Voltage regulator, circuit module, electronic device and coupling inductor structure

Abstract

Provided in the present application are a voltage regulator, a circuit module, an electronic device and a coupling inductor structure. By means of integrating three windings on a three-leg magnetic core, magnetic coupling and electrical coupling between different inductor windings in a two-phase step-down circuit are implemented, thereby facilitating a reduction in the size of a VRM while optimizing the performance of the VRM. The VRM can be deployed as a power supply solution around a main chip of an ICT-related hardware product (e.g., a server or an AI inference platform device).

Description

Voltage regulator, circuit module, electronic device and coupled inductor structure

[0001] This application claims priority to the Chinese Patent Application No. CN202411071881.6, filed on August 6, 2024, and entitled "Voltage regulator, circuit module, electronic device and coupled inductor structure", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the field of power electronics, and in particular to a voltage regulator, a circuit module, an electronic device and a coupled inductor structure. BACKGROUND

[0003] With the continuous evolution of chips, the clock frequency of the chips is getting faster, the operating voltage is getting lower, the required operating current is getting higher, and the operating current is constantly dynamically adjusted as the operating service changes. The application of voltage regulator module (VRM) for supplying power to the chip is becoming more and more widespread.

[0004] However, as the layout space left for the power supply on the single board continues to decrease, the requirements for the performance (such as steady-state performance and / or dynamic performance) of the VRM continue to increase. How to optimize the performance of the VRM while reducing its volume has become a research hotspot. SUMMARY

[0005] The magnetic coupling and electrical coupling between different inductor windings in a two-phase buck circuit are achieved by a coupled inductor structure with three windings, which is beneficial to optimize the performance of the VRM. However, as more windings need to be wound on the magnetic core, the number of magnetic core columns increases accordingly, for example, three windings need to be integrated on a five-column magnetic core to achieve the magnetic coupling and electrical coupling between different inductor windings in a two-phase buck circuit. This will result in a larger volume of the magnetic core, and in turn increase the volume of the VRM.

[0006] Therefore, the present application provides a voltage regulator, a circuit module, an electronic device and a coupled inductor structure, which integrates three windings on a three-column magnetic core to achieve the magnetic coupling and electrical coupling between different inductor windings in a two-phase buck circuit, which is beneficial to optimize the performance of the VRM while reducing the volume of the VRM. The scheme provided by the present application is introduced below.

[0007] In a first aspect, the present application provides a power supply device, which can be a voltage regulator or the aforementioned VRM. Hereinafter, the power supply device is taken as an example of the VRM. The VRM comprises a capacitor and at least one circuit unit, the circuit unit comprising a coupled inductor structure and two switching circuits. The coupled inductor structure comprises a magnetic core and a plurality of windings integrated on the magnetic core, wherein the magnetic core has three core legs, the plurality of windings comprises a secondary winding and two primary windings, and the plurality of windings are wound on different core legs respectively. The inputs of the two switching circuits are respectively connected to power supplies, the outputs of the two switching circuits are respectively connected to the inputs of the two primary windings, and the outputs of the two primary windings are respectively connected to the capacitor and a load.

[0008] For ease of description, the two switching circuits are respectively referred to as a first switching circuit and a second switching circuit, and the two primary windings are respectively referred to as a first primary winding and a second primary winding. The output of the first switching circuit is connected to the first primary winding, and the output of the second switching circuit is connected to the second primary winding. The output of the primary winding can form a filter circuit after being connected to the capacitor, and therefore, the two switching circuits and the two primary windings can be used to form two-phase buck circuits in the VRM. For ease of description, the two-phase buck circuits are respectively referred to as a first buck circuit and a second buck circuit in the present application, wherein the first buck circuit comprises the first switching circuit and the first primary winding, and the second buck circuit comprises the second switching circuit and the second primary winding.

[0009] By integrating the three windings on the three-leg magnetic core, it is beneficial to realize the magnetic coupling and electrical coupling between the different inductor windings (i.e. the first primary winding and the second primary winding) in the two-phase buck circuits, which not only helps to optimize the performance of the VRM, but also helps to reduce the volume of the magnetic core by reducing the number of core legs, and further reduce the volume of the VRM and improve the power supply efficiency of the VRM.

[0010] Optionally, when the two primary windings are negatively coupled, the two primary windings are positively coupled to the secondary winding respectively.

[0011] A part of the magnetic flux generated by the primary winding (referred to as first magnetic flux) can be used to couple with the other primary winding, another part of the magnetic flux generated by the primary winding (referred to as second magnetic flux) can be used to couple with the secondary winding, and the other part of the magnetic flux generated by the primary winding (referred to as third magnetic flux) is neither used to couple with the other primary winding nor used to couple with the secondary winding, and therefore, the third magnetic flux can be equivalent to leakage inductance.

[0012] The application also provides a method for increasing leakage inductance in a coupled inductor structure with three windings integrated on a three-column magnetic core. By increasing the leakage inductance, it is beneficial to equivalently add an inductance value in series with the secondary winding in the circuit topology of the VRM to meet the dynamic requirement of the secondary inductance (denoted as Lc) of the VRM, thereby avoiding the need to add Lc in series with the secondary winding in the VRM, and further reducing the physical size of the VRM. The magnetic core column with the secondary winding wound thereon is referred to as the first magnetic core column. The possible methods for increasing the leakage inductance are described below.

[0013] In the first method for increasing the leakage inductance, the effective cross-sectional area Ae of the magnetic core on the first magnetic core column for the secondary winding can be smaller than the cross-sectional area of the first magnetic core column, or in other words, the secondary winding is wound on a part of the cross section of the first magnetic core column. In this way, it is beneficial to have only a part of the magnetic flux generated by the primary winding coupled with the secondary winding, thereby increasing the leakage inductance of the primary winding.

[0014] In the second method for increasing the leakage inductance, a material with a relatively low permeability can be selected to manufacture the magnetic core, for example, the material of the magnetic core structure is a metallic magnetic material, and / or the permeability of the material of the magnetic core structure is not more than 100 henry / meter. In this way, it is beneficial to have a part of the magnetic flux generated by the primary winding leak to the surrounding environment outside the magnetic core, thereby increasing the leakage inductance of the primary winding, and also beneficial to reduce the processing difficulty of the magnetic core, facilitating mass production. In addition, compared with ferrite material, the metallic magnetic material (or magnetic powder core material) has a lower permeability, thereby having a higher saturation magnetic density, which is beneficial to reduce the volume of the magnetic core, further reduce the volume of the VRM, and expand the application scenarios of the VRM, for example, it can also be applied to application scenarios with strong demands for volume and height. In the second method for increasing the leakage inductance, Ae of the first magnetic core column for the secondary winding can be equal to the cross-sectional area of the first magnetic core column, or in other words, the secondary winding is wound on the entire cross section of the first magnetic core column.

[0015] In the third method for increasing the leakage inductance, Ae of the first magnetic core column for the secondary winding can be smaller than the cross-sectional area of the first magnetic core column, and the material of the magnetic core structure is a metallic magnetic material and / or the permeability of the material of the magnetic core structure is not more than 100 henry / meter. In this way, it is beneficial to further increase the leakage inductance of the primary winding.

[0016] The application is not limited to the method for realizing Ae of the first magnetic core column for the secondary winding smaller than the cross-sectional area of the first magnetic core column in the coupled inductor structure. Alternatively, the first magnetic core column has a groove, the depth direction of the groove can be perpendicular to the cross-sectional direction of the first magnetic core column or perpendicular to the plane where the secondary winding is located, and the entire or a part of the secondary winding can be installed in the groove, thereby realizing Ae of the first magnetic core column for the secondary winding smaller than the cross-sectional area of the first magnetic core column.

