Voltage control device and its system

Abstract

This application relates to the field of circuit technologies, and specifically discloses a voltage control device and its system. The device includes an operational amplifier, the first input terminal of the operational amplifier is used to receive a control signal sent by a control unit; a feedback unit, the output terminal of the operational amplifier is connected to the second input terminal of the operational amplifier through the feedback unit; a DC-DC unit, the output terminal of the operational amplifier is connected to the feedback terminal of the DC-DC unit; wherein, the feedback unit is used to collect the feedback voltage of the feedback terminal of the DC-DC unit and send the feedback voltage to the second input terminal of the operational amplifier; the operational amplifier is used to output an adjustment signal to the feedback terminal of the DC-DC unit according to the feedback voltage and the control signal to adjust the feedback voltage of the feedback terminal; the DC-DC unit is used to adjust the output voltage of the output terminal according to the feedback voltage of the feedback terminal so that the feedback voltage of the feedback terminal is restored to the reference voltage. Through the above voltage control device, a voltage signal with a linearly changing output can be achieved.

Description

Technical Field

[0001] This application relates to the field of circuit technologies, and in particular, to a voltage control device and its system. Background Art

[0002] When designing a DC-DC power supply in an existing electronic development system, in most cases, a high-voltage to low-voltage DC BUCK conversion is used. However, the output types designed in this way are generally constant voltage, constant current, or constant voltage and constant current outputs. In practical applications, there are some occasions where a linearly varying DC voltage needs to be output, while general DC-DC design schemes cannot meet the linear variation. Summary of the Invention

[0003] This application provides a voltage control device and its system, which can output a linearly varying voltage signal.

[0004] In a first aspect, this application provides a voltage control device, which includes:

[0005] An operational amplifier, whose first input terminal is used to receive a control signal sent by a control unit;

[0006] A feedback unit, the output terminal of the operational amplifier is connected to the second input terminal of the operational amplifier through the feedback unit;

[0007] A DC-DC unit, both the feedback unit and the output terminal of the operational amplifier are connected to the feedback terminal of the DC-DC unit;

[0008] Wherein, the feedback unit is used to collect the feedback voltage of the feedback terminal of the DC-DC unit and send the feedback voltage to the second input terminal of the operational amplifier;

[0009] The operational amplifier is used to output an adjustment signal to the feedback terminal of the DC-DC unit according to the feedback voltage and the control signal to adjust the feedback voltage of the feedback terminal;

[0010] The DC-DC unit is used to adjust the output voltage of the output terminal according to the feedback voltage of the feedback terminal so that the feedback voltage of the feedback terminal is restored to the reference voltage.

[0011] In an embodiment, the control signal is a pulse width modulation signal, and the voltage control device further includes a signal receiving interface, a first capacitor, and a first resistor. The signal receiving interface is connected to the first input terminal of the operational amplifier through the first resistor, and the signal receiving interface is also grounded through the first capacitor. The signal receiving interface is used to receive the control signal sent by the control unit.

[0012] In one embodiment, the feedback unit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, and a second capacitor. One end of the second resistor and one end of the third resistor are both connected to the second input terminal of the operational amplifier. The other end of the third resistor and one end of the fifth resistor are both connected to one end of the second capacitor. The other end of the fifth resistor, the other end of the second capacitor, and one end of the fourth resistor are all connected to the output terminal of the operational amplifier. The other end of the second resistor and the other end of the fourth resistor are both grounded.

[0013] In one embodiment, the first input terminal is an inverting input terminal, and the second input terminal is a non-inverting input terminal.

[0014] In one embodiment, the voltage control device further includes a first diode and a sixth resistor. The output terminal of the operational amplifier is connected to the positive electrode of the first diode, and the negative electrode of the first diode is connected to the feedback terminal of the DC-DC unit through the sixth resistor.

[0015] In one embodiment, the voltage control device further includes a third capacitor. The power supply terminal of the DC-DC unit and one end of the third capacitor are both connected to the power supply, and the other end of the third capacitor is grounded.

