Voltage transformation circuit, driving power board and power supply circuit

Abstract

The utility model relates to the field of electric control, in particular to a voltage transformation circuit, a driving power board and a power supply circuit. The voltage transformation circuit comprises a voltage input end; the power management module is used for power supply management and is connected with the voltage input end; each voltage transformation module comprises a transformer, each transformer comprises a first primary winding, the first primary windings of the voltage transformation modules are arranged in parallel to form a parallel circuit, the input end of the parallel circuit is connected with the voltage input end, and the output end of the parallel circuit is connected with the power management module. The first primary windings of the multiple voltage transformation modules are arranged in parallel to form the parallel circuit, so that the multiple voltage transformation modules can share one power management module, the number of the power management modules in the voltage transformation circuit is reduced, the size of the voltage transformation circuit is reduced, and the cost of the voltage transformation circuit is reduced. And the cost and the failure risk rate of the circuit board integrated with the voltage transformation circuit are reduced.

Description

Technical Field

[0001] The present application relates to the field of electric control technology, and in particular to a voltage transformer circuit, a driving power board and a power supply circuit. Background Art

[0002] Transformers are important components in electronic control systems. In electronic control systems, when using traditional transformers such as plug-in transformers or surface-mount transformers, it is necessary not only to consider parameters such as the height, leakage inductance, and junction capacitance of the traditional transformer, but also to design the position of the traditional transformer in combination with the temperature and other properties of the equipment. Furthermore, electronic control systems usually require three transformers to drive three-phase upper and lower bridge switches and other power devices. In related technologies, three power management modules are required when three transformers drive three upper and lower bridges, which increases the cost of the circuit board and the risk of failure.

[0003] Therefore, at present, there is an urgent need to optimize the design of the transformer. Utility Model Content

[0004] Based on this, it is necessary to provide a better transformer design solution.

[0005] In one aspect, a voltage conversion circuit is provided, comprising:

[0006] Voltage input terminal;

[0007] A power management module, used for power supply management;

[0008] Multiple transformer modules, each transformer module includes a transformer, each transformer includes a first primary winding, multiple first primary windings of the multiple transformer modules are arranged in parallel to form a parallel circuit, and the input end of the parallel circuit is connected to the voltage input end, and the output end of the parallel circuit is connected to the power management module.

[0009] In some embodiments, the power management module includes an interconnected power management chip and a feedback circuit, the multiple transformer modules include a target transformer module, the transformer of the target transformer module includes a second primary winding, the second primary winding is connected to the feedback circuit, and the power management chip is connected to the output end of the parallel circuit and the feedback circuit.

[0010] In some embodiments, the power management module includes a detection circuit, which connects the output end of the parallel circuit and the power management chip. The detection circuit is used to detect the output current of the parallel circuit and output the output current of the parallel circuit to the power management chip.

[0011] In some embodiments, the power management module includes a switch circuit, the switch circuit is connected between the power management chip and the output end of the parallel circuit, and the detection circuit is connected between the switch circuit and the power management chip.

[0012] In some embodiments, the voltage conversion circuit includes an absorption circuit, one end of the absorption circuit is connected to the input end of the parallel circuit, and the other end of the absorption circuit is connected to the output end of the parallel circuit, and the absorption circuit is used to absorb peak voltage.

[0013] In some embodiments, each of the transformers includes a first secondary winding and a second secondary winding, and each of the transformer modules includes a Zener tube-type upper bridge drive circuit and a lower bridge drive circuit, each of the first secondary windings is connected to the upper bridge drive circuit, and each of the second secondary windings is connected to the lower bridge drive circuit.

[0014] In one aspect, a driving power board is provided, comprising: a multi-layer electrically connected planar circuit board, wherein the multi-layer electrically connected planar circuit board is integrated with the aforementioned voltage conversion circuit.

[0015] In some embodiments, the power management module includes a feedback circuit, which is integrated into a planar circuit board located in the middle layer, and the feedback circuit is surrounded by secondary windings of different transformers.

