Boost drive circuit

Abstract

The invention relates to a boost driving circuit, and relates to the technical field of voltage conversion. In the boost driving circuit, a first power supply is connected with a driving chip and is used for supplying power to the driving chip; a first switch tube and a second switch tube are integrated in the driving chip, and the driving chip is used for controlling the on and off of the first switch tube and the second switch tube; the second power supply is connected with the primary side push-pull circuit and is used for inputting direct current voltage to the primary side push-pull circuit; one end of the primary side push-pull circuit is connected with the first switch tube, the other end is connected with the second switch tube, and the primary side push-pull circuit is used for converting direct-current voltage into alternating-current voltage and boosting the alternating-current voltage; and the secondary rectification circuit is connected with the primary push-pull circuit and is used for carrying out rectification processing on the boosted AC voltage and outputting a target DC voltage. According to the boost driving circuit, the output voltage range is expanded, the efficiency of the transformer is improved, and the working efficiency of the boost driving circuit is improved while the number of turns of the transformer is reduced, the size of the transformer is reduced and the cost of the transformer is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of voltage conversion, and in particular to a boost driving circuit. Background Art

[0002] A push-pull transformer is a device used in electronic circuits to convert input signals or power from one level to another. It is usually composed of a primary winding and a secondary winding that are coupled to each other. Push-pull transformers are suitable for scenarios that require higher output power and a wider output voltage range. The two primary winding coils are controlled by two switching tubes to alternately conduct, thereby generating a continuous output AC voltage. The output voltage can be adjusted by controlling the turns ratio of the primary winding and the secondary winding.

[0003] In the boost drive circuit based on the push-pull transformer in the related art, an input power supply is used as both the power supply of the driver chip so that the driver chip controls the on and off of the switch tube, and as the input power supply of the transformer, so as to output the target voltage through voltage conversion. However, due to the low voltage of the power supply of the driver chip, if a wider output voltage is to be output, the turns ratio and volume of the transformer will increase, which will increase the transformer cost and transformer efficiency, resulting in low working efficiency of the drive circuit.

[0004] Currently, no effective solution has been proposed for the problems of narrow output voltage range, large number of transformer turns, large size, high transformer cost and low working efficiency of the boost drive circuit in the related art. Summary of the invention

[0005] The boost drive circuit provided by the embodiment of the present invention at least solves the problems of the boost drive circuit in the related art, namely, narrow output voltage range, large number of transformer turns, large volume, high transformer cost and low working efficiency of the drive circuit.

[0006] In order to solve the above problem, one aspect of an embodiment of the present invention provides a boost driving circuit, including: a driving chip, a primary side push-pull circuit, a secondary side rectifier circuit, a first power supply and a second power supply; wherein,

[0007] The first power supply is connected to the driver chip and is used to supply power to the driver chip;

[0008] The driver chip integrates a first switch tube and a second switch tube, and the driver chip is used to control the conduction and disconnection of the first switch tube and the second switch tube;

[0009] The second power supply is connected to the primary push-pull circuit and is used to input a DC voltage to the primary push-pull circuit;

[0010] One end of the primary side push-pull circuit is connected to the first switch tube, and the other end is connected to the second switch tube, and is used to convert the DC voltage into AC voltage and perform voltage boost processing;

[0011] The secondary side rectifier circuit is connected to the primary side push-pull circuit, and is used to rectify the boosted AC voltage and output a target DC voltage.

[0012] In some embodiments, the primary push-pull circuit includes a primary winding, a push-pull transformer and a secondary winding; wherein,

[0013] The primary winding includes a first primary winding coil and a second primary winding coil wound in parallel, the same-name end of the first primary winding coil is connected to the first switch tube in the driving chip, the opposite-name end of the second primary winding coil is connected to the second switch tube in the driving chip, and the second power supply is connected to the center point of the primary winding;

[0014] The secondary winding comprises a first secondary winding coil and a second secondary winding coil which are wound in parallel, and the secondary winding is symmetrically arranged with the primary winding.

