A sandwich structure power module

Abstract

The sandwich structure power module of the present invention comprises a stacked inductor group, a PCB board and a power device chip. The inductor group comprises a magnetic core and a winding. At the same time, the surface of the magnetic core is covered with metal sheets, and the metal sheets are combined in pairs for connecting to the high-power pins of the power device chip through the PCB board. Compared with the prior art, the power module of the present invention can reduce the area on the PCB board, thereby improving the load current / power density. In addition, the power module of the present invention transmits the output current through the pins (windings) of the inductor, which can reduce the routing of the output current loop on the PCB board, avoid the high impedance of the PCB board routing, and thus improve the circuit efficiency. In addition, the structure of the power device chip on the top and the inductor group on the bottom of the present invention can greatly benefit from the top cooling system commonly used in GPU, CPU and ASIC systems.

Description

Technical Field

[0001] The present invention relates to electronic components, and more particularly to a power module structure. Background Art

[0002] Typically, a power converter converts input power into output power of suitable voltage and current for the load. Multiphase power converters, which consist of multiple power stages connected in parallel and operating in staggered phases, offer advantages such as low output voltage ripple, fast transient response, and low input capacitor ripple current requirements. These advantages have led to their widespread use in high-current, low-voltage applications such as servers and microprocessors.

[0003] The rapid development of modern GPUs (graphics processing units) and CPUs (central processing units) has placed increasing demands on the current capabilities of multiphase power converters. At the same time, these processors are becoming increasingly smaller, which means that the size of multiphase power converters must also be reduced. The increasing current and decreasing size have made the heat dissipation of multiphase power converters more challenging. This requires a power converter with high current density, high efficiency, and excellent heat dissipation capabilities. Summary of the Invention

[0004] An object of the present invention is to provide a power module with a sandwich structure, wherein the power module integrates an inductor, a power switch and a driver thereof in a power circuit system in a stacked manner into a smaller module.

[0005] According to one embodiment of the present invention, an inductor group that can be used in a power module includes: a magnetic core having N channels extending from top to bottom through the magnetic core, where N is an integer greater than 1; N windings, each passing through the N channels of the magnetic core; and two groups of metal sheets, each group including two metal sheets bonded together after an isolation layer is added therebetween, the two groups of metal sheets respectively covering two opposing sides of the magnetic core, and the two metal sheets in each group of metal sheets being electrically connected to different potentials.

[0006] A power module according to one embodiment of the present invention includes the aforementioned inductor group, and also includes: a PCB (printed circuit board) top plate located above the inductor group; and N power device chips located above the PCB top plate, wherein each power device chip has at least one pin electrically connected to a corresponding winding through the PCB top plate.

[0007] In one embodiment, the power module further includes: a PCB bottom plate located below the inductor group; and a connector connecting the PCB top plate and the PCB bottom plate, wherein the connector has a plurality of metal columns, which are respectively soldered to corresponding pads on the PCB top plate and the PCB bottom plate.

[0008] According to one embodiment of the present invention, an inductor group that can be used in a power module includes: a magnetic core having N channels running through the magnetic core from top to bottom, where N is an integer greater than 1; N windings, each passing through the N channels of the magnetic core; and a first metal sheet, a second metal sheet, and a third metal sheet, wherein the first metal sheet and the second metal sheet respectively cover two opposite side surfaces of the magnetic core, and the third metal sheet covers one of the remaining side surfaces of the magnetic core.

[0009] The power module with a sandwich structure of the present invention has the following advantages: (1) compared with the power module with a flat structure in the prior art, it can reduce the area on the PCB board, thereby improving the load current / power density; (2) by transmitting the output current through the legs (windings) of the inductor, it can reduce the routing of the output current loop on the PCB board, avoid the high impedance of the PCB board routing, and thus improve the circuit efficiency; and (3) the structure of the power module of the present invention with the power device chip on the top and the inductor group on the bottom can greatly benefit from the top cooling system commonly used in GPU, CPU and ASIC systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to better understand the present invention, the present invention will be described in detail with reference to the following drawings:

[0011] Figure 1 shows a schematic diagram of the circuit structure of an existing multi-phase power converter 10;

[0012] Figure 2 1 shows a schematic diagram of a power module 20 with a sandwich structure and integrated dual-phase power converter according to an embodiment of the present invention;

[0013] Figure 3 shows a three-dimensional exploded view of an inductor group 30 according to an embodiment of the present invention;

[0014] Figure 4 shows a three-dimensional exploded view of an inductor group 40 according to an embodiment of the present invention;

[0015] Figure 5 shows a three-dimensional exploded view of an inductor group 50 according to an embodiment of the present invention;

