Control voltage generation method and circuit
By using an adaptive temperature-compensated control voltage generation method, and adjusting the control current gain using the current difference between zero-temperature coefficient and positive-temperature coefficient currents, the problem of frequency variation with temperature in crystal-free oscillator circuits is solved, thereby improving frequency stability and reliability.
Patent Information
- Application Number
- CN202511468761.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-14
- Publication Date
- 2026-01-06
AI Technical Summary
The oscillation frequency of a crystalless oscillator circuit is easily affected by temperature changes, leading to unstable performance of electronic devices.
An adaptive temperature compensation method for generating control voltage is used to compensate for the difference between zero-temperature coefficient current and positive temperature coefficient current, thereby adjusting the target conversion gain of the control current to stabilize the oscillation frequency.
The oscillation frequency remains stable when the temperature changes, which improves the reliability and frequency stability of the crystalless oscillator circuit.
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Figure CN121283356A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of clock circuit technology, and in particular to a method and circuit for generating control voltage. Background Technology
[0002] In electronic devices, oscillator circuits are a crucial component, providing stable and accurate clock signals to all parts of the system to ensure normal operation. Traditional oscillator circuits rely on quartz crystals to generate oscillation signals. However, such circuits have many drawbacks. For example, the quartz crystal must be soldered onto the circuit board as an external component, increasing the size of the board and manufacturing costs. Furthermore, quartz crystal oscillator circuits are highly susceptible to vibration and shock, which can lead to frequency shifts or failure.
[0003] With the continuous development of technology, crystal-free oscillator circuits have emerged and gradually demonstrated significant advantages. Crystal-free oscillator circuits eliminate the need for external components such as quartz crystals, greatly reducing circuit size and providing strong support for the miniaturization and integration of electronic devices. Simultaneously, the elimination of expensive quartz crystal components significantly reduces circuit costs, offering a clear economic advantage in mass production. Furthermore, crystal-free oscillator circuits have relatively low power consumption, which can effectively extend the battery life of applications with strict power consumption requirements, such as portable electronic devices.
[0004] However, crystal-free oscillators are not without their flaws. The stability of their oscillation frequency is affected by a variety of factors, with temperature variation being a key one. The semiconductor devices in crystal-free oscillators are extremely sensitive to temperature; even with a constant control signal, the oscillation frequency will change with temperature, severely impacting the performance of electronic devices. Summary of the Invention
[0005] In view of the above problems, the purpose of this application is to provide a control voltage generation method and circuit that can realize adaptive temperature compensation of control voltage so that the oscillation frequency of voltage-controlled oscillator circuit does not change with temperature.
[0006] According to one aspect of the present invention, a control voltage generation method is provided, wherein a voltage-controlled oscillator circuit provides an oscillation frequency based on the control voltage, the control voltage generation method comprising: obtaining a first differential current between a zero temperature coefficient current and a first positive temperature coefficient current; compensating the first differential current with a compensation current to provide a control current; and providing the control voltage based on the control current and its corresponding target conversion gain, wherein the compensation current varies with temperature in a first temperature range and a third temperature range, is zero in a second temperature range, and when the control voltage is constant, the oscillation frequency changes with temperature at a greater rate in the first temperature range and the third temperature range than at the greater rate in the second temperature range.
[0007] Optionally, the target conversion gain of the control current in the first temperature range and the third temperature range is greater than the target conversion gain in the second temperature range.
[0008] Optionally, the step of generating the compensation current includes: obtaining a second differential current between a second positive temperature coefficient current and a zero temperature coefficient current; obtaining a third differential current between a third positive temperature coefficient current and a zero temperature coefficient current; and obtaining the compensation current based on the second differential current and the third differential current, wherein, at a first set temperature, the second positive temperature coefficient current and the zero temperature coefficient current are equal, at a second set temperature, the third positive temperature coefficient current and the zero temperature coefficient current are equal, and the first set temperature ≤ the temperature of the second temperature range ≤ the second set temperature.
[0009] Optionally, the step of obtaining the compensation current based on the second differential current and the third differential current includes: copying one of the second differential current and the third differential current to provide a first intermediate current; copying the other of the second differential current and the third differential current to provide a second intermediate current; and providing the compensation current based on the difference current between the first intermediate current and the second intermediate current, wherein, in the first temperature range and the third temperature range, the compensation current has an opposite trend to the oscillation frequency when the control voltage remains constant.
[0010] Optionally, the control voltage generation method further includes: replicating the first positive temperature coefficient current to obtain the second positive temperature coefficient current; and replicating the first positive temperature coefficient current to obtain the third positive temperature coefficient current.
[0011] Optionally, the conversion gain corresponding to each of the control currents is obtained through a pre-calibration test, the calibration test including: at a second set temperature, adjusting the conversion gain of the control current until the oscillation frequency is a set value to obtain a target conversion gain of the control current in the second temperature range; at a third set temperature, adjusting the conversion gain of the control current until the oscillation frequency is the set value to obtain a target conversion gain of the control current in the third temperature range; and at a fourth set temperature, adjusting the conversion gain of the control current until the oscillation frequency is the set value to obtain a target conversion gain of the control current in the first temperature range, wherein the temperature of the first temperature range is less than the first set temperature, the fourth set temperature falls within the first temperature range, the second set temperature is less than the temperature of the third temperature range, and the third set temperature falls within the third temperature range.
[0012] Optionally, the fourth set temperature is the lowest operating temperature of the voltage-controlled oscillator circuit, and the third set temperature is the highest operating temperature of the voltage-controlled oscillator circuit.
[0013] Optionally, before obtaining each of the target conversion gains, the calibration test further includes: calibrating the zero temperature coefficient current, the first positive temperature coefficient current, and the voltage-controlled oscillator circuit at a fifth set temperature, wherein the zero temperature coefficient current and the first positive temperature coefficient current are equal at the fifth set temperature, and the first set temperature ≤ the fifth set temperature < the second set temperature.
[0014] Optionally, the step of calibrating the voltage-controlled oscillator circuit includes: providing a reference voltage to the voltage-controlled oscillator circuit at the fifth set temperature to enable the voltage-controlled oscillator circuit to provide the oscillation frequency; and adjusting the settings of the voltage-controlled oscillator circuit to make the oscillation frequency the set value.