[0015] In some embodiments, the secondary side rectifier circuit includes a first rectifier diode and a second rectifier diode; wherein,

[0016] One end of the first rectifier diode is connected to the same-name end of the first secondary winding coil, and the other end is connected to the positive output end via the positive output bus;

[0017] One end of the second rectifier diode is connected to the opposite end of the second secondary winding coil, and the other end is connected to the positive output terminal via the positive output bus; the center point of the secondary winding is connected to the negative output terminal via the negative output bus.

[0018] In some of the embodiments, the secondary side rectification circuit further includes a current limiting resistor and a secondary side filtering circuit; wherein,

[0019] The current limiting resistor is arranged on the positive output bus and is located between the connection point of the first rectifier diode and the second rectifier diode on the positive output bus and the positive output terminal;

[0020] One end of the secondary filter circuit is connected to the positive output bus, and the other end is connected to the negative output bus.

[0021] In some embodiments, the primary push-pull circuit further includes a first capacitor and a second capacitor; wherein,

[0022] One end of the first capacitor is connected to the connection line between the first power supply and the driving chip, and the other end is grounded;

[0023] One end of the second capacitor is connected to a connecting line between the second power supply and the center point of the primary winding, and the other end is grounded.

[0024] In some of the embodiments, the primary push-pull circuit further includes a first filtering circuit and a second filtering circuit; wherein,

[0025] One end of the first filter circuit is connected to the connecting line between the first primary winding coil and the first switch tube, and the other end is grounded;

[0026] One end of the second filter circuit is connected to the connecting line of the second primary winding coil and the second switch tube, and the other end is grounded.

[0027] In some of the embodiments, the turns ratio of the primary winding to the secondary winding is less than or equal to the ratio of the DC voltage value of the second power supply input to the target DC voltage value output by the secondary rectifier circuit; wherein the number of turns of the first primary winding coil is the same as the number of turns of the second primary winding coil, and the number of turns of the first secondary winding coil is the same as the number of turns of the second secondary winding coil.

[0028] In some embodiments, the DC voltage value of the second power input is greater than the DC voltage value of the first power input, and the DC voltage value of the second power input is less than or equal to half of the breakdown voltage value of the switch tube in the driver chip.

[0029] In some of the embodiments, the boost drive circuit further includes a secondary voltage doubling circuit, which is connected to the secondary winding and used between the secondary rectification circuit to perform voltage doubling and rectification processing on the boosted AC voltage.

[0030] In some of the embodiments, the driver chip further includes a ground pin and a power pin, wherein the ground pin is used to achieve grounding of the driver chip, and the power pin is connected to the first power supply.

[0031] The beneficial effects of the embodiments of the present invention are as follows: by adopting a boost driving circuit including a driving chip, a primary push-pull circuit, a secondary rectifier circuit, a first power supply and a second power supply, wherein the first power supply is connected to the driving chip and is used to supply power to the driving chip; the driving chip is integrated with a first switch tube and a second switch tube, and the driving chip is used to control the conduction and disconnection of the first switch tube and the second switch tube; the second power supply is connected to the primary push-pull circuit and is used to input a DC voltage to the primary push-pull circuit; one end of the primary push-pull circuit is connected to the first switch tube, and the other end is connected to the second switch tube, and is used to convert the DC voltage into an AC voltage and perform a boost processing; the secondary rectifier circuit is connected to the primary push-pull circuit and is used to convert the boosted AC voltage into an AC voltage; The technical means of rectifying and outputting the target DC voltage overcomes the problems of narrow output voltage range, large transformer turns ratio and volume, high transformer cost and low working efficiency of the driving circuit in the related technology. By adopting a first power supply for powering the driving chip and a second power supply for powering the transformer as two power inputs, the second power supply is no longer limited by the power supply voltage of the driving chip, thereby achieving the purpose of increasing the input voltage in the boost driving circuit, thereby achieving the technical effect of expanding the output voltage range, improving the transformer efficiency, and thus improving the working efficiency of the boost driving circuit while reducing the number of turns, reducing the volume of the transformer, and reducing the cost of the transformer.