[0016] In one embodiment, the DC-DC unit is a non-synchronous DC-DC unit. The voltage control device further includes an output interface, a first inductor, a second diode, and a fourth capacitor. The output terminal of the DC-DC unit and the negative electrode of the second diode are both connected to one end of the first inductor. The other end of the first inductor and one end of the fourth capacitor are both connected to the output interface. The positive electrode of the second diode and the other end of the fourth capacitor are grounded. The output interface is used to output the output voltage of the DC-DC unit.

[0017] In one embodiment, the DC-DC unit is a synchronous DC-DC unit. The voltage control device further includes an output interface, a first inductor, and a fourth capacitor. The output terminal of the DC-DC unit is connected to one end of the first inductor. The other end of the first inductor and one end of the fourth capacitor are both connected to the output interface. The other end of the fourth capacitor is grounded. The output interface is used to output the output voltage of the DC-DC unit.

[0018] In a second aspect, the present application further provides a voltage control system, where the voltage control system includes: a control unit and the voltage control device provided in the above embodiment; the control unit is connected to the voltage control device, and the control unit is used to generate a control signal and send it to the voltage control device.

[0019] In one embodiment, the control unit is configured to generate pulse width modulation signals having the same amplitude and different duty cycles.

[0020] This application discloses a voltage control device and its system. The device includes an operational amplifier, where a first input terminal of the operational amplifier is configured to receive a control signal sent by a control unit; a feedback unit, where an output terminal of the operational amplifier is connected to a second input terminal of the operational amplifier through the feedback unit; a DC-DC unit, where both the feedback unit and the output terminal of the operational amplifier are connected to a feedback terminal of the DC-DC unit; wherein, the feedback unit is configured to collect a feedback voltage of the feedback terminal of the DC-DC unit and send the feedback voltage to the second input terminal of the operational amplifier; the operational amplifier is configured to output an adjustment signal to the feedback terminal of the DC-DC unit according to the feedback voltage and the control signal to adjust the feedback voltage of the feedback terminal; the DC-DC unit is configured to adjust an output voltage of an output terminal according to the feedback voltage of the feedback terminal so that the feedback voltage of the feedback terminal is restored to a reference voltage. Through the above voltage control device, a voltage signal with a linearly changing output can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 is a schematic block diagram of a voltage control device provided by an embodiment of this application;

[0023] Figure 2 is a circuit diagram of another voltage control device provided by an embodiment of this application;

[0024] Figure 3 is a circuit diagram of another voltage control device provided by an embodiment of this application;

[0025] Figure 4 is a circuit diagram of another voltage control device provided by an embodiment of this application;

[0026] Figure 5 is a circuit diagram of another voltage control device provided by an embodiment of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0028] The flowcharts shown in the accompanying drawings are only illustrative examples, and do not necessarily include all contents and operations / steps, nor do they necessarily need to be executed in the described order. For example, some operations / steps can also be decomposed, combined or partially merged, so the actual execution order may change according to the actual situation.

[0029] It should be understood that the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification of the present application and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0030] It should also be understood that the term "and / or" used in the specification of the present application and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0031] The following will describe in detail some embodiments of the present application with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0032] Please refer to Figure 1 , Figure 1 which is a schematic diagram of a module of a voltage control device provided by an embodiment of the present application. As shown in Figure 1 , the voltage control device includes an operational amplifier 10, a feedback unit 20, and a DC-DC unit 30;

[0033] The first input terminal of the operational amplifier 10 is used to receive a control signal sent by the control unit 100, and the operational amplifier 10 is used to receive the control signal; the output terminal of the operational amplifier 10 is connected to the second input terminal of the operational amplifier 10 through the feedback unit 20; for the DC-DC unit 30, both the feedback unit 20 and the output terminal of the operational amplifier 10 are connected to the feedback terminal of the DC-DC unit 30.

