TWI897001B - Sandwich structure power supply module - Google Patents

Abstract

A power supply module having at least one inductor modules, a top PCB (Printed Circuit Board), and at least one pair of power device chips is provided in the present invention. The top PCB is mounted on top of the inductor modules, and the power device chips are mounted on top of the top PCB. Power pins and signal pins are implemented by metal layers wrapping the inductor modules, for connecting the top PCB and a board that the inductor modules are attached to. The power supply module in the present invention has simple structure, high integration, low module height, short current path, low power loss, and a processor system used with the power module has excellent heat dissipation.

Description

Power module with sandwich structure

The presently disclosed embodiments relate to electronic devices, and more particularly, to power modules.

Typically, a power converter converts input power into output power of appropriate voltage and current for the load. Multiphase power converters consist of multiple power stages connected in parallel and operating in staggered phases. They offer advantages such as low output voltage ripple, fast transient response, and low input capacitor rated ripple current requirements. Due to these advantages, multiphase power converters are widely used in applications requiring high output current and low voltage, such as servers and microprocessors.

The rapid development of modern graphics processing units (GPUs) and central processing units (CPUs) has placed increasing demands on the current capabilities of multiphase power converters. At the same time, these processors are becoming increasingly smaller, which in turn requires a corresponding reduction in the size of multiphase power converters. This increasing current coupled with shrinking size creates even greater challenges for heat dissipation within these converters. This requires a power converter with high current density, high efficiency, and excellent heat dissipation capabilities.

The present disclosure aims to provide a power module with a sandwich structure that integrates an inductor, a power switch, and a driver stack into a smaller power module.

According to an embodiment of the present disclosure, a power module is provided, comprising at least one inductor module, a printed circuit board (PCB) top plate, and at least one pair of power device chips. Each inductor module includes a magnetic core and two coils passing through the core. The PCB top plate is positioned above at least one inductor module. The power device chips are positioned above the PCB top plate, with each pair of power device chips positioned above the corresponding inductor module on the PCB top plate, and at least one pin of each power device chip connected to the corresponding coil of the corresponding inductor module through the PCB top plate. Each inductor module is encapsulated by multiple metal sheets, wherein the metal sheets are configured as power pins and signal pins for connecting the PCB top plate to the circuit board on which the inductor module is located.

According to embodiments of the present disclosure, a processor system is provided, comprising a power module, a motherboard, a load, and a top-side cooling system. The power module includes at least one inductor module, a PCB top plate, and at least one pair of power device chips. Each inductor module includes a magnetic core and two coils passing through the core. The PCB top plate is positioned above the at least one inductor module. The power device chips are positioned above the PCB top plate, with each pair of power device chips positioned above the corresponding inductor module on the PCB top plate. At least one pin of each power device chip is connected to the corresponding coil of the corresponding inductor module through the PCB top plate. Each inductor module is encapsulated by multiple metal sheets configured as power and signal pins, connecting the PCB top plate to the circuit board where the inductor module resides. The load is located above the motherboard. The top cooling system is located above the load and the power module. The power module is located above the motherboard near the load to supply power to the load.

According to embodiments of the present disclosure, an inductor module is also provided, comprising a magnetic core, at least one coil, and a plurality of metal sheets. The magnetic core includes at least one channel. The at least one coil passes through the at least one corresponding channel of the magnetic core. The metal sheets cover the magnetic core. Each metal sheet is C-shaped and wraps around a portion of the side surface of the magnetic core. It has a first end and a second end. The bent first end covers a portion of the top of the magnetic core, and the bent second end covers a portion of the bottom of the magnetic core. The metal sheets are configured as power pins and signal pins.

In the disclosed embodiments, the power module has the advantages of simple structure, high integration, low module height, short current path, and low power loss. Furthermore, the processor system equipped with the power module has better heat dissipation.

101: Controller

102: Power Level

103: Power Device

104: Load

140: Inductor module

170,180:Processor System

1701: Motherboard

1702: Power module

1703: Load

1704,1804: Top cooling system

1804-1: Container

1804-2: Pipeline

M1, M2: Power switches

DR1: Drive

L1, 80, 90, 100: Inductor

20,150,160: Power module

201, 1501, 1601: PCB base plate

202, 1502, 1602: PCB top plate

203: Power device chip

204: Connector

205:Metal Column

206: Inductor Set

207,304-1,304-2,404-1,404-2,504-1,504-2,802-1,802-2,902-1,902-2,1002-1,1002-2,1102-1,1102-2,1412,1413: Coil

208: Components

209,305-1,305-2,405-1,405-2,505,803-1,803-2,805-1,805-2,1203-1,1203-2,1204,1304-1,1304-2,1401~1408: Metal Sheet

30, 40, 50, 110: Inductor Set

301, 302, 401, 402, 501, 502, 601, 602, 701, 702, 703-1, 703-2, 703-3: Magnetic core

303-1, 303-2, 403-1, 403-2, 503-1, 503-2, 704-1, 704-2, 801-1, 801-2, 901-1, 901-2, 1001-1, 1001-2, 1101-1, 1101-2: Channel

304-3,304-4,304-5,304-6,404-3,404-4,404-5,404-6,504-3,504-4,504-5,504-6: Endpoints

301-1, 401-1, 501-1: Face

60, 70, 801, 901, 1001, 1101, 1415: Magnetic core

801-3,801-4,901-3,901-4,1001-3,1001-4,1101-3,1101-4,1415-1,1415-2,1415-3,1415-4: Surface

804-1, 804-2: Isolation Layer

902-A, 902-B, 902-C, 1102-A, 1102-B, 1102-C: Coil section

105-1~105-N: Control signal

To better understand the present invention, the present disclosure will be described in detail with reference to the following figures.