[0016] Figure 6 shows a schematic structural diagram of a magnetic core 60 according to an embodiment of the present invention;

[0017] Figure 7 A schematic structural diagram of a magnetic core 70 according to an embodiment of the present invention is shown;

[0018] Figure 8 shows a three-dimensional exploded view of an inductor group 80 according to an embodiment of the present invention;

[0019] Figure 9 shows a three-dimensional exploded view of an inductor group 90 according to an embodiment of the present invention;

[0020] Figure 10 shows a three-dimensional exploded view of an inductor group 100 according to an embodiment of the present invention;

[0021] Figure 11 shows a three-dimensional exploded view of the inductor group 110 according to one embodiment of the present invention;

[0022] Figure 12 shows a three-dimensional exploded view of the inductor group 120 according to one embodiment of the present invention;

[0023] Figure 13 FIG. 1 shows a three-dimensional exploded view of the inductor group 130 according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In the following description, some specific details, such as the specific circuit structures and specific parameters of these circuit components in the embodiments, are used to provide a better understanding of the embodiments of the present invention. Those skilled in the art will understand that the embodiments of the present invention can be implemented even without some details or in the case of other methods, components, materials, etc. In addition, the term "coupled" as used herein means directly connected or indirectly connected through other circuit components.

[0025] The embodiments described below will use specific implementation devices and application backgrounds as examples to illustrate the devices and working methods of various embodiments of the present invention, so that those skilled in the art can better understand the present invention. However, those skilled in the art should understand that these descriptions are merely illustrative and are not intended to limit the scope of the present invention.

[0026] Figure 1 FIG. 1 shows a schematic diagram of the circuit structure of an existing multi-phase power converter 10. Figure 1 As shown, the multi-phase power converter 10 includes a controller 101, N power devices 103 and N inductors L1, where N is an integer and N>1. Figure 1 As shown, each power stage 102, also referred to as each phase 102, includes a power device 103 and an inductor L1. Each power device 103 includes a power switch M1, M2 and a driver DR1 for driving the power switches M1, M2. The controller 101 provides N-phase control signals 105-1 to 105-N to control the N power devices 103 respectively, so as to control the N phases 102 to work in staggered phases. That is, the N inductors L1 sequentially draw energy from the input terminal and sequentially provide energy to the load 104. It should be understood that in Figure 1In this application, connecting the outputs of each phase of the multi-phase power converter 10 together to provide energy to the load is only one example. In other applications, the multi-phase power converter 10 can also operate in the manner of multiple single-phase power converters, that is, each phase can be connected to an independent load and provide different output voltages to meet the needs of different loads.

[0027] Figure 1 The power stage 102 having the BUCK topology is shown for example only. It should be understood by those skilled in the art that power stages having other topologies are also applicable to the multi-phase power converter according to the embodiment of the present invention.

[0028] In the following embodiments of the present invention, the inductor L1 may be implemented by a coupled inductor or by N single inductors.

[0029] When N=2, the multiphase power converter 10 is used as a dual-phase power converter, or two independent power converters.

[0030] Figure 2 FIG. 2 shows a schematic structural diagram of a power supply module 20 with a sandwich structure and an integrated dual-phase power converter according to an embodiment of the present invention. Figure 1 In the example, when N=2, the power stage 102 can be implemented using the power module 20 . The sandwich-structured power module 20 includes: a PCB (Printed Circuit Board) bottom plate 201 located at the bottom of the power module 20; an inductor group 206 located on the PCB bottom plate 201 and including two inductors, each of which has a first end and a second end; a PCB top plate 202 located on the inductor group 206; a connector 204 having a plurality of metal pillars 205, each of which is soldered to a corresponding pad on the PCB top plate 202 and the PCB bottom plate 201; and two power device chips 203 located on top of the PCB top plate 202, each of which has one or more pins connected to the second end of the inductor in the inductor group 206 through the PCB top plate 202; and each inductor having a winding 207, with both ends of the winding 207 bent to a plane perpendicular to the length of the winding 207 and extending on the PCB top plate 202 and the PCB bottom plate 201.

[0031] exist Figure 2 In the embodiment, the power module 20 further includes discrete components 208 located on the PCB top plate 202. The discrete components 208 are a general term that includes discrete resistors, discrete capacitors, etc. involved in the power converter 10, such as input capacitors for providing pulse current at the input end of the power converter 10, and filter capacitors and resistors for powering the power switch driver and internal logic circuits.

[0032] In one embodiment, the metal pillars 205 include copper pillars, which are used to solder the PCB bottom plate 201 to the PCB top plate 202. It should be understood by those skilled in the art that any metal pillars that can be used to electrically connect two PCBs can be used in the present invention.

