ZVSBUCK circuit based on single-chip microcomputer control and working method thereof

Abstract

The invention discloses a ZVSBUCK circuit based on single-chip microcomputer control and a working method thereof. The circuit comprises a single-chip microcomputer control circuit, a ZVS switch topology circuit, a BUCK circuit main body part and an auxiliary circuit. The single-chip microcomputer control circuit is used for receiving an input signal and outputting a PWM control signal after processing the input signal. The ZVS switch topology circuit is used for realizing zero-voltage turn-on and turn-off of a switching device in the ZVS switch topology circuit based on the PWM control signal; the BUCK circuit main body part is used for realizing DC-DC voltage conversion; the auxiliary circuit is used for providing power and signal conditions for the circuit and protecting operation of the circuit. The circuit is simple in structure and good in cost control, circuit accurate control and zero-voltage on and off of a switching device are achieved, switching loss and the miller charge effect are effectively eliminated, circuit efficiency is improved, and high power density and excellent dynamic response performance of a power supply system are kept.

Description

Technical Field

[0001] The invention belongs to the technical field of power electronic auxiliary circuits, and in particular relates to a ZVSBUCK circuit based on single chip microcomputer control and a working method thereof. Background Art

[0002] At present, the efficiency and power density of traditional buck regulators are often limited by switching losses when dealing with high input voltage and high power loads. These losses mainly come from the conduction loss of the high-level MOSFET, the Miller gate charge, and the conduction loss of the body diode. In particular, as the input voltage increases, these losses will be further amplified, seriously affecting the overall performance of the regulator. In addition, the switching frequency of traditional regulators is also limited by switching losses and cannot be further increased. The increase in switching frequency means that the switching time of MOSFET is longer and the loss is greater, which in turn limits the use of smaller power components and affects the power density of the regulator. With the rapid development of power electronics technology, especially the widespread application of single-chip microcomputers and digital signal processors, higher requirements are put forward for circuit board design. Realizing high power density and high efficiency regulators in limited space has become a key challenge in the industry. Traditional high-density regulators are limited by switching losses and it is difficult to maintain high efficiency at high input voltage and high switching frequency, which limits their application in modern electronic devices.

[0003] As the requirements for power systems become increasingly stringent, especially in the pursuit of high power density, high efficiency and miniaturization, the traditional hard-switching Buck circuit can no longer meet the requirements. Hard-switching circuits will generate large switching losses during the switching process, including conduction losses of high-level MOSFETs, Miller effect, and conduction losses of body diodes. These losses not only reduce the overall efficiency, but also limit the increase in switching frequency, thereby affecting the power density and dynamic response capabilities of the circuit.

[0004] As an improvement, in order to reduce losses, researchers have tried to optimize device selection, improve drive circuits, etc., but the results are limited. ZVS technology can achieve zero voltage turn-on and turn-off of switching devices to a certain extent through resonance, eliminating switching losses and Miller charge effect, and improving circuit efficiency. However, the current ZVS circuit, due to the need to eliminate switching losses and Miller charge effect and improve circuit efficiency, has a relatively complex circuit structure and high cost, and is difficult to integrate with control units such as microcontrollers. Summary of the invention

[0005] The present invention provides a ZVSBUCK circuit based on single-chip microcomputer control and a working method thereof, aiming to solve the problem that the current ZVS circuit has a relatively complex circuit structure and a high cost due to the need to eliminate switching loss and Miller charge effect and improve circuit efficiency, and is difficult to integrate with control units such as single-chip microcomputers.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: The present invention provides a ZVSBUCK circuit based on single-chip microcomputer control, the ZVSBUCK circuit comprises a single-chip microcomputer control circuit, a ZVS switch topology circuit, a BUCK circuit main part and an auxiliary circuit, the single-chip microcomputer control circuit acts on a switch device in the ZVS switch topology circuit through a driving circuit to realize DC-DC voltage conversion; wherein: The single-chip microcomputer control circuit is used to receive input signals, and output PWM control signals to the ZVS switch topology circuit after signal processing, so as to drive the ZVS switch topology circuit to work; the ZVS switch topology circuit is used to receive the PWM control signal output by the single-chip microcomputer control circuit, and realize zero-voltage conduction and shutdown of the switching devices in the ZVS switch topology circuit through resonance, so as to eliminate switching losses and Miller charge effects; the main part of the BUCK circuit is used to realize DC-DC voltage conversion; the auxiliary circuit is used to provide power and signal conditions for the single-chip microcomputer control circuit and the ZVS switch topology circuit, and protect the operation of the circuit by means of overvoltage protection and short-circuit protection.