FIG1 shows a schematic diagram of the circuit structure of a conventional multi-phase power converter 10. FIG2 shows a schematic diagram of the structure of a power module 20 with a sandwich structure and integrated dual-phase power converter according to an embodiment of the present invention. FIG3 shows a three-dimensional exploded view of an inductor assembly 30 according to an embodiment of the present invention. FIG4 shows a three-dimensional exploded view of an inductor assembly 40 according to an embodiment of the present invention. FIG5 shows a schematic diagram of the structure of a power module 20 with a sandwich structure and integrated dual-phase power converter according to an embodiment of the present invention. FIG6 shows a schematic diagram of the structure of a magnetic core 60 according to an embodiment of the present invention; FIG7 shows a schematic diagram of the structure of a magnetic core 70 according to an embodiment of the present invention; FIG8 shows a schematic diagram of the structure of an inductor group 80 according to an embodiment of the present invention; FIG9 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG10 shows a schematic diagram of the structure of an inductor group 80 according to an embodiment of the present invention; FIG11 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG12 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG13 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG14 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG15 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG16 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG17 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG18 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG19 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG11 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG14 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG15 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG16 shows a schematic diagram of the structure of an inductor group 90 according to an embodiment of the present invention; FIG17 shows a schematic diagram of the structure of an inductor [Figure 11] shows a three-dimensional exploded view of an inductor assembly 110 according to an embodiment of the present invention; [Figure 12] shows a three-dimensional exploded view of an inductor assembly 120 according to an embodiment of the present invention; [Figure 13] shows a three-dimensional exploded view of an inductor assembly 130 according to an embodiment of the present invention; [Figure 14] shows a three-dimensional exploded view of an inductor assembly 130 according to an embodiment of the present invention. FIG15 shows a schematic structural diagram of a power module 150 according to an embodiment of the present invention; FIG16 shows a schematic structural diagram of a power module 160 according to an embodiment of the present invention; FIG17 shows a schematic structural diagram of a processor system 170 according to an embodiment of the present invention; and FIG18 shows a schematic structural diagram of a processor system 180 according to an embodiment of the present invention.

In the accompanying drawings, the same or corresponding reference numerals are used to represent the same or corresponding elements.

Specific embodiments of the present invention are described in detail below. It should be noted that the embodiments described herein are for illustrative purposes only and are not intended to limit the present invention. In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that these specific details are not required to practice the present invention. In other instances, well-known circuits, materials, or methods are not described in detail to avoid obscuring the present invention.

Throughout this specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment," "in an embodiment," "one example," or "an example" throughout this specification are not necessarily all referring to the same embodiment or example. It should be understood that when an element is referred to as being "coupled to" or "connected to" another element, it can be directly coupled or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly coupled to" or "directly connected to" another element, there are no intervening elements present. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combinations and/or subcombinations in one or more embodiments or examples. Furthermore, those skilled in the art will appreciate that the figures provided herein are for illustrative purposes only and are not necessarily drawn to scale. Like reference numerals denote like elements. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

FIG1 shows a schematic diagram of the circuit structure of a conventional multi-phase power converter 10. As shown in FIG1 , 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. As shown in FIG1 , 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 power switches M1 and M2 and a driver DR1 for driving the power switches M1 and M2. The controller 101 provides N-phase control signals 105-1 to 105-N to control the N power devices 103, respectively, to control the N phases 102 to operate out of phase. That is, the N inductors L1 sequentially draw energy from the input and sequentially provide energy to the load 104. It should be understood that in Figure 1, connecting the output phases of the multi-phase power converter 10 together to provide energy to a load is only one application. In other applications, the multi-phase power converter 10 can also operate as multiple single-phase power converters. That is, each phase can be connected to an independent load and provide different output voltages to meet the requirements of different loads.

The power stage 102 with a Buck topology shown in FIG1 is for example only. Those skilled in the art will appreciate that power stages with other topologies, such as Boost and Buck-Boost, are also applicable to the multi-phase power converters of the present invention.

In the following embodiments of the present invention, the inductor L1 can be implemented as a coupled inductor or as N single inductors.

When N=2, the multi-phase power converter 10 is used as a dual-phase power converter, or two independent single-phase power converters.

FIG2 shows a schematic structural diagram of a power module 20 with a sandwich structure integrated with a dual-phase power converter according to an embodiment of the present invention. In FIG1 , when N=2, the power stage 102 can be implemented using the power module 20. The sandwich power module 20 includes a printed circuit board (PCB) base plate 201, located at the bottom of the power module 20; an inductor group 206, located above the PCB base plate 201. The inductor group 206 includes two inductors, each with a first end and a second end; a PCB top plate 202, located above the inductor group 206; a connector 204 having multiple metal posts 205, each soldered to a corresponding pad on the PCB top plate 202 and the PCB base plate 201; and two power device chips 203, located on the PCB top plate 202. Each power device chip 203 has one or more pins connected to the second end of the inductor in the inductor group 206 through the PCB top plate 202. Each inductor has a coil 207, the two ends of which are bent onto a plane perpendicular to the length of the coil 207 and extend on the PCB top plate 202 and the PCB bottom plate 201.