[0033] The power module 20 is typically placed on the processor's motherboard to provide power to the motherboard's components. A PCB baseplate 201 is soldered to the motherboard, and some of the pins of the power module 20 are soldered to the motherboard through the PCB baseplate 201. In some embodiments, the PCB baseplate 201 can be omitted. The power module 20 can be directly soldered to the motherboard via a connector 204 and an inductor assembly 206.

[0034] In the present invention, the power device chip is stacked on the inductor group, such as Figure 2 As shown, the area of ​​the power converter 10 on the PCB is saved. Each power device chip 203 integrates Figure 1 The power device 103 shown includes the following Figure 1 The power switches M1 and M2 and the driver DR1 for driving the power switches M1 and M2 are shown, and Figure 1 The circuit connected to the auxiliary winding, etc., which are not shown in the figure. The pins of the power device chip 203 are soldered to the pads of the PCB top plate 202, and then the pads of the PCB top plate 202 are electrically connected to the pads of the PCB bottom plate 201 through the inductor group 206 and the connector 204. In this way, the power device chip 203 can be electrically connected through the PCB bottom plate 201. The power module 20 also includes a metal sheet 209 for conducting large current signals such as reference ground. The metal sheet 209 wraps part of the area of ​​the magnetic core of the inductor group 206 and is soldered to the PCB top plate 202 and the PCB bottom plate 201 at the same time. The position of the metal sheet 209 depends on the position of the ground pin of the power device chip 203. Figure 2 In the embodiment, the metal sheet 209 is mainly wrapped around the side of the inductor group 206, and its two ends are bent to form welding areas on the upper and lower surfaces of the inductor group 206 close to the corresponding pads on the PCB board. Therefore, on the horizontal plane, that is, the plane of the PCB board, the large area of ​​the metal sheet 209 replaces the PCB traces to carry large currents, thereby reducing circuit losses and improving circuit efficiency.

[0035] Figure 3 FIG. 3 shows a three-dimensional exploded view of an inductor group 30 according to an embodiment of the present invention. The inductor group 30 can be used as Figure 2 The inductor group 206 in the power module. Figure 3As shown, the inductor group 30 includes: a magnetic core, including a first magnetic core part 301 and a second magnetic core part 302, wherein the first magnetic core part 301 and the second magnetic core part 302 are combined together to form two channels 303-1 and 303-2 at the joint surface thereof; and windings 304-1 and 304-2, passing through the channels 303-1 and 303-2 respectively.

[0036] exist Figure 3 In the embodiment, when the inductor group 30 is applied to Figure 2 In the power module 20 shown in FIG. 1 , the channels 303 - 1 and 303 - 2 are parallel to the PCB bottom plate 201 and the PCB top plate 202 , that is, the channels 303 - 1 and 303 - 2 have a direction along the direction as shown in FIG. Figure 2 Radial to the axis A shown.

[0037] exist Figure 3 In this embodiment, the winding 304-1 has a first end 304-3 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB top plate 202 and is soldered to the PCB top plate 202. The winding 304-1 has a second end 304-5 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB bottom plate 201 and is soldered to the PCB bottom plate 201. In other words, the first end 304-3 and the second end 304-5 of the winding 304-1 extend along a plane perpendicular to the magnetic core channels 303-1 and 303-2, and the sides of the extended surface also extend along the surfaces of the PCB top plate 202 and the PCB bottom plate 201. Similarly, the winding 304-2 has a first end 304-4 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB top plate 202 and is soldered to the PCB top plate 202. The winding 304-2 has a second end 304-6 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB bottom plate 201 and is soldered to the PCB bottom plate 201. In other words, the first end 304-4 and the second end 304-6 of the winding 304-2 extend along a plane perpendicular to the magnetic core channels 303-1 and 303-2, and the sides of the extended surface also extend along the surfaces of the PCB top plate 202 and the PCB bottom plate 201.

[0038] exist Figure 3 In the embodiment, the shapes of the first magnetic core part 301 and the second magnetic core part 302 of the magnetic core are not symmetrical. The first magnetic core part 301 has a planar shape, and the second magnetic core part 302 has two channels. The channels 303-1 and 303-2 are respectively formed by the two channels of the second magnetic core part 302 and a surface 301-1 of the first magnetic core part 301. Figure 3 shown.

[0039] exist Figure 3 In this embodiment, the metal sheets 305-1 and 305-2 are L-shaped. The two ends of the metal sheets 305-1 and 305-2 are soldered to the PCB top plate 202 and the PCB bottom plate 201, respectively. The ends of the metal sheets 305-1 and 305-2 soldered to the PCB top plate 202 are bent 90 degrees, extending over the surface of the magnetic core, which is equivalent to extending over the surface of the PCB top plate 202. These metal sheets are electrically connected to the ground pins of the power device chip 203 via solder pads on the PCB top plate 202, thereby reducing the routing of the PCB top plate 202 and its routing impedance.