[0032] The details of one or more embodiments of the invention are set forth in the following drawings and description so that other features, objects, and advantages of the invention are more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other embodiments can be obtained based on these drawings without creative work.

[0034] Figure 1 1 is a circuit diagram of a boost driving circuit according to an embodiment of the present invention.

[0035] Figure 2 It is a circuit topology diagram of a boost driving circuit according to another embodiment of the present invention. DETAILED DESCRIPTION

[0036] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0037] In the boost drive circuit based on the push-pull transformer in the related art, an input power supply is used as both the power supply of the driver chip so that the driver chip controls the conduction and disconnection of the switch tube, and as the input power supply of the transformer, so as to output the target voltage through voltage conversion. Among them, the power supply voltage of the driver chip is generally 3-5V. If you want to output an output voltage of 20V, the transformer turns ratio needs to be 1:4. Considering that the primary winding of the transformer requires a certain initial inductance to avoid overcurrent, the actual turns ratio needs to be increased to 20:80, that is, the turns ratios of the four windings of the transformer are 20:20:80:80 respectively. If there are still requirements for the output power, such as 2W, considering the wire diameter and number of turns in the transformer, the transformer volume will increase. That is, but limited by the low voltage of the power supply of the driver chip, if you want to output a wider output voltage, the turns ratio and volume of the transformer will increase, which will increase the transformer cost and transformer efficiency, making the working efficiency of the drive circuit low.

[0038] In order to solve the above problems, an embodiment of the present invention provides a boost driving circuit, such as Figure 1 As shown, the boost drive circuit includes: a drive chip, a primary push-pull circuit, a secondary rectifier circuit, a first power supply and a second power supply; wherein the first power supply is connected to the drive chip for supplying power to the drive chip; the drive chip is integrated with a first switch tube and a second switch tube, and the drive chip is used to control the conduction and disconnection of the first switch tube and the second switch tube; the second power supply is connected to the primary push-pull circuit for inputting a DC voltage to the primary push-pull circuit; one end of the primary push-pull circuit is connected to the first switch tube, and the other end is connected to the second switch tube, for converting the DC voltage into an AC voltage and performing a boost process; the secondary rectifier circuit is connected to the primary push-pull circuit for rectifying the boosted AC voltage and outputting a target DC voltage.

[0039] like Figure 1 As shown, the boost driving circuit provided in the embodiment of the present invention provides two power supplies; wherein the first power supply V CC Power the driver chip U1, the second power supply V INThe primary push-pull circuit is powered to drive the push-pull transformer, so that the input voltage of the primary push-pull circuit is higher, thereby reducing the number of turns, volume and cost of the transformer, increasing the output voltage range, and improving the working efficiency of the circuit. Specifically, the first power supply VCC powers the driver chip U1, so that the driver chip U1 controls the alternating conduction and disconnection of the first switch tube Q1 and the second opening tube Q2.

[0040] In some embodiments, the primary push-pull circuit includes a primary winding, a push-pull transformer and a secondary winding; wherein the primary winding includes a first primary winding coil and a second primary winding coil wound in parallel, the same-name end of the first primary winding coil is connected to the first switch tube in the driver chip, the opposite-name end of the second primary winding coil is connected to the second switch tube in the driver chip, and the second power supply is connected to the center point of the primary winding; the secondary winding includes a first secondary winding coil and a second secondary winding coil wound in parallel, and the secondary winding is symmetrically arranged with the primary winding.