[0007] In some implementations, the single-chip control circuit has an input voltage monitoring module and an output voltage monitoring module, and calculates a preset duty cycle in real time through a built-in algorithm to generate a corresponding PWM control signal.

[0008] In some embodiments, the ZVS switch topology circuit includes a power supply Vin, a high-side MOSFET Q1, a synchronous MOSFET Q2, a clamp switch QZVS, an output voltage Vout, a voltage reference source Vs, an output inductor L1, and an output capacitor; Vin is connected to the input end of the high-side MOSFET Q1, and the drain and source of the high-side MOSFET Q1 and the synchronous MOSFET Q2 are connected through L1 and the output capacitor to form a path; one end of QZVS is connected to a node between the high-side MOSFET Q1 and the synchronous MOSFET Q2, and the other end is connected to Vout.

[0009] Furthermore, the ZVS switch topology circuit also includes PWMZVS, the output end of PWMZVS is connected to the gates of the high-side MOSFETQ1 and the synchronous MOSFETQ2, and PWMZVS is used to protect the operation of the circuit by means of overvoltage protection and short circuit protection.

[0010] Furthermore, an output capacitor is connected to the source of the high-side MOSFET Q1 and the synchronous MOSFET Q2 for stabilizing the output voltage.

[0011] Furthermore, the clamping switch QZVS is used to close or open at a specific time to clamp the voltage VS to Vout, thereby providing conditions for zero voltage switching in the next switching cycle.

[0012] Furthermore, the high-side MOSFET Q1 and the synchronous MOSFET Q2 are used to be alternately turned on and off under the driving of the PWM control signal, thereby controlling the flow of current in the inductor L1 to achieve zero voltage switching.

[0013] Furthermore, the ZVS switch topology circuit further includes a Hall effect sensor HO, which is used to feed back the monitored current signal to the PWMZVS or other control circuits for adjusting the control signal and realizing circuit protection.

[0014] In some implementations, the ZVSBUCK circuit uses a digital chip to control an auxiliary soft-switch MOS tube, and the auxiliary circuit includes a driver, which is used to enhance the driving capability of the PWM control signal, thereby driving the MOS tube.

[0015] The present invention also provides a working method of a ZVSBUCK circuit based on single chip microcomputer control, comprising the following steps: The single-chip microcomputer control circuit receives the input signal and calculates the preset duty cycle in real time to generate a PWM control signal; the single-chip microcomputer control circuit outputs the PWM control signal to the ZVS switch topology circuit to achieve zero voltage switching; The ZVS switch topology circuit receives the PWM control signal and realizes zero voltage turn-on and turn-off of the switch device through resonance. At the same time, the clamp switch is closed or opened at a specific time to provide conditions for zero voltage switching in the next switching cycle. The main part of the BUCK circuit realizes DC-DC voltage conversion, and the auxiliary circuit provides power and signal conditions for the microcontroller control circuit and the ZVS switch topology circuit. At the same time, overvoltage protection and short-circuit protection are used to protect the operation of the circuit.