[0040] Figure 4 FIG. 4 shows a three-dimensional exploded view of an inductor group 40 according to an embodiment of the present invention. The inductor group 40 can be used as Figure 2 The inductor group 206 in the power module. Figure 4 As shown, the inductor group 40 includes: a magnetic core, including a first magnetic core part 401 and a second magnetic core part 402, wherein the first magnetic core part 401 and the second magnetic core part 402 are combined together to form two channels 403-1 and 403-2 at the joint surface thereof; and windings 404-1 and 404-2, passing through the channels 403-1 and 403-2 respectively.

[0041] exist Figure 4 In the embodiment, when the inductor group 40 is applied to Figure 2 In the power module 20 shown in FIG. 1 , the channels 403 - 1 and 403 - 2 are perpendicular to the PCB bottom plate 201 and the PCB top plate 202 , that is, the channels 403 - 1 and 403 - 2 have a direction along the direction as shown in FIG. Figure 2 Radial to the axis B shown.

[0042] exist Figure 4In this embodiment, the winding 404-1 has a first end 404-3 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB top plate 202 and is soldered to the PCB top plate 202. The winding 404-1 has a second end 404-5 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB bottom plate 201 and is soldered to the PCB bottom plate 201. In other words, the first end 404-3 and the second end 404-5 of the winding 404-1 extend along a plane perpendicular to the magnetic core channels 403-1 and 403-2, and their extended surfaces also extend along the surfaces of the PCB top plate 202 and the PCB bottom plate 201. Similarly, the winding 404-2 has a first end 404-4 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB top plate 202 and is soldered to the PCB top plate 202. The winding 404-2 has a second end 404-6 that is bent 90 degrees and extends along the surface of the magnetic core, partially covering the surface. This extended portion also extends along the surface of the PCB bottom plate 201 and is soldered to the PCB bottom plate 201. In other words, the first end 404-4 and the second end 404-6 of the winding 404-2 extend along a plane perpendicular to the magnetic core channels 403-1 and 403-2, and their extended surfaces also extend along the surfaces of the PCB top plate 202 and the PCB bottom plate 201.

[0043] In some embodiments, the second end 404-5 of the winding 404-1 and the second end 404-6 of the winding 404-2 may not be bent. Whether the second end of the winding is bent, the direction of the bend, and the shape of the extended surface are determined by the location of the corresponding pads on the PCB base plate 201. If there is no PCB base plate 202, the location of the corresponding pads on the motherboard where the power module 20 is located is determined.

[0044] exist Figure 4 In the embodiment, the shapes of the first core part 401 and the second core part 402 of the magnetic core are not symmetrical, wherein the first core part 401 has a planar shape, the second core part 402 has two channels, and the channels 403-1 and 403-2 are respectively composed of the two channels of the second core part 402 and a surface 401-1 of the first core part 401.

[0045] exist Figure 4In the embodiment, the metal sheets 405-1 and 405-2 have a C-shape. The two ends of the metal sheets 405-1 and 405-2 are respectively soldered to the PCB top plate 202 and the PCB bottom plate 201. The ends of the metal sheets 405-1 and 405-2 soldered to the PCB bottom plate 201 are bent 90 degrees and extended on the surface of the magnetic core, which is equivalent to extending on the surface of the PCB bottom plate 201. The extended surface is soldered to the corresponding pads of the PCB bottom plate 201, thereby reducing the routing of the PCB bottom plate 201 and its routing impedance. Similarly, the ends of the metal sheets 405-1 and 405-2 soldered to the PCB top plate 202 are bent 90 degrees and extended on the surface of the magnetic core, which is equivalent to extending on the surface of the PCB top plate 202. They are electrically connected to the ground pins of the power device chip 203 through the solder pads of the PCB top plate 202, thereby reducing the routing of the PCB top plate 202 and its routing impedance.

[0046] Figure 5 FIG. 3 shows a three-dimensional exploded view of an inductor group 50 according to an embodiment of the present invention. The inductor group 50 can be used as Figure 2 The inductor group 206 in the power module. Figure 5 As shown, the inductor group 50 includes: a magnetic core, including a first magnetic core part 501 and a second magnetic core part 502, wherein the first magnetic core part 501 and the second magnetic core part 502 are combined together to form two channels 503-1 and 503-2 at the joint surface thereof; and windings 504-1 and 504-2, passing through the channels 503-1 and 503-2 respectively.