[0016] In some embodiments, the multiple transformer modules include a target transformer module, the transformer of the target transformer module includes a second primary winding, the second primary winding is connected to the feedback circuit, each of the transformers includes a first secondary winding and a second secondary winding, the multi-layer electrically connected planar circuit board includes a first circuit board, a second circuit board and a third circuit board, the first circuit board is provided with the first secondary winding of the multiple transformer modules, the second circuit board is provided with the feedback circuit and the second secondary winding of the remaining transformer modules except the target transformer module, and the third circuit board is provided with the second secondary winding of the target transformer module.

[0017] In one aspect, a power supply circuit is provided, comprising:

[0018] Auxiliary power supply;

[0019] A control chip connected to the auxiliary power supply, wherein the auxiliary power supply supplies power to the control chip;

[0020] As in the aforementioned voltage conversion circuit, the output end of the voltage conversion circuit is electrically connected to the control chip.

[0021] The above-mentioned transformer circuit forms a parallel circuit by setting multiple first primary windings of multiple transformer modules in parallel, so that multiple transformer modules can share a power management module, thereby reducing the number of power management modules in the transformer circuit, thereby reducing the volume of the transformer circuit, and reducing the cost and failure risk rate of the circuit board integrated with the transformer circuit. Furthermore, integrating the above-mentioned transformer circuit on the planar circuit board of the driving power board can not only improve the temperature resistance of the driving power board, but also increase the consistency of each transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A voltage conversion circuit provided by an embodiment;

[0024] Figure 2 A voltage conversion circuit in the related art;

[0025] Figure 3 A schematic diagram of a leakage inductance equivalent model provided by an embodiment;

[0026] Figure 4 A schematic diagram of an upper bridge driving circuit or a lower bridge driving circuit provided by an embodiment;

[0027] Figure 5 A schematic diagram of a power supply circuit provided by an embodiment.

[0028] Explanation of the accompanying drawings: transformer circuit-100; voltage input terminal-110; power management module-120; power management chip-121; feedback circuit-122; detection circuit-123; switching circuit-124; absorption circuit-125; filtering circuit-126; transformer module-130; first primary winding-131; second primary winding-132; first secondary winding-133; second secondary winding-134; upper bridge drive circuit-135; lower bridge drive circuit-136; control chip-200; auxiliary power supply-210; motor-220.

[0029] In order to better describe and illustrate the embodiments and / or examples of the utility models disclosed herein, reference may be made to one or more drawings. The additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed utility models, the embodiments and / or examples currently described, and the best modes of these utility models currently understood. DETAILED DESCRIPTION

[0030] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0032] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0033] In each embodiment, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For ordinary technicians in this field, the specific meanings of the above terms in each embodiment can be understood according to the specific circumstances. It can be understood that the "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if the connected circuits, modules, units, etc. have the transmission of electrical signals or data with each other.

[0034] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0035] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0036] like Figure 1 As shown, in one embodiment, a voltage conversion circuit is provided. The voltage conversion circuit 100 includes a voltage input terminal 100 , a power management module 120 and a plurality of voltage conversion modules 130 .

[0037] The voltage input terminal 100 can be used to connect a power source such as a low-voltage battery. As an example, the voltage input terminal 100 can input a voltage between 18V and 32V to the voltage conversion circuit 100 .

[0038] The power management module 120 may be used to manage the power supply of the voltage conversion circuit 100. For example, the power management module 120 may manage whether the voltage conversion circuit 100 is turned on.

[0039] The voltage transformation module 130 can be used to change the voltage input by the voltage input terminal 100. The voltage transformation circuit 100 may include a plurality of voltage transformation modules 130. For example, the voltage transformation circuit 100 may include three voltage transformation modules 130. At this time, the three voltage transformation modules 130 may be a U-phase voltage transformation module, a V-phase voltage transformation module, and a W-phase voltage transformation module. Of course, the voltage transformation circuit 100 may include four, five, or other numbers of voltage transformation modules 130. This embodiment does not specifically limit the number of voltage transformation modules 130.