[0015] According to another aspect of the present invention, a control voltage generation circuit is provided, wherein a voltage-controlled oscillator circuit provides an oscillation frequency based on the control voltage. The control voltage generation circuit includes: a current generation circuit for providing a zero temperature coefficient current and a first positive temperature coefficient current; a current processing circuit for generating a compensation current and a first differential current between the zero temperature coefficient current and the first positive temperature coefficient current, and compensating the first differential current with the compensation current to provide a control current; and a conversion circuit for providing the control voltage based on the control current and its corresponding target conversion gain, wherein the compensation current varies with temperature in a first temperature range and a third temperature range, and is zero in a second temperature range, and when the control voltage is constant, the rate of change of the oscillation frequency in the first temperature range and the third temperature range is greater than the rate of change in the second temperature range.
[0016] Optionally, the current processing circuit includes: a first differential current generation unit for generating the first differential current; and a compensation current generation unit, including: a second differential current generation module for generating a second differential current between a second positive temperature coefficient current and the zero temperature coefficient current; a third differential current generation module for generating a third differential current between a third positive temperature coefficient current and the zero temperature coefficient current; and an output module for generating the compensation current based on the second differential current and the third differential current, wherein, at a first set temperature, the second positive temperature coefficient current and the zero temperature coefficient current are equal, at a second set temperature, the third positive temperature coefficient current and the zero temperature coefficient current are equal, and the first set temperature ≤ the temperature of the second temperature range ≤ the second set temperature.
[0017] Optionally, the output module includes: a first mirror structure for replicating one of the second differential current and the third differential current to provide a first intermediate current; and a second mirror structure for replicating the other of the second differential current and the third differential current to provide a second intermediate current, wherein the first mirror structure and the second mirror structure are connected, and their intermediate node provides the difference current between the first intermediate current and the second intermediate current as the compensation current, and in the first temperature range and the third temperature range, the compensation current has an opposite trend to the oscillation frequency when the control voltage is constant.
[0018] Optionally, the third differential current generation module includes: a first transistor, with its first terminal and control terminal short-circuited and connected to the zero temperature coefficient current; a second transistor, with its first terminal connected to the third positive temperature coefficient current, its control terminal connected to the control terminal of the first transistor, and its second terminal connected to the second terminal of the first transistor; and a third transistor, with its first terminal and control terminal short-circuited and connected to the first terminal of the second transistor, and its second terminal connected to the second terminal of the second transistor. The second differential current generation module includes: a fourth transistor, with its first terminal and control terminal short-circuited and connected to the second positive temperature coefficient current; a fifth transistor, with its first terminal connected to the zero temperature coefficient current, its control terminal connected to the control terminal of the fourth transistor, and its second terminal connected to the second terminal of the fourth transistor; and a sixth transistor, with its first terminal and control terminal short-circuited and connected to the first terminal of the fifth transistor, and its second terminal connected to the second terminal of the fifth transistor.
[0019] Optionally, the first mirror structure includes: a seventh transistor, with its control terminal connected to the control terminal of the third transistor or the sixth transistor, and its second terminal connected to the second terminal of the third transistor or the sixth transistor; an eighth transistor, with its second terminal and control terminal shorted and connected to the first terminal of the seventh transistor; and a ninth transistor, with its first terminal connected to the first terminal of the eighth transistor, its control terminal connected to the control terminal of the eighth transistor, and its second terminal providing the first current. The second mirror structure includes: a tenth transistor, with its first terminal connected to the second terminal of the ninth transistor and providing the second current, its control terminal connected to the control terminal of the third transistor or the sixth transistor, and its second terminal connected to the second terminal of the third transistor or the sixth transistor. If the oscillation frequency increases with increasing temperature when the control voltage remains constant, then the seventh transistor is connected to the sixth transistor, and the tenth transistor is connected to the third transistor; otherwise, the seventh transistor is connected to the third transistor, and the tenth transistor is connected to the sixth transistor.
[0020] Optionally, the current processing circuit further includes: a third mirror structure for replicating the first positive temperature coefficient current to obtain the second positive temperature coefficient current; and a fourth mirror structure for replicating the first positive temperature coefficient current to obtain the third positive temperature coefficient current, wherein, at a fifth set temperature, the first positive temperature coefficient current and the zero temperature coefficient current are equal, and the first set temperature ≤ the fifth set temperature < the second set temperature.
[0021] Optionally, the control voltage generation circuit further includes a register for providing a corresponding adjustment signal based on the control current to adjust the conversion circuit to the target conversion gain, wherein the target conversion gain of the control current in the first temperature range and the third temperature range is greater than the target conversion gain in the second temperature range, the lowest operating temperature of the voltage-controlled oscillator circuit is ≤ the temperature of the first range < the first set temperature, and the second set temperature < the temperature of the third temperature range is ≤ the highest operating temperature of the voltage-controlled oscillator circuit.
[0022] According to the control voltage generation method and circuit provided in this application, compensation for the control voltage is achieved by adjusting the target conversion gain of the control current. In particular, since the oscillation frequency itself exhibits a faster rate of change in the first and third temperature ranges when the control voltage remains constant, additional compensation of the control current is performed in these two temperature ranges, which is more conducive to stabilizing the oscillation frequency of the voltage-controlled oscillator circuit when the temperature changes. Therefore, the reliability of the voltage-controlled oscillator circuit, especially the crystal-free voltage-controlled oscillator circuit, can be improved. Attached Figure Description
[0023] The above and other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:
[0024] Figure 1 A schematic structural diagram of the clock generation circuit according to an embodiment of this application is shown;
[0025] Figure 2 A schematic structural diagram of the control voltage generation circuit according to an embodiment of this application is shown;
[0026] Figure 3 Show Figure 2 A schematic diagram of the medium current processing circuit;
[0027] Figure 4A Schematic structural diagrams of the compensation current generation unit in some embodiments are shown;
[0028] Figure 4B Schematic structural diagrams of the compensation current generation unit are shown in some other embodiments;
[0029] Figure 4C Schematic structural diagrams of the compensation current generation unit are shown in some other embodiments;
[0030] Figure 4D A schematic waveform diagram of the compensation current is shown;
[0031] Figure 5 A schematic flowchart of the control voltage generation method according to an embodiment of this application is shown;
[0032] Figure 6 A schematic flowchart for generating the compensation current is shown;
[0033] Figure 7 A schematic flowchart of the calibration test is shown;
[0034] Figure 8 A schematic flowchart of the calibration voltage-controlled oscillator circuit is shown;
[0035] Figure 9 A schematic diagram of the operating waveforms of the calibration voltage-controlled oscillator circuit is shown. Detailed Implementation
[0036] Various embodiments of the present application will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.