[0034] Among them, the feedback unit 20 is used to collect the feedback voltage at the feedback terminal of the DC-DC unit 30 and send the feedback voltage to the second input terminal of the operational amplifier 10; the operational amplifier 10 is used to output an adjustment signal to the feedback terminal of the DC-DC unit 30 according to the feedback voltage and the control signal to adjust the feedback voltage at the feedback terminal; the DC-DC unit 30 is used to adjust the output voltage at the output terminal according to the feedback voltage at the feedback terminal so that the feedback voltage at the feedback terminal is restored to the reference voltage.

[0035] Among them, the control unit can be an external device. The control unit is used to send a control signal to the operational amplifier. The control signal can be a signal for controlling the feedback voltage at the feedback terminal of the DC-DC unit. Exemplarily, the control signal can be a DC voltage signal.

[0036] The operational amplifier performs an operation based on the control signal at the first input terminal and the feedback voltage at the feedback terminal of the DC-DC unit returned to the second input terminal, and outputs an adjustment signal to the feedback terminal of the DC-DC unit to change the feedback voltage at the feedback terminal of the DC-DC unit.

[0037] The DC-DC unit is a device or circuit for converting a DC voltage to a DC voltage. Exemplarily, the DC-DC unit can be a DC-DC power chip. The DC-DC unit mainly compares the feedback voltage at the feedback terminal with the internal reference voltage. If the feedback voltage is different from the reference voltage, the DC-DC unit will adjust the output voltage at its output terminal.

[0038] Therefore, according to the characteristics of the DC-DC unit, the feedback voltage at the feedback terminal of the DC-DC unit must be stabilized at a preset reference voltage. Therefore, after the feedback voltage at the feedback terminal of the DC-DC unit changes, the DC-DC unit will adjust the output voltage at its output terminal. According to the internal adjustment mechanism of the DC-DC unit, as the output voltage at the output terminal of the DC-DC unit changes, the feedback voltage at the feedback terminal of the DC-DC unit will gradually return to the preset reference voltage. During the adjustment process, the feedback voltage at the feedback terminal of the DC-DC unit is a continuously changing value. It is not until the output voltage at the output terminal of the DC-DC unit is adjusted to a certain voltage value that the feedback voltage of the DC-DC unit will be stabilized to a fixed value, that is, the internally preset reference voltage of the DC-DC unit.

[0039] By introducing the feedback voltage as feedback, the operational amplifier generates a control signal according to the feedback voltage and the control signal, which can make the feedback voltage at the feedback terminal of the DC-DC unit change based on the feedback voltage at the previous moment. Correspondingly, the output voltage of the DC-DC unit will also change based on the output voltage at the previous moment, and will not cause a large change, and can output a linearly changing voltage.

[0040] In one embodiment, the first input terminal of the operational amplifier may be the inverting input terminal, and the second input terminal may be the non-inverting input terminal. The feedback voltage is introduced as positive feedback. The operational amplifier generates a control signal based on the feedback voltage and the control signal, and sends it to the feedback terminal of the DC-DC unit.

[0041] Optionally, the output terminal of the operational amplifier is connected to the inverting input terminal of the operational amplifier.

[0042] Optionally, the control signal may be a continuous signal whose signal parameter changes linearly. The signal parameter may be a parameter that affects the change of the feedback voltage at the feedback terminal of the DC-DC unit. If the control signal is a DC voltage signal, the control signal may be a DC voltage signal whose voltage value linearly changes from the first volt to the second volt. By inputting a continuous signal whose signal parameter changes linearly as the control signal, the linear change of the output voltage of the DC-DC unit can be controlled from the input side, and the smoothness of the linear change of the output voltage can be increased.

[0043] In one embodiment, the control signal is a pulse width modulation signal. As Figure 2 shown, the voltage control device further includes a signal receiving interface P1, a first capacitor C1, and a first resistor R1. The signal receiving interface P1 is connected to the first input terminal of the operational amplifier 10 through the first resistor R1. The signal receiving interface P1 is also grounded through the first capacitor C1. The signal receiving interface P1 is used to receive the control signal sent by the control unit.