In Figure 2, the power module 20 also includes other components 208 separately located on the PCB top board 202. Components 208 are a general term and include, for example, discrete resistors and capacitors within the power converter 10. For example, the input capacitor used to provide pulse current at the input of the power converter 10, the filter capacitors and resistors used to power the driver and internal logic circuits, and so on.

In one embodiment, the metal pillar 205 comprises a copper pillar, which is 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 pillar that can be used to connect two PCBs can be used in the present invention.

The power module 20 is typically mounted on the processor's motherboard to power the components on the motherboard. A PCB baseplate 201 is soldered to the motherboard to connect some pins of the power module 20 to the motherboard. 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.

In the present invention, the power device chip is stacked above the inductor assembly, as shown in Figure 2 , thereby saving PCB area for the power converter 10. Each power device chip 203 integrates the power device 103 shown in Figure 1 , including the power switches M1 and M2 and driver DR1, as well as auxiliary circuitry not shown in Figure 1 . The pins of the power device chip 203 are soldered to pads on the PCB top board 202. These pads are then electrically connected to pads on the PCB bottom board 201 via the inductor assembly 206 and connector 204. This ensures that the power device chip 203 receives information from the PCB bottom board 201. The power module 20 also includes a metal sheet 209 for conducting high-current signals, such as the reference ground. The metal sheet 209 partially wraps around the magnetic core of the inductor assembly 206 and is soldered to both the PCB top plate 202 and the PCB bottom plate 201. The position of the metal sheet 209 is determined by the location of the ground pins of the power device chip 203. In the embodiment shown in Figure 2, because the metal sheet primarily wraps around the sides of the inductor assembly 206, its ends are bent to form solder pads on the top and bottom surfaces of the inductor assembly 206, close to the ground pins of the power device chip 203. This allows the large metal sheet 209 to replace PCB traces to carry high current on the horizontal plane (i.e., the plane of the PCB), reducing circuit losses and improving circuit efficiency.

Figure 3 shows a three-dimensional exploded view of an inductor assembly 30 according to an embodiment of the present invention. Inductor assembly 30 can be used as inductor assembly 206 in Figure 2 . As shown in Figure 3 , inductor assembly 30 includes: a magnetic core comprising a first core portion 301 and a second core portion 302 , wherein the first core portion 301 and the second core portion 302 are combined to form two channels 303-1 and 303-2 at their joint surfaces; and coils 304-1 and 304-2 passing through channels 303-1 and 303-2, respectively, between the first core portion 301 and the second core portion 302 .

In the embodiment of FIG. 3 , when the inductor assembly 30 is applied to the power module 20 shown in FIG. 2 , 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 radial direction along the axis "A" shown in FIG. 2 .

In the embodiment shown in Figure 3, the coil 304-1 has a first end 304-3 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB top board 202 and is soldered to the PCB top board 202. The coil also has a second end 304-5 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB bottom board 201 and is soldered to the PCB bottom board 201. In other words, the first end 304-3 and second end 304-5 of the coil 304-1 extend along a plane perpendicular to the magnetic core channels 303-1 and 303-2, with the sides of the extended surface extending over the surfaces of both the PCB top board 202 and the PCB bottom board 201. Similarly, coil 304-2 has a first end 304-4 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB top board 202 and is soldered to it. It also has a second end 304-6 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB bottom board 201 and is soldered to it. In other words, the first end 304-4 and second end 304-6 of coil 304-2 extend along a plane perpendicular to the magnetic core channels 303-1 and 303-2, with the sides of their extended surfaces also extending over the surfaces of both the PCB top board 202 and the PCB bottom board 201.

In the embodiment shown in FIG3 , the shapes of the first core portion 301 and the second core portion 302 of the magnetic core are not symmetrical. The first core portion 301 is planar, while the second core portion 302 has two trenches. Channels 303-1 and 303-2 are formed by the two trenches of the second core portion 302 and a surface 301-1 of the first core portion 301, respectively, as shown in FIG3 .

In the embodiment shown in Figure 3, metal sheets 305-1 and 305-2 are L-shaped. The ends of metal sheets 305-1 and 305-2 are soldered to the PCB top plate 202 and PCB bottom plate 201, respectively. The ends of metal sheets 305-1 and 305-2 soldered to the PCB top plate 202 are bent 90 degrees and extended onto the surface of the magnetic core, effectively extending onto the surface of the PCB top plate 202. This extended surface is electrically connected to the ground pin of the power device chip 203 via a solder pad on the PCB top plate 202, thereby reducing the traces on the PCB top plate 202 and their impedance.

Figure 4 shows a three-dimensional exploded view of an inductor assembly 40 according to an embodiment of the present invention. Inductor assembly 40 can be used as inductor assembly 206 in Figure 2 . As shown in Figure 4 , inductor assembly 40 includes: a magnetic core comprising a first core portion 401 and a second core portion 402 , wherein the first core portion 401 and the second core portion 402 are combined to form two channels 403-1 and 403-2 at their joints; and two coils 404-1 and 404-2 , respectively passing through channels 403-1 and 403-2 between the first core portion 401 and the second core portion 402 .

In the embodiment of FIG. 4 , when the inductor assembly 40 is applied to the power module 20 shown in FIG. 2 , 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 radial direction along the axis "B" shown in FIG. 2 .