[0037] Furthermore, certain terms are used in this specification and claims to refer to specific components. Those skilled in the art will understand that manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function.
[0038] It should be understood that, in the following description, "circuit" may include single or combined hardware circuits, programmable circuits, state machine circuits, and / or elements capable of storing instructions executed by the programmable circuit. When an element or circuit is said to be "connected" to another element or "connected" between two nodes, it may be directly coupled or connected to the other element, or there may be intermediate elements; the connection between elements may be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected" to another element, it means that there are no intermediate elements between them.
[0039] Furthermore, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0040] It should also be noted that in the various methods and processes of this application, the order of the steps does not imply the order of execution, nor does it constitute any limitation on the implementation process of the embodiments of this application.
[0041] This application provides a clock generation circuit that can achieve adaptive temperature compensation, and can still provide a stable clock oscillation frequency when the operating temperature changes. Figure 1 A schematic structural diagram of the clock generation circuit according to an embodiment of this application is shown.
[0042] like Figure 1 As shown, the clock generation circuit provided in this application includes a control voltage generation circuit 100, a voltage-controlled oscillator circuit 200, a frequency divider circuit 300, and a counting circuit 400.
[0043] A control voltage generation circuit 100 provides a control voltage Vctrl. A voltage-controlled oscillator circuit 200 generates an oscillator clock clk_vco based on the control voltage Vctrl. A frequency divider circuit 300 divides the oscillator clock clk_vco to provide the required clock signal clk_div to subsequent circuits. A counting circuit 400 counts the periods of the oscillator clock clk_vco within a set duration to provide a count value Cnt. In pre-calibration tests, this count value Cnt can be used to obtain the target conversion gain corresponding to the control current in different temperature ranges (described in detail below), thereby preventing the oscillation frequency of the oscillator clock clk_vco from changing with the operating temperature.
[0044] It should be noted that the circuit structure and working principle of the voltage-controlled oscillator circuit 200, the frequency divider circuit 300, and the counting circuit 400 should be well known to those skilled in the art, and will not be specifically described in this application.
[0045] It should also be noted that, since the control voltage generation circuit 100 of this application can provide a control voltage Vctrl that adapts to temperature, thereby keeping the oscillation frequency of the oscillator clock clk_vco constant, it is particularly suitable for crystalless oscillator circuits that use LC oscillator circuits or ring oscillator circuits as free oscillation sources, and improves their reliability.
[0046] Figure 2 A schematic structural diagram of the control voltage generation circuit according to an embodiment of this application is shown. Figure 3 Show Figure 2 A schematic diagram of the medium current processing circuit; Figure 4A Schematic structural diagrams of the compensation current generation unit in some embodiments are shown; Figure 4B Schematic structural diagrams of the compensation current generation unit are shown in some other embodiments; Figure 4C Schematic structural diagrams of the compensation current generation unit are shown in some other embodiments; Figure 4D A schematic waveform diagram of the compensation current is shown below. (Followed by...) Figures 2 to 4D This application provides a detailed description of the control voltage generation circuit 100.
[0047] refer to Figure 2 The control voltage generation circuit 100 includes a current generation circuit 110, a current processing circuit 120, a conversion circuit 130, and a register 140.
[0048] The current generation circuit 110 is used to provide a zero temperature coefficient current Iztc and a first positive temperature coefficient current Iptat1. The zero temperature coefficient current Iztc does not change with temperature, while the positive temperature coefficient current Iptat1 changes proportionally with temperature. Specifically, in this application, the first positive temperature coefficient current Iptat1 is equal to the zero temperature coefficient current Iztc at a fifth set temperature.
[0049] The current processing circuit 120 is used to provide the control current Ictrl. Specifically, the control current Ictrl is provided by compensating the first differential current Id1 with the compensation current Ic.
[0050] More specifically, such as Figure 3 As shown, the current processing circuit 120 includes a first differential current generating unit 121 for generating a first differential current Id1, a compensation current generating unit 122 for generating a compensation current Ic, a third mirror structure 123 for generating a second positive temperature coefficient current Iptat2, and a fourth mirror structure 124 for generating a third positive temperature coefficient current Iptat3.
[0051] The first differential current generating unit 121 is used to generate a first differential current Id1 between the zero temperature coefficient current Iztc and the first positive temperature coefficient current Iptat1. In some embodiments, the first differential current generating unit 121 specifically includes an eleventh transistor M11 and a twelfth transistor M12. The first terminal and control terminal of the eleventh transistor M11 are shorted and connected to the first positive temperature coefficient current Iptat1, and the second terminal is connected to the second terminal of the twelfth transistor M12. The control terminal of the twelfth transistor M12 is connected to the control terminal of the eleventh transistor M11, and the first terminal of the twelfth transistor M12 is connected to the zero temperature coefficient current and used to provide the first differential current Id1.
[0052] The third mirror structure 123 and the fourth mirror structure 124 can replicate the first positive temperature coefficient current Iptat1 at different ratios to provide the second positive temperature coefficient current Iptat2 and the third positive temperature coefficient current Iptat3. Specifically, at the first set temperature, the second positive temperature coefficient current Iptat2 is equal to the zero temperature coefficient current Iztc, and at the second set temperature, the third positive temperature coefficient current Iptat3 is equal to the zero temperature coefficient current Iztc. The lowest operating temperature of the voltage-controlled oscillator circuit 200 is ≤ the temperature of the first temperature range < the first set temperature ≤ the temperature of the second temperature range ≤ the second set temperature < the temperature of the third temperature range ≤ the highest operating temperature of the voltage-controlled oscillator circuit 200. Furthermore, when the control voltage Vctrl remains constant, the rate of change of the oscillation frequency in the first and third temperature ranges is greater than the rate of change in the second temperature range. Simultaneously, when the control voltage Vctrl remains constant, the oscillation frequency exhibits a linear or approximately linear change in the second temperature range. In some embodiments, the first set temperature ≤ the fifth set temperature < the second set temperature. For example, the first set temperature and the fifth set temperature are equal and are at room temperature (e.g., 20°C).
