Oscillation capacitor

[0021] I1, I2 Reference current

[0022] Icancel Noise cancellation current

[0023] Icco Bias current

[0024] Imain Supply current

[0025] Is Sensing current

[0026] M1 - M13, MP1 - MP4 Transistors

[0027] Vb, Vb1 Bias voltage

[0028] VDD Power supply voltage

[0029] VCO_out Oscillation signal

[0030] Vctrl Input voltage

[0031] Vint internal voltage Detailed implementation manners

[0032] Please refer to Figure 1 , Figure 1 which is a schematic diagram of a voltage-controlled oscillator (VCO) 10 according to an embodiment of the present invention. The voltage-controlled oscillator 10 can be used to generate an oscillation signal VCO_out having an oscillation frequency according to an input voltage Vctrl. The input voltage Vctrl can be provided in a digital control form or an analog control form. The applied input voltage Vctrl can determine the oscillation frequency. As Figure 1 shown, the voltage-controlled oscillator 10 includes a voltage-current conversion circuit 102, a noise cancellation circuit 104, and a current-controlled oscillator 106. The voltage-current conversion circuit 102 is coupled to a power supply voltage VDD and is configured to generate a supply current Imain according to the input voltage Vctrl. The noise cancellation circuit 104 is coupled to the power supply voltage VDD and the voltage-current conversion circuit 102. The noise cancellation circuit 104 is configured to receive a bias voltage Vb and the supply current Imain from the voltage-current conversion circuit 102. The noise cancellation circuit 104 is configured to generate a noise cancellation current Icancel in response to a change in the power supply voltage VDD, and is configured to cancel the noise cancellation current Icancel from the supply current Imain to generate a bias current Icco. The current-controlled oscillator 106 is configured to receive the bias current Icco from the noise cancellation circuit 104 and generate the oscillation signal VCO_out having an oscillation frequency according to the bias current Icoo. The oscillation frequency of the oscillation signal VCO_out can vary with the bias current Icco.

[0033] Please refer to Figure 2 , Figure 2 is Figure 1 a schematic diagram of an embodiment of the circuit architecture of the voltage-controlled oscillator 10 in. The voltage-current conversion circuit 102 includes current sources 1022 and 1024, a transistor pair 1026, and a voltage generation circuit 1028. The current source 1022 is configured to generate a reference current I1 according to the input voltage Vctrl. The input voltage Vctrl can be digital control or analog control. The current source 1024 is configured to generate a reference current I2 according to the input voltage Vctrl. The reference current I1 and the reference current I2 can be proportional. For example, the reference current I2 can be α times the reference current I1 (I2 = α * I1), where α represents a current gain of the voltage-current conversion circuit 102, and α can be equal to or less than 1.

[0034] Please refer to Figure 3 ,Figure 3 Schematic diagram of an embodiment of a current source in Figure 2 As shown in Figure 3 shown, the current source 1022 includes a transistor M5, and the current source 1024 includes a transistor M6. The transistors M5 and M6 can be metal-oxide semiconductor (MOS) transistors or other devices with similar functions. For example, as Figure 3 shown, the transistors M5 and M6 can be n-type metal-oxide semiconductor (n-type MOS, NMOS) transistors. The gate terminal of the transistor M5 is coupled to the input voltage Vctrl. The drain terminal of the transistor M5 is coupled to the transistor pair 1026 to provide a reference current I1. The gate terminal of the transistor M6 is coupled to the input voltage Vctrl. The drain terminal of the transistor M6 is coupled to the voltage generation circuit 1028 to provide a reference current I2. For example, the width-to-length (W / L) ratio of the transistor M6 can be α times that of the transistor M5, where α represents a current gain of the voltage-current conversion circuit 102, and α can be equal to or less than 1.