In the embodiment shown in FIG. 4 , coil 404-1 has a first end 404-3 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB top board 202 and is soldered to the PCB top board 202. Coil 404-1 has a second end 404-5 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB bottom board 201 and is soldered to the PCB bottom board 201. In other words, the first end 404-3 and the second end 404-5 of coil 404-1 extend along a plane perpendicular to the magnetic core channels 403-1 and 403-2, and their extended surfaces also extend over the surfaces of both the PCB top board 202 and the PCB bottom board 201. Similarly, coil 404-2 has a first end 404-4 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB top board 202 and is soldered to the PCB top board 202. It also has a second end 404-6 that bends 90 degrees and extends over the surface of the magnetic core, partially covering the surface. This extended portion also extends over the surface of the PCB bottom board 201 and is soldered to the PCB bottom board 201. In other words, the first end 404-4 and second end 404-6 of coil 404-2 extend along a plane perpendicular to the magnetic core channels 403-1 and 403-2, and their extended surfaces also extend over the surfaces of both the PCB top board 202 and the PCB bottom board 201.

In some embodiments, the second end 404-5 of coil 404-1 and the second end 404-6 of coil 404-2 may not be bent. Whether the second ends of the coils are 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 201 of the power module. If no PCB is present, the location of the corresponding pads on the motherboard where the power module 20 is located is determined.

In the embodiment shown in FIG4 , the shapes of the first core portion 401 and the second core portion 402 of the magnetic core are not symmetrical. The first core portion 401 is planar, while the second core portion 402 has two trenches. The channels 403-1 and 403-2 are respectively formed by the two trenches of the second core portion 402 and a surface 401-1 of the first core portion 401.

In the embodiment shown in Figure 4 , metal sheets 405-1 and 405-2 are C-shaped. Their ends are soldered to the PCB top plate 202 and PCB bottom plate 201, respectively. One end of each metal sheet 405-1 or 405-2, soldered to the PCB bottom plate 201, is bent 90 degrees and extended onto the surface of the magnetic core, effectively extending onto the surface of the PCB bottom plate 201. This extended surface is soldered to corresponding pads on the PCB bottom plate 201, thereby reducing traces on the PCB bottom plate 201 and reducing trace impedance. Similarly, metal sheets 405-1 and 405-2 are soldered to one end of the PCB top plate 202 and bent 90 degrees to extend on the surface of the magnetic core, effectively extending on the surface of the PCB top plate 202. This extended surface is electrically connected to the ground pin of the power device chip 203 via the solder pad on the PCB top plate 202, thereby reducing the traces on the PCB top plate 202 and their trace impedance.

Figure 5 shows a three-dimensional exploded view of an inductor assembly 50 according to an embodiment of the present invention. Inductor assembly 50 can be used as inductor assembly 206 in Figure 2 . As shown in Figure 5 , inductor assembly 50 includes: a magnetic core comprising a first core portion 501 and a second core portion 502 , wherein the first and second core portions 501 and 502 are combined to form two channels 503-1 and 503-2 at their joints; and coils 504-1 and 504-2 , respectively, passing through channels 503-1 and 503-2 between the first and second core portions 501 and 502 .

In the embodiment of FIG. 5 , when the inductor assembly 50 is applied to the power module 20 shown in FIG. 2 , 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 radial direction along the axis "B" shown in FIG. 2 .

In the embodiment shown in Figure 5 , the metal sheet 505 is C-shaped. Its two ends are soldered to the PCB top plate 202 and the PCB bottom plate 201, respectively. The end of the metal sheet 505 soldered to the PCB bottom plate 201 is bent 90 degrees, extending over the surface of the magnetic core, effectively extending over the surface of the PCB bottom plate 201. This extended surface is soldered to corresponding pads on the PCB bottom plate 201, thereby reducing the traces on the PCB bottom plate 201 and their impedance. Similarly, one end of the metal sheet 505 soldered to the PCB top plate 202 is bent 90 degrees, extending over the surface of the magnetic core. This effectively extends over the surface of the PCB top plate 202. This extended surface is electrically connected to the ground pin of the power device chip 203 via the solder pad on the PCB top plate 202, thereby reducing the traces on the PCB top plate 202 and their impedance. In the example shown in Figure 5, the center portion of the metal sheet 505 extends outwards to increase its area and reduce its own impedance.

Compared to the inductor assembly 40 in Figure 4 , the inductor assembly 50 in Figure 5 uses a single metal plate 505 to solder the ground pin of the PCB top plate 202 to the PCB bottom plate 201. Compared to Figure 4 , Figure 5 lacks a metal plate. As a result, the metal plate 505 and coils 504-1 and 504-2 have a larger area available on the upper and lower surfaces of the magnetic core, allowing greater flexibility in the layout of the ground pins of the power device chip 203.

In the embodiment of FIG5 , the first core portion 501 and the second core portion 502 of the magnetic core have similar structures to those of the magnetic core in FIG4 . For the sake of brevity, they will not be further described here.

Figure 6 shows a schematic diagram of the structure of a magnetic core 60 according to an embodiment of the present invention. In Figure 6, magnetic core 60 comprises a symmetrical first core portion 601 and a second core portion 602, each of which has two trenches. When magnetic core 60 is used in the inductor assembly of the embodiments of Figures 3 to 5, the trenches of the first core portion and the trenches of the second core portion overlap, forming two channels through which the coil passes.

Figure 7 shows a schematic diagram of the structure of a magnetic core 70 according to an embodiment of the present invention. In Figure 7 , magnetic core 70 includes a first core portion 701, a second core portion 702, and third core portions 703-1 through 703-3. The first core portion 701, the second core portion 702, and the third core portions 703-1 and 703-2 form a channel 704-1. The first core portion 701, the second core portion 702, and the third core portions 703-2 and 703-3 form a channel 704-2. As shown in Figure 7 , more core channels can be formed if more third core portions are included. The first core portion 701, the second core portion 702, and the third core portions 703-1 through 703-3 can be made of different materials to provide a more flexible and adjustable inductance-current curve.