[0041] like Figure 1 As shown, when the first switch tube Q1 is turned on and the second switch tube Q2 is turned off, the second power supply V IN The primary push-pull circuit is powered, and the current flows to the first switch tube Q1 through the first primary winding coil N1, and then to the ground; when the second switch tube Q2 is turned on and the first switch tube Q1 is turned off, the second power supply V IN The primary push-pull circuit is powered, and the current flows to the second switch tube Q1 through the second primary winding coil N2, and then to the ground; accordingly, an AC voltage is generated in the primary winding, and is transmitted to the secondary winding through the magnetic coupling of the push-pull transformer to generate a higher AC voltage in the secondary winding, thereby achieving a boost operation. The boosted AC voltage is rectified by the secondary rectifier circuit to obtain a stable DC voltage output.

[0042] Among them, the primary winding and the secondary winding provided in the embodiment of the present invention are both wound in parallel, which helps to reduce the influence of leakage inductance and improve the efficiency of the transformer. At the same time, if the secondary winding is asymmetrical with the primary winding, the leakage inductance will increase, thereby affecting the efficiency and stability of the transformer. Therefore, in the embodiment of the present invention, the primary winding and the secondary winding are symmetrically arranged. When the current in the primary winding changes, the secondary winding will also induce a corresponding voltage, thereby generating a higher voltage in the secondary winding. Through the above-mentioned arrangement, the influence of leakage inductance is further reduced, and it is also helpful to reduce the imbalance of the electromagnetic field when the asymmetrical arrangement is used, thereby reducing the response of electromagnetic interference and significantly improving the efficiency and stability of the transformer.

[0043] In some of the embodiments, the secondary rectifier circuit includes a first rectifier diode and a second rectifier diode; wherein, one end of the first rectifier diode is connected to the same-name end of the first secondary winding coil, and the other end is connected to the positive output end via the positive output bus; one end of the second rectifier diode is connected to the opposite-name end of the second secondary winding coil, and the other end is connected to the positive output end via the positive output bus; the center point of the secondary winding is connected to the negative output end via the negative output bus.

[0044] like Figure 1 As shown, the first rectifier diode D1 is connected to the same-name end of the first secondary winding coil N3, and the second rectifier diode D2 is connected to the opposite-name end of the second secondary winding coil N4, thereby rectifying the boosted AC voltage generated in the secondary winding to obtain a stable DC voltage output.

[0045] In some of the embodiments, the secondary rectifier circuit further includes a current limiting resistor and a secondary filter circuit; wherein the current limiting resistor is arranged on the positive output bus and is located between the connection point of the first rectifier diode and the second rectifier diode on the positive output bus and the positive output terminal; one end of the secondary filter circuit is connected to the positive output bus, and the other end is connected to the negative output bus.

[0046] like Figure 2 As shown, the current limiting resistor R3 is arranged on the positive output bus and is located between the connection point of the first rectifier diode and the second rectifier diode on the positive output bus and the positive output terminal. On the one hand, the current limiting resistor R3 can be used to limit the output current to prevent the output current from exceeding the maximum bearing capacity of the circuit, thereby protecting the circuit from damage; on the other hand, the current limiting resistor can also play a certain voltage stabilizing role, making the output voltage more stable.

[0047] The secondary filter circuit can smooth the output voltage, eliminate ripples, and improve the quality of the output voltage. According to a specific implementation of the embodiment of the present invention, Figure 2 As shown, the secondary side filtering circuit may be capacitors C7 and C8 connected in parallel. When the output voltage fluctuates greatly, the capacitors C7 and C8 may absorb the voltage fluctuation, thereby improving the quality of the output voltage.

[0048] In some embodiments, the primary push-pull circuit further includes a first capacitor and a second capacitor; wherein, one end of the first capacitor is connected to a connecting line between the first power supply and the driving chip, and the other end is grounded; one end of the second capacitor is connected to a connecting line between the second power supply and the center point of the primary winding, and the other end is grounded.

[0049] The first capacitor and the second capacitor provided in the embodiment of the present invention are decoupling capacitors, which are used to eliminate high-frequency noise and transient voltage fluctuations on the power supply line to maintain the stability of the power supply. In addition, the decoupling capacitor can also help absorb transient current spikes in the circuit to prevent the power supply voltage from dropping too much.