[0035] Please continue to refer to Figure 2 , the transistor pair 1026 is coupled to the current source 1022. The transistor pair 1026 includes transistors MP1 and MP2. The transistors MP1 and MP2 can be metal-oxide semiconductor transistors or other devices with similar functions. For example, the transistors MP1 and MP2 can be p-type metal-oxide semiconductor (p-type MOS, PMOS) transistors. The source terminal of the transistor MP1 is coupled to the power supply voltage VDD, and the gate terminal of the transistor MP1 is coupled to the drain terminal of the transistor MP1 and the gate terminal of the transistor MP2. The drain terminal of the transistor MP1 is coupled to the current source 1022. The transistor MP1 is configured to mirror the reference current I1. The source terminal of the transistor MP2 is coupled to the power supply voltage VDD, and the gate terminal of the transistor MP2 is coupled to the drain terminal and the gate terminal of the transistor MP1. The drain terminal of the transistor MP2 is coupled to the voltage generation circuit 1028. The transistor MP2 is configured to output a supply current Imain, and the supply current Imain is the mirrored reference current I1.

[0036] The voltage generation circuit 1028 is coupled to the current source 1024 and the noise cancellation circuit 104. The voltage generation circuit 1028 is configured to provide an internal voltage Vint of the voltage-current conversion circuit 102 to the noise cancellation circuit 104. The internal voltage Vint and the circuit used to generate the supply current Imain in the voltage-current conversion circuit 102 can be independent of each other. As Figure 2As shown, the voltage generation circuit 1028 includes transistors M1 and M2. Transistors M1 and M2 can be metal oxide semiconductor transistors or other devices with similar operating modes and functions. For example, transistors M1 and M2 can be P-type metal oxide semiconductor transistors. The source terminal of transistor M1 is coupled to the power supply voltage VDD. The gate terminal of transistor M1 is coupled to the drain terminal of transistor M1. The gate terminal of transistor M2 and the noise cancellation circuit 104. The drain terminal of transistor M1 is coupled to the current source 1024 to receive the reference current I2. The internal voltage Vint varies with the reference current I2. The voltage at the gate terminal of transistor M1 is the internal voltage Vint. The source terminal of transistor M2 is coupled to the drain terminal of transistor MP2 to receive the supply current Imain. The gate terminal of transistor M2 is coupled to the gate terminal of transistor M1. The drain terminal of transistor M2 is coupled to the noise cancellation circuit 104 to output the supply current Imain. In a variant embodiment, transistor M2 can be omitted or have other configuration arrangements.

[0037] To improve the efficiency of the supply power, one of the techniques that can be used is to make the supply current Imain less sensitive to changes in the power supply voltage VDD. That is to say, reduce the transconductance of the supply power. As Figure 2 shown. The supply current Imain is generated by transistor MP2 based on the power supply voltage VDD and flows through transistors MP2 and M2 to the noise cancellation circuit 104. Since transistor M2 is connected in series with transistor MP2, the output impedance seen from the drain terminal of transistor M2 in the direction of the voltage-current conversion circuit 102 is increased and the transconductance of the power supply voltage VDD is decreased. In this way, when the transconductance of the supply power (power supply voltage VDD) is reduced, the supply current Imain can be made less sensitive to supply power noise.

[0038] The noise cancellation circuit 104 includes a power supply noise sensing circuit 1042 and a current mirror 1044. The power supply noise sensing circuit 1042 is coupled to the voltage-current conversion circuit 102 and the power supply voltage VDD. The power supply noise sensing circuit 1042 is configured to receive the bias voltage Vb and the supply current Imain from the voltage-current conversion circuit 102. For example, as Figure 2As shown, the bias voltage Vb of the noise cancellation circuit 104 is coupled to the internal voltage Vint of the voltage-current conversion circuit 102. The power supply noise sensing circuit 1042 is coupled to the gate terminal of the transistor M1 to receive the internal voltage Vint as the bias voltage Vb of the power supply noise sensing circuit 1042. Since the noise cancellation circuit 104 is coupled to the gate terminal of the transistor M1, the bias voltage Vb of the voltage generation circuit 1028 can be equal to the internal voltage Vint. The bias voltage Vb (i.e., the internal voltage Vint) can be used as a control voltage or a bias voltage for the noise cancellation circuit 104. The power supply noise sensing circuit 1042 is configured to generate a sense current Is in response to a change in the power supply voltage VDD and generate the bias voltage Vb (i.e., the internal voltage Vint). The sense current Is can be determined based on the power supply voltage VDD and the bias voltage Vb (i.e., the internal voltage Vint).