In some embodiments of the present invention, the various core sections of a magnetic core may be made of the same material but have different geometries and/or component percentages to achieve a desired inductance-current characteristic curve, for example, high inductance at low currents and low inductance at high currents. High inductance at low currents can improve system efficiency, while low inductance at high currents can improve system transient response. In some embodiments, the various core sections of a magnetic core may also be made of different materials, such as ferrite, iron powder, or other suitable magnetic materials, to achieve the desired inductance curve.

To simplify the principles of the present invention, the embodiments shown in Figures 3-5 illustrate a magnetic core with two channels, capable of passing through two coils. Those skilled in the art will appreciate that, depending on the application, the magnetic core can have any number of channels, capable of passing through any number of coils. Single-channel or multi-channel configurations are all consistent with the present invention.

In some embodiments, air gaps may exist between the 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.

In the present invention, in order to make the inductor group have a flat surface, the coil and metal sheet covering the surface of the magnetic core are embedded in the surface of the magnetic core, as shown in Figures 3 and 4.

Figure 8 shows a three-dimensional exploded view of an inductor assembly 80 according to an embodiment of the present invention. Inductor assembly 80 can be used as inductor assembly 206 in Figure 2 . As shown in Figure 8 , inductor assembly 80 includes: a magnetic core 801 having a symmetrical structure when viewed from above. Magnetic core 801 has two channels 801-1 and 801-2 extending from an upper surface 801-3 of magnetic core 801 to a lower surface 801-4. A top view of magnetic core 801 reveals that the two channels are symmetrically located on either side of the central axis "D"; and coils 802-1 and 802-2, which pass through channels 801-1 and 801-2, respectively.

In the embodiment of FIG. 8 , when the inductor assembly 80 is applied to the power module 20 shown in FIG. 2 , 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 radial direction along the axis "B" shown in FIG. 2 .

In the embodiment of FIG8 , the coils 802-1 and 802-2 are straight strip-shaped structures.

In the embodiment shown in FIG8 , metal sheets 803-1, 803-2, 805-1, and 805-2 are C-shaped when viewed from the side, closely attached to and partially encasing magnetic core 801. The ends of metal sheets 803-1, 803-2, 805-1, and 805-2 are bent 90 degrees and extended. These extended surfaces are soldered to corresponding pads on the PCB bottom plate 201 and the PCB top plate 202, thereby reducing the internal trace impedance of the PCB bottom plate 201 and the PCB top plate 202. In one embodiment, metal sheets 803-1 and 803-2 solder the power pins of the power device chip 203 (the pins for receiving the input voltage Vin in FIG. 1 ) to the PCB bottom plate 201 or directly to the motherboard via the PCB top plate 202 to reduce PCB trace impedance. In the embodiment of FIG. 8 , the middle portions of the two extended surfaces of metal sheets 803-1 and 803-2 are removed, leaving two soldering areas. Based on the positions of the soldering areas left by metal sheets 803-1 and 803-2, the side portions of the two extended surfaces of metal sheets 805-1 and 805-2 are removed so that they can be placed between the two soldering areas of metal sheets 803-1 and 803-2. As shown in Figure 8, metal sheets 803-1 and 805-1 are bonded together and placed on one side of magnetic core 801, with an isolation layer 804-1 between them to prevent electrical contact between the two metal sheets. Simultaneously, metal sheets 803-2 and 805-2 are bonded together and placed on the other side of magnetic core 801, with an isolation layer 804-2 between them to prevent electrical contact between the two metal sheets. The ends of metal sheets 803-1, 803-2, 805-1, and 805-2 are bent 90 degrees and extended to create a sufficient surface area to minimize PCB trace impedance. Metal sheets 803-1, 803-2, 805-1, and 805-2 are also sufficiently wide to minimize their own impedance.

It should be understood that in some embodiments, 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 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. In other words, the connection potentials of metal sheets 803-1 and 803-2 and metal sheets 805-1 and 805-2 can be interchanged without departing from the spirit and scope of the present invention.

FIG9 illustrates a three-dimensional exploded view of an inductor assembly 90 according to an embodiment of the present invention. Inductor assembly 90 can be used as inductor assembly 206 in FIG2 . Inductor assembly 90 is similar to inductor assembly 80 in FIG8 . However, the shapes of coils 902-1 and 902-2 in FIG9 differ from the straight coils 802-1 and 802-2 in FIG8 . In FIG9 , coils 902-1 and 902-2 consist of three sections: 902-A, 902-B, and 902-C. The first portion 902-A extends from the upper surface 901-3 of the magnetic core 901 in a direction perpendicular to the upper surface 901-3; the second portion 902-B extends from the lower surface 901-4 of the magnetic core 901 in a direction perpendicular to the lower surface 901-4; and the third portion 902-C connects the first portion 902-A and the second portion 902-B. In one embodiment, the radius of the third portion 902-C is parallel to the upper surface 901-3 and the lower surface 901-4.

Figure 10 shows a three-dimensional exploded view of an inductor assembly 100 according to an embodiment of the present invention. Inductor assembly 100 can be used as inductor assembly 206 in Figure 2 . Inductor assembly 100 is similar to inductor assembly 90 in Figure 9 . However, in Figure 10 , the third portion 1002-C of the coil is long enough to expose the first portions 1002-A and 1002-B on the corresponding side surface 1001-5 of the magnetic core 1001. The exposed surfaces of coils 1002-1 and 1002-2 are flush with the corresponding side surface of the magnetic core 1001, giving the inductor assembly 100 a flat surface.