[0047] exist Figure 5 In the embodiment, when the inductor group 50 is applied to Figure 2 In the power module 20 shown in FIG. 1 , the channels 503 - 1 and 503 - 2 are perpendicular to the PCB bottom plate 201 and the PCB top plate 202 , that is, the channels 503 - 1 and 503 - 2 have a direction along the direction as shown in FIG. Figure 2 Radial to the axis B shown.

[0048] exist Figure 5 In the embodiment, the metal sheet 505 has a C-shape. The two ends of the metal sheet 505 are respectively welded to the PCB top plate 202 and the PCB bottom plate 201. The end of the metal sheet 505 welded to the PCB bottom plate 201 is bent 90 degrees and extended on the surface of the magnetic core, which is equivalent to extending on the surface of the PCB bottom plate 201. The extended surface is welded to the corresponding pad of the PCB bottom plate 201, so as to reduce the routing of the PCB bottom plate 201 and its routing impedance. Similarly, the end of the metal sheet 505 welded to the PCB top plate 202 is bent 90 degrees and extended on the surface of the magnetic core, which is equivalent to extending on the surface of the PCB top plate 202, and is electrically connected to the ground pin of the power device chip 203 through the pad of the PCB top plate 202, so as to reduce the routing of the PCB top plate 202 and its routing impedance. Figure 5 In the embodiment, the portion of the metal sheet 505 that wraps the side surface of the magnetic core is extended as much as possible to increase the area and reduce its own impedance.

[0049] and Figure 4 Compared to the inductor group 40 shown, Figure 5 The inductor group 50 has a single metal sheet 505 for electrically connecting the ground pin of the power device chip 203 to the PCB bottom plate 201. Figure 4 compared to, Figure 5 Since one metal sheet is missing, the metal sheet 505 and the windings 504 - 1 and 504 - 2 have a larger extensible area on the upper and lower surfaces of the magnetic core, thereby making the distribution of the ground pins of the power device chip 203 more flexible.

[0050] Figure 5 In the embodiment, the first core part 501 and the second core part 502 of the magnetic core are connected to Figure 4 The core structure is similar to that in FIG, and for the sake of simplicity, it will not be described here.

[0051] Figure 6 FIG. 1 shows a schematic structural diagram of a magnetic core 60 according to an embodiment of the present invention. Figure 6 In the embodiment, the magnetic core 60 comprises a first magnetic core portion 601 and a second magnetic core portion 602 of symmetrical shapes, wherein each magnetic core portion has two channels. Figure 3-Figure 5 In the inductor assembly of the embodiment, the channels of the two magnetic core parts overlap to form two channels for the winding to pass through.

[0052] Figure 7 FIG. 1 shows a schematic structural diagram of a magnetic core 70 according to an embodiment of the present invention. Figure 7 In the embodiment, the magnetic core 70 includes a first magnetic core portion 701, a second magnetic core portion 702, and third magnetic core portions 703-1 to 703-3. The first magnetic core portion 701, the second magnetic core portion 702, and the third magnetic core portions 703-1 and 703-2 form a first channel 704-1. The first magnetic core portion 701, the second magnetic core portion 702, and the third magnetic core portions 703-2 and 703-3 form a second channel 704-2. Figure 7 As can be seen in FIG, when there are more third core parts, more core channels can be constructed. The first core part 701, the second core part 702 and the third core parts 703-1 to 703-3 can be made of different materials, thereby providing a more flexible and adjustable inductance-current curve.

[0053] In some embodiments of the present invention, the various core portions of the magnetic core can be made of the same material but have different shapes. Alternatively, the core portions can be made of different materials, such as ferrite, iron powder, or other suitable materials, to achieve a desired inductance-current characteristic curve, for example, a high inductance at low currents and a low inductance at high currents. High inductance at low currents can improve system efficiency, while low inductance at high currents can improve system transient performance.

[0054] In order to briefly explain the principle of the present invention, Figure 3-Figure 5 The embodiment shown in FIG. 1 only shows a magnetic core having two channels through which two windings can pass. A person skilled in the art will appreciate that, depending on the application requirements, the magnetic core can have any number of channels through which any number of windings can pass, and single or multiple channels are both consistent with the spirit of the present invention.

[0055] In some embodiments, air gaps may exist between different core sections of the magnetic core to form coupled inductors. In some embodiments, there are no air gaps between the core sections, thereby forming multiple single inductors.

[0056] In the present invention, in order to make the surface of the inductor module flat, the windings and metal sheets covering the surface of the magnetic core are embedded in the surface of the magnetic core, such as Figure 3-5 shown.