[0044] Among them, the control signal may be a pulse width modulation signal with the same amplitude and different duty cycles. The first capacitor and the first resistor form an RC filter. The signal receiving interface serves as the interface of the voltage control device for receiving the control signal. After being processed by the first capacitor and the first resistor, the control signal will become a DC voltage signal.

[0045] Optionally, the control signal may also be a pulse width modulation signal whose duty cycle changes linearly. By sending a pulse width modulation signal with the same amplitude and different duty cycles, and then converting the pulse width modulation signal to a DC voltage signal through the RC filter, the output voltage of the DC-DC unit can be controlled.

[0046] Figure 3This is the circuit diagram of another voltage control device provided by the embodiments of the present application. In one embodiment, the feedback unit includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a second capacitor C2. One end of the second resistor R2 and one end of the third resistor R3 are both connected to the second input terminal of the operational amplifier 10. The other end of the third resistor R3 and one end of the fifth resistor R5 are both connected to one end of the second capacitor C2. The other end of the fifth resistor R5, the other end of the second capacitor C2, and one end of the fourth resistor R4 are all connected to the output terminal of the operational amplifier 10. The other end of the second resistor R2 and the other end of the fourth resistor R4 are both grounded.

[0047] In one embodiment, the voltage control device further includes a first diode D1 and a sixth resistor R6. The output terminal of the operational amplifier is connected to the positive electrode of the first diode D1, and the negative electrode of the first diode D1 is connected to the feedback terminal FB of the DC-DC unit 30 through the sixth resistor R6.

[0048] Correspondingly, the other end of the fifth resistor of the feedback unit, the other end of the second capacitor, one end of the fourth resistor, and the other end of the sixth resistor are all connected to the feedback terminal FB of the DC-DC unit 30. The other end of the second resistor R2 and the other end of the fourth resistor R4 are both grounded.

[0049] Among them, by setting the first diode and the sixth resistor, the adjustment signal output by the operational amplifier 10 can be unidirectionally transmitted to the feedback terminal of the DC-DC unit.

[0050] In one embodiment, the voltage control device further includes a third capacitor C3. The power supply terminal Vin of the DC-DC unit 30 and one end of the third capacitor C3 are both connected to the power supply. The other end of the third capacitor C3 is grounded. The power supply can be a DC power supply.

[0051] The DC-DC unit can be an asynchronous DC-DC unit or a synchronous DC-DC unit. Specifically, the asynchronous DC-DC unit or the synchronous DC-DC unit can be selected according to the actual requirements.

[0052] In one embodiment, as Figure 4 shown, the DC-DC unit is an asynchronous DC-DC unit. The voltage control device further includes an output interface P2, a first inductor L1, a second diode D2, and a fourth capacitor C4. The output terminal Vout of the DC-DC unit 30 and the negative electrode of the second diode D2 are both connected to one end of the first inductor L1. The other end of the first inductor L1 and one end of the fourth capacitor C4 are both connected to the output interface P2. The positive electrode of the second diode D2 and the other end of the fourth capacitor C4 are grounded. The output interface P2 is used to output the output voltage of the DC-DC unit 30.

[0053] In one embodiment, asFigure 5 As shown, the DC-DC unit is a synchronous DC-DC unit. The voltage control device further includes an output interface P2, a first inductor L1, and a fourth capacitor C4. The output end of the DC-DC unit 30 is connected to one end of the first inductor L1. The other end of the first inductor L1 and one end of the fourth capacitor C4 are both connected to the output interface P2. The other end of the fourth capacitor C4 is grounded. The output interface P2 is used to output the output voltage of the DC-DC unit.

[0054] Among them, the first inductor can be a storage inductor. The output interface can be connected to an external load so that the output voltage of the DC-DC unit can be sent to the external load through the output interface. Exemplarily, the load can be a motor. By sending a linearly varying output voltage to the motor, the rotational speed of the motor can change linearly.

[0055] The embodiment of the present application further provides a voltage control system, as Figure 1 shown. The voltage control system includes a control unit 100 and a voltage control device. The control unit is connected to the voltage control device. The control unit is used to generate a control signal and send it to the voltage control device.