[0017] The foregoing introduces the mounting mode of the secondary winding on the magnetic core. Hereinafter, two magnetic core columns other than the first magnetic core column are referred to as the second magnetic core column and the third magnetic core column respectively. The mounting mode of the primary winding on the magnetic core is introduced as follows.

[0018] The present application refers to the winding part of the primary winding located in the magnetic column gap as the target edge. The magnetic column gap can be the gap between the second magnetic core column and the first magnetic core column (referred to as the first magnetic column gap), or the gap between the third magnetic core column and the first magnetic core column (referred to as the second magnetic column gap). The target edge of the first primary winding can be located in the first magnetic column gap, and the target edge of the second primary winding can be located in the second magnetic column gap.

[0019] The present application refers to the winding part of the secondary winding located in the first magnetic column gap as the first edge, and refers to the winding part of the secondary winding located in the second magnetic column gap as the second edge. The target edge of the first primary winding can be used to couple with the first edge of the secondary winding, and the target edge of the second primary winding can be used to couple with the second edge of the secondary winding.

[0020] In the first mounting mode of the primary winding, the primary winding includes a part of winding (referred to as the other edge) in addition to the target edge, that is, the target edge of the primary winding is used to couple with the secondary winding, and the other edge is not used to couple with the secondary winding. Optionally, the other edge of the first primary winding is wound on the second magnetic core column, and the other edge of the second primary winding is wound on the third magnetic core column. Based on the second or third implementation mode of increasing the leakage inductance, it is beneficial to increase the magnetic flux of the other edge of the primary winding leaking to the surrounding environment outside the magnetic core, thereby further increasing the leakage inductance of the primary winding.

[0021] In the second mounting mode of the primary winding, the two ends of the target edge can be the input end and the output end of the corresponding primary winding respectively, or in other words, the entire primary winding is used to couple with the secondary winding, or the entire primary winding is located in the first magnetic column gap or the second magnetic column gap. For example, the two ends of the target edge of the first primary winding are or are directly connected to the input end and the output end of the first primary winding respectively, and the two ends of the target edge of the second primary winding are or are directly connected to the input end and the output end of the second primary winding respectively. In this way, it is beneficial to shorten the length of the primary winding while ensuring the coupling coefficient of the primary winding and the secondary winding, thereby reducing the loss of the driving signal of the power output in the primary winding, and further improving the power supply efficiency of the VRM to the load.

[0022] The possible mounting mode of the coupled inductor structure on the circuit board is introduced as follows.

[0023] Optionally, the coupled inductor structure is used to be fixed on the surface of the circuit board or buried in the interior of the circuit board.

[0024] In the first mounting mode, at least one winding in the coupled inductance structure is perpendicular to the surface of the circuit board, which is conducive to reducing the area occupied by the coupled inductance structure on the surface of the circuit board, thereby reducing the area of the surface of the circuit board.

[0025] In the second mounting mode, the multiple windings in the coupled inductance structure are respectively parallel to the surface of the circuit board, or the extension direction of the winding in the coupled inductance structure is parallel to the surface of the circuit board. Thus, even if the input end and the output end of the winding are on different surfaces of the coupled inductance structure, for example, the input end and the output end of the primary winding according to the second mounting mode may be located on the opposite surfaces of the coupled inductance structure, it is still conducive to ensuring that the input end and the output end of the winding have the same height relative to the circuit board, thereby shortening the lead length between the input end and the output end of the winding and the PCB, reducing the loss of the driving signal of the power output in the primary winding, and further improving the power supply efficiency of the VRM to the load. In addition, the multiple windings being respectively parallel to the circuit board is also conducive to embedding the coupled inductance structure in the circuit board and using the traces in the circuit board as windings, thereby further reducing the height of the VRM in the single board.

[0026] As introduced in the foregoing, the target side of the first primary winding can be coupled with the first side of the secondary winding, and the target side of the second primary winding can be coupled with the second side of the secondary winding.

[0027] The present application does not limit the deployment orientation (for example, the angle between the coupling surface and the cross section of the magnetic core column / the plane where the secondary winding is located) of the surface (referred to as the first coupling surface) oppositely arranged (or closest) to the target side of the first primary winding and the first side of the secondary winding, nor the deployment orientation of the surface (referred to as the second coupling surface) oppositely arranged (or closest) to the target side of the second primary winding and the second side of the secondary winding.

[0028] In order to increase the coupling coefficient, the area of the first coupling surface can be greater than the area of the adjacent other surfaces, and the area of the second coupling surface can be greater than the area of the adjacent other surfaces.

[0029] In the first deployment orientation of the coupling surface, the coupling surface can be perpendicular to the cross section of the magnetic core column or the plane where the secondary winding is located, wherein the coupling surface can be the first coupling surface and / or the second coupling surface. In this way, it is conducive to tiling the winding along the plane perpendicular to the magnetic column spacing or the plane perpendicular to the arrangement direction of the multiple magnetic core columns, thereby reducing the thickness of the winding along the direction of the magnetic column spacing or the arrangement direction of the multiple magnetic core columns, and further reducing the spacing between the adjacent magnetic core columns and the volume of the magnetic core.

[0030] In the second installation orientation of the coupling surface, the coupling surface can be parallel to the cross section of the magnetic core column or the plane where the secondary side winding is located, so that the winding is laid flat in the plane parallel to the winding, the thickness of the winding in the direction perpendicular to the plane is reduced, and the height of the magnetic core column (i.e. the direction perpendicular to the cross section of the magnetic core column) is reduced. Therefore, based on the installation of the coupling inductance structure on the circuit board in the second installation orientation, the size of the coupling inductance structure in the thickness direction of the circuit board is reduced, and the thickness of the single board is reduced.

[0031] The cross section of the magnetic core column mentioned in the present application can refer to the cross section parallel to the effective cross section of the magnetic core of the secondary side winding or the cross section perpendicular to the direction of the magnetic field generated by the winding in the magnetic core column.

[0032] The present application does not limit the function of the switching circuit, for example, the switching circuit can be used to adjust the phase shift angle of the drive signal output by the power supply, and / or adjust the amplitude of the drive signal. The present application does not limit the type of drive signal, for example, the drive signal can be a voltage signal or a current signal.

[0033] The present application does not limit the type of switching circuit. Optionally, the two switching circuits respectively include a first switch tube and a second switch tube, a first end of the first switch tube is connected to the input end of the switching circuit, a second end of the first switch tube is respectively connected to a first end of the second switch tube and an output end of the switching circuit, and a second end of the second switch tube is grounded.

[0034] Optionally, the VRM further includes a controller, and the controller is used to control the two switching circuits respectively. The controller is used to control the switching state of the first switch tube and the second switch tube respectively, so as to control the two switching circuits to perform different angle phase shifts on the drive signal output by the power supply and / or adjust the amplitude of the drive signal respectively.

[0035] Optionally, the VRM further includes a drive circuit, an input end of the drive circuit is connected to the controller, and an output end of the drive circuit is respectively connected to a control end of the first switch tube and a control end of the second switch tube. The drive circuit is used to control the first switch tube and the second switch tube according to the control signal output by the controller, so as to control the two switching circuits to perform different angle phase shifts on the drive signal output by the power supply and / or adjust the amplitude of the drive signal respectively.

[0036] The present application does not limit the specific structure of the magnetic core, for example, the coupling inductance can be selected from a three-column EE type magnetic core or a three-column EI type magnetic core, or the magnetic core in the coupling inductance can be obtained by slotting the middle magnetic core column of the three-column EE type magnetic core or the three-column EI type magnetic core.

