Packaging structure, application and manufacturing method of half-bridge power module

Abstract

The invention discloses a packaging structure of a half-bridge power module. The packaging structure comprises an insulating heat-conducting plate, a multi-layer circuit board, a plastic packaging body and a bridge arm switch, on the other hand, the invention discloses application of the packaging structure of the half-bridge power module in a vehicle-mounted OBC power converter, a DCDC isolation converter, a non-isolation power converter, a cardiac arrest wake-up device and a circuit module formed by combining multiple half bridges such as ANPC, TNPC and Heric. The invention further discloses a manufacturing method of the packaging structure of the half-bridge power module. The manufacturing method comprises the steps of assembling, arranging the overflow area and synchronously filling and grinding to remove the overflow area. The minimum size and low impedance are achieved through the DBC, flexible pin outgoing and welding are achieved through the PCB, the reliability, safety and heat dissipation of the module are supported through the plastic package body, and the expansion temperature monitoring unit and the decoupling capacitor are supported.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics, and in particular to a packaging structure of a half-bridge power module, which is applied in vehicle power supplies, industrial power supplies, medical power supplies, etc., and a manufacturing method thereof. Background Art

[0002] Traditional small and medium power supply designs mostly use standard single-tube packages, such as TO247 plug-in, TO263 patch, etc. Mix and match according to the system application to form different circuit topologies and structural layouts.

[0003] At present, single-tube devices are limited by their own packaging form and standard size, and it is difficult to help further improve the power density of the system end. The existing technology first introduces a single-tube packaging form with top heat dissipation, which can take into account power density and heat dissipation to a certain extent, but there are still problems such as large size, long loop path, inflexible pin method, and difficult insulation treatment;

[0004] In order to cope with some specific applications, the industry has proposed some new forms of half-bridge power modules that can solve some problems under the single-tube packaging form.

[0005] The second aspect of the prior art proposes a top heat dissipation package with power and signal pins led out from the side. The lead-out form of this package solidifies the pin definition, and the size specification is relatively single and lacks flexibility. The pins extend to both sides, resulting in an increase in the loop path, a small safety distance from the heat sink, and the need for additional insulation treatment.

[0006] On the third aspect, the prior art also proposes that the pins adopt the straight-insertion form, and the power and signal pins can be directly led out from the vertical direction, which is more flexible in form than the pins on both sides. But in fact, it is limited by the layout of the power devices on the substrate. Once the design is solidified, the lead-out method is also locked. Adjustments on the system side must accommodate the pin-out method. In addition, straight-insertion pins often require the use of PTH welding technology, through-holes pass through each layer of PCB, and avoid safety distances, which will occupy a larger PCB area and affect the system PCB design utilization rate. The package also needs to be installed by leading out the press-fit terminals on both sides, and installed by screw press-fitting. The overall size is relatively large, and stress will be generated on the pins of the module during installation. Summary of the invention

[0007] In view of this, one of the objects of the present invention is to provide a packaging structure of a half-bridge power module, by breaking the whole into parts, using the circuit structure of the half-bridge as a common circuit unit in various circuit applications, and optimizing the small core of the common circuit unit to the extreme and then further combining it, wherein at least two chips and an optimized electrical connection and heat dissipation structure are packaged in the small core, thereby reducing the overall size of the circuit application module and optimizing its performance.

[0008] To achieve the above-mentioned object, the first aspect of the present invention provides a packaging structure of a half-bridge power module, comprising an insulating heat-conducting plate, a multi-layer circuit board, a packaging filling body and a bridge arm switch, wherein the bridge arm switch comprises an upper bridge arm switch and a lower bridge arm switch, wherein the upper bridge arm switch and the lower bridge arm switch respectively comprise at least one power element, wherein the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface;

[0009] The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit, and the packaging filling body fills the area between the insulating heat-conducting plate and the multi-layer circuit board and covers the bridge arm switch;

[0010] The pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

[0011] Preferably, the pin pads also include NC pads, NC pads being non-connected pads. NC pads do not participate in routing inside the package structure, but can be electrically connected to other pads or to circuits outside the package structure in a fan-out form.

[0012] Preferably, the power pad includes a half-bridge positive pad, a half-bridge negative pad and a half-bridge midpoint pad; the half-bridge positive pad is electrically connected to one end of the half-bridge circuit, and the half-bridge negative pad is electrically connected to the other end of the half-bridge circuit; the circuit node between the upper arm switch and the lower arm switch of the same half-bridge circuit is the half-bridge midpoint end, and the half-bridge midpoint pad is electrically connected to the half-bridge midpoint end.

[0013] Preferably, the pad surface has a first edge, a second edge, a third edge and a fourth edge which are adjacent to each other in sequence; the half-bridge midpoint end pad is arranged near the first edge and is adjacent to the second edge and the fourth edge; the half-bridge negative end pad is arranged near the third edge and is adjacent to the second edge and the fourth edge; the half-bridge positive end pad is arranged between the half-bridge midpoint end pad and the half-bridge negative end pad and is adjacent to the second edge and the fourth edge.

[0014] Preferably, at least two half-bridge circuits are arranged in the packaging structure; on the pad surface, the pin pads are arranged in an array along the first direction according to the corresponding relationship between the half-bridge circuits, and the pin pads are arranged along the second direction according to the circuit function correspondence between the half-bridge midpoint pad, the half-bridge positive pad and the half-bridge negative pad; the half-bridge positive pads corresponding to the half-bridge circuits are arranged in the same row along the first direction, and the half-bridge negative pads corresponding to the half-bridge circuits are arranged in another same row along the first direction.

[0015] Preferably, at least one of the pin pads is a grid-shaped pad, and each of the grid-shaped pads includes a plurality of sub-pads arranged in an array and electrically connected to each other in the packaging structure.

[0016] Preferably, the signal loop pads are arranged in pairs or groups, each pair or group of signal loop pads are arranged in a pad surface sub-area or share a pad surface sub-area with a power pad; each power pad is arranged in one or more pad surface sub-areas; the number of pad surface sub-areas provided with pin pads accounts for at least two-thirds of the total number of all pad surface sub-areas.

[0017] Preferably, each pad surface area is provided with a pin pad, and the area of ​​the pin pad in each pad surface area accounts for no less than 15%.

[0018] Preferably, the power electrodes of the bridge arm switches are electrically connected through the multi-layer circuit board, so the bridge arm switches only need to be fixed on the insulating heat conductive plate by heat conductive glue, and the power electrodes are arranged on the side facing the multi-layer circuit board.

[0019] Preferably, the pin pad further comprises a Sink pad, the Sink pad is electrically connected to the heat dissipation surface, and the Sink pad is used to electrically connect the heat dissipation surface and an electrostatic potential.

[0020] Preferably, the insulating heat conductive plate is a copper-clad ceramic substrate; the upper bridge arm switch and the lower bridge arm switch corresponding to the same half-bridge circuit are respectively arranged on a group of switch copper-clad areas on the insulating heat conductive plate, the switch copper-clad areas include an upper switch copper-clad area and a lower switch copper-clad area, the upper bridge arm switch is electrically connected to the upper switch copper-clad area, and the lower bridge arm switch is electrically connected to the lower switch copper-clad area; the upper switch copper-clad area and the lower switch copper-clad area are adjacently arranged, and the corresponding edges of the upper switch copper-clad area and the lower switch copper-clad area are serrated and zigzag when they are adjacently arranged.

[0021] Preferably, the packaging structure further comprises an electrical connection column, both ends of which are electrically connected to the insulating heat conductive plate and the multilayer circuit board respectively; the packaging filling body covers the electrical connection column; and at least one of the electrical connection columns is located at a tooth-shaped zigzag setting.

[0022] Preferably, the multilayer circuit board is a first PCB board, and the insulating heat-conducting board is a second PCB board; the second PCB board includes at least two wiring layers and at least one insulating medium layer; the thermal conductivity of the insulating medium layer of the second PCB board is greater than 1.

[0023] Preferably, the bridge arm switch includes at least one of a MOS switch, an IGBT element with an anti-parallel diode, a thyristor and a DIO diode.

[0024] Preferably, the bridge arm switch is a third-generation semiconductor device, that is, at least one of a SiC device and a GaN device. Since the packaging structure provided by the present invention has high space utilization, the advantage of the small size of the third-generation semiconductor device can be brought into full play. In the future, when the technology further develops and the fourth or even fifth generation semiconductor devices appear, the volume of the packaging structure can be further reduced to match the packaging resistance and the Rdson of the device.

[0025] Preferably, the bridge arm switch is a vertical device, and the upper surface (towards the insulating heat conductive plate) and the lower surface (towards the multi-layer circuit board) of the vertical device are respectively provided with power electrodes with different electrical properties. The upper surfaces of the two devices are welded to the conductive wiring layer on the surface of the insulating heat conductive plate to achieve electrical and thermal interconnection at the same time, and the wiring layer of the insulating heat conductive plate and the wiring layer of the multi-layer circuit board are electrically interconnected by means of electrical connection columns, etc., and the power pole on the upper surface of the device is led to the module electrode. The electrical connection columns corresponding to the upper surfaces of the two devices are placed in the area between the two devices to reduce the size of the module.