[0016] Compared with the prior art, the ZVSBUCK circuit based on single chip microcomputer control and the working method thereof of the present invention have the following beneficial effects: The present invention discloses a ZVSBUCK circuit based on single-chip microcomputer control. The ZVSBUCK circuit includes a single-chip microcomputer control circuit, a ZVS switch topology circuit, a BUCK circuit main part, and an auxiliary circuit. The single-chip microcomputer control circuit acts on a switch device in the ZVS switch topology circuit through a driving circuit to realize DC-DC voltage conversion; wherein: the single-chip microcomputer control circuit is used to receive an input signal, and output a PWM control signal to the ZVS switch topology circuit after signal processing, driving the ZVS switch topology circuit to work; the ZVS switch topology circuit is used to receive the PWM control signal output by the single-chip microcomputer control circuit, and realize zero-voltage conduction and shutdown of the switch device in the ZVS switch topology circuit through resonance, so as to eliminate switching loss and Miller charge effect; the BUCK circuit main part is used to realize DC-DC voltage conversion; the auxiliary circuit is used to provide power and signal conditions for the single-chip microcomputer control circuit and the ZVS switch topology circuit, and protect the operation of the circuit by overvoltage protection and short-circuit protection. Based on the above, the ZVSBUCK circuit of the present invention has a simple structure, better cost control, and better integration. The circuit realizes precise control through a single-chip microcomputer control circuit, and realizes zero-voltage turn-on and turn-off of the switch device by using a ZVS switch topology circuit, effectively eliminating switching losses and Miller charge effect, and improving circuit efficiency and stability. The main part of the BUCK circuit realizes DC-DC voltage conversion to meet different voltage requirements. The auxiliary circuit provides the necessary power supply and signal conditions for the entire circuit, and can ensure the safe operation of the circuit based on overvoltage protection and short-circuit protection. The circuit of the present invention realizes efficient operation at higher frequencies and higher input voltages by adopting a zero-voltage topology, and avoids high-current body diode conduction before the high-end MOSFET is turned on, so that the drain-source voltage of the high-end MOSFET is zero or close to zero. It is of great significance for the high-efficiency and low-ripple characteristics of the BUCK conversion, while maintaining the high power density and excellent dynamic response performance of the power supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0018] Figure 1 A schematic diagram of a ZVSBUCK circuit in a single chip microcomputer controlled ZVSBUCK circuit and a working method thereof according to the present invention; Figure 2 It is a schematic diagram of a single-chip microcomputer control circuit 1 in a ZVSBUCK circuit based on single-chip microcomputer control and a working method thereof of the present invention; Figure 3 It is a schematic diagram of a single-chip microcomputer control circuit 2 in a ZVSBUCK circuit based on single-chip microcomputer control and a working method thereof of the present invention; Figure 4 A schematic diagram of a ZVS switch topology circuit in a ZVSBUCK circuit based on single-chip microcomputer control and a working method thereof according to the present invention; Figure 5 The present invention is a schematic diagram of a ZVSBUCK circuit based on single chip microcomputer control and an auxiliary circuit in a working method thereof. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0022] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0023] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] How to provide an overall architecture of a BUCK soft switching circuit based on microcontroller control drive, thereby improving the high switching loss, high current spike pulse and ringing problems of the traditional BUCK circuit.

[0026] Based on this, Figure 1-3 As shown, the present invention is a ZVSBUCK circuit based on single-chip microcomputer control, the ZVSBUCK circuit includes a single-chip microcomputer control circuit, a ZVS switch topology circuit, a BUCK circuit main part and an auxiliary circuit, the single-chip microcomputer control circuit acts on the switch device in the ZVS switch topology circuit through a driving circuit to realize DC-DC voltage conversion; wherein: The single-chip microcomputer control circuit is used to receive input signals, and output PWM control signals to the ZVS switch topology circuit after signal processing, so as to drive the ZVS switch topology circuit to work; the ZVS switch topology circuit is used to receive the PWM control signal output by the single-chip microcomputer control circuit, and realize zero-voltage conduction and shutdown of the switching devices in the ZVS switch topology circuit through resonance, so as to eliminate switching losses and Miller charge effects; the main part of the BUCK circuit is used to realize DC-DC voltage conversion; the auxiliary circuit is used to provide power and signal conditions for the single-chip microcomputer control circuit and the ZVS switch topology circuit, and protect the operation of the circuit by means of overvoltage protection and short-circuit protection.

[0027] In the ZVSBUCK circuit based on single-chip microcomputer control of the present invention, a high-power density and high-efficiency DC-DC voltage conversion is achieved by integrating a BUCK circuit with a high-performance ZVS switch topology and driving through single-chip microcomputer control. The present invention eliminates switching losses and Maitreya charge effect by adopting the ZVS switch topology, significantly improving the power density and efficiency of the circuit. The present invention proposes to use a digital chip to control an auxiliary soft-switching MOS tube, and the digital control unit can adjust the control signal in real time, thereby achieving precise control of the circuit and enhancing the stability of the system. Compared with the currently available BUCK soft-switching circuit, soft switching within the full input voltage range can be achieved. At the same time, due to the use of smaller passive components and an efficient ZVS switch topology, the circuit does not require an additional series resonant circuit, making the circuit design relatively simple, and can effectively reduce the cost of the product, while saving space occupancy and improving the power conversion efficiency and ripple parameters.