[0037] In a second aspect, the present application provides a circuit module, which includes a circuit board, one or more chips integrated on the circuit board, and one or more VRMs integrated on the circuit board, the VRM can be the VRM described in the first aspect or any implementation manner of the first aspect, and the one or more VRMs are used to supply power for the one or more chips.

[0038] A single VRM can be used to supply power for a single chip, or a single VRM can be used to supply power for multiple chips, or multiple VRMs can be used to supply power for a single chip.

[0039] The output end of the VRM can be connected (or directly connected) to the power pin of the corresponding chip. The VRM can be deployed as a power supply solution around the main chip on the circuit board.

[0040] In a third aspect, the present application provides an electronic device, which includes a housing and one or more circuit modules installed inside the housing, and the circuit module can be the circuit module described in the second aspect.

[0041] The present application does not limit the type of electronic device. For example, the electronic device can be an information and communications technology (ICT) related hardware product, such as a server or an artificial intelligence (AI) inference platform device, etc.

[0042] In a fourth aspect, the present application provides a coupled inductor structure, which includes a magnetic core and a plurality of windings integrated on the magnetic core, wherein the magnetic core has three magnetic core columns, the plurality of windings includes a secondary winding and two primary windings, and when the two primary windings are negatively coupled, the two primary windings are positively coupled with the secondary winding respectively.

[0043] The coupled inductor structure provided by the present application is applied in the VRM, and the two primary windings are used as inductors in two step-down circuits, which is conducive to realizing the magnetic coupling and electrical coupling between different inductor windings in the two-phase step-down circuit. In this way, it is not only conducive to optimizing the performance of the VRM, but also conducive to reducing the volume of the magnetic core by reducing the number of magnetic core columns, and further reducing the volume of the VRM and improving the power supply efficiency of the VRM.

[0044] Optionally, the secondary winding is wound on a first magnetic core column of the three magnetic core columns; and the magnetic core effective cross-sectional area Ae of the secondary winding on the first magnetic core column is smaller than the cross-sectional area of the first magnetic core column, and / or the material of the magnetic core structure is a metal magnetic material, and / or the permeability of the material of the magnetic core structure does not exceed 100 henry / meter.

[0045] Optionally, the two primary side windings each comprise a target side, and the target sides of the two primary side windings are located in a first magnetic column gap and a second magnetic column gap respectively, wherein the first magnetic column gap is located between the second magnetic core column and the first magnetic core column of the three magnetic core columns, and the second magnetic column gap is located between the third magnetic core column and the first magnetic core column of the three magnetic core columns.

[0046] The two primary side windings each further comprise a side other than the target side, and the other side of the two primary side windings is wound on the second magnetic core column and the third magnetic core column respectively, or the two ends of the target side are the input end and the output end of the corresponding primary side winding respectively.

[0047] Optionally, the coupling inductor structure is fixed on the surface of a circuit board or buried in the circuit board, and the plurality of windings are parallel to the circuit board respectively.

[0048] Optionally, the surface of the target side opposite to the secondary side winding is parallel to the circuit board.

[0049] The details and beneficial effects of the possible implementation manners of the coupling inductor structure in the fourth aspect can be understood with reference to the related content of the first aspect, which will not be described herein again. BRIEF DESCRIPTION OF DRAWINGS

[0050] FIG. 1 schematically shows a possible circuit topology of a VRM;

[0051] FIG. 2 schematically shows a circuit topology of a VRM corresponding to solution 1;

[0052] FIG. 3 schematically shows a circuit topology of a VRM corresponding to solution 2;

[0053] FIG. 4 schematically shows a circuit topology of a VRM corresponding to solution 4;

[0054] FIGS. 5-1 to 5-3 schematically show possible structures of a coupling inductor provided by the present application respectively;

[0055] FIG. 6 schematically shows a circuit topology of a VRM provided by the present application;

[0056] FIGS. 7-1 to 7-4 schematically show application scenarios of a VRM provided by the present application respectively. DETAILED DESCRIPTION

[0057] With the evolution of chips, the area of the chip and the power supply required by the chip are more and more, the power consumption is more and more large, and the available area left for the power supply on the single board is smaller and smaller, so it is critical to improve the power supply density. The types of chips in the present application include but are not limited to central processing units (CPUs), graphics processing units (GPUs), field-programmable gate arrays (FPGAs), and neural network processing units (NPUs), etc.

[0058] In addition, the clock frequency of the chip is faster and faster, the working voltage is lower and lower, the required working current is higher and higher, and the working current is constantly dynamically adjusted as the operation service changes. For example, the working voltage of some current CPU cores has been reduced to below 1V, the working current can reach 500A to 1000A or even above, and the dynamic change rate of the working current can reach 1000A / μs or above.

[0059] In order to adapt to the above working conditions of the chip, the voltage regulation module (VRM) is generally used to supply power to the chip at present, and the VRM often adopts a multi-phase buck circuit to reduce the output voltage ripple and improve the dynamic response speed. The circuit topology of the VRM is generally as shown in FIG. 1.

[0060] In the VRM, the inductance as a passive device is a key device, which not only has a great influence on the steady-state and dynamic performance of the circuit, but also, since the inductance is generally realized by a magnetic core and a winding, the size of the inductance accounts for a large proportion in the VRM.

[0061] In order to meet the increasing dynamic requirements of chip load, the filter inductance of the VRM circuit is gradually reduced, but smaller filter inductance will cause the current ripple to rise and the efficiency to decrease. Therefore, how to reduce the current ripple while reducing the size of the inductance structure and improve the dynamic change rate of the working current has become a problem to be solved urgently.

[0062] Figure 2 schematically illustrates one solution (referred to as Solution 1). As shown in Figure 2, by integrating the windings of the inductors in the two buck circuits on the same magnetic core, a magnetic coupling is formed, resulting in a coupled inductor structure (or simply coupled inductor). Replacing the discrete inductors in the VRM with the coupled inductor (i.e., a single winding wound on a single magnetic core) not only helps to reduce the volume occupied by the inductors in the multi-phase buck circuit, thereby reducing the volume occupied by the VRM on a single board, but also helps to improve the transient performance while ensuring the same steady-state ripple. In this context, magnetic coupling can refer to the physical phenomenon in which different current-carrying coils (or windings) are linked by each other's magnetic fields. In a VRM, the inductor windings of a multi-phase buck circuit are wound in various forms on the same magnetic core, thereby being coupled to each other in the magnetic circuit.

[0063] However, for a magnetically coupled VRM, when the coupling coefficient is small, the steady-state and dynamic inductance changes are not large, and the performance index optimization is not obvious. Only when the coupling coefficient is large, i.e., the coupling between the two phases is strong, the steady-state and dynamic improvement effect is relatively obvious. However, an increase in the coupling coefficient means an increase in the coupling between the two phases, and the mutual influence between the two phases increases, which increases the difficulty of control. Moreover, when there are multiple phases, the process consistency becomes worse. Meanwhile, in the case of ensuring the same steady-state inductance, the range of adjustment of the coupling coefficient is limited, and the range of adjustment of the transient inductance is also limited.