[0050] like Figure 2 As shown, according to a specific implementation of an embodiment of the present invention, the first capacitor may be C1 and C2 connected in parallel, and the second capacitor may be C5 and C6 connected in parallel. The use of two capacitors in parallel can increase the total capacitance, thereby better absorbing the high-frequency noise in the power supply; at the same time, it can also disperse the capacitance value, thereby reducing the capacitance value deviation and improving the stability of the circuit. It is understandable that the number and connection method of the capacitance in the first capacitor and the second capacitor are not intended to limit the present invention and can be adjusted according to actual circumstances.

[0051] In some embodiments, the primary push-pull circuit further includes a first filter circuit and a second filter circuit; wherein, one end of the first filter circuit is connected to the connecting line between the first primary winding coil and the first switch tube, and the other end is grounded; one end of the second filter circuit is connected to the connecting line between the second primary winding coil and the second switch tube, and the other end is grounded.

[0052] By adding a filter circuit, high-frequency noise in the primary winding can be filtered out, thereby improving the stability of the circuit. At the same time, the filter circuit can also help the circuit better respond to transient load changes and improve the dynamic performance of the circuit.

[0053] like Figure 2 As shown, according to a specific implementation of an embodiment of the present invention, the filter circuit can adopt an RC filter circuit, that is, the first filter circuit includes a capacitor C3 and a resistor R1 connected in series, and the second filter circuit includes a capacitor C4 and a resistor R2 connected in series. It can be understood that other forms of filter circuits that can achieve a filtering function can also be adopted.

[0054] In some of the embodiments, the turns ratio of the primary winding to the secondary winding is less than or equal to the ratio of the DC voltage value of the second power supply input to the target DC voltage value output by the secondary rectifier circuit; wherein the number of turns of the first primary winding coil is the same as the number of turns of the second primary winding coil, and the number of turns of the first secondary winding coil is the same as the number of turns of the second secondary winding coil.

[0055] In the boost drive circuit based on the push-pull transformer, the turns ratio of the primary winding to the secondary winding is a very important parameter, which determines the output voltage. Theoretically, the turns ratio of the primary winding to the secondary winding is equal to the ratio of the input voltage value to the output voltage value, but considering the voltage loss in the circuit, the turns ratio can be set to be slightly smaller than the ratio of the DC voltage value of the second power supply input to the target DC voltage value output by the secondary rectifier circuit.

[0056] According to a specific implementation of the embodiment of the present invention, in actual application, the power supply voltage of the driver chip is relatively small, such as the Vcc power supply in the device specification of a driver chip is a maximum of 3 to 5V. CC , and if you want to output a target output voltage of 20V, a turns ratio of 1:4 is required. Considering that the primary winding of the transformer requires a certain initial inductance to avoid overcurrent, the actual turns of the four windings in the transformer are 20:20:80:80 respectively. In this case, the transformer needs more turns, a larger volume, and a higher cost. Using a separate second power supply can increase the voltage value of the input voltage. If a 12V second power supply Vin is used, the same target output voltage of 20V is output, and only a theoretical turns ratio of 3:5 is required. Even if the voltage loss in the circuit is taken into consideration, the actual turns of the four windings in the transformer are 20:20:35:35 respectively.

[0057] When the current in the primary winding changes, the secondary winding will also induce a corresponding voltage, thereby generating a higher voltage in the secondary winding. Therefore, the number of turns of the first primary winding coil is set to be the same as the number of turns of the second primary winding coil, and the number of turns of the first secondary winding coil is set to be the same as the number of turns of the second secondary winding coil, which helps to reduce the influence of leakage inductance and improve the efficiency of the transformer.

[0058] In some embodiments, the DC voltage value of the second power input is greater than the DC voltage value of the first power input, and the DC voltage value of the second power input is less than or equal to half of the breakdown voltage value of the switch tube in the driver chip.