[0056] The voltage control device includes an operational amplifier 10, a feedback unit 20, and a DC-DC unit 30. The first input end of the operational amplifier 10 is used to receive the control signal sent by the control unit 100. The operational amplifier 10 is used to receive the control signal. The output end of the operational amplifier 10 is connected to the second input end of the operational amplifier 10 through the feedback unit 20. For the DC-DC unit 30, the feedback unit 20 and the output end of the operational amplifier 10 are both connected to the feedback end of the DC-DC unit 30.

[0057] Among them, the feedback unit 20 is used to collect the feedback voltage at the feedback end of the DC-DC unit 30 and send the feedback voltage to the second input end of the operational amplifier 10. The operational amplifier 10 is used to output an adjustment signal to the feedback end of the DC-DC unit 30 according to the feedback voltage and the control signal to adjust the feedback voltage at the feedback end. The DC-DC unit 30 is used to adjust the output voltage at the output end according to the feedback voltage at the feedback end so that the feedback voltage at the feedback end is restored to the reference voltage.

[0058] Among them, the control unit can be an external device. The control unit is used to send a control signal to the operational amplifier. The control signal can be a signal for controlling the feedback voltage at the feedback end of the DC-DC unit. Exemplarily, the control signal can be a DC voltage signal.

[0059] The operational amplifier performs operations based on the control signal at the first input terminal and the feedback voltage returned to the feedback terminal of the DC-DC unit at the second input terminal, and outputs an adjustment signal to the feedback terminal of the DC-DC unit to change the feedback voltage at the feedback terminal of the DC-DC unit.

[0060] The DC-DC unit is a device or circuit for converting a DC voltage to a DC voltage. Exemplarily, the DC-DC unit can be a DC-DC power chip. The DC-DC unit mainly compares the feedback voltage at the feedback terminal with the internal reference voltage. If the feedback voltage is not the same as the reference voltage, the DC-DC unit will adjust the output voltage at its output terminal.

[0061] Therefore, according to the characteristics of the DC-DC unit, the feedback voltage at the feedback terminal of the DC-DC unit must be stabilized at a preset reference voltage. So after the feedback voltage at the feedback terminal of the DC-DC unit changes, the DC-DC unit will adjust the output voltage at its output terminal. According to the internal adjustment mechanism of the DC-DC unit, as the output voltage at the output terminal of the DC-DC unit changes, the feedback voltage at the feedback terminal of the DC-DC unit will gradually return to the preset reference voltage. During the adjustment process, the feedback voltage at the feedback terminal of the DC-DC unit is a continuously changing value until the output voltage at the output terminal of the DC-DC unit is adjusted to a certain voltage value, and the feedback voltage of the DC-DC unit will be stabilized at a fixed value, that is, the internal preset reference voltage of the DC-DC unit.

[0062] By introducing the feedback voltage as feedback, the operational amplifier generates a control signal based on the feedback voltage and the control signal, which can make the feedback voltage at the feedback terminal of the DC-DC unit change according to the feedback voltage at the previous moment. Correspondingly, the output voltage of the DC-DC unit will also change according to the output voltage at the previous moment, and will not cause a large change, and can output a linearly changing voltage.

[0063] In one embodiment, the first input terminal of the operational amplifier can be the inverting input terminal, and the second input terminal can be the non-inverting input terminal. The feedback voltage is introduced as positive feedback. The operational amplifier generates a control signal based on the feedback voltage and the control signal and sends it to the feedback terminal of the DC-DC unit.

[0064] Optionally, the output terminal of the operational amplifier is connected to the inverting input terminal of the operational amplifier.

[0065] In one embodiment, the control unit is configured to generate pulse width modulation signals with the same amplitude and different duty cycles. The voltage control device further includes a signal receiving interface P1, a first capacitor C1, and a first resistor R1. The signal receiving interface P1 is connected to the first input terminal of the operational amplifier 10 through the first resistor R1. The signal receiving interface P1 is also grounded through the first capacitor C1. The signal receiving interface P1 is used to receive the control signal sent by the control unit. The first capacitor and the first resistor form an RC filter. The signal receiving interface serves as the interface of the voltage control device for receiving the control signal. After being processed by the first capacitor and the first resistor, the control signal will become a DC voltage signal.