[0057] Figure 8 FIG. 1 shows a three-dimensional exploded view of an inductor group 80 according to an embodiment of the present invention. The inductor group 80 can be used as Figure 2 Inductor 206 in the power module. Figure 8 As shown, the inductor group 80 includes: a magnetic core 801 having a symmetrical structure when viewed from the top, two channels 801-1 and 801-2 extending from the upper surface 801-3 of the magnetic core 801 to the lower surface 801-4, and symmetrically distributed on both sides of the central axis "D" of the top view; and coils 802-1 and 802-2 passing through the channels 801-1 and 801-2, respectively.

[0058] exist Figure 8 In this embodiment, when the inductor 80 is applied to Figure 2 In the power module 20 shown in FIG. 1 , the channels 801 - 1 and 801 - 2 are perpendicular to the PCB bottom plate 201 and the PCB top plate 202 , that is, the channels 801 - 1 and 801 - 2 have a direction along the direction as shown in FIG. Figure 2 Radial to the axis B shown.

[0059] of Figure 8 In an embodiment, the coils 802 - 1 and 802 - 2 are straight bar structures.

[0060] exist Figure 8In the embodiment, the metal sheets 803-1, 803-2, 805-1 and 805-2 are C-shaped when viewed from the side, closely attached to the magnetic core 801 and partially wrapping the magnetic core 801. The metal sheets 805-1, 805-2 and 806 are used to solder the PCB top plate 202 and the PCB bottom plate 201. Figure 8 As shown, both ends of the metal sheets 803-1, 803-2, 805-1 and 805-2 are bent 90 degrees and extended along the PCB top plate 202 and the PCB bottom plate 201. The extended surface is soldered to the corresponding pads of the PCB top plate 202 and the PCB bottom plate 201, thereby saving the internal wiring of the PCB board and minimizing the high impedance caused by the internal wiring of the PCB board. In one embodiment, the metal sheets 803-1 and 803-2 are used to connect the power pins ( Figure 1 The metal sheets 805-1 and 805-2 are used to electrically connect the ground pins of the power device chip 203 to the PCB bottom plate 201 or the main board through the PCB top plate 202. Figure 8 In this embodiment, the middle portions of the two ends of the metal sheets 803-1 and 803-2 are hollowed out, leaving portions on both sides for connection to the PCB board. Similarly, the two ends of the metal sheets 805-1 and 805-2 are hollowed out, leaving portions on both sides for connection to the PCB board. An isolation layer 804-1 is added between the metal sheets 803-1 and 805-1, and after being bonded together, it covers one side of the magnetic core 801. Similarly, an isolation layer 804-2 is added between the metal sheets 803-2 and 805-2, and after being bonded together, it covers the other, opposite side of the magnetic core 801. The isolation layer 804-1 is used to prevent the metal sheets 803-1 and 805-1 from shorting. The isolation layer 804-2 is used to prevent the metal sheets 803-2 and 805-2 from shorting. The metal sheets 803-1, 803-2, 805-1, and 805-2 are bent at their upper and lower ends to cover as much of the upper and lower surfaces of the magnetic core 801 as possible, thereby minimizing internal wiring on the PCB and reducing PCB wiring impedance. Furthermore, the metal sheets 803-1, 803-2, 805-1, and 805-2 are as wide as possible to reduce the resistance of the metal sheets themselves.

[0061] It should be understood that in some embodiments, the metal sheets 803-1 and 803-2 can be electrically connected to the ground pins of the power device chip 203 through the PCB top plate 202, and the metal sheets 805-1 and 805-2 can be electrically connected to the power pins of the power device chip 203 through the PCB top plate 202. That is, the potential connected to the metal sheets 803-1 and 803-2 and the potential connected to the metal sheets 805-1 and 805-2 can be interchangeable.

[0062] Figure 9 FIG. 1 shows a three-dimensional exploded view of an inductor group 90 according to an embodiment of the present invention. The inductor group 90 can be used as Figure 2 The inductor 206 in the power module. The inductor group 90 and Figure 8 The inductor group 80 is similar to that in Figure 9 In the embodiment, coils 902-1 and 902-2 are not as Figure 8 The coils 801-1 and 801-2 are both straight strip structures. Figure 9 In the embodiment, coils 902-1 and 902-2 each include three sections: a first section 902-A extending downward from and perpendicular to upper surface 901-3; a second section 902-B extending upward from and perpendicular to lower surface 901-4; and a third section 902-C connecting first sections 902-A and 902-B in the middle. In one embodiment, third section 902-C is radially parallel to upper surface 901-3 and lower surface 901-4 of the magnetic core.

[0063] Figure 10 FIG. 1 shows a three-dimensional exploded view of an inductor group 100 according to an embodiment of the present invention. The inductor group 100 can be used as Figure 2 The inductor 206 in the power module. The inductor group 100 and Figure 9 The inductor group 90 in is similar, the difference is that Figure 10 In the embodiment, the third portion 1002-C of each coil is long enough so that the first portion 1002-A and the second portion 1002-B of the coil are exposed on the surface of the magnetic core, wherein the exposed surfaces of the first portion 1002-A and the second portion 1002-B are flush with the surface of the magnetic core to make the surface of the magnetic core flat.