[0026] Preferably, the packaging structure further comprises an active temperature signal element, the active temperature signal element is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad comprises a temperature signal pad;

[0027] The active temperature signal element includes a temperature measurement unit, a signal processing unit, an output enable unit and an output switch device; one end of the temperature measurement unit is set to be grounded; the temperature measurement unit, the signal processing unit, the output switch device and the temperature signal pad are connected in series in sequence; the output switch device has a first end, a second end and a control end, the first end is electrically connected to the output end of the signal processing unit, and the second end is electrically connected to the temperature signal pad; the output enable unit controls the control end by comparing the potentials of the first end and the second end.

[0028] Preferably, the packaging structure also includes a temperature-sensitive Zener diode, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad; one end of the Zener diode is set to be grounded, and the other end is electrically connected to the temperature signal pad.

[0029] The purpose of setting the above-mentioned active temperature signal element or temperature-sensitive Zener diode (collectively referred to as temperature signal element) is that when multiple package structures are used in parallel, the corresponding temperature signal elements can be set in parallel in the external circuit (i.e., the temperature signal pads that output the temperature signal are electrically connected to the same parallel circuit node), so that the output of the temperature signal corresponds to the highest temperature in each package structure. When the package structures provided with the active temperature signal element are used in parallel, the corresponding active temperature signal elements can be connected in parallel. When the package structures provided with the temperature-sensitive Zener diode are used in parallel, the parallel circuit nodes of each temperature signal pad in the external circuit can be electrically connected to the power supply voltage terminal (VCC terminal) through a pull-up resistor.

[0030] Preferably, a packaging filling groove is opened at the edge of the multilayer circuit board; and the packaging filling body fills the packaging filling groove.

[0031] Preferably, a creepage bulge or a creepage groove is provided on the side of the packaging filling body.

[0032] Preferably, the side surface of the packaging filling body is provided with a creepage protrusion or a creepage groove with a horizontal extension length not less than 1 mm, and the actual creepage distance growth value generated is twice the horizontal extension length.

[0033] Preferably, the thickness of the exposed part of the side of the multilayer circuit board does not exceed 1mm. Since the CTI constant of the general packaging filler can reach 400 or even 600 or more, reducing the thickness of the exposed part of the side of the multilayer circuit board will correspondingly increase the proportion of the surface of the packaging filler in the creepage distance of the module side. When the module thickness is the same (for example, 4mm) and the side creepage distance is the same, the voltage resistance performance of the device can be further improved, so that the device can work in the application scenario with a DC voltage upper limit of 800V or even more than 1200V.

[0034] Preferably, a thick thermally conductive metal layer is further provided on the bottom surface of the insulating thermally conductive plate, and the encapsulating filling body covers the side surfaces of the thick thermally conductive metal layer.

[0035] Preferably, the packaging structure further comprises a fixing column, two ends of which are fixedly connected to the insulating heat-conducting plate and the multi-layer circuit board respectively.

[0036] Preferably, the insulating heat conductive plate is divided into four quadrants in the horizontal direction, namely, left front, left rear, right front, and right rear. At least one fixing column is provided between the insulating heat conductive plate and the multilayer circuit board corresponding to each quadrant.

[0037] Preferably, the multilayer circuit board is electrically connected to the fixed column and the power element respectively through welding, the height of the fixed column is Hpole, the sum of the thickness of the power element and its front electrode is Hdie, Hdie-Hpole≥20μm, because the smaller the welding distance of the power element, the smaller the parasitic parameters of the loop, and the height tolerance of the welding surface needs to be considered during welding, so setting the height of the fixed column slightly lower can accommodate more solder here, thereby achieving better tolerance absorption function.

[0038] Preferably, the area of ​​the steel mesh opening corresponding to the solder arranged on the fixing column in the welding process is not less than 120% of the welding area of ​​the top end of the fixing column, so as to arrange more solder on the welding surface.

[0039] Preferably, the total welding area of ​​the top end of the fixing column is not less than 2% of the area of ​​the insulating heat-conducting plate.

[0040] Preferably, the multilayer circuit board includes at least four wiring layers; each of the wiring layers is provided with a DC-wiring area, a DC+ wiring area and a SW wiring area arranged in sequence in one direction, or each of the wiring layers is provided with a DC+ wiring area, a DC- wiring area and a SW wiring area arranged in sequence in one direction; the four wiring layers include a first wiring layer and a second wiring layer, the first wiring layer and the second wiring layer are adjacent, the DC+ wiring area arranged in the first wiring layer is a large-area DC+ wiring area, the DC- wiring area arranged in the second wiring layer is a large-area DC- wiring area, and at least 10% of the projections of the large-area DC+ wiring area and the large-area DC- wiring area overlap with each other.

[0041] Preferably, the packaging structure also includes a plurality of electrical connection columns, both ends of which are electrically connected to the insulating heat conductive plate and the multilayer circuit board respectively; the packaging filling body covers the electrical connection columns; the power element includes at least one vertical power chip; and the electrical connection columns are arranged in parallel between the power elements.

[0042] Preferably, the electrical connection column includes a SW end electrical connection column, the SW end electrical connection column is electrically connected to the SW wiring area, the position corresponding to the SW end electrical connection column in the multi-layer circuit board is an avoidance area, at least one of the DC+ wiring areas is arranged to bypass the avoidance area, or at least one of the DC- wiring areas is arranged to bypass the avoidance area.

[0043] Preferably, when at least one of the DC+ wiring areas is arranged to bypass the avoidance area, the DC+ wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pads corresponding to the DC+ wiring area are long strips spanning the avoidance area; or, when at least one of the DC- wiring areas is arranged to bypass the avoidance area, the DC- wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pads corresponding to the DC- wiring area are long strips spanning the avoidance area.

[0044] Preferably, the packaging structure also includes at least one temperature sampling element, which is arranged in the middle of the upper bridge arm switch and the lower bridge arm switch in the direction of the connection line between the upper bridge arm switch and the lower bridge arm switch, and the temperature sampling element is arranged on one side of the multilayer circuit board in a direction perpendicular to the connection line between the upper bridge arm switch and the lower bridge arm switch.

[0045] Preferably, the power element comprises at least one third-generation power semiconductor element or a low withstand voltage silicon power semiconductor element, or the Rsp of the power element does not exceed 2mOhm / cm 2 , the operating frequency of the board bridge power module is at least 100kHz.

[0046] Preferably, the power element includes at least two planar power semiconductor elements, and the aspect ratio of the planar power semiconductor elements is at least 1.5.

[0047] Preferably, the at least two planar power semiconductor devices are arranged in parallel with their long sides and are interconnected by points to form at least one bridge arm. The multilayer circuit board includes a SW wiring area, a DC+ wiring area and a DC- wiring area, and the SW wiring area is arranged between the DC+ wiring area and the DC- wiring area.

[0048] Preferably, at least one of the DC-wiring area, the DC+wiring area and the SW wiring area is provided with an exhaust hole, and the diameter of the exhaust hole is greater than 0.1 mm.

[0049] Preferably, the packaging structure further comprises at least two bridge arm decoupling capacitors, the bridge arm decoupling capacitors are arranged at positions avoiding the insulating heat conductive plate, and the bridge arm decoupling capacitors are arranged in a straight line.

[0050] Preferably, the power element includes at least four planar power semiconductor elements, and the at least four planar power semiconductor elements are arranged in 2 rows and 2 columns; the packaging structure also includes a temperature sampling unit, and the temperature sampling unit is arranged in the middle position of the at least four planar power semiconductor elements.

[0051] Preferably, the packaging structure further comprises a high-voltage isolation drive component, the high-voltage isolation drive component is arranged on a multi-layer circuit board, and the high-voltage isolation drive component is arranged on one side of the insulating heat-conducting plate and avoids the insulating heat-conducting plate.

[0052] Preferably, the packaging structure further comprises a temperature averaging plate, the temperature averaging plate is arranged on the heat dissipation surface, and the temperature averaging plate is connected to the insulating heat conducting plate with low thermal resistance.

[0053] Preferably, the encapsulated filling body covers the edges of the temperature homogenizing plate on all sides and the coating thickness is at least 0.4 mm.

[0054] Preferably, the packaging structure further comprises a fixing column, two ends of which are fixedly connected to the temperature averaging plate and the multi-layer circuit board respectively.

[0055] Preferably, the temperature homogenizing plate is arranged outside the packaging filling body.

[0056] Preferably, an isolation groove is provided on the pad surface of the multilayer circuit board, the width and depth of the isolation groove are not less than 1 mm, and the isolation groove is used to increase the creepage distance between the high-voltage side and the low-voltage side.

[0057] Preferably, a plurality of the isolation grooves are arranged side by side.

[0058] Preferably, the high-voltage isolation driver assembly includes at least two driver chips; the driver chips are electrically connected via bonding wires, or the driver chips are planar driver chips and the driver chips are electrically connected via a multi-layer circuit board.

[0059] Preferably, the packaging structure further includes an electrical connection column and a current sampling winding, wherein the current sampling winding is provided with at least one turn around the electrical connection column, the current sampling winding is used to sample high-frequency current passing through the electrical connection column, and the current sampling winding is electrically connected to a current sampling circuit.

[0060] Preferably, the current sampling winding is arranged in a multi-layer circuit board, or is preformed together with the electrical connection column to form an assembly.

[0061] Preferably, the current sampling circuit is provided with a correction function.