[0066] Optionally, the control signal can also be a pulse width modulation signal with a linearly varying duty cycle. By sending pulse width modulation signals with the same amplitude and different duty cycles, and then converting the pulse width modulation signals to DC voltage signals through the RC filter, the output voltage of the DC-DC unit can be controlled.

[0067] Figure 3 The following is a circuit diagram of another voltage control device provided by an embodiment of the present application. In one embodiment, the feedback unit includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a second capacitor C2. One end of the second resistor R2 and one end of the third resistor R3 are both connected to the second input terminal of the operational amplifier 10. The other end of the third resistor R3 and one end of the fifth resistor R5 are both connected to one end of the second capacitor C2. The other end of the fifth resistor R5, the other end of the second capacitor C2, and one end of the fourth resistor R4 are all connected to the output terminal of the operational amplifier 10. The other end of the second resistor R2 and the other end of the fourth resistor R4 are both grounded.

[0068] In one embodiment, the voltage control device further includes a first diode D1 and a sixth resistor R6. The output terminal of the operational amplifier is connected to the positive electrode of the first diode D1. The negative electrode of the first diode D1 is connected to the feedback terminal FB of the DC-DC unit 30 through the sixth resistor R6.

[0069] Correspondingly, the other end of the fifth resistor of the feedback unit, the other end of the second capacitor, one end of the fourth resistor, and the other end of the sixth resistor are all connected to the feedback terminal FB of the DC-DC unit 30. The other end of the second resistor R2 and the other end of the fourth resistor R4 are both grounded.

[0070] Among them, by setting the first diode and the sixth resistor, the adjustment signal output by the operational amplifier 10 can be unidirectionally transmitted to the feedback terminal of the DC-DC unit.

[0071] In one embodiment, the voltage control device further includes a third capacitor C3. One end of the power supply terminal Vin of the DC-DC unit 30 and one end of the third capacitor C3 are both connected to the power supply, and the other end of the third capacitor C3 is grounded. The power supply can be a DC power supply.

[0072] The DC-DC unit can be an asynchronous DC-DC unit or a synchronous DC-DC unit. Specifically, the asynchronous DC-DC unit or the synchronous DC-DC unit can be selected according to the requirements of the actual situation.

[0073] In one embodiment, as Figure 4 shown, the DC-DC unit is an asynchronous DC-DC unit. The voltage control device further includes an output interface P2, a first inductor L1, a second diode D2, and a fourth capacitor C4. The output terminal Vout of the DC-DC unit 30 and the cathode of the second diode D2 are both connected to one end of the first inductor L1. The other end of the first inductor L1 and one end of the fourth capacitor C4 are both connected to the output interface P2. The anode of the second diode D2 and the other end of the fourth capacitor C4 are grounded. The output interface P2 is used to output the output voltage of the DC-DC unit 30.

[0074] In one embodiment, as Figure 5 shown, the DC-DC unit is a synchronous DC-DC unit. The voltage control device further includes an output interface P2, a first inductor L1, and a fourth capacitor C4. The output terminal of the DC-DC unit 30 is connected to one end of the first inductor L1. The other end of the first inductor L1 and one end of the fourth capacitor C4 are both connected to the output interface P2. The other end of the fourth capacitor C4 is grounded. The output interface P2 is used to output the output voltage of the DC-DC unit.

[0075] Among them, the first inductor can be a storage inductor. The output interface can be connected to an external load so that the output voltage of the DC-DC unit can be sent to the external load through the output interface. Exemplarily, the load can be a motor. By sending a linearly varying output voltage to the motor, the rotational speed of the motor can change linearly.