[0053] The compensation current generation unit 122 includes a second differential current generation module 11a, a third differential current generation module 11b, and an output module 12. The second differential current generation module 11a generates a second differential current Id2 based on a second positive temperature coefficient current Iptat2 and a zero temperature coefficient current Iztc. The third differential current generation module 11b generates a third differential current Id3 based on a third positive temperature coefficient current Iptat3 and a zero temperature coefficient current Iztc. The output module 12 provides a compensation current Ic based on the second differential current Id2 and the third differential current Id3.
[0054] Specifically, the output module 12 includes a first mirror structure 12a and a second mirror structure 12b. The first mirror structure 12a is used to replicate one of the second differential current Id2 and the third differential current Id3 to provide a first intermediate current I1, and the second mirror structure 12b is used to replicate the other of the second differential current Id2 and the third differential current Id3 to provide a second intermediate current I2. The first mirror structure 12a and the second mirror structure 12b are connected, and their intermediate node provides the difference current between the first intermediate current I1 and the second intermediate current I2 as a compensation current Ic. This ensures that in the first and third temperature ranges, the compensation current Ic exhibits an opposite trend to the oscillation frequency when the control voltage Vctrl remains constant; in the second temperature range, the compensation current Ic is 0.
[0055] In some embodiments, when the control voltage Vctrl remains constant, the oscillation frequency decreases with increasing temperature. Therefore, the compensation current generation unit 122 can be as follows: Figure 4AAs shown in 122a. Specifically, the third differential current generation module 11b includes a first transistor M1, a second transistor M2, and a third transistor M3. The first terminal of the first transistor M1 is shorted to its control terminal and connected to a zero temperature coefficient current Iztc. The first terminal of the second transistor M2 is connected to a third positive temperature coefficient current Iptat3, its control terminal is connected to the control terminal of the first transistor M1, and its second terminal is connected to the second terminal of the first transistor M1. The first terminal of the third transistor M3 is shorted to its control terminal and connected to the first terminal of the second transistor M2, and its second terminal is connected to the second terminal of the second transistor M2. The second differential current generation module 11a includes a fourth transistor M4, a fifth transistor M5, and a sixth transistor M6. The first terminal of the fourth transistor M4 is shorted to its control terminal and connected to a second positive temperature coefficient current Iptat2. The first terminal of the fifth transistor M5 is connected to a zero temperature coefficient current Iztc, its control terminal is connected to the control terminal of the fourth transistor M4, and its second terminal is connected to the second terminal of the fourth transistor M4. The first terminal of the sixth transistor M6 is shorted to its control terminal and connected to the first terminal of the fifth transistor M5, and its second terminal is connected to the second terminal of the fifth transistor M5.
[0056] The first mirror structure 12a includes a seventh transistor M7, an eighth transistor M8, and a ninth transistor M9. The control terminal of the seventh transistor M7 is connected to the control terminal of the third transistor M3, and its second terminal is connected to the second terminal of the third transistor M3. The second terminal and control terminal of the eighth transistor M8 are shorted and connected to the first terminal of the seventh transistor M7. The first terminal of the ninth transistor M9 is connected to the first terminal of the eighth transistor M8, its control terminal is connected to the control terminal of the eighth transistor M8, and its second terminal provides a first intermediate current I1. The second mirror structure 12b includes a tenth transistor M10. The first terminal of the tenth transistor M10 is connected to the second terminal of the ninth transistor M9 and provides a second intermediate current I2. Its control terminal is connected to the control terminal of the sixth transistor M6, and its second terminal is connected to the second terminal of the sixth transistor M6.
[0057] In some embodiments, when the control voltage Vctrl remains constant, the oscillation frequency increases with increasing temperature. Therefore, the compensation current generation unit 122 can be as follows: Figure 4B As shown in 122b. Specifically, as Figure 4B As shown, the third differential current generation module 11b also includes the first transistor M1, the second transistor M2, and the third transistor M3. The second differential current generation module 11a also includes the fourth transistor M4, the fifth transistor M5, and the sixth transistor M6. The first mirror structure 12a also includes the seventh transistor M7, the eighth transistor M8, and the ninth transistor M9. The second mirror structure 12b also includes the tenth transistor M10. Furthermore, in Figure 4A and Figure 4B As shown, the connection relationships of the transistors within a single module are consistent. (And...) Figure 4AThe difference between the compensation current generating unit 122a shown is that, in Figure 4B In the compensation current generation unit 122b shown, the second differential current generation module 11a is connected to the first mirror structure 12a, and the third differential current generation module 11b is connected to the second mirror structure 12b. Specifically, the control terminal of the seventh transistor M7 is connected to the control terminal of the sixth transistor M6, and the second terminal of the seventh transistor M7 is connected to the second terminal of the sixth transistor M6. The control terminal of the tenth transistor M10 is connected to the control terminal of the third transistor M3, and the second terminal of the tenth transistor M10 is connected to the second terminal of the third transistor M3.
[0058] Furthermore, in order to improve the universality of the compensation current generation unit. Figure 4C Schematic structural diagrams of the compensation current generation unit 122c in some other embodiments are also shown. The compensation current generation unit 122c includes two differential current generation modules 11c and 11d and an output module 12. The differential current generation module 11c is connected to the first mirror structure 12a, and the differential current generation module 11d is connected to the second mirror structure 12b. Figure 4C In the compensation current generation unit 122c shown, the output unit 12 can be... Figure 4A and Figure 4B The embodiments shown are the same, and will not be described in detail here.
[0059] and Figure 4A and Figure 4B The difference between the illustrated embodiment and the one shown is that, in Figure 4C In the illustrated embodiment, the differential current generation module 11c includes transistors Ma, Mb, and Mc. The differential current generation module 11d includes transistors Md, Me, and Mf. The first terminal of transistor Ma is connected to the zero temperature coefficient current Iztc via a first switch K1 and to the second positive temperature coefficient current Iptat2 via a second switch K2. The first terminal of transistor Mb is connected to the third positive temperature coefficient current Iptat3 via a third switch K3 and to the zero temperature coefficient current Iztc via a fourth switch K4. The control terminal of transistor Mc is connected to the control terminal of the seventh transistor M7, and its second terminal is connected to the second terminal of the seventh transistor M7. Furthermore, the connection relationships between transistors Ma, Mb, and Mc are the same as those between the first transistor M1, the second transistor M2, and the third transistor M3.