[0039] The current mirror 1044 is coupled to the power supply noise sensing circuit 1042, the voltage-current conversion circuit 102, and the current controlled oscillator 106. The current mirror 1044 is configured to mirror the sense current Is onto the noise cancellation current Icancel. As Figure 2 shown, the current mirror 1044 includes transistors M3 and M4. For example, the transistors M3 and M4 can be metal oxide semiconductor transistors or other devices with similar operating modes and functions. The gate terminal of the transistor M4 is coupled to the drain terminal of the transistor M4 and the gate terminal of the transistor M3. The drain terminal of the transistor M4 is coupled to the power supply noise sensing circuit 1042. The transistor M4 is configured to mirror the sense current Is. The drain terminal of the transistor M3 is coupled to the drain terminal of the transistor M2, the voltage generation circuit 1028, and the current controlled oscillator 106. The transistor M3 is configured to generate the noise cancellation current Icancel, where the noise cancellation current Icancel is the mirrored sense current Is, and the transistor M3 is configured to cancel the noise cancellation current from the supply current Imain to generate the bias current Icco. The bias current Icco is output to the current controlled oscillator 106. The noise cancellation current Icancel can be proportional to the sense current Is. For example, the noise cancellation current Icancel can be equal to β times the sense current Is, where β represents the current gain (current ratio of the current mirror) of the current mirror 1044, and β can be equal to or greater than 1. For example, the width-to-length ratio of the transistor M3 can be β times the width-to-length ratio of the transistor M4. In one embodiment, the current gain α of the voltage-current conversion circuit 102 can be equal to or less than 1, and the current gain β of the current mirror 1044 can be equal to or greater than 1. The product of the current gain α of the voltage-current conversion circuit 102 and the current gain β of the current mirror 1044 can be equal to 1 (α * β = 1).

[0040] When the power supply voltage VDD increases, the supply current Imain increases and the power supply noise sensing circuit generates a larger noise cancellation current Icancel. At this time, the bias current Icco will become smaller. On the other hand, when the power supply voltage VDD decreases, the supply current Imain will become smaller and the power supply noise sensing circuit generates a smaller noise cancellation current Icancel. Therefore, the bias current Icco will become larger. Based on the appropriate setting of the current gain α and the current gain β, the change in the supply current caused by the supply power noise can be eliminated by the noise cancellation current. In this way, the change in the power supply voltage VDD will not affect the bias current Icco provided to the current controlled oscillator 106, and the bias current Icco can be maintained stable.

[0041] Please refer to Figure 4 , Figure 4 FIG. is a schematic diagram of an embodiment of the equivalent circuit topology of the voltage controlled oscillator 10 according to an embodiment of the present invention. The voltage-current conversion circuit 102 generates a supply current Imain. The noise cancellation circuit 104 generates a noise cancellation current Icancel in response to a change in the power supply voltage VDD and generates a bias voltage Vb (i.e., the internal voltage Vint). The noise cancellation circuit 104 cancels the noise cancellation current Icancel from the supply current Imain to generate a bias current Icco. More specifically, when the supply power is interfered by noise, the noise will be injected into the power supply voltage VDD. Since the supply current Imain is generated based on the power supply voltage VDD, the supply current Imain will fluctuate due to the influence of the power supply voltage VDD containing the supply power noise. In this case, the noise cancellation circuit 104 generates a noise cancellation current Icancel and generates a bias voltage Vb (i.e., the internal voltage Vint) in response to a change in the power supply voltage VDD to eliminate or reduce the noise influence brought by the power supply voltage VDD. As Figure 4 shown, the output result of the noise cancellation circuit 104 (i.e., the bias current Icco) can be regarded as the difference between the supply current Imain and the noise cancellation current Icancel. By subtracting the noise cancellation current Icancel from the supply current Imain to generate the bias current Icco, the noise component in the power supply voltage VDD can be removed.

[0042] To improve the efficiency of the supply power, another technique that can be used is to make the noise cancellation current Icancel more sensitive to the change in the power supply voltage VDD. That is to say, increase the transconductance of the power supply noise sensing circuit 1042. As Figure 2 and Figure 3As shown, when the transconductance of the power supply noise sensing circuit 1042 increases, the sensing current Is and the noise cancellation current Icancel will become more sensitive to the supply power noise. When the noise cancellation current Icancel becomes more sensitive to the supply power noise, the noise cancellation current Icancel will more efficiently compensate for the change in the supply power voltage VDD caused by the supply power noise. In other words, the noise cancellation circuit 104 can generate a noise cancellation current Icancel that can cancel the noise introduced by the supply power voltage VDD in the supply current Imain and can reduce the change in the supply power voltage affected by the supply power noise effect, thereby effectively improving the power supply voltage rejection ratio, power supply performance, and power efficiency of the voltage controlled oscillator.