[0062] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, comprising the following steps:

[0063] Welding a plurality of the packaging structures onto the same PCB substrate;

[0064] A fixed housing and a common heat sink are provided, wherein the fixed housing is used to fix the common heat sink, and the fixed housing includes a cover plate located at the back side of the PCB substrate;

[0065] A pressure ejector pin is arranged between the cover plate and the PCB substrate, and the position of the pressure ejector pin corresponds to the packaging structure;

[0066] The common heat sink is pressed onto a plurality of packaging structures through the fixed shell, and during pressing, the PCB substrate is deformed by the pressure ejector pins so as to absorb the tolerance of each packaging structure in the thickness direction.

[0067] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, comprising the following steps:

[0068] Welding a plurality of the packaging structures onto the same PCB substrate;

[0069] A fixed shell and liquid-cooled radiators corresponding to the number of the packaging structures are provided. The fixed shell is used to press and fix the liquid-cooled radiators and the corresponding packaging structures. The fixed shell includes a heat dissipation liquid pipeline, an interface hose and a pressure elastic member; the interface hose is used to connect the liquid path between the heat dissipation liquid pipeline and the liquid-cooled radiators, so that the heat dissipation liquid pipeline and each liquid-cooled radiator form a connected integral liquid path.

[0070] The liquid-cooled radiator is pressed and fixed on multiple packaging structures through the fixed shell. During pressing, the fixed shell applies pressure in the pressing and fixing direction to the liquid-cooled radiator through the pressure elastic member. The pressure elastic member and the interface hose absorb the tolerance of each packaging structure in the thickness direction through deformation.

[0071] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, and the half-bridge power module is applied to an on-board OBC power converter, wherein the on-board OBC power converter comprises a substrate and at least two of the half-bridge power modules, and at least one power pin between the two half-bridge modules is electrically short-circuited through a system-side multilayer circuit board. The substrate comprises a first component area, a second component area, and a third component area arranged in sequence, wherein the first component area is provided with a capacitor and a controller, the second component area is provided with the half-bridge power module, the heat dissipation surface of the half-bridge power module is provided with a heat sink, the third component area is provided with a transformer and an inductor, the winding of the inductor is integrated in the substrate, or the winding of the inductor is independently heat-dissipated and insulated from the iron core through cavity encapsulation of insulating thermal conductive glue, and the driving component corresponding to the bridge arm switch is arranged on the other side of the substrate corresponding to the half-bridge power module.

[0072] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a DCDC isolation converter, wherein the DCDC isolation converter comprises a substrate, a transformer core and at least one of the half-bridge power modules, wherein the half-bridge power module is an input side module and / or an output side module, the transformer core is buckled on the substrate, the winding corresponding to the transformer core is integrated in the substrate, the input side module and the output side module are respectively arranged on both sides of the transformer core, the heat dissipation surfaces of at least a part of the half-bridge power modules share a heat sink, and an insulating heat conductive member is arranged between the transformer core and the heat sink.

[0073] Preferably, the DCDC isolation converter further comprises a secondary insulation processing structure, and the secondary insulation processing structure is a secondary plastic packaging body or a glue filling structure.

[0074] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a non-isolated power converter, wherein the non-isolated power converter includes a substrate, an inductor element and at least one half-bridge power module;

[0075] The half-bridge power module is arranged on a substrate;

[0076] The inductor element is arranged in parallel with the assembly of the half-bridge power module and the substrate, or the inductor element is arranged in parallel with the half-bridge power module on the substrate;

[0077] The half-bridge power module and the inductor element share a heat sink, and the inductor element and the heat sink are directly provided with insulating heat conducting members.

[0078] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, and the half-bridge power module is applied to a cardiac arrest awakening device, wherein the cardiac arrest awakening device comprises a shell, a first PCBA component layer, a second PCBA component layer and a filling glue, wherein the first PCBA component layer and the second PCBA component layer are stacked in the shell, and the filling glue is filled in the gap between the shell, the first PCBA component layer and the second PCBA component layer; the first PCBA component layer comprises a power supply element and a power supply drive element, and the second PCBA component layer comprises at least one half-bridge power module, and at least one half-bridge power module is used to generate a high-voltage pulse output, and the heat dissipation surface of the half-bridge power module is in contact with the shell.

[0079] Another aspect of the present invention provides an application of the packaging structure of the half-bridge power module, wherein the half-bridge power module is applied to a large IPM module, comprising the following steps:

[0080] The heat dissipation surfaces of the multiple packaging structures are fixedly connected to the heat sink; they are soldered to the first PCB substrate through SMD; module circuit elements are arranged on the other side of the first PCB substrate; the module circuit elements include at least one of a control unit, a driving unit and a decoupling capacitor.

[0081] Preferably, the large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting a plurality of bidirectional switch bridge arms in parallel.

[0082] Another aspect of the present invention provides an application of the packaging structure of the half-bridge power module, wherein the half-bridge power module is applied to a large IPM module, comprising the following steps:

[0083] The heat dissipation surfaces of the plurality of packaging structures are fixedly connected to a heat sink; they are soldered to a first PCB substrate through SMD; a second PCB substrate is provided, and module circuit elements are arranged on the second PCB substrate; the module circuit elements include at least one of a control conductor, a driving unit and a decoupling capacitor; the second PCB substrate and the first PCB substrate are electrically connected through elastic pins.

[0084] Preferably, the large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting a plurality of bidirectional switch bridge arms in parallel.

[0085] Preferably, the method further comprises the following steps:

[0086] Decoupling capacitors are arranged between and outside the packaging structures, and the decoupling capacitors are arranged on the heat sink through a thermal pad and are electrically connected to the first PCB substrate;

[0087] A Vbus capacitor is arranged on the first PCB substrate; the Vbus capacitor is arranged adjacent to the assembly of the decoupling capacitor, the packaging structure and the heat sink.

[0088] Preferably, the method further comprises the following steps:

[0089] A decoupling capacitor and an elastic pin are arranged on a surface of the first PCB substrate facing the second PCB substrate;

[0090] A cover plate is installed on the first PCB substrate, the cover plate covers the decoupling capacitor, and the upper ends of the elastic pins extend out of the cover plate.

[0091] Preferably, the method further comprises the following steps:

[0092] A suspended pad is provided on the surface of the first PCB substrate facing the second PCB substrate, the suspended pad is adjacent to a circuit node pad corresponding to a circuit node corresponding to one pin of a decoupling capacitor, the decoupling capacitor and the suspended pad are electrically connected, and an open circuit is maintained between the suspended pad and the corresponding circuit node pad;

[0093] The leakage current of the packaging structure is tested, and after the test is qualified, the suspended pad is electrically connected to the corresponding circuit node pad.

[0094] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to an ANPC circuit, wherein the ANPC circuit includes a plurality of ANPC sub-units arranged in parallel, wherein the ANPC sub-units include a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, wherein the arm switches of the first half-bridge power module and the second half-bridge power module are both IGBT elements of anti-parallel diodes, and the first half-bridge power module and the second half-bridge power module are connected in series;

[0095] The bridge arm switch of the third half-bridge power module is a MOS switch or an IGBT element of an anti-parallel diode, the half-bridge positive end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the second half-bridge power module.

[0096] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a TNPC circuit, wherein the TNPC circuit includes a plurality of TNPC sub-units arranged in parallel, wherein the TNPC sub-units include a first half-bridge power module and a second half-bridge power module, wherein the second half-bridge power module is a bidirectional switch module, wherein the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the half-bridge positive end pad of the bidirectional switch module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the bidirectional switch module is grounded.

[0097] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, and the half-bridge power module is applied to a Heric circuit, wherein the Heric circuit includes a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, wherein the third half-bridge power module is a bidirectional switch module, and the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the first half-bridge power module and the second half-bridge power module are connected in parallel through a half-bridge positive end pad and a half-bridge negative end pad, and the bidirectional switch module is bridged between the half-bridge midpoint end pad corresponding to the first half-bridge power module and the half-bridge midpoint end pad of the second half-bridge power module.

[0098] Another aspect of the present invention provides a method for manufacturing a packaging structure of a half-bridge power module, comprising the following steps:

[0099] S1: Assemble and fix the insulated heat conducting plate, multi-layer circuit board and bridge arm switch;

[0100] S2: an overflow area is provided below the insulating heat conductive plate, and a space between the insulating heat conductive plate and the multilayer circuit board and the overflow area are simultaneously filled with a packaging filler, so that mold flow impacts of the upper and lower surfaces of the insulating heat conductive plate during packaging filling are offset, and a packaging filling body is formed in the space between the insulating heat conductive plate and the multilayer circuit board and the overflow area;

[0101] S3: removing the packaging filling body in the overflow area by grinding;

[0102] The bridge arm switch comprises an upper bridge arm switch and a lower bridge arm switch, each of the upper bridge arm switch and the lower bridge arm switch comprises at least one power element, the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface;

[0103] The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit.

[0104] Preferably, the pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

[0105] Preferably, the thickness of the packaging filling body in the overflow area is not less than 0.3 mm.

[0106] Preferably, the heat dissipation surface is the back side of an insulating heat conductive plate, and the back side of the insulating heat conductive plate is provided with back side copper cladding. In step S1, the thickness of the back side copper cladding is not less than 150 μm.

[0107] Preferably, step S3 further includes: thinning the back copper coating by grinding.

[0108] Preferably, the front side of the insulating heat conductive plate is provided with front copper cladding. In step S1, the thickness of the front copper cladding is smaller than the thickness of the back copper cladding. The difference between the thickness of the front copper cladding and the thickness of the back copper cladding is at least 50 μm.

[0109] Preferably, after step S3, the thickness tolerance of the packaging structure does not exceed 100 μm.