[0064] Figure 3 schematically illustrates the circuit topology of a trans-inductor voltage regulator (TLVR), which is another solution (referred to as Solution 2) to the above-mentioned problem. As shown in Figure 3, the windings of the inductors of the multi-phase buck circuit serve as the primary winding of a transformer, and the inductors of different buck circuits are indirectly coupled through the secondary winding of the transformer, thereby achieving the coordinated work between the phases in a traditional multi-phase interleaved buck circuit and improving the transient response of the circuit. When the primary current of one phase in the circuit changes, the currents of the other phases also change through the coupling of the secondary winding of the transformer, thereby greatly improving the change speed of the total output current I L In this application, the windings can also be referred to as coils. Electrical coupling can refer to the direct connection between different parts of a circuit through a wire, thereby coordinating the work. In this application, it can refer to the series connection of the secondary winding of the transformer in the VRM (or TLVR), thereby linking the buck circuits of the VRM shown in Figure 1 and coordinating the work, so that the current of one phase changes and the current of the other phase changes.

[0065] But TLVR changes the inductance of VRM to transformer, not only needs to add a secondary inductance (e.g. Li0, i is a positive integer less than or equal to n) for each inductance of VRM to realize corresponding coupling (e.g. Mi0), but also needs to add an inductance L in series with the secondary inductance c These factors make the loss and volume of TLVR larger than traditional multiphase interleaved buck circuit.

[0066] In order to reduce the volume of TLVR, the structure of transformer in TLVR can be improved (referred to as solution 3). In the improved transformer, the magnetic core has three magnetic core columns, and the primary winding and the secondary winding are wound on the middle magnetic core column (or middle column magnetic core). However, the middle column magnetic core is divided into two parts, and the primary winding or the secondary winding only winds around one part of the middle column magnetic core, so that part of the magnetic flux of the primary winding or the secondary winding is not coupled with other windings, forming leakage inductance, and the leakage inductance in each buck circuit can be equivalent to the inductance L in series with the secondary inductance introduced in the foregoing c (or the coupling inductance of TLVR secondary side or secondary coupling inductance L c ). This structure can realize even if the number of turns is only 1, but the turn ratio can be flexibly set. Through this kind of magnetic core structure, the leakage inductance of TLVR transformer can be quantitatively controlled, which is equivalent to dispersing the secondary coupling inductance L c into each transformer, thereby facilitating to avoid installing the secondary coupling inductance L c outside each transformer (or coupling inductance), thereby facilitating to reduce the volume and loss of the whole magnetic component in TLVR.

[0067] However, this method causes the magnetic core structure to be relatively complex, and the processing precision of the middle column magnetic core is relatively high, and the manufacturing consistency is challenging. Moreover, using this magnetic core only eliminates the secondary coupling inductance L c , and cannot reduce the volume of the original transformer, and the overall volume reduction is limited.

[0068] Considering the advantages of the magnetic coupled VRM combined with solution 1 and the electric coupled VRM (i.e. TLVR) combined with solution 2, that is, not only can the magnetic component volume be reduced through magnetic coupling, but also it is beneficial to improve the transient performance and reduce the loss under the condition of ensuring the same steady-state ripple. Therefore, how to design a TLVR combined with magnetic coupling and electric coupling hybrid coupling is of great significance for improving the dynamic characteristics, reducing the volume and improving the efficiency of the traditional interleaved buck circuit.

[0069] Figure 4 schematically shows a structure of a hybrid coupled inductor used in solution 4, which can form magnetic coupling and electrical coupling. As shown in Figure 4, the coupled inductor used in solution 4 changes the three-column EE-type magnetic core used in solution 3 into a five-column EI-type magnetic core, and winds two primary windings (i.e., windings of the inductor in the buck circuit) and one secondary winding on the middle three magnetic core columns, respectively. Among the middle three magnetic core columns, the two outer magnetic core columns are used to wind the primary windings of the two buck circuits of the TLVR, and the middle magnetic core column is used to wind the secondary winding of the TLVR. The primary-secondary coupling coefficient and leakage inductance can be adjusted by adjusting the air gap of each magnetic core column and the width of the two outer side columns (i.e., magnetic core columns without winding). The secondary windings of all the magnetic components (i.e., windings of the inductor in the buck circuit) are connected in series to form the secondary winding of the TLVR. This structure realizes the integration of the inductors of the two-phase buck circuit and the secondary inductor Lc, forms magnetic coupling and electrical coupling, has high integration, and reduces the volume.

[0070] However, in order to adjust the coupling coefficient, the five magnetic core columns may need different air gap lengths, which is difficult to control in actual processing and has high processing difficulty. When a high primary-secondary coupling coefficient is required, the magnetic flux of the two outer columns (i.e., magnetic core columns without winding) is small, and the thickness of the outer columns may be very thin, further increasing the processing difficulty. Moreover, the outer columns are easily damaged, reducing the reliability of the TLVR.

[0071] In order to further reduce the volume of the magnetic components in the VRM, the present application provides a coupled inductor, which integrates two primary windings and one secondary winding on a three-column magnetic core. When the two primary windings of the coupled inductor are used as the inductors of the two-phase buck circuit in the VRM, the advantages of the two-phase magnetically coupled VRM and the electrically coupled TLVR can be combined to realize magnetic-electric hybrid coupling. In this way, the volume of the magnetic core is reduced, the circuit efficiency is improved, and the transient response performance of the circuit is greatly improved.

[0072] The structure of the coupled inductor provided by the present application will be described below in conjunction with the accompanying drawings.

[0073] Figure 5-1 schematically shows a possible schematic diagram of a coupled inductor mounted on a circuit board. As shown in Figure 5-1, the coupled inductor includes three windings, namely primary winding 1, primary winding 2, and secondary winding. In the coupled inductor structure shown in Figure 5-1, the parts other than the three windings are magnetic cores, wherein the magnetic cores include two cover plates and three magnetic core columns between the two cover plates, which are denoted as magnetic core column 1 to magnetic core column 3.

[0074] As shown in FIG. 5-1, the cross-sectional area of the magnetic core column is the area of the cross-section of the magnetic core column in the x-z plane. The primary winding 1 and the primary winding 2 are wound on the magnetic core column 2 and the magnetic core column 3 respectively, the magnetic core column 1 has a groove opened along the x-y plane, and the secondary winding is installed in the gap between the groove and the different magnetic core column, or in other words, the secondary winding is wound on a part of the cross-section of the magnetic core column 1. As shown in FIG. 5-1, the cross-sectional area of the magnetic core column is divided into cross-section 1 and cross-section 2 by the groove, wherein the magnetic core effective cross-sectional area Ae of the secondary winding on the magnetic core column 1 is the area of the cross-section 1, which is smaller than the cross-sectional area of the first magnetic core column. Since the magnetic flux of the primary winding in the magnetic core column 1 includes the magnetic flux flowing through the cross-section 1 and the magnetic flux flowing through the cross-section 2, it is beneficial to increase the leakage inductance of the primary winding 1 and the primary winding 2. The coupling inductor shown in FIG. 5-1 can be understood as using the first implementation manner of increasing leakage inductance introduced in the foregoing. Alternatively, in order to further increase the leakage inductance, the coupling inductor shown in FIG. 5-1 can also use the second implementation manner of increasing leakage inductance introduced in the foregoing, that is, the magnetic core is made of a material with relatively low permeability, for example, the material of the magnetic core structure is a metal magnetic material, and / or the permeability of the material of the magnetic core structure is not more than 100 henry / meter. The present application does not limit the type of metal magnetic material, for example, the metal magnetic material can include iron and / or nickel, etc.

[0075] The target side of the primary winding 1 introduced in the foregoing can be understood as the winding part of the primary winding 1 between the magnetic core column 1 and the magnetic core column 2 in FIG. 5-1, the target side of the primary winding 2 can be understood as the winding part of the primary winding 2 between the magnetic core column 1 and the magnetic core column 3 in FIG. 5-1, and the other sides of the primary winding 1 and the primary winding 2 can be understood as the other winding parts of the corresponding primary winding except the target side in FIG. 5-1. Therefore, the coupling inductor shown in FIG. 5-1 can be understood as using the first installation manner of the primary winding introduced in the foregoing. Alternatively, the coupling inductor shown in FIG. 5-1 can also use the second installation manner of the primary winding introduced in the foregoing.