[0043] Furthermore, the noise cancellation circuit 104 is configured to provide a bias current Icoo with low noise or no noise to the current controlled oscillator 106. The current controlled oscillator 106 is configured to receive the bias current Icco from the noise cancellation circuit 104 and generate an oscillation signal VCO_out with an oscillation frequency according to the bias current Icoo of the circuit 104. The oscillation frequency of the oscillation signal VCO_out can vary with the bias current Icco. When a bias current Icoo with low noise or no noise is adopted, the current controlled oscillator 106 will be able to generate a stable oscillation signal VCO_out that is not affected by the change in the supply power voltage VDD, thereby effectively enhancing the output stability of the voltage controlled oscillator 10. In addition, the current controlled oscillator 106 further includes an oscillation capacitor Cvco.

[0044] Please refer to Figure 5 , Figure 5 FIG. is a schematic diagram of a first variant embodiment of the noise cancellation circuit according to an embodiment of the present invention. The power supply noise sensing circuit 1042 is configured to generate a sensing current and a bias voltage Vb (i.e., internal voltage Vint) in response to a change in the supply power voltage VDD. The sensing current Is can be determined based on the supply power voltage VDD and the bias voltage Vb (i.e., internal voltage Vint). As Figure 5As shown, the power supply noise sensing circuit 1042 includes a transistor M7. The transistor M7 can be a P-type metal oxide semiconductor transistor or other devices with similar operating manners and functions. The source terminal of the transistor M7 is coupled to the power supply voltage VDD. The gate terminal of the transistor M7 is coupled to the gate terminal of the transistor M1 to receive the internal voltage Vint as the bias voltage Vb. The drain terminal of the transistor M7 is coupled to the transistor M4 of the current mirror 1044 to provide the sensing current Is. In an embodiment, the aspect ratio of the transistor M7 can be different from the aspect ratio of the transistor MP2. The transconductance of the transistor M7 can be configured based on the aspect ratio of the transistor M7. When supply power noise is introduced into the power supply voltage VDD, if the transconductance of the transistor M7 increases, the noise cancellation current Icancel and the sensing current Is will be more sensitive to the power supply voltage VDD. And when the noise cancellation current Icancel becomes more sensitive to the power supply voltage VDD, the noise cancellation current Icancel will more efficiently compensate for the change in the power supply voltage VDD caused by the supply power noise, thereby effectively improving the power supply voltage rejection ratio and efficacy of the voltage controlled oscillator 10. In addition, the sensing current Is is generated based on the power supply voltage VDD and the bias voltage Vb (i.e., the internal voltage Vint). The internal voltage Vint varies with the reference current I2. In an embodiment, the aspect ratio of the transistor M7 can be different from the aspect ratio of the transistor M1. By adjusting the aspect ratios of the transistors M1 and M7, the reference current I2 and the sensing current Is can be made non-proportional.

[0045] Please refer to Figure 6 , Figure 6 is Figure 2 a schematic diagram of a second embodiment of the power supply noise sensing circuit 1042 in Figure 6 As shown, the power supply noise sensing circuit 1042 includes a transistor M8. The transistor M8 can be an N-type metal oxide semiconductor transistor or other devices with similar operating manners and functions. The drain terminal of the transistor M8 is coupled to the power supply voltage VDD. The gate terminal of the transistor M8 is coupled to the gate terminal of the transistor M1 to receive the internal voltage Vint as the bias voltage Vb. The source terminal of the transistor M8 is coupled to the transistor M4 of the current mirror 1044 to provide the sensing current Is. In an embodiment, the aspect ratio of the transistor M8 can be different from the aspect ratio of the transistor MP2. The transconductance of the transistor M8 can be configured based on the aspect ratio of the transistor M82. When supply power noise is introduced into the power supply voltage VDD, if the transconductance of the transistor M8 increases, the noise cancellation current Icancel and the sensing current Is will be more sensitive to the power supply voltage VDD. In an embodiment, the aspect ratio of the transistor M8 can be different from the aspect ratio of the transistor M1. By adjusting the aspect ratios of the transistors M1 and M8, the reference current I2 and the sensing current Is can be made non-proportional.