[0110] The beneficial effects of the present invention are:

[0111] (1) The present invention sets a pad on the top PCB, so that the pins can be directly led from the vertical direction of the power module without leading to the sides, thereby reducing the size of the module and the pin loop path. Each part of the upper surface can be used as a pad area, which has a more flexible pin-out method; and the pad is welded to the system application board through the SMT method, which is easy to produce and implement; by uniformly distributing the pad on the upper surface and controlling the total area, the welding strength is improved, avoiding the risk of SMD solder joint failure caused by displacement due to differences in thermal expansion;

[0112] (2) Only thermal conductive silicone grease needs to be applied between the present invention and the heat sink, and no additional insulation treatment is required, which makes installation easy. In addition, there is no mechanical stress on the pad after installation, and the side of the DBC board facing the module can cooperate with the PCB board to form a 3D packaged electrical connection structure to achieve the smallest size and low impedance. The area utilization rate of this half-bridge module is extremely high. In actual design, for example, 650V 41mOhm and 99mOhm half-bridges, the packaging design of the present invention is adopted, and the total size is only 44% and 30% of the prior art. Since the thickness of the present invention can be used as insulation, it has a larger creepage distance, while ensuring the advantages of insulation, heat dissipation, and high reliability. Compared with the traditional leadframe SMD solution, its thickness utilization rate is at least 1 to 2 mm better, that is, to meet the same insulation requirements, its thickness can be reduced by 1 to 2 mm. This is extremely valuable in the trend of increasingly tight space resources;

[0113] (3) The present invention can take into account the system design of the power module. By modularizing the common circuit unit, namely the half-bridge circuit structure, a set of standard power module design concepts is formed, and it can be compatible with different types of power devices and sizes.

[0114] (4) The present invention strengthens the fixed connection between the insulating heat conductive plate and the multi-layer circuit board through the fixed column or offsets the mold flow impact force through the overflow area, thereby avoiding the problem of solder joint tearing caused by mold flow impact in the packaging filling process; further reduces the parasitic parameters of the module through the wiring setting of the multi-layer circuit board; increases the creepage distance by means of grooving or setting an external convex structure, thereby improving the voltage resistance performance of the module, and can integrate a high-voltage isolation drive component internally, further simplifying the overall module structure when the power module is applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0115] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0116] Figures 1A to 4X is a schematic diagram of Embodiment 1 of the present invention;

[0117] FIG. 5A to FIG. 5C is a schematic diagram of a second embodiment of the present invention;

[0118] Fig. 6A and Fig.6I This is a schematic diagram of Embodiment 3 of the present invention;

[0119] 7A to 7F It is a schematic diagram of the fourth embodiment of the present invention;

[0120] 8A to 9D is a schematic diagram of Embodiment 5 of the present invention;

[0121] FIG. 9E to FIG. 9G is a schematic diagram of Embodiment 6 of the present invention;

[0122] FIG. 10A to FIG. 10B is a schematic diagram of Embodiment 7 of the present invention;

[0123] FIG. 11A to FIG. 11E is a schematic diagram of Embodiment 8 of the present invention;

[0124] FIG. 12A to FIG. 12N is a schematic diagram of Embodiment 9 of the present invention;

[0125] FIG. 13A to FIG. 13G is a schematic diagram of Embodiment 10 of the present invention;

[0126] FIG. 14A to FIG. 14F is a schematic diagram of the eleventh embodiment of the present invention;

[0127] Fig.15 This is a schematic diagram of the twelfth embodiment of the present invention. DETAILED DESCRIPTION

[0128] One of the cores of the present invention is to provide a packaging structure of a half-bridge power module, which uses the circuit structure of the half-bridge as a common circuit unit in various circuit applications by breaking the whole into parts, and optimizing the small core of the common circuit unit to the extreme and then further combining it. The small core encapsulates at least two chips and the most optimized electrical connection and heat dissipation structure, thereby reducing the overall size of the circuit application module and optimizing its performance. Another aspect of the present invention provides the application of the packaging structure of the above-mentioned half-bridge power module.

[0129] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0130] Embodiment 1

[0131] like Figure 1A and Figure 1B The packaging structure of a half-bridge power module disclosed in the present embodiment includes an insulating heat-conducting plate 14 (generally a copper-clad ceramic substrate, i.e., DBC, and the DBC may be provided with metal layers on its upper and lower surfaces), a multilayer circuit board 12 (generally a printed circuit board, i.e., PCB), a plastic package body 13 and at least two bridge arm switches, the bridge arm switches include an upper bridge arm switch and a lower bridge arm switch, the lower surface of the packaging structure is a heat dissipation surface, the upper surface of the packaging structure is a pad surface (a pin pad 11 is provided on the pad surface), and the side surface of the packaging structure is mainly an insulating surface.

[0132] The insulating heat-conducting plate 14 is arranged at the bottom of the packaging structure, the multi-layer circuit board 12 is arranged at the top of the packaging structure, the bridge arm switch is arranged between the insulating heat-conducting plate 14 and the multi-layer circuit board 12, the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit, and the plastic package 13 fills the area between the insulating heat-conducting plate 14 and the multi-layer circuit board 12 and covers the bridge arm switch; Figure 1C As shown, the pads of the half-bridge power module 1 of this embodiment are welded to the customer's mainboard 2 by SMT, which is easy to produce and implement; due to the insulation function of DBC, only thermal conductive silicone grease needs to be applied between the half-bridge power module 1 and the heat dissipation structure such as the radiator (not shown in the figure), and no additional insulation treatment is required, which is easy to install; and the packaging structure of this embodiment reduces the length of the electrical circuit path in the module as much as possible, while maximizing the creepage distance on the side of the module as much as possible.

[0133] Specifically: FIG. 2A to FIG. 2DAs shown, the half-bridge power module includes a half-bridge circuit composed of a first power chipset group (i.e., an upper bridge arm switch, QH) and a second power chipset group (i.e., a lower bridge arm switch, QL), and the power lead of the half-bridge circuit includes a first chip drain (DC+), a half-bridge midpoint end (i.e., a lead formed by the electrical connection between the first power chip source and the second power chip drain, SW), and a second power chip source (DC-); the traditional package has to sacrifice electrical performance and size in order to take into account the internal chip arrangement and external pins of the module. Since the present embodiment uses DBC (i.e., an insulating heat conductive plate 14) and PCB (i.e., a multilayer circuit board 12) 3D packaging to achieve power interconnection, the DBC facing the power chip and the PCB can be provided with an electrical connection structure, so there can be more flexibility to achieve a better arrangement. The first power chip and the second power chip can be placed according to the minimum current path, and the structural diagram is almost the circuit diagram. The leads are short and wide, and the parasitic resistance and inductance are extremely small, which can carry a larger current and a faster switching speed. At the same time, because the footprint of the leads is reduced, the overall size of the DBC is minimized. Multilayer PCB can realize low-loop high-current pin arrangement very well and flexibly. This is equivalent to the internal and external routing of the module getting the optimal solution without mutual trade-offs and sacrifices, truly realizing the best characteristics.

[0134] In a preferred embodiment, the two bridge arm switches of the half-bridge power module are arranged in parallel and close to each other on the DBC to form a DBC power zone from one side to the other, and are electrically interconnected through the DBC or PCB power.

[0135] The power extraction interconnection of the chipset surface electrode is a metal wire or copper clip (collectively referred to as interconnection wire 15). The above interconnection wire can be interconnected with the metal wiring layer on the surface of DBC, that is, first electrically interconnected to the DBC metal wiring layer. Then the DC+, DC-, and SW electrodes are interconnected from DBC to the multi-layer PCB through metal (which can be copper pillars, electroplated holes, etc., collectively referred to as electrical connection pillars 16), and then electrically interconnected from the PCB metal layer to each SMD pad, such as Figure 1D shown.

[0136] In a preferred embodiment, the driving signal is distributed on one or both sides of the DBC power area to form a signal area.

[0137] In a preferred embodiment, the power zones are arranged in the following order: DC+, first power chipset, SW interconnection line, SW copper pillar, second power chipset, DC-interconnection line, DC-copper pillar. This achieves the shortest and smallest area power interconnection. Preferably, the SW copper pillar and the SW lead wire are placed horizontally and crosswise to achieve uniform current distribution.

[0138] In a preferred embodiment, the power lead interconnection of the chipset surface electrode is directly electrically connected to the PCB without transition through the DBC metal layer, and the power interconnection between the two chipsets is the multi-layer metal layer of the PCB. Then the electrodes of the bridge arm switch are first electrically connected through the multi-layer metal layer of the PCB, and after forming a half-bridge circuit, the DC+, DC-, and SW lead terminals are electrically connected to the corresponding SMD pads through the PCB metal layer.

[0139] In a preferred embodiment, the drive signal is also electrically coupled directly to the PCB without transitioning through the DBC metal layer.

[0140] In some other embodiments, the electrical interconnection between the chipset and the PCB may be achieved through copper pillars, solder balls, or copper sheets (collectively referred to as electrical connection pillars 17) on the surface of the chipset. Figure 1E As shown, or, the electrical interconnection between the chipset and the PCB can also eliminate intermediate structures such as the electrical connection column 17 and be achieved directly through electroplating between the chipset surface and the PCB; the direct electrical interconnection between the chipset and the PCB can further reduce the height of the half-bridge power module 1.