[0028] In some embodiments, in the ZVSBUCK circuit of the present invention, the single-chip control circuit has a module for monitoring input voltage and a module for monitoring output voltage, and calculates the preset duty cycle in real time through a built-in algorithm to generate a corresponding PWM control signal. The single-chip control circuit of the present invention has the function of monitoring input voltage and output voltage, and can calculate the preset duty cycle in real time and generate a corresponding PWM control signal. This enables the circuit to be dynamically adjusted according to changes in input voltage and output voltage.

[0029] In some embodiments, the ZVS switch topology circuit of the present invention includes a power supply Vin, a high-end MOSFETQ1, a synchronous MOSFETQ2, a clamp switch QZVS, an output voltage Vout, a voltage reference source Vs, an output inductor L1, and an output capacitor; Vin is connected to the input end of the high-end MOSFETQ1, and the drain and source of the high-end MOSFETQ1 and the synchronous MOSFETQ2 are connected through L1 and the output capacitor to form a path; one end of QZVS is connected to the node between the high-end MOSFETQ1 and the synchronous MOSFETQ2, and the other end is connected to Vout.

[0030] Furthermore, the ZVS switch topology circuit of the present invention also includes PWMZVS, the output end of PWMZVS is connected to the gate of the high-end MOSFETQ1 and the synchronous MOSFETQ2, and PWMZVS protects the operation of the circuit by overvoltage protection and short-circuit protection. The output capacitor is connected to the source of the high-end MOSFETQ1 and the synchronous MOSFETQ2 to stabilize the output voltage. The clamping switch QZVS is used to close or open at a specific time to clamp the voltage VS to Vout, providing conditions for the zero voltage switch of the next switching cycle. The high-end MOSFETQ1 and the synchronous MOSFETQ2 are used to alternately turn on and off under the drive of the PWM control signal, thereby controlling the flow of current in the inductor L1 to achieve zero voltage switching. The PWMZVS of the present invention enhances the anti-interference ability and safety of the circuit. The output capacitor is connected to the source of the high-end MOSFETQ1 and the synchronous MOSFETQ2 to stabilize the output voltage and reduce the fluctuation of the output voltage. The clamping switch QZVS is closed or opened at a specific time to clamp the voltage VS to Vout, providing conditions for the zero voltage switch of the next switching cycle. Continuous zero voltage switching operation is achieved, switching losses are reduced and circuit efficiency is improved. High-side MOSFET Q1 and synchronous MOSFET Q2 are used to alternately turn on and off under the drive of PWM control signals, thereby controlling the flow of current in the inductor, achieving effective control of the circuit current and helping to achieve stable DC-DC voltage conversion.

[0031] In some embodiments, the ZVSBUCK circuit of the present invention uses a digital chip to control an auxiliary soft switch MOS tube, and the auxiliary circuit includes a driver, which is used to enhance the driving capability of the PWM control signal, thereby driving the MOS tube. The digital control unit can adjust the control signal in real time, realize the precise control of the circuit, and enhance the stability of the circuit.

[0032] like Figure 1 and Figure 2 As shown, the parameters of the resistors and capacitors around the microcontroller can be set with reference to the specific microcontroller when designing, and the parameters can be referenced when necessary. Microcontroller 1 receives the external feedback signal, and directly outputs the high-side drive logic level signal of the BUCK circuit to driver 1 (auxiliary driver 1) after internal calculation, and drives the high-side switch tube of the BUCK power supply after amplification by the isolation driver. After calculation, the current sampling signal is connected to microcontroller 2, and after processing, the drive logic level of the BUCK freewheeling tube and the clamping MOS tube is output, and then amplified by the isolation driver (auxiliary driver 2) to drive the BUCK freewheeling tube and the clamping tube.

[0033] The present invention also provides a working method of a ZVSBUCK circuit based on single chip microcomputer control, comprising the following steps: The single-chip microcomputer control circuit receives the input signal and calculates the preset duty cycle in real time to generate a PWM control signal; the single-chip microcomputer control circuit outputs the PWM control signal to the ZVS switch topology circuit to achieve zero voltage switching; The ZVS switch topology circuit receives the PWM control signal and realizes zero voltage turn-on and turn-off of the switch device through resonance. At the same time, the clamp switch is closed or opened at a specific time to provide conditions for zero voltage switching in the next switching cycle. The main part of the BUCK circuit realizes DC-DC voltage conversion, and the auxiliary circuit provides power and signal conditions for the microcontroller control circuit and the ZVS switch topology circuit. At the same time, overvoltage protection and short-circuit protection are used to protect the operation of the circuit.