[0060] Transistor Md's first terminal is connected to the second positive temperature coefficient current Iptat2 via the fifth switch K5, and to the zero temperature coefficient current Iztc via the sixth switch K6. Transistor Me's first terminal is connected to the zero temperature coefficient current Iztc via the seventh switch K7, and to the third positive temperature coefficient current Iptat3 via the eighth switch K8. Transistor Mf's control terminal is connected to the control terminal of the tenth transistor M10, and its second terminal is connected to the second terminal of the tenth transistor M10. Furthermore, the connection relationships between transistors Md, Me, and Mf are the same as those between the first transistor M1, the second transistor M2, and the third transistor M3.
[0061] The first switch K1, the third switch K3, the fifth switch K5, and the seventh switch K7 have the same switching state; the second switch K2, the fourth switch K4, the sixth switch K6, and the eighth switch K8 have the same switching state, and the switching states of the first switch K1 and the second switch K2 are opposite. Therefore, when the first, third, fifth, and seventh switches are closed, the second, fourth, sixth, and eighth switches are open, and the differential current generating module 11c can be regarded as the third differential current generating module 11b; the differential current generating module 11d can be regarded as the second differential current generating module 11a. At this time, Figure 4C The compensation current generation unit 122c shown can be regarded as Figure 4A The compensation current generating unit 122a is shown. When switches 1, 3, 5, and 7 are open, switches 2, 4, 6, and 8 are closed. Differential current generating module 11c can be considered as the second differential current generating module 11a; differential current generating module 11d can be considered as the third differential current generating module 11b. At this time, Figure 4C The compensation current generation unit 122c shown can be regarded as Figure 4B The compensation current generating unit 122b is shown. In other words, by adjusting the switching states of the first to eighth switches, the compensation current generating unit 122c can be adapted to different oscillation frequency variation scenarios, thus giving it better versatility.
[0062] It should be noted that, in cases such as Figures 4A to 4C In the compensation current generation unit shown, the replication ratio of the first mirror structure 12a can be the first replication ratio, and the replication ratio of the second mirror structure 12b can be the second replication ratio. By adjusting the first replication ratio and the second replication ratio, the slope of the compensation current Ic can be further adjusted so that the change of the compensation current Ic is more accurate.
[0063] Figure 4D The third differential current Id3, the second differential current Id2, and others are shown respectively. Figure 4A The compensation current Ic (A) provided by the compensation current generation unit 122a and Figure 4B The compensation current Ic(B) provided by the compensation current generation unit 122b is as follows. Figure 4D As shown, the third differential current Id3 is zero when the temperature is less than or equal to the second set temperature t2, and increases with increasing temperature when the temperature is greater than the second set temperature t2. The second differential current Id2 decreases with increasing temperature when the temperature is less than the first set temperature t1, and is zero when the temperature is greater than or equal to the first set temperature t1. Therefore, if the oscillation frequency decreases with increasing temperature while the control voltage Vctrl remains constant, the third differential current Id3 can be replicated to provide the first intermediate current I1, thereby increasing the compensation current Ic with increasing temperature in the first temperature range T1 and the third temperature range T3, as shown by curve Ic(A). If the oscillation frequency increases with increasing temperature while the control voltage Vctrl remains constant, the second differential current Id2 can be replicated to provide the first intermediate current I1, thereby decreasing the compensation current Ic with increasing temperature in the first temperature range T1 and the third temperature range T3, as shown by curve Ic(B). In the second temperature range T2, the compensation current Ic is always 0.
[0064] In some embodiments, the temperature of the first temperature range may be less than the first set temperature, and the fourth set temperature may fall within the first temperature range; the second set temperature may be less than the temperature of the third temperature range, and the third set temperature may fall within the third temperature range.
[0065] In a preferred embodiment, the third set temperature is the maximum temperature of the third temperature range (specifically, it can be the highest operating temperature of the voltage-controlled oscillator circuit), and the fourth set temperature is the minimum temperature of the first temperature range (specifically, it can be the lowest operating temperature of the voltage-controlled oscillator circuit), which is more conducive to improving calibration accuracy. That is, the temperature range can be divided according to the first set temperature, the second set temperature, and the highest and lowest operating temperatures of the voltage-controlled oscillator circuit to obtain the first, second, and third temperature ranges. Furthermore, as mentioned above, when the control voltage remains constant, the oscillation frequency changes linearly or approximately linearly in the second temperature range. Therefore, the aforementioned first and second set temperatures can be selected based on the trend of the oscillation frequency change when the control voltage remains constant.
[0066] More specifically, taking automotive-grade chips as an example, the maximum operating temperature of the voltage-controlled oscillator circuit 200 is, for example, 125℃, and the minimum operating temperature is, for example, -40℃. Furthermore, when the control voltage Vctrl remains constant, the oscillation frequency exhibits an approximately linear variation within the range of 20℃ to 80℃. Therefore, the first and fifth set temperatures can be selected as 20℃, the second set temperature as 80℃, the third set temperature as 125℃, and the fourth set temperature as -40℃.
[0067] The conversion circuit 130 is used to provide a control voltage Vctrl based on the control current Ictrl and its corresponding target conversion gain. In some embodiments, the target conversion gain of the control current Ictrl in the first temperature range and the third temperature range is greater than the target conversion gain in the second temperature range.
[0068] The target conversion gain corresponding to the control current Ictrl in different temperature ranges can be obtained through pre-calibration testing (described in detail below) and stored in register 140. When the control voltage generation circuit 100 is operating normally, register 140 provides an adjustment signal Sr based on the control current Ictrl to adjust the gain of the conversion circuit 130 to the corresponding target conversion gain.
[0069] As an example, the conversion circuit 130 can be a transimpedance amplifier (TIA), in which case the resistance value of the resistor in the TIA can be adjusted according to the adjustment signal Sr, thereby adjusting the gain of the conversion circuit 130.