Figure 11 shows a three-dimensional exploded view of an inductor assembly 110 according to one embodiment of the present invention. Inductor assembly 110 can be used as inductor assembly 206 in Figure 2 . Inductor assembly 110 is similar to inductor assembly 100 in Figure 10 . However, in Figure 11 , the third portion 1102-C of each coil is sufficiently long to expose the first portion 1102-A and second portion 1102-B of the coil on the surface of the magnetic core. The exposed surfaces of the first portion 1102-A and second portion 1102-B are flush with the surface of the magnetic core, resulting in a flat surface. In one embodiment, third portion 1102-C is radially perpendicular to the upper surface 1101-3 and lower surface 1101-4 of the magnetic core.

FIG12 shows a three-dimensional exploded view of an inductor assembly 120 according to an embodiment of the present invention. Inductor assembly 120 can be used as inductor assembly 206 in FIG2 . Inductor assembly 120 is similar to inductor assembly 100 in FIG10 . However, in FIG12 , metal sheets 1203-1, 1203-2, and 1204 do not overlap one another. In FIG12 , metal sheets 1203-1 and 1203-2 overlap two opposing sides of magnetic core 1001, while metal sheet 1024 overlaps the remaining side. Viewed from the side, metal sheets 1203-1, 1203-2, and 1204 are all C-shaped, with their ends bent 90 degrees to cover portions of the upper surface 1001-3 and lower surface 1001-4 of magnetic core 1001.

In the embodiment of FIG12 , metal plates 1203-1 and 1203-2 are connected to a first potential, while metal plate 1204 is connected to a second potential. The first potential can be the potential of a ground pin of power device 203, and the second potential can be the potential of a power pin of power device 203, or vice versa.

FIG13 shows a three-dimensional exploded view of an inductor assembly 130 according to an embodiment of the present invention. Inductor assembly 130 can be used as inductor assembly 206 in FIG2 . Inductor assembly 130 is similar to inductor assembly 120 in FIG12 , except that inductor assembly 130 includes a greater number of metal sheets, namely, inductor assembly 130 includes metal sheets 1203-1, 1203-2, 1304-1, and 1304-2. In FIG13 , metal sheets 1203-1 and 1203-2 respectively cover two opposing sides of magnetic core 1001 and are electrically connected to a first potential, while metal sheets 1304-1 and 1304-2 respectively cover the remaining two opposing sides and are electrically connected to a second potential. Similar to Figure 12 , metal sheets 1203-1, 1203-2, 1304-1, and 1304-2 are all C-shaped, meaning each sheet is bent 90 degrees at both ends to cover portions of the upper surface 1001-3 and lower surface 1001-4 of the magnetic core 1001. Increasing the number of metal sheets allows for greater flexibility in the layout of solder pads on the top and bottom PCB boards 202 and 201 (or the motherboard where the power module resides).

In different embodiments of the present invention, the metal sheets can be reshaped to wrap around the magnetic core. Furthermore, as the shape of the magnetic core changes, the shape of the metal sheets also changes accordingly. It should be understood that all metal sheets and coils are isolated from each other to prevent electrical contact, i.e., short circuits.

In some embodiments, some or all of the metal sheets in Figures 8-13 may have other shapes, such as an L-shape, where one end of the metal sheet is bent to wrap around the upper or lower surface of the magnetic core, such as metal sheets 305-1 and 305-2 shown in Figure 3. In some embodiments, some or all of the metal sheets in Figures 8-13 may be planar, with no ends bent. Furthermore, in some embodiments, metal sheets of different shapes may overlap and be combined, requiring isolation layers between the metal sheets.

In this invention, the coil passes through a channel inside the core, meaning the channel's shape matches the coil. In some embodiments, the coil is shaped first and then wrapped with the core material to create the entire inductor.

In some embodiments of the present invention, the surface of the magnetic core is covered with an epoxy resin coating to isolate the magnetic core from the metal sheet that wraps the magnetic core.

In the present invention, to make the outer surface of the inductor smooth, the exposed portion of the coil and the metal layer covering the outer surface of the inductor are embedded into the outer surface of the inductor, as shown in Figures 3-5 and 8-13.

As shown in Figure 2, the sandwich power module 20 includes an inductor assembly 206 and a connector 204 with multiple metal posts 205. The metal posts are soldered to corresponding pads on the top and bottom PCB boards. In other words, the inductor assembly 206 and connector 204 are two independent components packaged between the top and bottom PCB boards. During the manufacturing process, the height tolerance of the inductor assembly 206 and connector 204 is limited, so it is necessary to maintain the same height as much as possible.

Figure 14 illustrates an inductor module 140 according to one embodiment of the present invention. Inductor module 140 integrates an inductor assembly and a connector into a single module. Pins 1401-1408, the metal sheet covering the surface of inductor module 140, function as the connector. In one embodiment, inductor module 140 replaces inductor assembly 206 and connector 204 in Figure 2. It is located between the top and bottom PCB boards and integrated into the power module.

Compared to the inductor assembly 206 in the previous embodiment, the size of the inductor module 140 increases horizontally and decreases vertically. The increased horizontal size is covered by signal pins 1401-1408. Furthermore, compared to the previous inductor assembly, the increased horizontal size of the inductor module 140 extends the length of the channel and coil. Therefore, when the inductor module 140 has the same height as the inductor assembly in the previous embodiment, the inductor module 140 has a higher inductance. Even if the inductor module 140 is shorter than the inductor assembly 206, the inductor module 140 can still maintain sufficient inductance and low resistance.