[0034] In the method of the present invention, technical guidance is provided for the operation in the circuit operation through signal reception and processing of the single-chip control circuit, output and driving of the PWM control signal, operation of the ZVS switch topology circuit and DC-DC voltage conversion of the main part of the BUCK circuit, and the method has certain practicality.

[0035] The following is a detailed description of a ZVSBUCK circuit based on single chip microcomputer control and a working method thereof according to the present invention through specific embodiments.

[0036] The ZVSBUCK circuit based on single-chip microcomputer control of the present invention mainly consists of a single-chip microcomputer control circuit, a high-performance ZVS switch topology circuit, a BUCK circuit main body (including input and output capacitors, inductors, etc.) and necessary auxiliary circuits.

[0037] like Figure 2 and Figure 3 As shown, the microcontroller control circuit is responsible for receiving the input signal, outputting the control signal after processing through the internal algorithm, and driving the ZVS switch topology to work.

[0038] Specifically, the single-chip control circuit of the present invention is responsible for monitoring the input voltage and the output voltage, calculating the required duty cycle in real time through a built-in algorithm, and generating a corresponding PWM control signal. The control signal acts accurately on the high-end MOSFET Q1 and the synchronous MOSFET Q2 in the switch topology through the drive circuit, thereby achieving zero-voltage turn-on and turn-off of Q1 and Q2.

[0039] like Figure 4 As shown, a high-performance ZVS switching topology circuit: This topology uses resonance to eliminate switching losses and Miller charge effect, allowing the circuit to maintain high efficiency operation at high input voltage.

[0040] Specifically, the ZVS switching circuit: at the beginning of the switching cycle, the current flowing through the output inductor L1 is almost zero. At this time, due to the zero voltage switching action, the voltage of Q1 is maintained at an extremely low level, close to zero. As the control signal sent by the microcontroller drives the circuit into operation, the inductor current begins to gradually rise from zero until it reaches the preset peak current. After that, Q1 is turned off at the appropriate time, and the inductor current is quickly transferred to the body diode of Q2. The time of this process is relatively short, less than 10ns. Subsequently, Q2 is turned on under zero voltage conditions and continues to maintain the current path of the circuit. At this time, the energy stored in the inductor is transferred to the load. After that, Q2 is turned off after a delay until the current from the output capacitor drives the inductor current to negative, and the inductor begins to store energy. Then the clamp switch QZVS is closed and turned on until Q1 needs to be turned on again and VS is clamped to Vout. After that, QZVS is open to provide conditions for zero voltage switching. At this time, the stored energy resonates with the output capacitors of Q1 and Q2. The resonant current flows from the source to the drain into Q1 to discharge C1, and flows from the drain to the source into Q2 to charge C2. Since the body diode conduction of Q1 is avoided, the drain-source voltage of Q1 is zero or close to zero, and no high current spikes or destructive ringing will be generated. In general, in this process, the energy stored in the inductor can be circulated through resonance within the ZVS switching topology until the start of the next switching cycle.

[0041] Buck circuit body: The buck circuit body allows the use of smaller passive components such as resistors, inductors and capacitors, thereby increasing the power density of the circuit.

[0042] like Figure 5 As shown, the necessary auxiliary circuit: The auxiliary circuit is the supplementary part of the main circuit, which can provide the required power supply, signal and other conditions for the main circuit, and can also stabilize the normal operation of the entire circuit system based on overvoltage and short circuit protection. The auxiliary circuit has a weak signal driving ability from the microcontroller, and drives the MOS tube after passing through the driver.

[0043] In summary, the ZVSBUCK circuit based on single-chip microcomputer control and its working method of the present invention can simplify the circuit structure and improve energy efficiency. The present invention has certain applicable significance in the field of power supply, can reduce energy consumption and power loss in application, and improves power conversion efficiency and ripple parameters on the basis of simplifying the circuit structure and improving volume saving.