[0064] Figure 11 FIG. 1 shows a three-dimensional exploded view of an inductor group 110 according to an embodiment of the present invention. The inductor group 110 can be used as Figure 2 The inductor 206 in the power module. The inductor group 110 and Figure 10 The inductor group 100 is similar to that in Figure 11 In the embodiment, third portion 1102-C of each coil is long enough to expose first portion 1102-A and second portion 1102-B of the coil on the surface of the magnetic core. The exposed surfaces of first portion 1102-A and second portion 1102-B are flush with the surface of the magnetic core, thereby making the surface of the magnetic core smooth. In one embodiment, third portion 1102-C is radially parallel to upper surface 1101-3 and lower surface 1101-4 of the magnetic core.

[0065] Figure 12FIG. 1 shows a three-dimensional exploded view of an inductor group 120 according to an embodiment of the present invention. The inductor group 120 can be used as Figure 2 The inductor 206 in the power module. The inductor group 120 and Figure 10 The inductor group 100 is similar to that in Figure 12 In FIG, metal sheets 1203-1, 1203-2 and 1204 do not overlap each other. Figure 12 In the figure, metal sheets 1203-1 and 1203-2 cover two opposing sides of magnetic core 1001, while metal sheet 1204 covers any remaining side. From the side, metal sheets 1203-1, 1203-2, and 1204 all form a "C" shape. That is, each metal sheet is bent 90 degrees at both ends and wraps around portions of the upper surface 1001-3 and lower surface 1001-4 of magnetic core 1001.

[0066] exist Figure 12 In one embodiment, metal sheets 1203-1 and 1203-2 are connected to a first potential, while metal sheet 1204 is connected to a second potential. The first potential may be the potential of a ground pin of power device 203, and the second potential may be the potential of a power pin of power device 203, or vice versa.

[0067] Figure 13 FIG. 1 shows a three-dimensional exploded view of an inductor group 130 according to an embodiment of the present invention. The inductor group 130 can be used as Figure 2 The inductor 206 in the power module. The inductor group 130 and Figure 12 The inductor group 120 is similar to that in Figure 13 In FIG, the inductor group 130 includes more metal sheets, that is, the inductor group 130 includes metal sheets 1203-1, 1203-2, 1304-1 and 1304-2. Figure 13 In the embodiment, the metal sheets 1203-1 and 1203-2 cover two opposite sides of the magnetic core 1001 and are electrically connected to the first potential, while the metal sheets 1304-1 and 1304-2 cover the remaining two opposite sides and are electrically connected to the second potential. Figure 12 Similar to the metal sheets in FIG. 1 , metal sheets 1203-1, 1203-2, 1304-1, and 1304-2 are all C-shaped when viewed from the side. That is, each metal sheet is bent 90 degrees at both ends to wrap around portions of the upper surface 1001-3 and lower surface 1001-4 of the magnetic core 1001. The greater number of metal layers provides greater flexibility in the placement of solder pads on the top PCB 202 and bottom PCB 201 (or the motherboard where the power module resides).

[0068] In different embodiments of the present invention, the metal sheet can have different shapes to wrap the magnetic core. Furthermore, when the shape of the magnetic core changes, the shape of the metal sheet will also change accordingly. It should be understood that the metal sheet and the coil do not contact each other to prevent short circuits.

[0069] In some embodiments, Figure 8-13 The metal sheet in the embodiment can have different shapes, such as "L" shape, that is, one end of the metal sheet is bent and includes the upper surface or the lower surface of the magnetic core, such as Figure 3 As shown in the metal sheets 305-1 and 305-2 in FIG. Figure 8-13 Some of the metal sheets or metal sheets in the embodiment can be flat, i.e., no end is bent. Furthermore, in some embodiments, metal sheets of different shapes, such as "C"-shaped and flat, can be combined together as long as there is an isolation layer in between.

[0070] In the present invention, the coil passes through the channel inside the magnetic core, which means that the channel and the coil have a matching shape. In some embodiments, the coil is first shaped and then the magnetic core material is wrapped around the coil to manufacture the entire inductor.

[0071] In some embodiments of the present invention, the surface of the magnetic core is coated with epoxy resin to isolate the magnetic core from the metal layer covering the magnetic core.

[0072] In the present invention, in order to make the outer surface of the inductor flat, the portion of the coil exposed on the outer surface of the inductor and the metal layer covering the outer surface of the inductor are embedded into the outer surface of the inductor, such as Figure 3-5 As shown in 8-13.