[0070] According to the control voltage generation circuit provided in this application, compensation for the control voltage is achieved by adjusting the target conversion gain of the control current. In particular, since the oscillation frequency itself exhibits a faster rate of change in the first and third temperature ranges when the control voltage remains constant, additional compensation of the control current is performed in these two temperature ranges, which is more conducive to stabilizing the oscillation frequency of the voltage-controlled oscillator circuit under temperature changes. Therefore, the reliability of the voltage-controlled oscillator circuit, especially the crystal-free voltage-controlled oscillator circuit, can be improved.
[0071] This application also provides a control voltage generation method that can achieve adaptive temperature compensation of the control voltage so that the oscillation frequency of the voltage-controlled oscillator circuit does not change with temperature. In some embodiments, this control voltage generation method can be implemented by the control voltage generation circuit provided in the embodiments of this application.
[0072] Figure 5 A schematic flowchart of the control voltage generation method according to an embodiment of this application is shown; Figure 6 A schematic flowchart for generating the compensation current is shown; Figure 7 A schematic flowchart of the calibration test is shown; Figure 8 A schematic flowchart of the calibration voltage-controlled oscillator circuit is shown; Figure 9 A schematic waveform diagram of the calibration voltage-controlled oscillator circuit is shown below. Figures 5-9 The control voltage generation method provided in this application is described in detail.
[0073] like Figure 5 As shown, the control voltage generation method provided in this application includes:
[0074] Step S11: Obtain the first differential current between the zero temperature coefficient current and the positive temperature coefficient reference current;
[0075] Step S12, the first differential current is compensated by a compensation current to provide control current; and
[0076] Step S13: Provide control voltage based on control current and its corresponding target conversion gain.
[0077] When the control voltage remains constant, the oscillation frequency changes at a greater rate with temperature in the first and third temperature ranges than in the second temperature range. The compensation current changes with temperature in the first and third temperature ranges, and is zero in the second temperature range.
[0078] Furthermore, in some embodiments, when the control voltage remains constant, the oscillation frequency has a greater rate of change in the first temperature range and the third temperature range, so the target conversion gain of the control current corresponding to the first temperature range and the third temperature range is greater than the target conversion gain corresponding to the second temperature range.
[0079] According to the control voltage generation method provided in this application, compensation for the control voltage is achieved by adjusting the target conversion gain of the control current. In particular, since the oscillation frequency itself exhibits a faster rate of change in the first and third temperature ranges when the control voltage remains constant, additional compensation of the control current is performed in these two temperature ranges, which is more conducive to stabilizing the oscillation frequency of the voltage-controlled oscillator circuit under temperature changes. Therefore, the reliability of the voltage-controlled oscillator circuit, especially the crystal-free voltage-controlled oscillator circuit, can be improved.
[0080] Furthermore, such as Figure 6 As shown, the steps for generating the compensation current include:
[0081] Step S21: Obtain the second differential current between the second positive temperature coefficient current and the zero temperature coefficient current;
[0082] Step S22: Obtain the third differential current between the third positive temperature coefficient current and the zero temperature coefficient current;
[0083] Step S23: Obtain the compensation current based on the second differential current and the third differential current.
[0084] Specifically, at the first set temperature, the second positive temperature coefficient current is equal to the zero temperature coefficient current, and at the second set temperature, the third positive temperature coefficient current is equal to the zero temperature coefficient current. Therefore, the third differential current is zero when the temperature is less than or equal to the second set temperature, and increases with increasing temperature when the temperature is greater than the second set temperature. The second differential current decreases with increasing temperature when the temperature is less than the first set temperature, and is zero when the temperature is greater than or equal to the first set temperature.
[0085] Specifically, the minimum operating temperature of the voltage-controlled oscillator (VCO) circuit is ≤ the temperature of the first temperature range < the first set temperature ≤ the temperature of the second temperature range ≤ the second set temperature < the temperature of the third temperature range ≤ the maximum operating temperature of the VCO circuit. In other words, the temperature range can be divided into three temperature ranges based on the first set temperature, the second set temperature, and the maximum and minimum operating temperatures of the VCO circuit. Furthermore, when the control voltage remains constant, the oscillation frequency exhibits a linear or approximately linear change in the second temperature range. Therefore, the first and second set temperatures can be selected based on the trend of the oscillation frequency change when the control voltage remains constant.
[0086] In some embodiments, the second positive temperature coefficient current and the third positive temperature coefficient current can be generated based on the first positive temperature coefficient current. Therefore, before generating the compensation current, the control voltage generation method provided in this application further includes: replicating the first positive temperature coefficient current to generate the second positive temperature coefficient current; and replicating the first positive temperature coefficient current to generate the third positive temperature coefficient current.
[0087] Step S23 may specifically include: replicating one of the second differential current and the third differential current to provide a first intermediate current; replicating the other of the second differential current and the third differential current to provide a second intermediate current; and providing a compensation current based on the difference current between the first intermediate current and the second intermediate current, wherein, in the first temperature range and the third temperature range, the compensation current has an opposite trend to the oscillation frequency when the control voltage remains constant.
[0088] Specifically, if the oscillation frequency decreases with increasing temperature while the control voltage remains constant, a third differential current can be replicated to provide the first intermediate current, thereby increasing the compensation current with increasing temperature in both the first and third temperature ranges. If the oscillation frequency increases with increasing temperature while the control voltage remains constant, a second differential current can be replicated to provide the first intermediate current, thereby decreasing the compensation current with increasing temperature in both the first and third temperature ranges. In the second temperature range, the compensation current is always 0.
[0089] Furthermore, in some embodiments, it can be done by means of, for example Figure 7 The calibration test steps shown obtain the conversion gain corresponding to the control current. These include:
[0090] Step S31: Calibrate the zero temperature coefficient current, reference current, and voltage-controlled oscillator circuit at the fifth set temperature.
[0091] Step S32: At the second set temperature, adjust the conversion gain of the control current until the oscillation frequency is the set value, so as to obtain the target conversion gain of the control current in the second temperature range.
[0092] Step S33: At the third set temperature, adjust the conversion gain of the control current until the oscillation frequency is the set value, so as to obtain the target conversion gain of the control current in the third temperature range.
[0093] Step S34: At the fourth set temperature, adjust the conversion gain of the control current until the oscillation frequency is the set value, so as to obtain the target conversion gain of the control current in the first temperature range.
[0094] Wherein, the first set temperature ≤ the fifth set temperature < the second set temperature. For example, the first set temperature and the fifth set temperature are equal and are room temperature (room temperature is, for example, 20°C).