[0076] The first side of the secondary winding can be understood as the part of the secondary winding between the magnetic core column 1 and the magnetic core column 2 in Fig. 5-1, and the second side of the secondary winding can be understood as the part of the secondary winding between the magnetic core column 1 and the magnetic core column 3 in Fig. 5-1. As shown in Fig. 5-1, the target side of the primary winding 1 is parallel to the y-z plane, i.e., perpendicular to the cross section of the magnetic core column or the plane where the secondary winding is located, with respect to the surface (i.e., the first coupling surface introduced above) on the first side of the secondary winding, and the target side of the primary winding 2 is parallel to the y-z plane, i.e., perpendicular to the cross section of the magnetic core column or the plane where the secondary winding is located, with respect to the surface (i.e., the second coupling surface introduced above) on the second side of the secondary winding. Therefore, the coupling inductor shown in Fig. 5-1 can be understood as using the first deployment orientation of the coupling surface introduced above. In this way, it is beneficial to lay the windings in the plane perpendicular to the distance between the magnetic columns or the plane perpendicular to the arrangement direction of the plurality of magnetic core columns (i.e., the y-z plane), thereby facilitating the reduction of the thickness of the windings in the direction of the distance between the magnetic columns or the arrangement direction of the plurality of magnetic core columns (i.e., in the x direction), and further reducing the distance between the adjacent magnetic core columns (e.g., the distance between the magnetic core column 1 and the magnetic core column 2 and / or the distance between the magnetic core column 1 and the magnetic core column 3) to reduce the volume of the magnetic core. Alternatively, the coupling inductor shown in Fig. 5-1 can also use the second deployment orientation of the coupling surface introduced above.

[0077] As shown in Fig. 5-1, the three windings are perpendicular to the x-y plane, i.e., perpendicular to the surface of the circuit board. Therefore, the coupling inductor shown in Fig. 5-1 can be understood as using the first mounting method introduced above. Alternatively, the coupling inductor shown in Fig. 5-1 can also use the first mounting method introduced above.

[0078] Fig. 5-2 schematically shows another possible schematic diagram of a coupling inductor mounted on a circuit board. Like the coupling inductor shown in Fig. 5-1, the coupling inductor shown in Fig. 5-2 includes a three-column magnetic core and three windings, uses the first mounting method of the primary winding, the first deployment orientation of the coupling surface, and the first mounting method on the circuit board introduced above. Unlike the coupling inductor shown in Fig. 5-1, the effective cross-sectional area Ae of the magnetic core of the secondary winding on the magnetic core column 1 in the coupling inductor shown in Fig. 5-2 is equal to the cross-sectional area of the first magnetic core column.

[0079] Optionally, to increase the leakage inductance, the coupling inductor shown in Fig. 5-2 can use the second implementation of increasing the leakage inductance introduced above, i.e. to select a material with lower permeability to make the magnetic core, for example, the material of the magnetic core structure is a metallic magnetic material, and / or the permeability of the material of the magnetic core structure is not more than 100 henry / meter. Since the permeability of the material of the magnetic core is lower, the leakage magnetic flux (or the leaked magnetic flux) of the primary winding in the surrounding environment outside the magnetic core increases, and this part of the leakage magnetic flux is sufficient to form a large enough leakage inductance, so that the circuit achieves appropriate transient and steady-state performance. Moreover, the magnetic core material is selected to be a material with lower permeability (for example, a magnetic powder core material), and the leakage inductance is constructed by the leakage magnetic flux in the surrounding environment outside the magnetic core, so that the secondary winding can completely surround the center column, and the structure of the magnetic core and the winding is greatly simplified, for example, the magnetic core can use a conventional three-column EE magnetic core or a three-column EI magnetic core, which greatly reduces the processing difficulty, improves the process consistency, is convenient to process and use, and realizes mass production.

[0080] Optionally, the coupling inductor shown in Fig. 5-2 can also use the second mounting method of the primary winding introduced above, and / or use the second deployment orientation of the coupling surface and the second mounting method on the circuit board.

[0081] Fig. 5-3 schematically shows another possible schematic diagram of a coupling inductor mounted on a circuit board. As shown in Fig. 5-3, the coupling inductor includes three windings, namely a primary winding 1, a primary winding 2 and a secondary winding, and the part or region of the coupling inductor other than the windings represents a magnetic core. The region of the magnetic core located between the two primary windings corresponds to the magnetic core column 1 shown in Figs. 5-1 and 5-2, the region of the magnetic core located in the -x direction (i.e. the direction opposite to the x direction) of the primary winding 1 corresponds to the magnetic core column 2 shown in Figs. 5-1 and 5-2, the region of the magnetic core located in the x direction of the primary winding 2 corresponds to the magnetic core column 3 shown in Figs. 5-1 and 5-2, and the cross section of the magnetic core column or the plane where the secondary winding is located is located in the x-y plane. Therefore, like the coupling inductor shown in Fig. 5-1, the coupling inductor shown in Fig. 5-3 includes a three-column magnetic core and three windings, and uses the first implementation of increasing the leakage inductance introduced above, i.e. the secondary winding is wound around part of the cross section of the magnetic core column between the two primary windings. Optionally, to further increase the leakage inductance, the coupling inductor shown in Fig. 5-3 can also use the second implementation of increasing the leakage inductance introduced above, i.e. to select a material with lower permeability to make the magnetic core, for example, the material of the magnetic core structure is a metallic magnetic material, and / or the permeability of the material of the magnetic core structure is not more than 100 henry / meter. Optionally, in the coupling inductor shown in Fig. 5-3, the secondary winding can also be wound around the entire cross section of the magnetic core column between the two primary windings.

[0082] Different from the coupling inductors shown in FIG. 5-1 and FIG. 5-2, in the coupling inductor shown in FIG. 5-3, the two primary windings are respectively located between two adjacent magnetic core columns, or in other words, the two primary windings are target sides, and do not include other sides introduced above, or in other words, the two ends of the target side are the input end and the output end of the primary winding. Therefore, the coupling inductor shown in FIG. 5-3 can be understood as using the second mounting mode of the primary winding introduced above. In this way, it is beneficial to shorten the length of the primary winding while ensuring the coupling coefficient of the primary winding and the secondary winding, thereby reducing the loss of the driving signal output by the power supply in the primary winding, and further improving the power supply efficiency of the VRM to the load. The coupling inductor shown in FIG. 5-3 can also use the first mounting mode of the primary winding introduced above, that is, the primary winding also includes other sides wound on the outer magnetic core column. As shown in FIG. 5-3, the current I1 in the primary winding 1 and the current I2 in the primary winding 2 are opposite in direction, and the secondary winding is U-shaped and placed above the primary winding, thereby forming a positive coupling structure with the two primary windings. In this way, the coupling inductor structure can maximize the use of the core area.