[0044] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician in the industry can smoothly implement the present invention as shown in the specification and described above. However, any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A ZVSBUCK circuit based on single chip microcomputer control, characterized in that: The ZVSBUCK circuit includes a single-chip control circuit, a ZVS switch topology circuit, a BUCK circuit main body and an auxiliary circuit. The single-chip control circuit acts on the switch device in the ZVS switch topology circuit through a drive circuit to achieve DC-DC voltage conversion; wherein: The single-chip microcomputer control circuit is used to receive an input signal, and output a PWM control signal to the ZVS switch topology circuit after signal processing, so as to drive the ZVS switch topology circuit to work; the ZVS switch topology circuit is used to receive the PWM control signal output by the single-chip microcomputer control circuit, and realize zero-voltage conduction and shutdown of the switch device in the ZVS switch topology circuit through resonance, so as to eliminate switching loss and Miller charge effect; the main part of the BUCK circuit is used to realize DC-DC voltage conversion; the auxiliary circuit is used to provide power supply and signal conditions for the single-chip microcomputer control circuit and the ZVS switch topology circuit, and protect the operation of the circuit by overvoltage protection and short-circuit protection.

2. The ZVSBUCK circuit based on single chip microcomputer control according to claim 1, characterized in that: The single chip control circuit has an input voltage monitoring module and an output voltage monitoring module, and calculates a preset duty cycle in real time through a built-in algorithm to generate a corresponding PWM control signal.

3. The ZVSBUCK circuit based on single chip microcomputer control according to claim 1, characterized in that: The ZVS switch topology circuit includes a power supply Vin, a high-end MOSFETQ1, a synchronous MOSFETQ2, a clamp switch QZVS, an output voltage Vout, a voltage reference source Vs, an output inductor L1, and an output capacitor; Vin is connected to the input end of the high-end MOSFETQ1, and the drain and source of the high-end MOSFETQ1 and the synchronous MOSFETQ2 are connected through L1 and the output capacitor to form a path; one end of QZVS is connected to a node between the high-end MOSFETQ1 and the synchronous MOSFETQ2, and the other end is connected to Vout.

4. The ZVSBUCK circuit based on single chip microcomputer control according to claim 3, characterized in that: The ZVS switch topology circuit further includes PWMZVS, the output end of PWMZVS is connected to the gates of the high-end MOSFETQ1 and the synchronous MOSFETQ2, and PWMZVS is used to protect the operation of the circuit by means of overvoltage protection and short circuit protection.

5. The ZVSBUCK circuit based on single chip microcomputer control according to claim 3, characterized in that: The output capacitor is connected to the source of the high-side MOSFET Q1 and the synchronous MOSFET Q2 to stabilize the output voltage.

6. The ZVSBUCK circuit based on single chip microcomputer control according to claim 3, characterized in that: The clamping switch QZVS is used to close or open at a specific time to clamp the voltage VS to Vout, thereby providing conditions for zero voltage switching in the next switching cycle.

7. The ZVSBUCK circuit based on single chip microcomputer control according to claim 3, characterized in that: The high-side MOSFET Q1 and the synchronous MOSFET Q2 are used to be alternately turned on and off under the drive of the PWM control signal, thereby controlling the flow of current in the inductor L1 to achieve zero voltage switching.

8. The ZVSBUCK circuit based on single chip microcomputer control according to claim 4, characterized in that: The ZVS switch topology circuit further includes a Hall effect sensor HO, which is used to feed back a monitored current signal to the PWMZVS or other control circuits for adjusting the control signal and realizing circuit protection.

9. The ZVSBUCK circuit based on single chip microcomputer control according to claim 1, characterized in that: The ZVSBUCK circuit uses a digital chip to control an auxiliary soft-switch MOS tube. The auxiliary circuit includes a driver, which is used to enhance the driving capability of the PWM control signal, thereby driving the MOS tube.

10. The working method of the ZVSBUCK circuit based on single chip microcomputer control according to any one of claims 1 to 9, characterized in that: The steps include: The single-chip microcomputer control circuit receives the input signal and calculates the preset duty cycle in real time to generate a PWM control signal; the single-chip microcomputer control circuit outputs the PWM control signal to the ZVS switch topology circuit to achieve zero voltage switching; The ZVS switch topology circuit receives the PWM control signal and realizes zero voltage turn-on and turn-off of the switch device through resonance. At the same time, the clamp switch is closed or opened at a specific time to provide conditions for zero voltage switching in the next switching cycle. The main part of the BUCK circuit realizes DC-DC voltage conversion, and the auxiliary circuit provides power and signal conditions for the microcontroller control circuit and the ZVS switch topology circuit. At the same time, overvoltage protection and short-circuit protection are used to protect the operation of the circuit.

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