[0040] Each transformer module 130 includes a transformer. Each transformer includes a first primary winding 131. Multiple first primary windings 131 of multiple transformer modules 130 are connected in parallel to form a parallel circuit. Moreover, at this time, the input end of the parallel circuit is connected to the voltage input end 100, and the output end of the parallel circuit is connected to the power management module 120.

[0041] In this embodiment, a plurality of first primary windings 131 of a plurality of transformer modules 130 are connected in parallel to form a parallel circuit, so that the plurality of transformer modules 130 can share one power management module 120. Figure 2In the related art, each phase transformer circuit is provided with a power management module, and each power management module manages a transformer, which is not conducive to the miniaturization of the transformer circuit. This embodiment reduces the number of power management modules 120 in the transformer circuit 100, saves the cost of preparing the power management module, reduces the volume of the transformer circuit 100, and reduces the cost and failure risk rate of the integrated circuit board of the transformer circuit 100.

[0042] In one embodiment, the power management module 120 includes a power management chip 121 and a feedback circuit 122 that are connected to each other.

[0043] Among the plurality of transformer modules 130 , any transformer module 130 may be determined as a target transformer module 130 . As an example, a V-phase transformer module may be the target transformer module 130 .

[0044] The transformer of the target voltage transformation module 130 includes a second primary winding 132. The second primary winding 132 is connected to the feedback circuit 122. The power management chip 121 is connected to the output end of the parallel circuit and the feedback circuit 122.

[0045] When a power source such as a low-voltage battery inputs a voltage to the transformer circuit 100 through the voltage input terminal 100, multiple transformers work. The feedback circuit 122 can obtain a feedback voltage or current through the second primary winding 132, and the feedback voltage or current can accurately and quickly reflect the working status of multiple transformers. The power management chip 121 is connected to the feedback circuit 122 to determine the working status of the transformer. Exemplarily, the feedback circuit 122 may include a unidirectional conduction element, and according to the feedback voltage or current output by the second primary winding 132, the unidirectional conduction element is set to be in an on or off state, so that the power management chip 121 can obtain a high level or a low level, and determine the working status of multiple transformers according to the high level or the low level.

[0046] In this embodiment, the transformer circuit 100 is configured to include a feedback circuit 122 , and the working states of multiple transformers can be quickly obtained through the feedback circuit 122 , thereby further reducing the size of the transformer circuit 100 .

[0047] In one embodiment, the power management module 120 includes a detection circuit 123 .

[0048] The detection circuit 123 is connected to the output end of the parallel circuit and the power management chip 121. The detection circuit 123 is used to detect the output current of the parallel circuit and output the output current of the parallel circuit to the power management chip 121. Exemplarily, the detection circuit 123 may include components such as an operational amplifier. One input end of the operational amplifier is connected to the output end of the parallel circuit, and the other input end is connected to the reference power supply. The output end of the operational amplifier can be connected to the power management chip 121.

[0049] In this embodiment, the detection circuit 123 is provided to quickly determine the working state of the power management chip 121 or the parallel circuit.

[0050] In one embodiment, the power management module 120 includes a switch circuit 124 .

[0051] The switch circuit 124 is connected between the power management chip 121 and the output end of the parallel circuit. The detection circuit 123 is connected between the switch circuit 124 and the power management chip 121. Exemplarily, the switch circuit 124 may include a plurality of field effect transistors, wherein the gate of the field effect transistor may be connected to the power management chip 121, and the source and drain of the field effect transistor are respectively connected to the power management chip 121 and the parallel circuit.

[0052] In this embodiment, the power management chip 121 can control the on and off of each switch element in the switch circuit 124, so as to quickly control the working state of the transformer circuit 100. Furthermore, in this embodiment, a detection circuit 123 is provided to be connected between the switch circuit 124 and the power management chip 121, so that when the detection circuit 123 detects an abnormal situation such as overvoltage or overcurrent in the transformer circuit 100, the power management chip 121 can quickly disconnect the switch circuit 124.