[0141] The power chipset can flexibly select chip types. The first power chipset and the second power chipset each contain no less than one chip, and the type can be:

[0142] 1: IGBT contains anti-parallel diode, MOS tube (such as Si MOS, SiC MOS, GaN MOS, etc.); diode or thyristor, etc.

[0143] The power chips can be selected from the same type of devices, or the above devices can be selected and combined as needed. Typically, the same type of devices are selected, such as:

[0144] 1: Half-bridge IGBT with anti-parallel diode - half-bridge A type;

[0145] 2: Half-bridge Si MOSFET; ——Half-bridge B type;

[0146] 3: Half-bridge SiC MOSFET; ——Half-bridge C type;

[0147] 4: Half-bridge GaN MOSFET; ——Half-bridge D type;

[0148] 5: Half-bridge Dio - half-bridge E type;

[0149] Different types of devices can also flexibly select chip specifications, typical specifications such as voltage level 100V ~ 6500V, current 5A ~ 500A;

[0150] Among them, the circuit diagram corresponding to the half-bridge B / C type and the half-bridge power module layout diagram are as follows Figure 2A and Figure 2B As shown, the circuit diagram corresponding to the half-bridge A type and the schematic diagram of the half-bridge power module layout are as follows Figure 2C and Figure 2D As shown, the circuit diagram corresponding to the half-bridge D type is the same as that of the half-bridge B / C type, and the half-bridge power module layout diagram corresponding to the half-bridge D type is as follows Figure 2E shown.

[0151] In some other embodiments, the power chipset may also be a horizontal device, in particular a GaN device.

[0152] In some other embodiments, the half-bridge connection of the chip can be in-phase series connection, or in-phase series connection, or in-phase parallel ....

[0153] In a preferred embodiment, Figure 2F , Figure 2G , Figure 2H As shown, the junction of the two larger copper-clad areas corresponding to the two power chipsets on the DBC, i.e., between the two power chipsets, is usually the middle position of the DBC. The edges of the two copper-clad areas at the junction are zigzag, i.e., toothed edges that bite each other, so that a portion of the copper-clad area is always set at each straight position in the middle of the DBC, thereby increasing the strength of the DBC, improving the bending resistance, and preventing the DBC from breaking during welding or assembly. The electrical connection column 16 can be welded on the copper teeth at the toothed edge, eliminating the space for placing the electrical connection column 16 separately, and further reducing the area of ​​the DBC.

[0154] For applications with low heat dissipation requirements, the DBC can be replaced by a second PCB containing at least two wiring layers and at least one insulating dielectric layer; the thermal conductivity of the insulating dielectric layer is greater than 1, providing thermal conductivity. The outermost wiring layer of the second PCB (i.e., the heat dissipation surface) is an electrostatic potential, that is, electrically connected to the positive end of the half-bridge or the negative end of the half-bridge, reducing the parasitic common-mode capacitance between the half-bridge jump potential end and the heat sink, and reducing common-mode interference. In some applications, such as applying a half-bridge power module to an internal air-cooled power electronic converter, the heat sink is connected to the power ground, and the insulation between the internal components of the module and the heat sink does not require safety insulation.

[0155] In a preferred embodiment, multiple chips are first welded on the DBC, and then the electrical connection pillars 17 and 16 are implanted on the chips and the DBC copper-clad area by welding or electroplating, and then welded to the PCB. When welding the chips, silver sintering method or high-temperature solder with high remelting temperature can be used.

[0156] This embodiment can use SMD LGA pins for easy application. However, after integrating more functions, the size of the half-bridge power module is thicker and larger than that of traditional LGA SMD components. And because the solder is very thin after the SMD pins are soldered to the customer mainboard 2 (generally PCB), usually less than 0.2mm, the displacement caused by the difference in thermal expansion between the module and the customer mainboard 2 during thermal expansion and contraction lacks buffer space, so there is a risk of SMD solder joint failure. In order to improve strength and reliability, this embodiment avoids the above risks by evenly distributing the pads and increasing the total area of ​​the pads.

[0157] The pad surface is equally divided into n×m pad surface sub-areas, where n and m are both greater than or equal to 2, and in this embodiment, n and m are both 3 as an example. The pin pads are evenly distributed in each pad surface sub-area, and the pin pads include the half-bridge positive end pad (corresponding to DC+), the half-bridge negative end pad (corresponding to DC-), the half-bridge midpoint end pad (corresponding to SW) and the signal loop pad (the first power chipset corresponds to HG and HS, and the second power chipset corresponds to LG and LS); the signal loop pads corresponding to the same bridge arm switch are set in the same pad surface sub-area, so there are at least 7 pads in total. In some other embodiments, the signal loop pad may also include a temperature signal pad of a temperature signal element (i.e., an NTC loop pad, at least one pair when set separately, and the embodiment of the half-bridge power module with a temperature signal element is referred to in Example 3), i.e., there are at least 9 pads in total; in some other embodiments, the module does not need to lead out the midpoint end of the bridge arm, and there are at least 6 pads. In some other embodiments, the module half-bridge is in parallel, and there are at least 6 pads.

[0158] Under the condition of meeting the safety distance, the pad pins can be flexibly adjusted according to system requirements, such as Figure 3A As shown, 2 pairs of signal loop pads among the 7 pads are arranged in a left column, and 3 power pads are arranged at the junction of two pad surface areas in the middle and right columns respectively; in some other embodiments, the SW and signal loop pads can also be placed in the same column, opposite to the two sides of the pad column formed by the power pads. In the pad surface area of ​​the nine-square grid divided by the pad surface of the PCB, no less than 5 squares have complete and independent pads or partial pads (at least one-half of the pad surface area), and at this time, it is considered that the pin pads are evenly distributed in each pad surface area to ensure that the mechanical strength of the entire PCB is evenly distributed; the total area of ​​all pads accounts for no less than 15% of the PCB area; in a preferred embodiment, each pad surface area is provided with pads and the area occupied by the pads in each pad surface area is no less than 15% of the pad surface area, and the total area of ​​all pads accounts for no less than 30% of the PCB area.

[0159] In another preferred embodiment, each power pad (DC+ / DC- / SW are collectively referred to as power pads) or paired signal loop pads (signal loop pads corresponding to the bridge arm switch drive loop, signal loop pads corresponding to the temperature signal element, etc., usually arranged in pairs) can also be arranged in the middle of the pad surface area. Sometimes the number of pad surface areas is more than the number of power pads or signal loop pad pairs required to be set, then additional unconnected pads (i.e., NC pads, Non-Connection pads) can be introduced to meet the coverage of the grid. The minimum size of the NC pad is the same as the size of the signal loop pad, such as Figure 3B As shown. Figure 3B In the embodiment shown, the NC pad may not be electrically connected to the metal network to ensure the safety distance between electrodes. In some other embodiments, the NC pad may be further electrically connected to at least one power pad by means of a fan-out metal member, such as Figure 3E and Figure 3F As shown, Figure 3E The NC pads in the middle column are electrically connected to each other and then to an electrostatic pad. Figure 3F Each NC pad in the middle column is electrically connected to a power pad at a corresponding position in the right column.

[0160] In a preferred embodiment, the power pad can be configured as a whole block or a grid shape (such as 2×2 4 grid pads). Figure 3C and Figure 3D As shown, Figure 3C The medium power pads are in the form of a mix of whole blocks and grids. Figure 3D All power pads in the PCB are grid-shaped pads.

[0161] The pads through which energy flows into and out of the half-bridge power module are collectively referred to as power pads, including the half-bridge positive pad, the half-bridge negative pad and the half-bridge midpoint pad (in some embodiments, the half-bridge midpoint may not participate in the circuit connection so that a corresponding pad is not required or the corresponding pad is left floating), each grid-shaped power pad includes a number of sub-pads, which are short-circuited together by a good electrical conductor inside the packaging structure; from another perspective, the sub-pads short-circuited together by a good electrical conductor inside the module are also considered to belong to the same power pad; the pads through which signals flow into and out of the half-bridge module are collectively referred to as signal loop pads, similarly, each grid-shaped signal loop pad includes a number of sub-pads, which are connected together by a good electrical conductor inside the packaging structure; since the signal loop pads corresponding to the same signal inflow and outflow ends are generally arranged adjacent to each other, the signal loop pads are usually arranged in pairs or groups.

[0162] For a pad layout design that meets the safety insulation spacing requirements, on the pad surface, the maximum area allowed for the same power pad to be set or the maximum area allowed for its sub-pad (for grid-shaped pads) to be set is called the power pad area. The maximum area that can be used to place the same pair or group of signal loop pads is called the signal pad area. Power pads or pairs / groups of signal loop pads can be arranged in any shape and any number of pads or sub-pads within their corresponding pad areas. In some embodiments, NC pads are also provided on the pad surface, and the setting area of ​​the NC pads can also be regarded as one or more signal pad areas.

[0163] Since the half-bridge power module needs to be provided with at least one pair / group of signal loop pads and at least two power pads, the pad surface is usually provided with at least one signal pad area and at least two power pad areas. Figure 3G As shown, it includes three power pads (respectively referred to as the first to third power pads) and three pairs / groups of signal loop pads (respectively referred to as the first to third signal loop pads). The length and width of the pad surface are L1 and W1 respectively, the insulation spacing between the first power pad and the first signal loop pad is not less than D1, the insulation spacing between the second power pad and the second signal loop pad is not less than D2, the insulation spacing between the third power pad and the third signal loop pad is not less than D1, the insulation spacing between the first power pad and the second power pad is not less than D3, the insulation spacing between the second power pad and the third power pad is not less than D4, each signal pad area 110 is set to the same width D5, the insulation spacing between the first signal loop pad and the second signal loop pad is not less than D6, and the insulation spacing between the second signal loop pad and the third signal loop pad is not less than D7. The lengths and widths of the first and third power pad regions 111 / 113 corresponding to the first and third power pads are set to be the same. In order to make the area of ​​the second power pad region 112 the same as the areas of the first and third power pad regions, the length and width of each power pad region can be calculated according to the following formula.