[0059] Through the above-mentioned setting, the voltage value of the second power supply (i.e., the input voltage in the primary push-pull circuit) is expanded while avoiding overloading the switching tube, which helps to reduce the number of turns, reduce the size of the transformer, reduce the cost of the transformer, and expand the output voltage range, thereby improving the transformer efficiency and thus improving the working efficiency of the boost drive circuit.

[0060] In some of the embodiments, the boost drive circuit further includes a secondary voltage doubling circuit, which is connected to the secondary winding and used between the secondary rectification circuit to perform voltage doubling and rectification processing on the boosted AC voltage.

[0061] The above configuration provides an extended circuit of an embodiment of the present invention, that is, a secondary voltage doubling circuit is added to the original boost drive circuit, so as to perform a further boost process on the boosted AC voltage, further expanding the output voltage range. The secondary voltage doubling circuit is usually composed of a capacitor and a diode, which can convert the AC voltage in the secondary winding into a higher DC voltage.

[0062] In some of the embodiments, the driver chip further includes a ground pin and a power pin, wherein the ground pin is used to ground the driver chip, and the power pin is connected to the first power supply.

[0063] like Figure 1 or Figure 2 As shown, the driver chip U1 includes ground pins (GND) 4 and 5, which are used to connect the ground wire of the driver chip with the ground wire of the circuit to ensure the normal operation of the circuit. CC ) is used to provide power to the driver chip so that it can work normally.

[0064] The boost drive circuit provided in the embodiment of the present invention adopts a circuit topology structure including a driver chip, a primary push-pull circuit, a secondary rectifier circuit, a first power supply and a second power supply, wherein the first power supply is connected to the driver chip and is used to supply power to the driver chip; the driver chip is integrated with a first switch tube and a second switch tube, and the driver chip is used to control the conduction and disconnection of the first switch tube and the second switch tube; the second power supply is connected to the primary push-pull circuit and is used to input a DC voltage to the primary push-pull circuit; one end of the primary push-pull circuit is connected to the first switch tube, and the other end is connected to the second switch tube, and is used to convert the DC voltage into an AC voltage and perform a boost process; the secondary rectifier circuit is connected to the primary push-pull circuit and is used to convert the boosted AC voltage into an AC voltage. The technical means of rectifying the voltage and outputting the target DC voltage overcomes the problems of narrow output voltage range, large transformer turns ratio and volume, high transformer cost and low working efficiency of the driving circuit in the related technology. By adopting a first power supply for powering the driving chip and a second power supply for powering the transformer as two power inputs, the second power supply is no longer limited by the power supply voltage of the driving chip, thereby achieving the purpose of increasing the input voltage in the boost driving circuit, thereby achieving the technical effect of expanding the output voltage range, improving the transformer efficiency, and thus improving the working efficiency of the boost driving circuit while reducing the number of transformer turns, reducing the transformer volume, and reducing the transformer cost.

[0065] The computer programs for implementing the methods of the embodiments of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer programs are executed by the processor or controller, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer programs may be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0066] In the context of an embodiment of the present invention, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable signal medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, or infrared systems, devices, or equipment, or any suitable combination of the foregoing. More specific examples of machine-readable storage media may include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0067] It should be noted that the term "including" and its variations used in the embodiments of the present invention are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "multiple" mentioned in the embodiments of the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless the context clearly indicates otherwise, it should be understood as "one or more".

[0068] The various steps described in the method implementation methods provided in the embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method implementation methods may include additional steps and / or omit the steps shown. The scope of protection of the present invention is not limited in this respect.

[0069] The term "embodiment" in this specification refers to specific features, structures or characteristics described in conjunction with the embodiment that can be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor does it mean that it is mutually exclusive with other embodiments and is independent or optional. The various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments refer to each other. In particular, for the device, equipment, and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts refer to the partial description of the method embodiment.