[0053] In one embodiment, the voltage conversion circuit 100 includes an absorption circuit 125 .

[0054] The absorption circuit 125 is used to absorb the peak voltage. One end of the absorption circuit 125 is connected to the input end of the parallel circuit, and the other end is connected to the output end of the parallel circuit. As an example, the absorption circuit 125 can be an RCD clamping circuit. The RCD clamping circuit can include a clamping resistor and a clamping capacitor arranged in parallel. In addition, the RCD clamping circuit can also include components such as a clamping diode.

[0055] See also Figure 3 It can be understood that in the conventional technology, the single-path leakage inductance of each transformer module 130 is L. In this embodiment, multiple first primary windings 131 of multiple transformer modules 130 are arranged in parallel, and the overall leakage inductance is equivalent to L / 3. Please refer to the RCD clamping absorption power calculation formula:

[0056]

[0057] Among them, P clamp Indicates the power consumed by the clamp resistor, f s is the operating frequency of the transformer, L k is the leakage inductance of the primary winding, I p is the maximum peak current of the clamping diode, V clampRepresents the voltage across the clamp capacitor, V OR It represents the refracted voltage from secondary to primary. From the above formula, we can get that in the RCD clamping circuit, L k That is, the parallel arrangement of the plurality of first primary windings 131 of the plurality of transformer modules 130 can make the power consumed by the clamping resistor smaller, thereby improving the transformer efficiency.

[0058] In this embodiment, a plurality of first primary windings 131 of a plurality of transformer modules 130 are connected in parallel to form a parallel circuit, thereby reducing the power consumed by the absorption resistor of the absorption circuit 125 and improving the transformer efficiency.

[0059] In addition, the power management module 120 includes a filter circuit 126. The filter circuit 126 can be connected between the voltage input terminal 110 and the first primary winding 131. The filter circuit 126 is used to filter out unnecessary bands input from the voltage input terminal 110. Exemplarily, the filter circuit 126 can include a capacitor and an inductor to filter out a high frequency band or a low frequency band.

[0060] In one embodiment, each transformer includes a first secondary winding 133 and a second secondary winding 134. Each transformer module 130 includes a voltage regulator type upper bridge drive circuit 135 and a lower bridge drive circuit 136. Each first secondary winding 133 is connected to the upper bridge drive circuit 135, and each second secondary winding 134 is connected to the lower bridge drive circuit 136.

[0061] As an example, see Figure 4 , the upper bridge drive circuit 135 and the lower bridge drive circuit 136 of the voltage regulator type can adopt a positive voltage stabilized solution ( Figure 4 (a) in the figure), or a stable negative pressure solution ( Figure 4 (b) in the figure), thereby controlling the output rectified voltage to be between 23V and 26V. Figure 4 In the embodiment, the voltage-stabilizing tube type driving circuit may include a diode D1 connected to the upper bridge driving circuit 135 or the lower bridge driving circuit 136 to control the current flow direction. The voltage-stabilizing tube type driving circuit may also be connected in parallel to a capacitor C3 and a voltage-stabilizing tube circuit. The voltage-stabilizing tube circuit includes a resistor R1 and a voltage-stabilizing tube D2 arranged in series. The connection order of the resistor R1 and the voltage-stabilizing tube D2 in the positive voltage-stabilizing scheme or the negative voltage-stabilizing scheme is different. In addition, the voltage-stabilizing tube type driving circuit may also include a capacitor C1 and a capacitor C2 to balance the circuit. One end of the capacitor C1 is connected to the voltage-stabilizing tube circuit, and the other end of the capacitor is connected between the resistor R1 and the voltage-stabilizing tube D2. One end of the capacitor C2 is connected between the resistor R1 and the voltage-stabilizing tube D2, and the other end of the capacitor C2 is connected to the voltage-stabilizing tube circuit.