[0164] Then the length L2 and width W2 of the first and third power pad regions can be selected as:

[0165] L2 = W1-D1-D5 (1)

[0166] W2=(L1-D3-D4)×(W1-D2-D5) / (3×W1-D1-2×D2-3×D5) (2)

[0167] The length L3 and width W3 of the second power pad area can be selected as:

[0168] L3=W1-D2-D5 (3)

[0169] W3=L1-D3-D4-2×W2 (4)

[0170] The sum L4 of the lengths of the signal pad regions 110 is:

[0171] L4=L1-D6-D7 (5)

[0172] Figure 3H and Fig. 3I Two preferred embodiments designed according to this principle are shown. In this embodiment, each pin pad 11 is a grid-shaped pad. Each pad area is provided with sub-pads (including mandatory pads 11a and optional pads 11b) arranged in an array. In order to reduce the difficulty of the user in designing the wiring of the printed circuit board, the user only needs to weld the mandatory pads 11a corresponding to the hatched pattern in the figure, and the optional pads 11b corresponding to the hollow pattern can be selectively welded. The selection basis of the mandatory pads 11a and the optional pads 11b is as follows: the sub-pads located in the corners of the pad area are mandatory pads 11a, and the sub-pads adjacent to the sub-pads in the corners (excluding diagonally adjacent) are also mandatory pads 11a, and each optional pad 11b is adjacent to at least two mandatory pads 11a (including diagonally adjacent).

[0173] In a preferred embodiment, if Figure 3J As shown, a Sink pad electrically connected to the heat dissipation surface of the module is also provided on the pad surface. The distance between the Sink pad and other surrounding pin pads 11 meets the safety requirements. When using this module, the user can choose to electrically connect the Sink pad to the power pad corresponding to the DC-end or other electrostatic potential ends to reduce the common mode current.

[0174] In a preferred embodiment, in order to facilitate parallel connection of the half-bridge modules, the four edges of the pad surface are defined as the first to fourth edges in sequence, and each power pad area is arranged in sequence along the second and fourth edges of the pad surface, and the second edge and the fourth edge are defined as parallel adjacent edges, and each power pad area is adjacent to each parallel adjacent edge. The same power pad area can be a continuous whole block or multiple discrete blocks, such as Figure 4A , Figure 4B , Figure 4D , Figure 4E As shown, each power pad area is a whole piece, and Figure 4C The following are some embodiments of a power pad area having multiple blocks. Each power pad can be provided with pads or sub-pads of any shape and any number in its corresponding power pad area, such as Figure 4G , Figure 4H , Fig. 4I , Figure 4J An example of a pad area with only one pad is shown.

[0175] In a preferred embodiment, if Figure 4AAs shown, the first power pad is arranged in the first power pad area 111, the second power pad is arranged in the second power pad area 112, and the third power pad is arranged in the third power pad area 113; the pad surface is divided into 3×3 pad surface sub-areas a~i, then the two signal pad areas 110 share the corresponding pad surface sub-areas b and pad surface sub-areas h with the first power pad area 111 and the third power pad area 113 respectively, including the first signal pad area and the second signal pad area; a pair of first signal loop pads are arranged in the first signal pad area, and a pair of second signal loop pads are arranged in the second signal pad area. The insulation spacing between the first power pad area 111, the third power pad area 113 and the signal pad area 110 is not less than D1, the insulation spacing between the first power pad area 111 and the second power pad area 112 is not less than D3, and the insulation spacing between the second power pad area and the third power pad area is not less than D4. The first to third power pad areas 111 / 112 / 113 are centrally symmetrically arranged, and the two signal pad areas 110 are respectively located outside the corresponding first and third power pad areas 111 / 113 (ie, the power pad areas surround the signal pad area 110 on three sides facing outward).

[0176] In another preferred embodiment, Figure 4B As shown, Figure 4A The difference is that the two signal pad areas 110 are respectively located at the inner side of the corresponding first and third power pad areas 111 / 113 (ie, the three sides of the power pad area surround the signal pad area 110 inwardly).

[0177] In another preferred embodiment, Figure 4C As shown, the difference is that the first power pad area is divided into two symmetrical pad areas 111A and 111B, the third power pad area is divided into two symmetrical pad areas 113A and 113B, and a signal pad area 110 is respectively provided between the pad area 111A and the pad area 111B, and between the pad area 113A and the pad area 113B.

[0178] In another preferred embodiment, Figure 4D As shown, the difference is that the first power pad area 111 surrounds the signal pad area 110 on three sides facing inward, and the third power pad area 113 surrounds the signal pad area 110 on three sides facing outward. In other embodiments, it can also be replaced with the first power pad area 111 surrounding the signal pad area 110 on three sides facing outward, and the third power pad area 113 surrounding the signal pad area 110 on three sides facing inward (figure omitted).

[0179] In another preferred embodiment, Figure 4EAs shown, the difference is that one signal pad area 110 and the third power pad area 113 share the sub-areas g to i on the pad surface close to the third edge, that is, the signal pad area 110 is completely arranged outside the third power pad area 113. Another signal pad area 110 can be arranged in the aforementioned embodiment, or can refer to the same layout method of being completely located outside.

[0180] like Figure 4F It is a standard half-bridge topology plus temperature monitoring circuit diagram. The half-bridge positive terminal pad, half-bridge negative terminal pad, and half-bridge midpoint terminal pad correspond to the DC+ terminal, DC- terminal, and SW terminal in the circuit diagram respectively. A pair of signal loop pads correspond to the control signal terminal of the upper bridge arm switch, namely the GH terminal and the SH terminal. The other three signal loop pads correspond to the control signal terminal of the lower bridge arm switch, namely the GL terminal, the SL terminal, and the temperature signal output terminal, namely the SENSE terminal. (Since the temperature monitoring and control signal share the SL terminal, the signal loop pads corresponding to the three signal terminals form a group). In the subsequent Figure 4G to Figure 4O In the diagram, each pin pad is labeled according to its circuit function. Figure 4G yes Figure 4A A specific embodiment of the invention. The first power pad area 111 corresponds to the SW terminal, the GH terminal and the GL terminal are adjacent to the SW terminal on the pad surface, the second power pad area 112 corresponds to the DC+ terminal, the third power pad area 113 corresponds to the DC- terminal, and the GL terminal, the SL terminal and the SENSE terminal are adjacent to the DC- terminal on the pad surface.

[0181] Figure 4H yes Figure 4B A specific embodiment of .

[0182] Fig. 4I yes Figure 4C A specific embodiment of .

[0183] Figure 4J yes Figure 4D A specific embodiment of .

[0184] Figure 4G , Figure 4H , Fig. 4I , Figure 4J The medium power pad area is covered by a whole pad. In some other embodiments, it can also be set to a grid shape, that is, a plurality of small square sub-pad arrays fill the pad area, such as Figure 4K shown.

[0185] In a preferred embodiment, the impedance between any two sub-pads corresponding to the same pin pad 11 is no more than 3 mΩ, so it is not necessary to solder all the sub-pads when in use. Figure 4L As shown, only a portion of the sub-pads corresponding to the shaded pattern in the figure can be welded.

[0186] When multiple half-bridge modules are used in parallel, decoupling capacitors 19 may be placed between the half-bridge modules to reduce switching noise, such as Figure 4M , Figure 4N , Fig.4O As shown, each power pad is adjacent to two parallel adjacent edges (i.e., the second and fourth edges) at the same time, so that the parallel electrical connection routing outside the module can be set to the shortest, and the power pad corresponding to the SW end is set near the first edge of the pad surface, and the power pads corresponding to the DC+ end and the DC- end are set in the middle of the pad surface and near the third edge, which can facilitate the electrical connection of the decoupling capacitor 19. In some other embodiments, the decoupling capacitor can also be integrated into the module, so that when the module is used in parallel, it is not necessary to place capacitors between the modules.