[0076] As described above, the above is only the specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A voltage control device, characterized in that, it includes: an operational amplifier, the first input terminal of the operational amplifier is used to receive a control signal sent by a control unit, and the control signal is a continuous signal whose signal parameters change linearly; a feedback unit, the input terminal of the feedback unit is connected to the output terminal of the operational amplifier, and the output terminal of the feedback unit is connected to the second input terminal of the operational amplifier; a DC-DC unit, the feedback terminal of the DC-DC unit is connected to the feedback unit and the output terminal of the operational amplifier; wherein, the feedback unit is used to collect the feedback voltage at the feedback terminal of the DC-DC unit and send the feedback voltage to the second input terminal of the operational amplifier; the operational amplifier takes the feedback voltage sent from the output terminal of the feedback unit to the second input terminal of the operational amplifier as feedback; the operational amplifier is used to output an adjustment signal to the feedback terminal of the DC-DC unit according to the feedback voltage and the control signal to adjust the feedback voltage at the feedback terminal; the DC-DC unit is used to adjust the output voltage at the output terminal according to the feedback voltage at the feedback terminal, the feedback voltage changes continuously based on the feedback voltage at the previous moment, and the output voltage changes linearly based on the output voltage at the previous moment, so that the feedback voltage at the feedback terminal is restored to the reference voltage.

2. The voltage control device according to claim 1, characterized in that, the control signal is a pulse width modulation signal, and the voltage control device further includes a signal receiving interface, a first capacitor and a first resistor. The signal receiving interface is connected to the first input terminal of the operational amplifier through the first resistor, and the signal receiving interface is also grounded through the first capacitor. The signal receiving interface is used to receive the control signal sent by the control unit.

3. The voltage control device according to claim 1, characterized in that, the feedback unit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor and a second capacitor. One end of the second resistor and one end of the third resistor are both connected to the second input terminal of the operational amplifier. The other end of the third resistor and one end of the fifth resistor are both connected to one end of the second capacitor. The other end of the fifth resistor, the other end of the second capacitor and one end of the fourth resistor are all connected to the output terminal of the operational amplifier. The other end of the second resistor and the other end of the fourth resistor are both grounded.

4. The voltage control device according to any one of claims 1 to 3, characterized in that, the first input terminal is an inverting input terminal, and the second input terminal is a non-inverting input terminal.

5. The voltage control device according to claim 1, characterized in that, the voltage control device further includes a first diode and a sixth resistor. The output terminal of the operational amplifier is connected to the positive electrode of the first diode, and the negative electrode of the first diode is connected to the feedback terminal of the DC-DC unit through the sixth resistor.

6. The voltage control device according to claim 1, characterized in that, The voltage control device further includes a third capacitor. One end of the power supply terminal of the DC-DC unit and one end of the third capacitor are both connected to a power supply, and the other end of the third capacitor is grounded.

7. The voltage control device according to claim 1, wherein, the DC-DC unit is a non-synchronous DC-DC unit, and the voltage control device further includes an output interface, a first inductor, a second diode, and a fourth capacitor. The output terminal of the DC-DC unit and the cathode of the second diode are both connected to one end of the first inductor. The other end of the first inductor and one end of the fourth capacitor are both connected to the output interface. The anode of the second diode and the other end of the fourth capacitor are grounded. The output interface is used to output the output voltage of the DC-DC unit.

8. The voltage control device according to claim 1, wherein, the DC-DC unit is a synchronous DC-DC unit, and the voltage control device further includes an output interface, a first inductor, and a fourth capacitor. The output terminal of the DC-DC unit is connected to one end of the first inductor. The other end of the first inductor and one end of the fourth capacitor are both connected to the output interface. The other end of the fourth capacitor is grounded. The output interface is used to output the output voltage of the DC-DC unit.

9. A voltage control system, wherein, the voltage control system includes a control unit and the voltage control device according to any one of claims 1 to 8; the control unit is connected to the voltage control device, and the control unit is configured to generate a control signal and send it to the voltage control device.

10. The voltage control system according to claim 9, wherein, the control unit is configured to generate pulse width modulation signals with the same amplitude and different duty cycles.

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