In the embodiment of Figure 14 , inductor module 140 includes two inductors, each consisting of a magnetic core 1415 and one of two coils 1412 and 1413 passing through a channel in magnetic core 1415. In some embodiments, the two inductors can be a coupled inductor. The structure of coils 1412 and 1413 is the same as that of the coils in Figures 9 , 10 , 12 , and 13 : the first ends of coils 1412 and 1413 extend to the top 1415-1 of inductor module 140, and the second ends extend to the bottom 1415-2 of inductor module 140. The first ends of coils 1412 and 1413 are respectively connected to power device chip 203 via the PCB top plate. The second ends of coils 1412 and 1413 are connected to the PCB bottom plate, or to the motherboard if a PCB bottom plate is not available.

In Figure 14 , coils 1412 and 1413 have rectangular cross-sections. Given the same area, a rectangular cross-section increases the effective length of the coils compared to a square cross-section. Furthermore, coils with rectangular cross-sections can reduce copper losses caused by the skinning effect of ripple currents and minimize the length difference between the coil's magnetic path and the magnetic core surrounding it. Coils 1412 and 1413 are exposed on the upper surface 1415-1 of the power module 140 through a rectangular cross-section. The long side of the rectangular cross-section is oriented along the "Y" direction, which is perpendicular to the length of coils 1412 and 1413. The short side of the rectangular cross-section of the upper surface 1415-1 of the power module 140 is oriented along the "X" direction, which is parallel to the length of coils 1412 and 1413. In other embodiments, the structures of coils 1412 and 1413 can be the same as those shown in Figures 3-5 and 11, and the structures of the inductor module's channel and the metal sheet located on the module's surface can be adjusted accordingly.

In the embodiment of FIG. 14 , inductor module 140 extends along the length of the channel through which coils 1412 and 1413 pass. Signal pins are arranged on sides 1415-3 and 1415-4 of inductor module 140 that are parallel to the length of the channel. Sides 1415-3 and 1415-4 are opposite and parallel to the lengthwise direction "X" of coils 1412 and 1413. In one embodiment, the signal pins on side 1415-3 connect to a power device located near side 1415-3 at the top of the power module, while the signal pins on side 1415-4 connect to other power devices located near side 1415-4 at the top of the power module.

In the embodiment shown in Figure 14 , signal pins 1401-1408 are C-shaped metal sheets wrapped around a magnetic core 1415. Their ends are located on the top and bottom surfaces of the magnetic core 1415, connecting to the top and bottom PCBs, respectively. If a bottom PCB is not present, the inductor module 140 is soldered to the motherboard where the load powered by the power module resides.

In the example of Figure 14 , signal pins 1401 and 1405 receive pulse width modulation (PWM) signals via the PCB top board shown in Figure 2 and provide them to power device chip 203. Signal pins 1402 and 1406 provide current sensing signals to power device chip 203 via the PCB top board. Signal pins 1403 and 1407 receive temperature sensing signals from power device chip 203 via the PCB top board. Signal pins 1404 and 1408 receive enable signals and provide them to power device chip 203 via the PCB top board. Metal pins 1409, 1410, 1411, and 1414, or power pins, can be connected to different potentials within the power module. For example, metal sheet 1409 can be connected to the input voltage Vin of power device chip 203, metal sheets 1410 and 1411 can be grounded, and metal sheet 1414 can be connected to the VCC power supply to power device chip 203.

It should be understood that the pins of the inductor module 140 are for illustrative purposes only. The number and arrangement of the pins can be adjusted based on the application to achieve the optimal current path between the inductor module 140 and the load powered by the power module.

Compared to the inductor assembly of the previous embodiment, the inductor module 140 in Figure 14 significantly reduces its height while maintaining a roughly equivalent inductance value. In the embodiments of Figures 3-5 and 8-13, the inductor assembly height ranges from 5mm to 8mm. The height H1 of the inductor module 140 ranges from 1mm to 3mm, typically 2mm. The reduced height of the inductor module 140 also reduces the height of the power module, allowing it to be placed behind the motherboard/PCB where the load resides. In other words, the power module is placed below the load, with the motherboard/PCB positioned between them. This significantly shortens the current path and reduces power loss.

Figure 15 illustrates a power module 150 according to an embodiment of the present invention. As shown in Figure 15 , power module 150 includes a PCB base plate 1501, a PCB top plate 1502, an inductor module 140, a power device chip 203, and multiple discrete components 208. Components 208 are distributed on the PCB top plate 1502 and adjacent to the power device module 203. As described in the previous embodiment, PCB base plate 1501 can be omitted. As shown in Figure 15 , the removal of the connector simplifies the power module structure, increases integration, and thus improves the manufacturing process.

FIG16 illustrates a power module 160 according to an embodiment of the present invention. Compared to the power module 150 in FIG15 , the power module 160 in FIG16 is further expanded to include four inductor modules 140 located between a PCB top plate 1602 and a bottom plate 1601. It should be understood that in other embodiments, the power module can be expanded as needed to include inductor modules with similar structures as shown in FIG16 .