[0062] In this embodiment, by providing a voltage-stabilizing tube-type upper bridge driving circuit 135 and a lower bridge driving circuit 136 , the volume of the voltage transformer circuit 100 is further reduced.

[0063] Of course, the voltage transformation module 130 may also include a center-tapped driving circuit or other forms of circuits.

[0064] It can be understood that the above-mentioned voltage conversion circuit 100 can also adopt other forms, not limited to the forms mentioned in the above-mentioned embodiments, as long as it can achieve the function of the voltage conversion circuit 100.

[0065] In one embodiment, a driving power board is provided, which includes a multi-layer electrically connected planar circuit board, wherein the multi-layer electrically connected planar circuit board integrates a voltage conversion circuit 100 formed by any one of the above embodiments or a combination of multiple embodiments.

[0066] In this embodiment, the transformer circuit 100 formed by combining any one or more of the foregoing embodiments is integrated onto a multi-layer electrically connected planar circuit board, thereby reducing the distance between the windings, improving the magnetic coupling between the windings, and further reducing the leakage inductance, which is beneficial to improving the electrical stress of the RCD clamping circuit and the clamping diode.

[0067] Moreover, the height of the magnetic core of the planar circuit board is relatively low, which is conducive to the improvement of the structural layout and the power density of the whole machine. At the same time, the heat dissipation and temperature resistance of the planar circuit board are better than those of traditional transformers (plug-in transformers and surface mount transformers). Under high frequency conditions, the copper loss and iron loss of the planar circuit board are relatively low. Furthermore, the magnetic core of the planar transformer contains the winding inside, which has a good shielding effect, which reduces the external radiated electromagnetic compatibility radiation emission interference, and the sensitivity and anti-interference of the planar transformer are also improved accordingly. The irregular winding spacing and manual assembly errors of traditional transformers will cause large differences in transformer performance, while the planar transformer used in this embodiment uses automatic production line technology to easily realize winding and machining, which is conducive to improving the consistency of multiple windings in the driving power board.

[0068] In one embodiment, the power management module 120 includes a feedback circuit 122 . The feedback circuit 122 is integrated in a planar circuit board located at a middle layer. The feedback circuit 122 is surrounded by secondary windings of different transformers.

[0069] Specifically, the plurality of transformer modules 130 include a target transformer module 130, the transformer of the target transformer module 130 includes a second primary winding 132, the second primary winding 132 is connected to the feedback circuit 122, and each transformer includes a first secondary winding 133 and a second secondary winding 134. At this time, please refer to the following table, when the transformer circuit 100 is a U-phase transformer module, a V-phase transformer module, and a W-phase transformer module, the multi-layer electrically connected planar circuit board includes a first circuit board, a second circuit board, a third circuit board, and a fourth circuit board. The first circuit board is provided with a plurality of first secondary windings 133 of the transformer modules 130, the second circuit board is provided with the feedback circuit 122 and the second secondary windings 134 of the remaining transformer modules 130 except the target transformer module 130, and the third circuit board is provided with the second secondary winding 134 of the target transformer module 130. The first primary windings 131 of the remaining plurality of transformer modules 130 are arranged on the fourth circuit board. Of course, the first circuit board and the second circuit board can be interchanged to ensure that the feedback circuit 122 is integrated on the planar circuit board located in the middle layer.

[0070]

[0071]

[0072] In this embodiment, the feedback circuit 122 is disposed on a planar circuit board located in the middle layer, and multiple secondary windings surround the feedback circuit 122, thereby maximizing the coupling degree of multiple transformer modules 130, thereby compensating for the defect that the remaining transformer modules 130 except the target transformer module 130 do not have the feedback circuit 122.

[0073] In one embodiment, see Figure 5 , a power supply circuit is provided. The power supply circuit includes an auxiliary power supply 210, a control chip 200, and a voltage conversion circuit 100 formed by any one of the above embodiments or a combination of multiple embodiments.