[0046] Please refer to Figure 7 , Figure 7 as Figure 2 a schematic diagram of a third embodiment of the power supply noise sensing circuit 1042 in Figure 7 . As shown, the power supply noise sensing circuit 1042 includes transistors M9 and M10. The source terminal of transistor M9 is coupled to the power supply voltage VDD. The gate terminal of transistor M9 is coupled to the gate terminal of transistor M1 to receive the internal voltage Vint as the bias voltage Vb. The drain terminal of transistor M9 is coupled to the source terminal of transistor M10. The gate terminal of transistor M10 is coupled to the bias voltage Vb1. The drain terminal of transistor M10 is coupled to transistor M4 of the current mirror 1044 to provide the sensing current Is.

[0047] Figure 8 as Figure 2 a schematic diagram of a fourth embodiment of the power supply noise sensing circuit 1042 in Figure 8 . As shown, the power supply noise sensing circuit 1042 includes transistors M11 - M13 and a current source 802. The source terminal of transistor M11 is coupled to the power supply voltage VDD. The gate terminal of transistor M9 is coupled to the gate terminal of transistor M1 to receive the internal voltage Vint as the bias voltage Vb. The drain terminal of transistor M11 is coupled to the gate terminal of transistor M13 and the source terminal of transistor M12. The source terminal of transistor M13 is coupled to the power supply voltage VDD. The drain terminal of transistor M13 is coupled to the current source 802 and the gate terminal of transistor M12. The drain terminal of transistor M12 is coupled to transistor M4 of the current mirror 1044 to provide the sensing current Is.

[0048] Please refer to Figure 9 , Figure 9 as Figure 1 a schematic diagram of another embodiment of the circuit architecture of the voltage - controlled oscillator 10 in Figure 9 . As shown, a voltage - current conversion circuit variation design is applied in the voltage - controlled oscillator 90. Figure 9 The architecture of the voltage - controlled oscillator 90 shown is similar to Figure 2 the architecture of the voltage - controlled oscillator 10 shown. Figure 9 The voltage - controlled oscillator 90 in Figure 2 and the voltage - controlled oscillator 10 in Figure 9 with components having the same name have similar operating manners and functions, and the connection relationships of these components are as Figure 2 shown. Different from Figure 9The voltage-controlled oscillator 90 includes a voltage-current conversion circuit 902. The voltage-current conversion circuit 902 includes current sources 9022 and 9024, a transistor pair 9026, and a voltage generation circuit 9028. The current source 9022 is configured to generate a supply current Imain according to an input voltage Vctrl. The current source 9024 is configured to generate a reference current I3 according to the input voltage Vctrl. The reference current I3 may be proportional to the supply current Imain. For example, the reference current I3 may be α times the supply current Imain (I3 = α * Imain), where α represents a current gain of the voltage-current conversion circuit 902, and α may be equal to or less than 1. The current sources 9022 and 9024 may be implemented using P-type metal oxide semiconductor transistors. The transistor pair 9026 is coupled to the current source 9024. The transistor pair 9026 includes transistors MP3 and MP4. For example, the transistors MP3 and MP4 may be metal oxide semiconductor transistors or other devices with similar functions. The drain terminal of the transistor MP3 is coupled to the current source 9024 and is configured to mirror the reference current I3. The transistor MP4 is configured to output a reference current I4 (the mirrored reference current I3). The voltage generation circuit 9028 is coupled to the current source 9026 and the noise cancellation circuit 104. The voltage generation circuit 9028 is configured to provide an internal voltage Vint of the voltage-current conversion circuit 902 to the noise cancellation circuit 104. In an embodiment, the current gain α of the voltage-current conversion circuit 902 may be equal to or less than 1, and the current gain (current ratio of the current mirror) β of the current mirror 1044 may be equal to or greater than 1. The product of the current gain α of the voltage-current conversion circuit 902 and the current gain β of the current mirror 1044 may be equal to 1.

[0049] In summary, the embodiments of the present invention can generate a noise cancellation current that can cancel out the noise introduced by the supply power in the supply current. In this way, the current-controlled oscillator can generate an oscillation signal with the correct oscillation frequency according to the low-noise or noise-free bias current, thereby effectively improving the power supply voltage rejection ratio, power supply performance, and efficiency of the voltage-controlled oscillator.