[0095] Furthermore, if the temperature in the first temperature range is less than the first set temperature, the fourth set temperature falls within the first temperature range; if the second set temperature is less than the temperature in the third temperature range, the third set temperature falls within the third temperature range.
[0096] In a preferred embodiment, the third set temperature is the maximum temperature of the third temperature range (specifically, it can be the highest operating temperature of the voltage-controlled oscillator circuit), and the fourth set temperature is the minimum temperature of the first temperature range (specifically, it can be the lowest operating temperature of the voltage-controlled oscillator circuit), which is more conducive to improving calibration accuracy.
[0097] More specifically, taking automotive-grade chips as an example, the maximum operating temperature of a voltage-controlled oscillator circuit is, for example, 125℃, and the minimum operating temperature is, for example, -40℃. Furthermore, when the control voltage Vctrl remains constant, the oscillation frequency exhibits an approximately linear variation within the range of 20℃ to 80℃. Therefore, the first and fifth set temperatures can be set to 20℃, the second set temperature to 80℃, the third set temperature to 125℃, and the fourth set temperature to -40℃.
[0098] The steps for calibrating a voltage-controlled oscillator circuit include, for example: Figure 8 Steps S41 and S42 are shown.
[0099] Step S41: Provide a reference voltage to the voltage-controlled oscillator circuit at the fifth set temperature so that the voltage-controlled oscillator circuit provides the oscillation frequency.
[0100] Step S42: Adjust the settings of the voltage-controlled oscillator circuit until the oscillation frequency reaches the set value.
[0101] The voltage-controlled oscillator circuit can be an LC oscillator circuit or a ring oscillator circuit. Taking an LC oscillator circuit as an example, step S42 can involve adjusting the capacitance value of the capacitor array in the LC oscillator circuit to adjust the oscillation frequency. When the clock frequency reaches the set value, the calibration of the voltage-controlled oscillator circuit is completed.
[0102] Figure 9 The diagram shows a schematic of the operating waveforms during the calibration of the voltage-controlled oscillator circuit. For example... Figure 9 As shown, the oscillation frequency of the oscillator clock can be adjusted by regulating the LC bandsel setting of the voltage-controlled oscillator circuit. Specifically, after the voltage-controlled oscillator circuit starts oscillating, the count value CNT provided by the counting circuit in the clock generation circuit is reset according to the RESET signal. After the count value CNT is reset, an enable signal is provided with an effective level to control the counting circuit to start counting the elapsed clock cycles. It should be noted that the effective level of the enable signal has the same width in different counting stages. When the enable signal returns to an inactive level, the count value CNT is read and compared with the set value. If they are equal, the calibration is completed; if they are not equal, the voltage-controlled oscillator circuit setting is adjusted and the next counting stage is entered.
[0103] According to the control voltage generation method and circuit provided in this application, compensation for the control voltage is achieved by adjusting the target conversion gain of the control current. In particular, since the oscillation frequency itself exhibits a faster rate of change in the first and third temperature ranges when the control voltage remains constant, additional compensation of the control current is performed in these two temperature ranges, which is more conducive to stabilizing the oscillation frequency of the voltage-controlled oscillator circuit under temperature changes. Therefore, the reliability of the voltage-controlled oscillator circuit, especially the crystal-free voltage-controlled oscillator circuit, can be improved.
[0104] As described above, these embodiments of this application do not exhaustively cover all details, nor do they limit this application to specific embodiments. Clearly, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this application, thereby enabling those skilled in the art to effectively utilize this application and its modifications. The scope of protection of this application should be determined by the scope defined in the claims of this application.
Claims
1. A control voltage generation method, wherein, A voltage-controlled oscillator provides an oscillation frequency according to a control voltage, and a method for generating the control voltage comprises: obtaining a first difference current between a zero-temperature-coefficient current and a first positive-temperature-coefficient current; compensating the first difference current by a compensation current to provide a control current; and providing the control voltage according to the control current and a corresponding target conversion gain of the control current, wherein the compensation current varies with temperature in a first temperature interval and a third temperature interval, and is zero in a second temperature interval, the oscillation frequency varies with temperature at a rate greater in the first temperature interval and the third temperature interval than in the second temperature interval when the control voltage is constant.
2. The control voltage generation method of claim 1, wherein, the target conversion gain corresponding to the control current is greater in the first temperature interval and the third temperature interval than in the second temperature interval.
3. The control voltage generation method of claim 1, wherein, The step of generating the compensation current comprises: obtaining a second difference current between a second positive-temperature-coefficient current and the zero-temperature-coefficient current; obtaining a third difference current between a third positive-temperature-coefficient current and the zero-temperature-coefficient current; and obtaining the compensation current according to the second difference current and the third difference current, wherein the second positive-temperature-coefficient current is equal to the zero-temperature-coefficient current at a first set temperature, and the third positive-temperature-coefficient current is equal to the zero-temperature-coefficient current at a second set temperature, the first set temperature ≤ the temperature of the second temperature interval ≤ the second set temperature.
4. The control voltage generation method of claim 3, wherein, The step of obtaining the compensation current according to the second difference current and the third difference current comprises: copying one of the second difference current and the third difference current to provide a first intermediate current; copying the other of the second difference current and the third difference current to provide a second intermediate current; and providing the compensation current according to a difference current between the first intermediate current and the second intermediate current, wherein in the first temperature interval and the third temperature interval, the compensation current has a change trend opposite to the oscillation frequency when the control voltage is constant.
5. The control voltage generation method of claim 3, wherein, The method for generating the control voltage further comprises: copying the first positive-temperature-coefficient current to obtain the second positive-temperature-coefficient current; and copying the first positive-temperature-coefficient current to obtain the third positive-temperature-coefficient current.