[0074] The output end of the voltage conversion circuit 100 is electrically connected to a plurality of control chips 200. Each control chip 200 is connected to an auxiliary power supply 210. The auxiliary power supply 210 supplies power to the control chip 200. As an example, the control chip 200 may be connected to a plurality of switches of a generator 220, and based on the output voltage of the voltage conversion circuit 100, the control chip 200 may control the on and off states of the plurality of switches of the generator 220.

[0075] In this embodiment, a power supply circuit is provided that includes a voltage conversion circuit 100 formed by any one of the aforementioned embodiments or a combination of multiple embodiments, thereby reducing the design cost of the power supply circuit integrated in the auxiliary power supply 210 .

[0076] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0077] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. 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 application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A voltage conversion circuit, characterized in that: include: Voltage input terminal; A power management module, used for power supply management; Multiple transformer modules, each transformer module includes a transformer, each transformer includes a first primary winding, multiple first primary windings of the multiple transformer modules are arranged in parallel to form a parallel circuit, and the input end of the parallel circuit is connected to the voltage input end, and the output end of the parallel circuit is connected to the power management module.

2. The voltage conversion circuit according to claim 1, characterized in that: The power management module includes a power management chip and a feedback circuit that are interconnected. The multiple transformer modules include a target transformer module. The transformer of the target transformer module includes a second primary winding, and the second primary winding is connected to the feedback circuit. The power management chip is connected to the output end of the parallel circuit and the feedback circuit.

3. The voltage conversion circuit according to claim 2, characterized in that: The power management module includes a detection circuit, which is connected to the output end of the parallel circuit and the power management chip. The detection circuit is used to detect the output current of the parallel circuit and output the output current of the parallel circuit to the power management chip.

4. The voltage conversion circuit according to claim 3, characterized in that: The power management module comprises a switch circuit, wherein the switch circuit is connected between the power management chip and an output end of the parallel circuit, and the detection circuit is connected between the switch circuit and the power management chip.

5. The voltage conversion circuit according to claim 1, characterized in that: The voltage conversion circuit comprises an absorption circuit, one end of the absorption circuit is connected to the input end of the parallel circuit, and the other end of the absorption circuit is connected to the output end of the parallel circuit, and the absorption circuit is used to absorb peak voltage.

6. The voltage conversion circuit according to claim 1, characterized in that: Each of the transformers includes a first secondary winding and a second secondary winding, and each of the transformer modules includes a Zener tube-type upper bridge drive circuit and a lower bridge drive circuit. Each of the first secondary windings is connected to the upper bridge drive circuit, and each of the second secondary windings is connected to the lower bridge drive circuit.

7. A driving power board, characterized in that: include: A multi-layer electrically connected planar circuit board, wherein the multi-layer electrically connected planar circuit board integrates the voltage conversion circuit as claimed in any one of claims 1 to 6.

8. The driving power board according to claim 7, characterized in that: The power management module comprises a feedback circuit, which is integrated on a planar circuit board located in the middle layer and is surrounded by secondary windings of different transformers.

9. The driving power board according to claim 8, characterized in that: The multiple transformer modules include a target transformer module, the transformer of the target transformer module includes a second primary winding, the second primary winding is connected to the feedback circuit, each of the transformers includes a first secondary winding and a second secondary winding, the multi-layer electrically connected planar circuit board includes a first circuit board, a second circuit board and a third circuit board, the first circuit board is provided with the first secondary winding of the multiple transformer modules, the second circuit board is provided with the feedback circuit and the second secondary winding of the remaining transformer modules except the target transformer module, and the third circuit board is provided with the second secondary winding of the target transformer module.

10. A power supply circuit, characterized in that: include: Auxiliary power supply; A control chip connected to the auxiliary power supply, the auxiliary power supply supplies power to the control chip ； The voltage transformer circuit according to any one of claims 1 to 6, wherein the output end of the voltage transformer circuit is electrically connected to the control chip.

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