[0187] In a preferred embodiment, Figure 4A , Figure 4B , Figure 4D , Figure 4E Each power pad area and one signal pad area in the embodiment are split into two, respectively, into six pad areas 111A to 113B corresponding to the power pads and three signal pad areas 110, such as Figure 4P As shown, the pad surface is divided into 4×3 pad surface sub-areas a~l, then the pad areas 111A~113B are respectively set in two adjacent pad surface sub-areas, and the three signal pad areas 110 are respectively located in the pad surface sub-areas b, c and j~k. The advantage of this is that the pad surface design is compatible with the full-bridge module. If it is a half-bridge module, the pad area 111A / B is set with the same power pad, the pad area 112A / B is set with the same power pad, the pad area 113A / B is set with the same power pad, the two signal pad areas 110 near the first edge are set with the same pair / group of signal loop pads, and the signal pad area 110 near the third edge is set with the same pair / group of signal loop pads. If it is a full-bridge module, Figure 4R Taking the circuit shown as an example, that is, a packaging structure in which two half-bridge circuits are electrically connected at one end and packaged together, pad area 111A corresponds to SW1 terminal, pad area 111B corresponds to SW2 terminal, pad area 112A / B corresponds to DC+ terminal, pad area 113A corresponds to DC-1 terminal, pad area 113B corresponds to DC-2 terminal, GH1 terminal and SH1 terminal are arranged in signal pad area 110 adjacent to pad area 111A, GH2 terminal and SH2 terminal are arranged in signal pad area 110 adjacent to pad area 111B, and the remaining signal loop pads (corresponding to GL1 terminal, SL1 terminal, GL2 terminal, SL2 terminal, T1 terminal, and T2 terminal) are arranged in signal pad area 110 adjacent to pad area 113A / B, as shown in FIG. Figure 4U As shown. Figure 4STaking the circuit shown as an example, that is, a packaging structure in which two half-bridge circuits are directly packaged together, pad area 111A corresponds to SW1 terminal, pad area 111B corresponds to SW2 terminal, pad area 112A corresponds to DC+1 terminal, pad area 112B corresponds to DC+2 terminal, pad area 113A corresponds to DC-1 terminal, pad area 113B corresponds to DC-2 terminal, GH1 terminal and SH1 terminal are arranged in signal pad area 110 adjacent to pad area 111A, GH2 terminal and SH2 terminal are arranged in signal pad area 110 adjacent to pad area 111B, and other signal loop pads are arranged in signal pad area 110 adjacent to pad area 113A / B, as shown in FIG. Figure 4V As shown. Figure 4T Taking the circuit shown as an example, that is, a packaging structure in which two half-bridge circuits are packaged together in parallel, pad area 111A corresponds to SW1 terminal, pad area 111B corresponds to SW2 terminal, pad area 112A / B corresponds to DC+ terminal, pad area 113A / B corresponds to DC- terminal, GH1 terminal and SH1 terminal are arranged in signal pad area 110 adjacent to pad area 111A, GH2 terminal and SH2 terminal are arranged in signal pad area 110 adjacent to pad area 111B, and the remaining signal loop pads are arranged in signal pad area 110 adjacent to pad area 113A / B, as shown in FIG. Figure 4W shown.

[0188] In another preferred embodiment, the signal pad area close to the third edge is also divided into two, that is, there are four signal pad areas 110 in total.

[0189] The signal pad area 110 can be set at any corner of the adjacent power pad area and surrounded by the power pad area on two sides, or can be set at any edge of the adjacent power pad area and surrounded by the power pad area on three sides. The four signal pad areas 110 can be independently set in relative positions and share pad surface sub-areas a and / or b, c and / or d, i and / or j, k and / or l with the pad areas 111A, 111B, 113A, and 113B respectively. Figure 4Q The example of three signal pad areas 110 being arranged at the corners of the power pad area and one signal pad area 110 being arranged at the edge of the power pad area adjacent to the third edge is shown in FIG. Figure 4R Taking the circuit shown in the figure as an example, the pin definitions corresponding to the circuit functions are as follows Figure 4X As shown. Figure 4S , Figure 4T The example of the circuit shown is similar and will not be repeated here.

[0190] Since the PCB and DBC board in the half-bridge power module of this embodiment can form a more flexible electrical connection route through 3D packaging, the number of circuit layers of the PCB can also be flexibly set according to needs, which can be a double-sided board or a four-sided board or even more, so as to more flexibly allocate the connection path from the bottom pin to the pad.

[0191] Embodiment 2

[0192] The difference between this embodiment and the first embodiment is that in application scenarios such as vehicle scale assembly, the quality of the solder joints needs to be observed after soldering, so the SMD pads need to be partially extended to the side of the module. The PCB of this embodiment can be provided with a hemming, that is, at least one SMD pad extends to the side of the module, such as Figure 5A As shown in the figure, the solder wets the bottom pad and then crawls to the side. When solder is observed on the side, it can be judged that the wetting is good and the welding quality is good.

[0193] Since the side of the half-bridge power module of this embodiment is an insulating surface for insulation and creepage, the side extension 18 of the pad cannot occupy too much height to affect the creepage distance of the module. In a preferred embodiment, the side extension 18 is arranged by setting a depth-limiting hole on the motherboard of the PCB. For example, a hole with a diameter of 0.5 mm and a depth of 0.5 mm is set on a 1 mm thick PCB. In this way, during plastic sealing, the PCB is still sealed and does not affect the plastic sealing. Then, when the board is divided, the depth-limiting hole is cut open to leave a part of the side wall to form the required side extension of the pad. Another way to set the side extension is to set a through hole on the motherboard of the PCB and then fill the hole. In this way, the PCB is also sealed, and the subsequent steps are the same as the previous setting method.

[0194] On the other hand, during the process, the packaging filler (such as plastic compound) has to flow between the DBC and the PCB. The mold flow pressure is very high, which can be as high as 100 atmospheres. When the mold flow flows, it generates an impact between the DBC and the PCB to form an external tearing force, causing the solder joints connecting the two to be torn.

[0195] In this embodiment, a plurality of fixing columns 161 are disposed between the DBC and the PCB. The two ends of the fixing columns 161 are strongly connected to the PCB and DBC structures, and the two are held together during injection molding to prevent the solder joints from tearing. In this embodiment, there are requirements for the distribution position and density of the fixing columns 161. In the horizontal direction, at least one fixing column 161 is disposed in each of the module parts corresponding to the left front, left rear, right front, and right rear quadrants of the DBC. The fixing columns 161 can be formed by structural members with a certain strength, such as copper columns. The total welding area of ​​the fixing columns 161 is not less than 2% of the area of ​​the DBC, preferably not less than 5%, to ensure sufficient pulling force to resist the impact of mold flow. In some embodiments, it can also play an electrical connection role at the same time, that is, it is disposed as the electrical connection column 16 in the first embodiment. As Figure 5BAs shown, when the fixing column 161 is welded with other electronic components, in order to ensure the precision welding of other electronic components, the height Hpole of the fixing column 161 should be less than the height of other components (for example, the sum of the thickness of the power chip and the electrodes on its front side Hdie), and the difference between the two is more than 20μm, preferably, 50μm, so that more solder can be set on it to absorb the tolerance, so that the steel mesh used for welding can be thin, and the precision welding of other components such as the power chip can be achieved. The welding of the fixing column 161 can achieve sufficient solder volume by expanding the opening area of ​​the steel mesh, for example, expanding to more than 120% of the welding area of ​​the top of the fixing column 161, preferably, more than 150%. On the other hand, in order to ensure that the packaging filler completely fills the gap between the electrodes and ensures the structural safety of the power chip, if the front of the power chip is directly welded to the PCB by means of conductive balls or the like (that is, the case where the electrical connection column 17 in the first embodiment is a conductive ball), the diameter of the conductive ball can be set to be not less than 0.2mm, preferably, not less than 0.3mm. It should be noted that, in this embodiment, the power chip has a side facing the electrically insulating heat conductive plate as the back side, and a side facing the PCB as the front side.

[0196] In another preferred embodiment, the impact of mold flow pressure can also be offset by improving the manufacturing process. Figure 5C As shown, during the process of package filling, a channel with a thickness of at least 0.3mm (preferably at least 0.5mm) is reserved under the heat dissipation surface of the module for mold flow, that is, Hm≥0.3mm, especially Hm≥0.5mm is preferred, so that the mold flow simultaneously generates equal pressure on the upper and lower surfaces of the DBC, offsetting each other, reducing the external tearing force between the DBC and the PCB and leaving an overflow area 131 on the heat dissipation surface. Obviously, the overflow area 131 needs to be removed by grinding after the package filling; in addition, in some precision scenes, the heat dissipation surface of the DBC needs to be ground after the module is plastic-sealed, ensuring that the flatness of the heat dissipation surface is better than 100μm, and there is also an opportunity to achieve a total thickness tolerance of the module of less than 50μm, then there is a requirement for the thickness of the copper-clad surface on the back of the DBC, that is, the copper-clad surface on the back of the DBC is further thickened compared to the copper-clad area on the front. In order to ensure the smooth progress of grinding, the thickness of the copper-clad surface on the back of the DBC is not less than 150μm, preferably, not less than 250μm. At the same time, in order to ensure the etching accuracy of the DBC copper clad area, its thickness is set to be smaller, for example, 50μm or even 100μm thinner than the copper clad surface on the back.

[0197] Embodiment 3

[0198] One difference between this embodiment and the first embodiment is that a concave or convex structure is provided on the side of the plastic package 13; on the other hand, this embodiment further includes a temperature signal element and / or a decoupling capacitor 19 and / or a gate drive chip, such as Fig. 6A and Figure 6BPreferably, the temperature signal element / decoupling capacitor 19 / gate driver chip is placed on the side of the PCB facing the chip to reduce the interconnection between the DBC and the PCB. If the temperature signal element / decoupling capacitor 19 / gate driver IC is higher than other chips, the copper clad area corresponding to the position of its projection on the DBC can be reduced in thickness by etching or other methods, or even completely removed to avoid space.

[0199] Since the thickness of the half-bridge power module 1 is relatively small, the insulating surface of a simple planar structure may not meet the requirements of the side creepage distance required by the safety regulations. Therefore, a groove may be cut on the side of the plastic package 13 to increase the creepage distance. The groove position may be set continuously around the plastic package 13, or may be set only in a part of the side wall area close to the outer pad, such as Fig. 6A As shown; in another preferred embodiment, a convex circle around the plastic package 13 can also be provided to increase the creepage distance. The convex position can be provided continuously around the plastic package 13, or it can be provided only in a part of the side wall area close to the outer pad, such as Figure 6B shown.