FIG17 illustrates a processor system 170 according to an embodiment of the present invention. As shown in FIG17 , processor system 170 includes a motherboard 1701, a power module 1702, a load 1703, and a top cooling system 1704. In FIG17 , power module 1702 can be power module 150 of FIG15 , power module 160 of FIG16 , or a power module with more inductor modules. The bottom of power module 1702, or the bottom of inductor module 140, is directly soldered to the motherboard where the load is located. Load 1703 includes a GPU, a CPU, etc. Top cooling system 1704 includes a heat sink placed above power module 1702 and load 1703. Ideally, top cooling system 1704 should be in contact with both load 1703 and power module 1702 to achieve effective heat dissipation. However, in practical applications, power module 1702 is often taller than load 1703, as shown in Figure 17. In this case, there is a gap between top cooling system 1704 and load 1703. The larger the gap, the poorer the heat dissipation. Therefore, the height of power module 1702 needs to be reduced to shorten the distance between top cooling system 1704 and load 1703. Power module 1702 in Figure 17 includes inductor module 140, which is much shorter than traditional power modules. As previously mentioned, the height H1 of inductor module 140 is 1 mm to 3 mm. Therefore, compared to power modules using traditional inductor groups, the height of power module 1702 is reduced by 2mm to 7mm, which effectively improves heat dissipation capabilities.

FIG18 illustrates a processor system 180 according to an embodiment of the present invention. Compared to the processor system 170 of FIG17 , the processor system 180 employs a top cooling system 1804. Top cooling system 1804 includes a heat pipe heat sink. The heat pipe heat sink, i.e., top cooling system 1804, includes a container 1804-1 and a pipe 1804-2. As shown in FIG18 , both ends of pipe 1804-2 are bent. The power module 1702 is placed below the top cooling system 1804. When the distance between the top cooling system 1804 and the load 1703 is fixed, the lower the power module 1702 is, the closer it can be to the load 1703. It should be understood that the distance between load 1703 and power module 1702 determines the current path and, therefore, the power loss. Power module 1702, including inductor module 140, is significantly shorter than conventional power modules. Therefore, in the embodiment of FIG18 , the shorter power module is positioned closer to load 1703, shortening the current path and reducing power loss.

While the present invention has been described with reference to several exemplary embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Because the present invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above-described embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope of the appended patent claims. All changes and modifications coming within the scope of the appended patent claims or their equivalents are intended to be covered by the appended patent claims.

140: Inductor module

150: Power module

203: Power device chip

208: Components

1501: PCB base plate

1502: PCB top plate

Claims (16)

A power module comprises: At least one inductor module, each comprising a magnetic core and two coils passing through the core; A printed circuit board (PCB) top plate positioned above the at least one inductor module; and At least one pair of power device chips positioned above the PCB top plate, wherein each pair of power device chips is positioned above the corresponding inductor module on the PCB top plate, and at least one pin of each power device chip is connected to a corresponding coil of the corresponding inductor module through the PCB top plate; Each inductor module is encased in a plurality of metal sheets, wherein the metal sheets are configured as a power pin and a signal pin for connecting the PCB top plate to a circuit board on which the inductor module is located. A power module as described in claim 1, wherein in each inductor module, each coil has a first end and a second end, wherein the first end of the coil is led to a top of the inductor module, and the second end of the coil is led to a bottom of the inductor module, wherein the top of the inductor module is covered by the PCB top plate. A power module as described in claim 1, wherein the signal pin is distributed on a first side and a second side of the inductor module, wherein the first side and the second side are opposite to each other and parallel to a length direction of the coil of the inductor module. A power module as described in claim 3, wherein in each inductor module, the signal pin located on the first side of the inductor module is connected to the power device chip near the first side, and the signal pin located on the second side of the inductor module is connected to the power device chip near the second side. A power module as described in claim 1, wherein a maximum height of each inductor module measured from a lower surface of the inductor module to an upper surface of the inductor module is 3 mm. The power module of claim 1, wherein at least one of the power pins is configured to receive an input voltage of the power module. A power module as described in claim 1, wherein at least one of the power pins is configured to receive a reference ground voltage of the power module. A power module as described in claim 1, wherein at least one of the power pins is configured to receive a power voltage to power the power device chips. A processor system includes the power module of any one of claims 1-8, further comprising: a motherboard; a load located on the motherboard; and a top cooling system located above the load and the power module; wherein, the power module is located on the motherboard near the load and is configured to supply power to the load. An inductor module comprises: a magnetic core including at least one channel; at least one coil, each passing through the at least one channel corresponding to the magnetic core; and a plurality of metal sheets covering the magnetic core, wherein each metal sheet is C-shaped and wraps around a portion of the side surface of the magnetic core, and has a first end and a second end, wherein the bent first end covers a portion of the top of the magnetic core, and the bent second end covers a portion of the bottom of the magnetic core. The metal sheets are configured as a power pin and a signal pin. An inductor module as described in claim 10, wherein each coil has a first end extending to a top of the inductor module and a second end extending to a bottom of the inductor module. The inductor module as described in claim 10, wherein the signal pin is distributed on a first side and a second side of the inductor module, wherein the first side and the second side are opposite to each other and parallel to a length direction of a coil of the inductor module. The inductor module as described in claim 10, wherein a height measured from a lower surface of the inductor module to an upper surface of the inductor module is at most 3 mm. The inductor module of claim 10, wherein at least one of the power pins is configured to receive an input voltage of a power module configuring the inductor module. An inductor module as described in claim 10, wherein at least one of the power pins is configured to receive a reference ground voltage of a power module configured to configure the inductor module. The inductor module as described in claim 10, wherein at least one of the power pins is configured to receive a power voltage to power a power device chip of a power module configured with the inductor module.