6. The control voltage generation method of claim 3, wherein, The conversion gain corresponding to each of the control currents is obtained by a pre-calibration test, the calibration test comprises: adjusting the conversion gain of the control current until the oscillation frequency is a set value at the second set temperature to obtain the target conversion gain of the control current in the second temperature interval; adjusting the conversion gain of the control current until the oscillation frequency is the set value at a third set temperature to obtain the target conversion gain of the control current in the third temperature interval; and adjusting the conversion gain of the control current until the oscillation frequency is the set value at a fourth set temperature to obtain the target conversion gain of the control current in the first temperature interval, wherein the temperature of the first temperature interval < the first set temperature, and the fourth set temperature falls in the first temperature interval. The second set temperature is lower than a temperature of the third temperature range, and the third set temperature falls in the third temperature range. 7.The control voltage generation method of claim 6, wherein, The fourth set temperature is a lowest operating temperature of the voltage-controlled oscillation circuit, The third set temperature is a highest operating temperature of the voltage-controlled oscillation circuit. 8.The control voltage generation method of claim 6, wherein, Before obtaining each target conversion gain, the calibration test further comprises: calibrating the zero-temperature coefficient current, the first positive-temperature coefficient current, and the voltage-controlled oscillation circuit at a fifth set temperature, wherein the zero-temperature coefficient current and the first positive-temperature coefficient current are equal at the fifth set temperature, and the first set temperature is less than or equal to the fifth set temperature and less than the second set temperature. 9.The control voltage generation method of claim 8, wherein, The step of calibrating the voltage-controlled oscillation circuit comprises: providing a reference voltage to the voltage-controlled oscillation circuit at the fifth set temperature to cause the voltage-controlled oscillation circuit to provide the oscillation frequency; adjusting a setting of the voltage-controlled oscillation circuit to cause the oscillation frequency to be the set value.
10. A control voltage generation circuit, wherein, A voltage-controlled oscillation circuit provides an oscillation frequency according to a control voltage, and the control voltage generation circuit comprises: a current generation circuit configured to provide a zero-temperature coefficient current and a first positive-temperature coefficient current; a current processing circuit configured to generate a compensation current and a first difference current between the zero-temperature coefficient current and the first positive-temperature coefficient current, and to compensate the first difference current by the compensation current to provide a control current; and a conversion circuit configured to provide the control voltage according to the control current and a target conversion gain corresponding to the control current, wherein the compensation current varies with temperature in a first temperature range and a third temperature range, and is zero in a second temperature range, when the control voltage is constant, a rate of change of the oscillation frequency in the first temperature range and the third temperature range is greater than a rate of change of the oscillation frequency in the second temperature range. 11.The control voltage generation circuit of claim 10, wherein, The current processing circuit comprises: a first difference current generation unit configured to generate the first difference current; and a compensation current generation unit comprising: a second difference current generation module configured to generate a second difference current between a second positive-temperature coefficient current and the zero-temperature coefficient current; a third difference current generation module configured to generate a third difference current between a third positive-temperature coefficient current and the zero-temperature coefficient current; and an output module configured to generate the compensation current according to the second difference current and the third difference current, wherein the second positive-temperature coefficient current is equal to the zero-temperature coefficient current at a first set temperature, and the third positive-temperature coefficient current is equal to the zero-temperature coefficient current at a second set temperature, and the first set temperature is less than or equal to a temperature of the second temperature range and less than the second set temperature.
12. The control voltage generation circuit of claim 11, wherein, The output module comprises: a first mirroring structure configured to copy one of the second difference current and the third difference current to provide a first intermediate current; and a second mirroring structure configured to copy the other of the second difference current and the third difference current to provide a second intermediate current. a second mirror structure for copying another one of the second differential current and the third differential current to provide a second intermediate current, wherein the first mirror structure and the second mirror structure are connected, and a node between the two provides a differential current of the first intermediate current and the second intermediate current as the compensation current, in the first temperature interval and the third temperature interval, the compensation current and the oscillation frequency when the control voltage is unchanged have opposite trends.
13. The control voltage generation circuit of claim 12, wherein, the third differential current generation module comprises: a first transistor having a first end and a control end shorted and connected to the zero-temperature-coefficient current; a second transistor having a first end connected to the third positive-temperature-coefficient current, a control end connected to the control end of the first transistor, and a second end connected to the second end of the first transistor; and a third transistor having a first end and a control end shorted and connected to the first end of the second transistor, and a second end connected to the second end of the second transistor, the second differential current generation module comprises: a fourth transistor having a first end and a control end shorted and connected to the second positive-temperature-coefficient current; a fifth transistor having a first end connected to the zero-temperature-coefficient current, a control end connected to the control end of the fourth transistor, and a second end connected to the second end of the fourth transistor; and a sixth transistor having a first end and a control end shorted and connected to the first end of the fifth transistor, and a second end connected to the second end of the fifth transistor.
14. The control voltage generation circuit of claim 13, wherein, the first mirror structure comprises: a seventh transistor having a control end connected to the control end of the third transistor or the sixth transistor, and a second end connected to the second end of the third transistor or the sixth transistor; an eighth transistor having a second end and a control end shorted and connected to the first end of the seventh transistor; and a ninth transistor having a first end connected to the first end of the eighth transistor, a control end connected to the control end of the eighth transistor, and a second end providing the first current, the second mirror structure comprises: a tenth transistor having a first end connected to the second end of the ninth transistor and providing the second current, a control end connected to the control end of the third transistor or the sixth transistor, and a second end connected to the second end of the third transistor or the sixth transistor, wherein, if the oscillation frequency increases with temperature when the control voltage is unchanged, the seventh transistor is connected to the sixth transistor, and the tenth transistor is connected to the third transistor; otherwise, the seventh transistor is connected to the third transistor, and the tenth transistor is connected to the sixth transistor.
15. The control voltage generation circuit of claim 11, wherein, the current processing circuit further comprises: a third mirror structure for copying the first positive-temperature-coefficient current to obtain the second positive-temperature-coefficient current; and a fourth mirror structure for copying the first positive-temperature-coefficient current to obtain the third positive-temperature-coefficient current, wherein, at a fifth set temperature, the first positive-temperature-coefficient current and the zero-temperature-coefficient current are equal, and the first set temperature ≤ the fifth set temperature < the second set temperature.
16. The control voltage generation circuit of claim 11, wherein, The control voltage generating circuit further comprises: a register for providing a corresponding adjusting signal according to the control current to adjust the conversion circuit to the target conversion gain, wherein the control current corresponds to the target conversion gain in the first temperature interval and the third temperature interval is greater than the target conversion gain in the second temperature interval, the lowest working temperature of the voltage-controlled oscillation circuit ≤ the temperature of the first interval < the first set temperature, the second set temperature < the temperature of the third temperature interval ≤ the highest working temperature of the voltage-controlled oscillation circuit.