[0083] Different from the coupling inductors shown in FIG. 5-1 and FIG. 5-2, in the coupling inductor shown in FIG. 5-3, the plurality of windings are respectively parallel to the x-y plane, that is, parallel to the surface of the circuit board, or in other words, the extension direction of the winding in the coupling inductor structure is parallel to the surface of the circuit board. Therefore, the coupling inductor shown in FIG. 5-3 can be understood as using the second mounting mode of the coupling inductor introduced above. In this way, even if the input end and the output end of the winding are on different surfaces of the coupling inductor structure, for example, the input end and the output end of the primary winding 1 and the primary winding 2 are respectively located on the surface of the coupling inductor facing the y direction and the surface facing the -y direction (that is, the direction opposite to the y direction), it is still beneficial to ensure that the input end and the output end of the winding have the same height relative to the circuit board, thereby facilitating the shortening of the lead length between the input end and the output end of the winding and the PCB, reducing the loss of the driving signal output by the power supply in the primary winding, and further improving the power supply efficiency of the VRM to the load. In addition, the plurality of windings are respectively parallel to the circuit board, which is also beneficial to bury the coupling inductor structure in the circuit board and use the traces in the circuit board as windings, thereby further reducing the height of the VRM in the single board. For example, the magnetic core is used to construct the coupling inductor structure shown in FIG. 5-3 in a buried form, and then the magnetic core is subjected to layering and interconnection through the PCB process.

[0084] The coupling inductance shown in FIG. 5-3 is different from the coupling inductance shown in FIG. 5-1 and FIG. 5-2. In the coupling inductance shown in FIG. 5-3, the surface (i.e., the first coupling surface) on the target side of the primary winding 1 and the first side of the secondary winding that is oppositely arranged (or closest to) and the surface (i.e., the second coupling surface) on the target side of the primary winding 2 and the second side of the secondary winding that is oppositely arranged (or closest to) are respectively parallel to the x-y plane, that is, the first coupling surface and the second coupling surface are respectively parallel to the cross section of the magnetic core column or the plane where the secondary winding is located. In this way, it is beneficial to lay the windings in the plane parallel to the windings (such as the x-y plane), thereby reducing the thickness of the windings in the direction perpendicular to the plane (such as the z direction), and thus it is beneficial to reduce the height of the magnetic core column (i.e., the direction perpendicular to the cross section thereof, such as the z direction). In this way, as shown in FIG. 5-3, based on mounting the coupling inductance structure on the circuit board according to the second mounting manner, it is beneficial to reduce the size of the coupling inductance structure in the thickness direction of the circuit board (i.e., the z direction), thereby facilitating the reduction of the thickness of the single board. Alternatively, the coupling inductance shown in FIG. 5-3 can also be mounted on the circuit board using the first mounting manner of the coupling inductance introduced above.

[0085] The present application does not limit the relative size relationship between the cross-sectional areas of the three magnetic core columns. For example, the cross-sectional area of the magnetic core column 2 and the cross-sectional area of the magnetic core column 3 can be the same. For example, the cross-sectional area of the magnetic core column 1 can be greater than the cross-sectional area of the magnetic core column 2 and the cross-sectional area of the magnetic core column 3, respectively. Alternatively, the cross-sectional area of the magnetic core column 1 can be 1.5 times or 2 times the cross-sectional area of the magnetic core column 2, and similarly, the cross-sectional area of the magnetic core column 1 can be 1.5 times or 2 times the cross-sectional area of the magnetic core column 3. Alternatively, the cross-sectional area of the magnetic core column 1 can be equal to the cross-sectional area of the magnetic core column 2, and the cross-sectional area of the magnetic core column 1 can be equal to the cross-sectional area of the magnetic core column 3.

[0086] The above takes the magnetic core made of a material with a relatively low magnetic permeability as an example. Since the material with a relatively low magnetic permeability has a relatively high saturation magnetic flux density, it is beneficial to reduce the volume of the magnetic core and is suitable for application scenarios with strong demands for volume and height. In order to be suitable for application scenarios with strong demands for efficiency, the coupling inductance structure can also use a material such as ferrite with high magnetic permeability and low loss to make the magnetic core.

[0087] FIGS. 5-1 to 5-3 take the three magnetic core columns as an example, which are located in the same plane, or in other words, the three magnetic core columns are arranged in the x direction in sequence. Correspondingly, the magnetic core column 1 can be referred to as the middle magnetic core column, and the magnetic core column 2 and the magnetic core column 3 can be referred to as the outer magnetic core columns. Alternatively, the three magnetic core columns can not be located in the same plane.

[0088] As shown in FIGS. 5-1 to 5-3, the coupling inductor provided in the present application integrates two primary windings and one secondary winding on a three-column magnetic core. When the two primary windings of the coupling inductor are used as the inductors of the two-phase buck circuit in the VRM, not only is it conducive to achieving the magnetic coupling between the inductors of the two-phase buck circuit achieved by solution 1, but also the electrical coupling between the two-phase buck circuits achieved by solution 2 is achieved through the secondary winding of the coupling inductor, thereby facilitating the realization of magnetic-electric hybrid coupling, and compared with solution 1 and solution 2, it is conducive to more significantly improving the transient response performance of the circuit and improving the efficiency of the circuit. Moreover, compared with solution 2, since the number of secondary windings is reduced, for example, the number of secondary windings is reduced by half, not only is it conducive to reducing the volume of the magnetic core, thereby reducing the layout space occupied by the VRM on the single board, but also it is conducive to reducing the loss of induced current on the secondary winding and improving the electrical energy conversion efficiency of the VRM.

[0089] Different application scenarios can have different demands for indicators, and different implementation modes of the coupling inductor introduced in the foregoing can be combined in any manner to adapt to various application scenarios.

[0090] The coupling inductor can be a discrete inductor, which can be fixed on the surface of the circuit board. Alternatively, in some examples, the coupling inductor can be embedded inside the circuit board and can be processed during the processing of the circuit board.

[0091] The present application does not limit the shape or form of the magnetic core material. For example, the magnetic core can be made of one or more forms of magnetic core material, including at least one of paste, film, and powder. The present application does not limit the manufacturing method of the winding. For example, the winding can be an enameled flat wire or a PCB winding, etc.

[0092] The three windings of the coupling inductor provided in the present application are wound on different three magnetic core columns, and compared with solution 3 introduced in the foregoing, by avoiding winding different windings on the same magnetic core column, it is conducive to reducing the requirement for the processing precision of the magnetic core.

[0093] The coupling inductor provided by the application can increase the leakage inductance of the primary winding in the three-column magnetic core by using the first leakage inductance increasing implementation and / or the second leakage inductance increasing implementation, which is conducive to avoiding the additional series connection of Lc for the secondary winding in the VRM, thereby reducing the physical size of the VRM and improving the integration of the circuit board. Compared with solution 4, the number of magnetic core columns in the magnetic core is reduced, which is conducive to reducing the size of the coupling inductor structure, reducing the number of air gaps that need to be processed, and reducing the processing difficulty. In terms of the magnetic core structure, two outer columns of the magnetic core shown in FIG. 4 are removed, and the secondary winding is wound on a part of the cross section of the middle magnetic core column (or middle column). This can be basically regarded as converting the two outer columns of the magnetic core corresponding to solution 4 into the part of the middle column that is not surrounded by the secondary winding (for example, S2 shown in FIG. 5-1). In this way, on the one hand, under the same coupling coefficient, according to the first leakage inductance increasing implementation, the cross-sectional area of the part of the middle column that is not surrounded by the secondary winding (that is, S2) is larger than the cross-sectional area of the single magnetic core outer column shown in FIG. 4, which is easier to process. On the other hand, according to the first leakage inductance increasing implementation, the coupling coefficient is adjusted by adjusting the cross-sectional area of the middle column surrounded by the secondary winding, without changing the size of the air gap between the magnetic core column and the cover plate. Therefore, the air gap sizes between different magnetic core columns and the cover plate can be the same, which reduces the processing difficulty and increases the processing feasibility.

[0094] The foregoing describes the structure of the coupling inductor provided by the application. The following describes a VRM that applies the coupling inductor.