[0050] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A voltage-controlled oscillator, comprising: A current-controlled oscillator configured to receive a bias current and generate an oscillation signal having an oscillation frequency according to the bias current; A voltage-current conversion circuit coupled to a power supply voltage and configured to generate a supply current according to an input voltage, wherein the voltage-current conversion circuit includes a first current source, a second current source, and a voltage generation circuit, the first current source is configured to generate a first reference current according to the input voltage, the second current source is configured to generate a second reference current proportional to the first reference current according to the input voltage, and the voltage generation circuit is coupled to the second current source and configured to provide an internal voltage of the voltage-current conversion circuit; And A noise cancellation circuit coupled to the power supply voltage and the voltage generation circuit in the voltage-current conversion circuit, configured to receive a bias voltage and the supply current from the voltage-current conversion circuit, and configured to generate a noise cancellation current in response to a change in the power supply voltage and cancel the noise cancellation current from the supply current to generate the bias current, wherein the bias voltage of the noise cancellation circuit is coupled to the internal voltage of the voltage-current conversion circuit; Wherein, the voltage generation circuit includes a third transistor, the third transistor includes a first end, a second end, and a control end, wherein the first end of the third transistor is coupled to the second current source to receive the second reference current, the second end of the third transistor is coupled to the power supply voltage, and the control end of the third transistor is coupled to the noise cancellation circuit to provide the internal voltage.

2. The voltage-controlled oscillator according to claim 1, wherein The internal voltage is independent of a circuit that generates the supply current in the voltage-current conversion circuit.

3. The voltage-controlled oscillator according to claim 1, characterized in that The voltage-current conversion circuit includes: A first transistor pair coupled to the first current source, including: A first transistor including a first end, a second end, and a control end, wherein the first end of the first transistor is coupled to the first current source and configured to mirror the first reference current, the control end of the first transistor is coupled to the first end of the first transistor, and the second end of the first transistor is coupled to the power supply voltage; and A second transistor including a first end, a second end, and a control end, wherein the first end of the second transistor is configured to output the supply current, the supply current is the mirrored first reference current, the control end of the second transistor is coupled to the control end of the first transistor, and the second end of the second transistor is coupled to the power supply voltage.

4. The voltage-controlled oscillator according to claim 3, wherein, The voltage-current conversion circuit further includes a fourth transistor, which includes a first terminal, a second terminal, and a control terminal. Wherein the first terminal of the fourth transistor is coupled to the noise cancellation circuit to output the supply current, the control terminal of the fourth transistor is coupled to the internal voltage of the voltage generation circuit, and the second terminal of the fourth transistor is coupled to the first terminal of the second transistor to receive the supply current.

5. The voltage-controlled oscillator according to claim 3, wherein The second reference current is the product of the first reference current and a first current gain, the product of the first current gain and a second current gain related to the noise cancellation current of the noise cancellation circuit is equal to 1, and the first current gain is less than 1.

6. The voltage-controlled oscillator according to claim 1, wherein The noise cancellation circuit includes: a power supply noise sensing circuit, coupled to the voltage-current conversion circuit and the power supply voltage, and configured to receive the bias voltage from the voltage-current conversion circuit, wherein the power supply noise sensing circuit is configured to generate a sensing current in response to a change in the power supply voltage; and a current mirror, coupled to the power supply noise sensing circuit, the voltage-current conversion circuit, and the current control oscillator, and configured to mirror the sensing current onto the noise cancellation current with a second current gain.

7. The voltage-controlled oscillator according to claim 6, wherein The sensing current is determined based on the power supply voltage and the internal voltage.

8. The voltage-controlled oscillator according to claim 6, characterized in that, The power supply noise sensing circuit includes: a ninth transistor, including a first terminal, a second terminal, and a control terminal, wherein the first terminal of the ninth transistor is coupled to the power supply voltage, the control terminal of the ninth transistor is coupled to the internal voltage of the voltage-current conversion circuit, and the second terminal of the ninth transistor is coupled to the current mirror and configured to provide the sensing current.