[0073] In light of the above teachings, many modifications and variations of the present invention are readily apparent. Therefore, it should be understood that, within the scope of the claims, the present invention may be practiced without being specifically described above. It should also be understood that the above disclosure relates only to preferred embodiments of the present invention, and that modifications may be made to the present invention without departing from the spirit and scope of the claims. When only one preferred embodiment is disclosed, it will be readily apparent to those skilled in the art that modifications may be implemented without departing from the spirit and scope of the claims.

Claims

1. An inductor group that can be used in a power module, comprising: A magnetic core having N channels running through the core from top to bottom, where N is an integer greater than 1; N windings, each passing through N channels of the magnetic core; as well as Two groups of metal sheets, each group of metal sheets includes two metal sheets, which are bonded together after adding an isolation layer in the middle. The two groups of metal sheets respectively cover two opposite sides of the magnetic core, and the two metal sheets in each group of metal sheets are electrically connected to different potentials.

2. The inductor group according to claim 1, wherein: At least one of the metal sheets is in a "C" shape, with a first end bent and extending on the upper surface of the magnetic core, and a second end bent and extending on the lower surface of the magnetic core.

3. The inductor group according to claim 1, wherein: At least one of the metal sheets is in an inverted "L" shape, with one end bent and extending on the upper surface of the magnetic core.

4. The inductor group according to claim 1, wherein: At least one of the metal sheets is in an "L" shape, with one end bent and extending on the lower surface of the magnetic core. The inductor group as claimed in claim 1 , wherein the metal sheet has a planar shape.

6. The inductor group according to claim 1, wherein: The windings are straight.

7. The inductor group according to claim 1, wherein: Each winding includes a first part, a second part and a third part, wherein the first part extends downward from the upper surface of the magnetic core and is perpendicular to the upper surface of the magnetic core, the second part extends upward from the lower surface of the magnetic core and is perpendicular to the lower surface of the magnetic core, and the third part connects the first part and the second part inside the magnetic core. 8 . The inductor assembly of claim 7 , wherein the length of the third portion is parallel to the upper surface of the magnetic core and is long enough to allow the first portion and the second portion to be exposed at a side surface of the magnetic core.

9. The inductor group according to claim 1, wherein: Each winding includes a first part, a second part and a third part, wherein the first part extends from the side of the magnetic core to the inside of the magnetic core and is exposed on the upper surface of the magnetic core, the second part extends from the other opposite side of the magnetic core to the inside of the magnetic core and is exposed on the lower surface of the magnetic core, and the third part connects the first part and the second part inside the magnetic core.

10. A power module, comprising the inductor group according to any one of claims 1 to 9, further comprising: The top plate of the PCB (printed circuit board), located above the inductor group; as well as N power device chips are located on the top plate of the PCB, wherein each power device chip has at least one pin electrically connected to a corresponding winding through the top plate of the PCB.

11. The power module according to claim 10, further comprising: PCB bottom plate, located under the inductor group; as well as A connector connects a PCB top plate and a PCB bottom plate, wherein the connector has a plurality of metal columns, which are respectively welded to corresponding pads of the PCB top plate and the PCB bottom plate.

12. An inductor group that can be used in a power module, comprising: A magnetic core having N channels running through the core from top to bottom, where N is an integer greater than 1; N windings, each passing through N channels of the magnetic core; as well as A first metal sheet, a second metal sheet and a third metal sheet, wherein the first metal sheet and the second metal sheet respectively cover two opposite side surfaces of the magnetic core, and the third metal sheet covers one of the remaining side surfaces of the magnetic core.

13. The inductor group according to claim 12, wherein: The first metal sheet and the second metal sheet are electrically connected to a first potential, and the third metal sheet is electrically connected to a second potential. 14 . The inductor assembly as claimed in claim 12 , further comprising a fourth metal sheet covering a side surface of the magnetic core opposite to the side surface where the third metal sheet is located.

15. The inductor group according to claim 14, wherein: The first and second metal sheets are electrically connected to a first potential, and the third and fourth metal sheets are electrically connected to a second potential.

16. The inductor group according to claim 12, wherein: Each winding includes a first part, a second part and a third part, wherein the first part extends downward from the upper surface of the magnetic core and is perpendicular to the upper surface of the magnetic core, the second part extends upward from the lower surface of the magnetic core and is perpendicular to the lower surface of the magnetic core, and the third part connects the first part and the second part inside the magnetic core. 17 . The inductor assembly of claim 16 , wherein the length of the third portion is parallel to the upper surface of the magnetic core and is long enough to allow the first portion and the second portion to be exposed at a side surface of the magnetic core.

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