[0095] FIG. 6 schematically shows the circuit topology of a VRM that applies the coupling inductor provided by the application. As shown in FIG. 6, the VRM can include n-phase buck circuits, where n is a positive integer greater than 1. The input end of each buck circuit is connected to a power supply, and the output end is connected to a chip. The current input to the chip by the n-phase buck circuits is I L The chip can be replaced by other types of loads as needed. Each buck circuit includes a switching circuit and a filter circuit. The filter circuit includes a capacitor and an inductor. The switching circuit of the buck circuit i includes switches Ki_1 and Ki_2, where i is a positive integer less than or equal to n. The two switches are in half-bridge connection, the top and bottom of the half-bridge are respectively connected to the input voltage of the power supply and the ground, the middle of the bridge arm of the half-bridge is connected to the first end of the inductor, the second end of the inductor is respectively connected to one end of the output capacitor C and the power supply pin of the chip, and the other end of the capacitor is connected to the ground.

[0096] Taking an even number n as an example, the VRM can further include n / 2 series-connected inductors (referred to as secondary inductors Lc). The n / 2 series-connected inductors can be connected at both ends to the ground. Moreover, the inductor in each buck circuit and one secondary inductor correspond to one coupling inductor provided by the application. Accordingly, the VRM includes n / 2 coupling inductors.

[0097] Alternatively, it can be considered that the VRM includes n / 2 circuit units, and one of the circuit units in the VRM is identified by a dashed box in FIG. 6, which will be introduced below. As shown in FIG. 6, the circuit unit includes a coupled inductor, which can be any coupled inductor provided in the present application, such as the coupled inductor shown in any one of FIGS. 5-1 to 5-3. In FIG. 6, Np1 and Np2 can represent two primary windings in the coupled inductor, respectively, Ns can represent a secondary winding in the coupled inductor, M10 can represent a coupling between the primary winding Np1 and the secondary winding Ns, M20 can represent a coupling between the primary winding Np2 and the secondary winding Ns, and M can represent a coupling between the primary winding Np1 and the primary winding Np2.

[0098] As shown in FIG. 6, the circuit unit further includes two switch circuits, and outputs of the two switch circuits are connected to inputs of the primary windings Np1 and Np2, respectively. Among them, the switch circuit connected to the primary winding Np1 includes switches K1_1 and K1_2 in half-bridge connection, and the switch circuit connected to the primary winding Np2 includes switches K2_1 and K2_2 in half-bridge connection, the input of the switch circuit is the top of the half-bridge, and the output of the switch circuit is the bridge arm of the half-bridge.

[0099] As shown in FIG. 6, the output of the primary winding Np1 and the output of the primary winding Np2 are connected to the output capacitor C and the chip, respectively. Optionally, it can be considered that the circuit unit further includes the capacitor C or a part of the capacitor C.

[0100] The VRM further includes a controller configured to control switching states of the switches in the switch circuits. The present application does not limit the types of the switches in the VRM, for example, the switches can be Insulated Gate Bipolar Transistors (IGBTs), Metal Oxide Semiconductor Filed Effect Transistors (MOSFETs, referred to as MOS tubes) or Silicon Carbide Metal Oxide Semiconductor (SiC MOSFETs), etc.

[0101] The controller of the embodiments of the present application is an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), a Digital Signal Processor (DSP), or a combination thereof. The PLD can be a Complex Programmable Logic Device (CPLD), a Field-programmable Gate Array (FPGA), a Generic Array Logic (GAL), or any combination thereof, which is not limited in the embodiments of the present application.

[0102] The controller can control the phase shift angle and / or the amplitude of the driving signal input to Np1 by controlling the switching state of switch K1_1 and switch K1_2 respectively. In an example, the controller can control the driving signals input to the primary windings of different buck circuits to have different phase shift angles. For example, the phase shift angle of the driving signal of the i-th phase buck circuit is (i*360° / n). Alternatively, the phase shift angles of the driving signals input to two primary windings belonging to the same circuit unit or corresponding to the same coupled inductor are different by or staggered by 180°. As an example, assuming that n is 8, in FIG. 6, the buck circuit with current I1 can be the first phase buck circuit, the buck circuit with current I2 can be the fifth phase buck circuit, the buck circuit with current In-1 can be the fourth phase buck circuit, and the buck circuit with current In can be the eighth phase buck circuit.

[0103] In the same coupled inductor of the VRM shown in FIG. 6, a negative coupling can be formed between Np1 and Np2, a positive coupling can be formed between Np1 and Ns, and a positive coupling can be formed between Np2 and Ns, which is beneficial to reduce current ripple and improve dynamic response.

[0104] In addition, by using the first implementation manner of increasing leakage inductance and / or the second implementation manner of increasing leakage inductance in the coupled inductor, the leakage inductance of Np1 and Np2 can be increased, so that, as shown in FIG. 6, it is beneficial to avoid adding other inductors in the series circuit of Ns in addition to the coupled inductor.

[0105] In the coupled inductor shown in FIG. 5-1 and FIG. 5-3, the secondary winding N s The ratio between the cross-sectional area surrounding the core column 1 and the total cross-sectional area of the core column 1 can be adjusted to adjust the coupling coefficient of the primary winding and the secondary winding or to adjust the leakage inductance of the primary winding, and further to adjust the steady-state characteristics and transient characteristics of the VRM. When the secondary winding N sThe larger the cross-sectional area of the magnetic core column 1 surrounded by the secondary winding Ns, the larger the primary-secondary coupling coefficient, the smaller the leakage inductance, and thus the stronger the electrical coupling between the primary windings of the two-phase buck circuit in the VRM, the larger the steady-state ripple of the corresponding circuit, and the stronger the transient response characteristics. Conversely, the smaller the cross-sectional area of the magnetic core column 1 surrounded by the secondary winding Ns, the smaller the primary-secondary coupling coefficient, the larger the leakage inductance, and thus the weaker the electrical coupling between the primary windings of the two-phase buck circuit in the VRM, the smaller the steady-state ripple of the corresponding circuit, and the weaker the transient response characteristics. When the secondary winding Ns does not surround the magnetic core column 1 at all, the primary-secondary coupling coefficient is approximately equal to 0, at which time the VRM is equivalent to a two-phase magnetic coupled VRM, and the circuit topology at this time can refer to FIG. 2.

[0106] In the above, taking the coupled inductor with three windings as an example, in some examples, based on the same concept, a larger number of windings can be integrated in the coupled inductor as needed, and the number of magnetic core columns can also be increased accordingly, for example, to form a three-phase coupled inductor, and accordingly, a single circuit unit of the VRM can include more elements in the buck circuit.

[0107] The application does not limit the application scenarios of the VRM. For example, the VRM can be integrated with one or more chips on a circuit board to power the one or more chips, or multiple VRMs can power one chip. The output end of the VRM can be connected (or directly connected) to the power pin of the corresponding chip. The VRM can be deployed around the chip on the circuit board as a power supply solution. The VRM provided in the application can be applied to chip power supply scenarios with low voltage and large current, and is particularly suitable for chip power supply scenarios with high power density requirements and high chip current dynamics.

[0108] The circuit board integrated with the VRM and the chip (referred to as a circuit module) can be installed in an electronic device. One or more circuit modules can be installed inside the shell of the electronic device. The application does not limit the type of electronic device. For example, the electronic device can be an ICT-related hardware product, such as a server or a data center device or an artificial intelligence (AI) inference platform device, etc.