9. The voltage-controlled oscillator according to claim 6, characterized in that, The power supply noise sensing circuit includes: a tenth transistor, including a first terminal, a second terminal, and a control terminal, wherein the first terminal of the tenth transistor is coupled to the power supply voltage, and the control terminal of the tenth transistor is coupled to the internal voltage of the voltage-current conversion circuit; and an eleventh transistor, including a first terminal, a second terminal, and a control terminal, wherein the first terminal of the eleventh transistor is coupled to the current mirror and configured to provide the sensing current, and the second terminal of the eleventh transistor is coupled to the second terminal of the tenth transistor.

10. The voltage-controlled oscillator according to claim 6, wherein, The power supply noise sensing circuit includes: a fifth current source; a twelfth transistor, including a first terminal, a second terminal, and a control terminal, wherein the first terminal of the twelfth transistor is coupled to the power supply voltage, and the control terminal of the twelfth transistor is coupled to the internal voltage of the voltage-current conversion circuit; a thirteenth transistor, including a first terminal, a second terminal, and a control terminal, wherein the control terminal of the thirteenth transistor is coupled to the second terminal of the twelfth transistor, and the second terminal of the thirteenth transistor is coupled to the fifth current source; and A fourteenth transistor includes a first terminal, a second terminal, and a control terminal, wherein the first terminal of the fourteenth transistor is coupled to the second terminal of the twelfth transistor, the control terminal of the fourteenth transistor is coupled to the second terminal of the thirteenth transistor, and the second terminal of the fourteenth transistor is coupled to the current mirror and is configured to provide the sense current.

11. A voltage-controlled oscillator, comprising: A current-controlled oscillator configured to receive a bias current and generate an oscillation signal having an oscillation frequency based on the bias current; A voltage-to-current conversion circuit coupled to a power supply voltage, wherein the voltage-to-current conversion circuit includes a third current source, a fourth current source, and a voltage generation circuit, the third current source being configured to generate a supply current based on an input voltage, the fourth current source being configured to generate a third reference current based on the input voltage, wherein the supply current is proportional to the third reference current, and the voltage generation circuit being configured to provide an internal voltage of the voltage-to-current conversion circuit; And A noise cancellation circuit coupled to the power supply voltage and the voltage generation circuit in the voltage-to-current conversion circuit, configured to receive a bias voltage and the supply current from the voltage-to-current conversion circuit, and configured to generate a noise cancellation current in response to a change in the power supply voltage and cancel the noise cancellation current from the supply current to generate the bias current, wherein the bias voltage of the noise cancellation circuit is coupled to the internal voltage of the voltage-to-current conversion circuit; Wherein the voltage generation circuit includes a seventh transistor having a first terminal, a second terminal, and a control terminal, wherein the first terminal of the seventh transistor is coupled to a second transistor pair of the voltage-to-current conversion circuit, the second terminal of the seventh transistor is coupled to the power supply voltage, and the control terminal of the seventh transistor is coupled to the noise cancellation circuit to provide the internal voltage.

12. The voltage-controlled oscillator according to claim 11, wherein, The voltage-to-current conversion circuit includes: The second transistor pair coupled to the fourth current source, including: A fifth transistor having a first terminal, a second terminal, and a control terminal, wherein the first terminal of the fifth transistor is coupled to the fourth current source and is configured to receive the third reference current, the control terminal of the fifth transistor is coupled to the first terminal of the fifth transistor, and the second terminal of the fifth transistor is coupled to a ground voltage; and A sixth transistor having a first terminal, a second terminal, and a control terminal, wherein the control terminal of the sixth transistor is coupled to the control terminal of the fifth transistor, and the second terminal of the sixth transistor is coupled to the ground voltage.

13. The voltage-controlled oscillator according to claim 11, wherein The voltage-current conversion circuit further includes an eighth transistor, which includes a first terminal, a second terminal, and a control terminal, wherein the first terminal of the eighth transistor is coupled to the noise cancellation circuit to output the supply current, the control terminal of the eighth transistor is coupled to the internal voltage of the voltage generation circuit, and the second terminal of the eighth transistor is coupled to the third current source to receive the supply current.

14. The voltage-controlled oscillator according to claim 11, wherein The third reference current is the product of the supply current and a first current gain, the product of the first current gain and a second current gain related to the noise cancellation current of the noise cancellation circuit is equal to 1, and the first current gain is less than 1.

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