[0070] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of protection. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A boost drive circuit, characterized in that: include: A driving chip, a primary side push-pull circuit, a secondary side rectifier circuit, a first power supply and a second power supply; wherein, The first power supply is connected to the driving chip and is used to supply power to the driving chip; The driver chip integrates a first switch tube and a second switch tube, and the driver chip is used to control the on and off of the first switch tube and the second switch tube; The second power supply is connected to the primary push-pull circuit and is used to input a DC voltage to the primary push-pull circuit; One end of the primary push-pull circuit is connected to the first switch tube, and the other end is connected to the second switch tube, and is used to convert the DC voltage into an AC voltage and perform a voltage boost process; The secondary side rectifier circuit is connected to the primary side push-pull circuit and is used for rectifying the boosted AC voltage and outputting a target DC voltage.

2. The circuit according to claim 1, characterized in that The primary push-pull circuit includes a primary winding, a push-pull transformer and a secondary winding; wherein, The primary winding comprises a first primary winding coil and a second primary winding coil wound in parallel, the same-name end of the first primary winding coil is connected to the first switch tube in the driving chip, the opposite-name end of the second primary winding coil is connected to the second switch tube in the driving chip, and the second power supply is connected to the center point of the primary winding; The secondary winding includes a first secondary winding coil and a second secondary winding coil which are wound in parallel, and the secondary winding is symmetrically arranged with respect to the primary winding.

3. The circuit according to claim 2, characterized in that The secondary side rectifier circuit includes a first rectifier diode and a second rectifier diode; wherein, One end of the first rectifier diode is connected to the same-name end of the first secondary winding coil, and the other end is connected to the positive output end via the positive output bus; One end of the second rectifier diode is connected to the opposite end of the second secondary winding coil, and the other end is connected to the positive output end via a positive output bus; the center point of the secondary winding is connected to the negative output end via a negative output bus.

4. The circuit according to claim 3, characterized in that The secondary side rectifier circuit also includes a current limiting resistor and a secondary side filter circuit; wherein, The current limiting resistor is arranged on the positive output bus and is located between the connection point of the first rectifier diode and the second rectifier diode on the positive output bus and the positive output terminal; One end of the secondary filter circuit is connected to the positive output bus, and the other end is connected to the negative output bus.

5. The circuit according to claim 2, characterized in that The primary side push-pull circuit further includes a first capacitor and a second capacitor; wherein, One end of the first capacitor is connected to the connection line between the first power supply and the driving chip, and the other end is grounded; One end of the second capacitor is connected to a connecting line between the second power source and the center point of the primary winding, and the other end is grounded.

6. The circuit according to claim 2, characterized in that The primary side push-pull circuit also includes a first filter circuit and a second filter circuit; wherein, One end of the first filter circuit is connected to the connecting line between the first primary winding coil and the first switch tube, and the other end is grounded; One end of the second filter circuit is connected to the connecting line between the second primary winding coil and the second switch tube, and the other end is grounded.

7. The circuit according to claim 2, characterized in that The turns ratio of the primary winding to the secondary winding is less than or equal to the ratio of the DC voltage value of the second power supply input to the target DC voltage value output by the secondary rectifier circuit; wherein the number of turns of the first primary winding coil is the same as the number of turns of the second primary winding coil, and the number of turns of the first secondary winding coil is the same as the number of turns of the second secondary winding coil.

8. The circuit according to claim 1, characterized in that The DC voltage value of the second power supply input is greater than the DC voltage value of the first power supply input, and the DC voltage value of the second power supply input is less than or equal to half of the breakdown voltage value of the switch tube in the driver chip.

9. The circuit according to claim 1, characterized in that The boost drive circuit also includes a secondary voltage doubling circuit, which is connected to the secondary winding and used between the secondary rectifier circuit to perform voltage doubling and rectification processing on the boosted AC voltage.

10. The circuit according to claim 1, characterized in that The driving chip further includes a ground pin and a power pin, wherein the ground pin is used to achieve grounding of the driving chip, and the power pin is connected to the first power supply.

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