[0109] Currently, there are two kinds of bus voltage, 12V and 48V, for the rack power supply system in data center. The 12V bus voltage architecture in FIG. 7-1 is a traditional power supply system. In the figure, AC / DC is used to convert alternating current (AC) to direct current (DC), DC / AC is used to convert DC to AC, and DC / DC is used to convert DC to DC, such as converting a fixed DC voltage to a variable DC voltage. As shown in FIG. 7-1, a server rack can include AC / DC, DC / DC, multiple VRMs, and multiple chips. Among them, AC / DC and DC / DC are used to convert AC input by an uninterruptible power system (UPS) into 12V DC, and multiple voltage regulators (VRs) are used to convert the 12V bus voltage into a low voltage that meets the requirements of the connected chips, respectively. In FIG. 7-1, different VRs can be integrated on the same or different circuit boards. FIG. 7-1 takes the chips connected by the VRs as CPU, memory, and chipset as examples, but the type of chips connected by the VRs is not limited, and the number of VRMs in the server rack is also not limited. The VRM provided by the present application can be applied to at least one VR.

[0110] The rack power supply in FIG. 7-2 raises the bus voltage from 12V to 48V, and the large online uninterruptible power supply (UPS) is replaced by a local compact DC 48V UPS close to the load side. This makes it possible to improve overall efficiency by reducing bus copper loss (increasing bus voltage and reducing current) and reducing the number of power conversion stages. The 48V power supply VR circuit is divided into two-stage (as shown in FIG. 7-3) and single-stage (as shown in FIG. 7-4) structures. As shown in FIG. 7-4, the single-stage VR is used to convert a voltage of 40V-60V to a voltage of 0.8V-1.8V. As shown in FIG. 7-4, the two-stage VR structure first uses an intermediate bus converter IBC to convert 48V to a voltage of 5-12V, and then uses a one-stage step-down to 0.8-1.8V. The first stage (or first stage) VR mainly realizes large step-down, and the second stage (or second stage) VR mainly meets the requirements of low voltage, large current, and high dynamic response characteristics of the load chip, and has the advantage of flexible structure. However, regardless of the bus voltage, the latter stage is based on the architecture of the voltage regulator VR, that is, the chips of the server are powered by VR.

[0111] The VRM provided by the application can be directly used as the VR part of the 12V bus voltage structure, and can also be used as the rear part of the two-stage structure VR corresponding to the 48V bus voltage architecture (for example, 3.3V-VR and / or 5V-VR). The application can also be used in other application scenarios, multi-phase step-down converters of other power, voltage levels, etc., to improve the circuit transient performance and reduce the circuit size.

[0112] The terms “first”, “second”, etc. in the description of the application are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. It should be understood that in the present application, “at least one” means one or more, and “multiple” means two or more. “And / or” is used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, “A and / or B” can represent: only A, only B, and A and B exist at the same time, wherein A and B can be singular or plural. The character “ / ” generally represents that the associated objects before and after are in an “or” relationship. “At least one of the following” or the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b or c can represent: a, b, c, “a and b”, “a and c”, “b and c”, or “a and b and c”, wherein a, b, and c can be single or multiple.

[0113] The above-described and above-mentioned embodiments are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the application.

Claims

1. A voltage regulator, characterized by, The voltage regulator comprises a capacitor and at least one circuit unit, the circuit unit comprising a coupled inductor structure and two switching circuits; The coupled inductor structure comprises a magnetic core and a plurality of windings integrated on the magnetic core, wherein the magnetic core has three magnetic core columns, the plurality of windings comprises a secondary winding and two primary windings, and the plurality of windings are wound on different magnetic core columns respectively. The input terminals of the two switching circuits are respectively connected to power supplies, the output terminals of the two switching circuits are respectively connected to the input terminals of the two primary windings, the output terminals of the two primary windings are respectively connected to the capacitor, and the output terminals of the two primary windings are respectively connected to loads.

2. The voltage regulator of claim 1, wherein, The secondary winding is wound on a first magnetic core column of the three magnetic core columns; and a core effective cross-sectional area Ae of the secondary winding on the first magnetic core column is smaller than a cross-sectional area of the first magnetic core column, and / or a material of the magnetic core structure is a metallic magnetic material, and / or a permeability of the material of the magnetic core structure is not more than 100 henries per meter.

3. The voltage regulator according to claim 1 or 2, characterized in that, The two primary windings respectively comprise target edges, and the target edges of the two primary windings are respectively located in a first magnetic column gap and a second magnetic column gap, wherein the first magnetic column gap is located between a second magnetic core column and the first magnetic core column of the three magnetic core columns, and the second magnetic column gap is located between a third magnetic core column and the first magnetic core column of the three magnetic core columns. The two primary windings respectively further comprise edges other than the target edges, and the other edges of the two primary windings are respectively wound on the second magnetic core column and the third magnetic core column, or two ends of the target edges are respectively input terminals and output terminals of the corresponding primary windings.

4. The voltage regulator of claim 3, wherein, The coupled inductor structure is used to be fixed on a surface of a circuit board or embedded in the circuit board, and the plurality of windings are respectively parallel to the circuit board.

5. The voltage regulator of claim 4, wherein, A surface of the target edge opposite to the secondary winding is parallel to the circuit board.

6. The voltage regulator of any one of claims 1-5, wherein, The two switching circuits respectively comprise first switching tubes and second switching tubes. A first end of the first switching tube is connected to the input terminal of the switching circuit, a second end of the first switching tube is respectively connected to a first end of the second switching tube and an output terminal of the switching circuit, and a second end of the second switching tube is grounded.

7. The voltage regulator of any one of claims 1-6, wherein, The voltage regulator further comprises a controller for controlling the two switching circuits respectively.

8. A circuit module, characterized by The circuit module comprises a circuit board, one or more chips integrated on the circuit board, and one or more voltage regulators according to any one of claims 1-7 integrated on the circuit board, and the one or more voltage regulators are used to supply power to the one or more chips.

9. An electronic device, comprising: The electronic device comprises a housing and one or more circuit modules according to claim 8 installed inside the housing.

10. A coupled inductance structure, characterized by, The coupled inductor structure comprises a magnetic core and a plurality of windings integrated on the magnetic core, wherein the magnetic core has three magnetic core columns, the plurality of windings comprises a secondary winding and two primary windings, and the plurality of windings are wound on different magnetic core columns respectively.

11. The coupled inductor structure of claim 10, wherein, The secondary winding is wound on a first magnetic core column of the three magnetic core columns; and a magnetic core effective cross-sectional area Ae of the secondary winding on the first magnetic core column is smaller than a cross-sectional area of the first magnetic core column, and / or a material of the magnetic core structure is a metallic magnetic material, and / or a permeability of the material of the magnetic core structure is not more than 100 henry / meter.

12. The coupled inductor structure of claim 10 or 11, wherein, The two primary windings each include a target side, and the target sides of the two primary windings are located in a first magnetic column gap and a second magnetic column gap respectively, wherein the first magnetic column gap is located between a second magnetic core column and the first magnetic core column of the three magnetic core columns, and the second magnetic column gap is located between a third magnetic core column and the first magnetic core column of the three magnetic core columns. The two primary windings each further include a side other than the target side, and the other sides of the two primary windings are wound on the second magnetic core column and the third magnetic core column respectively, or two ends of the target side are an input end and an output end of the corresponding primary winding respectively.

13. The coupled inductor structure of claim 12, wherein, The coupling inductance structure is used to be fixed on a surface of a circuit board or buried in the circuit board, and the plurality of windings are parallel to the circuit board respectively.

14. The coupled inductor structure of claim 13, wherein, A surface of the target side opposite to the secondary winding is parallel to the circuit board.

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