[0200] In a preferred embodiment, if Figure 6G As shown, increasing the thickness of the PCB can further increase the side creepage distance of the half-bridge power module. Considering that the leakage tracking index of the plastic encapsulation material is higher than that of the PCB board, the PCB can be grooved at the edge (for example, a fixed depth groove is opened on the PCB motherboard, and the board can be divided along the fixed depth groove), and the plastic encapsulation material is filled during plastic encapsulation to increase the proportion of plastic encapsulation material on the side of the half-bridge module. The vias in the thickened PCB can also use thick copper technology to improve its temperature resistance and conductivity. Since the CTI constant of the PCB is usually less than 200, while the plastic encapsulation material can reach 400 or even more than 600, the higher the proportion of the plastic encapsulation material on the side wall of the module, the stronger the pressure resistance of the module. Specifically, the total thickness of the module should be no less than 3mm, preferably no less than 4mm; and the thickness of the exposed part of the side wall PCB should be no more than 1mm, especially preferably no more than 0.5mm, so that more thickness is left for the plastic encapsulation material with a larger CTI constant.

[0201] In a preferred embodiment, if Fig.6I As shown, the above Fig. 6A / Figure 6B Examples and Figure 6GThe embodiment is combined. The protrusion or creepage groove of the side wall is arranged at the position of the side wall plastic material, so that the increased distance is the plastic material with a larger CTI, so that it can withstand an operating voltage of 800V or even higher. The length of the protrusion extending outward (or the creepage groove extending inward) should be no less than 1mm, which is equivalent to an increase in the creepage distance of no less than 2mm. The above-mentioned setting of increasing the creepage distance is generally used in scenarios where the DC voltage upper limit is not less than 800V, and preferably the DC voltage upper limit is not less than 1200V.

[0202] In a preferred embodiment, if Figure 6H As shown, a thicker layer of good thermal conductor (collectively referred to as a thick thermal conductive metal layer) is welded on the back of the DBC (i.e., the bottom of the half-bridge power module) by silver sintering 25 or high-temperature soldering, and then plastic-sealed. The plastic sealing body 13 covers the side of the silver sintering 25, which can increase the side creepage distance of the half-bridge module.

[0203] In some other embodiments, the creepage distance may be increased simply by retracting the pads on the front side of the PCB or the copper clad surface on the back side of the DBC.

[0204] In a preferred embodiment, the temperature signal element is active, so that when multiple temperature signal elements are connected in parallel, only the one with the highest temperature is output. Figure 6C As shown, the active temperature signal element is composed of a temperature measuring unit 20, a signal processing unit 21, an output enabling unit 23 and an output switch 22. The temperature measuring unit 20 can be implemented by materials such as a thermistor, a thermocouple, a photosensitive material, a PN junction, etc., and the signal amplifying unit 21, the output enabling unit 23 and the output switch 22 are all composed of semiconductor devices. Fig.6D The invention is a preferred embodiment of using a positive temperature coefficient thermistor as the temperature measuring unit 20 and an N-channel metal oxide transistor as the output switch 22. The signal processing unit 21 uses an operational amplifier to amplify the signal, and the output enabling unit 23 controls the output switch 22 by comparing the voltage signals at both ends of the output switch 22. Fig. 6E The figure shows the situation where multiple temperature signal elements are used in parallel. For the module with the highest temperature signal voltage value, the output enable unit 23 maintains the conduction of the corresponding output switch 22; and for the module with a lower temperature signal voltage value, the output enable unit turns off the corresponding output switch 22 by comparing the voltage values, thereby achieving the output of only the temperature signal of the module with the highest temperature.

[0205] In a preferred embodiment, the temperature signal element in the module includes a temperature measuring unit 20, and the temperature measuring unit 20 uses a temperature-sensitive Zener diode with a negative temperature coefficient, such as Fig. 6FWhen there are multiple modules, the user only needs to connect the temperature signal output terminals of each module in parallel and pull them up with the pull-up resistor 24 to know the highest temperature of all modules.

[0206] Embodiment 4

[0207] This embodiment mainly describes the application of the half-bridge power module in the vehicle-mounted OBC power converter 101. Fig. 7A , the on-board OBC (including single-phase charger and three-phase charger) mainly includes the above functional blocks and related auxiliary modules such as sampling and protection logic. Usually due to the differentiation of the whole vehicle architecture, the layout of the body and core components are different, resulting in different shapes of chargers, and it is impossible to form a set of modular design concepts. Through the half-bridge power module proposed in this embodiment, the minimized design of the core power module (i.e., the on-board OBC power converter 101) can be achieved, thereby solidifying the core power module, and only by adjusting the peripheral interface circuit, it is necessary to meet the application requirements of different OEMs for the component form.

[0208] The current typical single-phase on-board charger and three-phase on-board charger circuit diagram, such as Figure 7B and Figure 7C As shown, by replacing the individual bridge arm circuits from scattered components with the half-bridge power module 1 proposed in this embodiment, the occupied area of ​​the power device can be effectively reduced, the loop path can be effectively reduced, the use of insulating sheets can be reduced, the process complexity can be reduced, and the reliability can be improved.

[0209] In addition to the vehicle-mounted OBC power converter 101 , the application of this embodiment can also be applied to realize other non-vehicle-mounted high power density AC to DC power converter module applications.

[0210] like FIG. 7D to FIG. 7F As shown, the vehicle-mounted OBC power converter 101 includes a substrate 3 and at least two half-bridge power modules 1. The substrate 3 includes a first component area 31, a second component area 32 and a third component area 33 which are arranged in sequence. The first component area 31 is provided with a capacitor 5 and a controller 4, the second component area 32 is provided with a half-bridge power module 1, the heat dissipation surface of the half-bridge power module is provided with a heat sink 7, the third component area 33 is provided with a magnetic element 6 (also provided with a power factor correction chip PFC, the magnetic element 6 in this embodiment is the magnetic core of the transformer), and the driving component 41 corresponding to the bridge arm switch is arranged on the other side of the substrate 3 corresponding to the half-bridge power module.

[0211] Specifically, the half-bridge power module includes an SMD half-bridge power module, a multi-layer PCB substrate 3, and related peripheral circuits and magnetic components 6. The power semiconductor module is SMD soldered on the substrate 3, and the magnetic component 6 is horizontally placed on the side and electrically interconnected to the substrate 3. The surface of the magnetic component 6 and the half-bridge power module on the same side may have an electrically insulating heat-conducting cover / pad, that is, the heat-conducting surface of the magnetic component 6 and the half-bridge power module is on the same side of the substrate 3 and is installed together on the same heat sink 7. Only thermal conductive silicone grease needs to be applied to the surface of the heat sink 7, and no additional insulation treatment is required.

[0212] In this embodiment, the converter is an isolated ACDC, the magnetic element 6 can be a transformer and an inductor, and at least one of its input power semiconductor and output power semiconductor uses the SMD power semiconductor module of this embodiment, which can be a half-bridge A, half-bridge B, half-bridge C, half-bridge D, half-bridge E or a combination thereof.

[0213] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules 1 and are placed on the left and right sides of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0214] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules 1 and are placed on the same side of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0215] In a preferred embodiment, the input and output power semiconductors are both half-bridge power modules 1 and are placed on the upper and lower surfaces of the substrate 3 respectively. The half-bridge power modules below the substrate and the lower surface of the magnetic element 6 are installed on the same surface of the heat sink 7, and the half-bridge power modules above the substrate and the upper surface of the magnetic element 6 are pressed together with the upper heat sink to achieve double-sided heat dissipation of the converter module.

[0216] In a preferred embodiment, the transformer winding can be composed of a plurality of PCB copper layers of the substrate 3, achieving extremely high power density and automated production.

[0217] In a preferred embodiment, the transformer winding may be formed by winding a magnetic core and an independent coil, and electrically interconnected with the substrate 3 by hard wire or welding.

[0218] In some other embodiments, the converter module capacitor, control chip and its peripheral circuits can be placed on one side of the power module, taking into account distance and routing smoothness, while being separated from the high and low voltage areas of the module to avoid interference; preferably, the converter's drive component 41 and controller 4 can be placed on the back of the power module, connected to the power module by the minimum path.

[0219] In some other embodiments, the magnetic components can be independently arranged through the cavity to achieve a certain shielding effect, and the upper and lower surfaces are in close contact with the shell or the heat dissipation surface to ensure heat dissipation.

[0220] Embodiment 5

[0221] This embodiment mainly describes the application of the half-bridge power module in the DCDC isolation converter. FIG. 8A to FIG. 8C As shown, the DCDC isolation converter includes a substrate 3, a transformer core (i.e., a magnetic element 6) and at least one half-bridge power module 1, wherein the half-bridge power module 1 is arranged on the substrate 3; the transformer core is arranged in parallel with the assembly of the half-bridge power module and the substrate, or the transformer core and the half-bridge power module are arranged in parallel on the substrate; the half-bridge power module and the transformer core share a heat sink 7, and an insulating heat conductor 71 is arranged between the transformer core and the heat sink.

[0222] Specifically, the half-bridge power module includes an SMD half-bridge power module, a multi-layer PCB substrate 3 and its related peripheral circuits, and a magnetic component 6 .

[0223] The power semiconductor module SMD is soldered on the substrate 3 , and the magnetic element 6 is horizontally placed on the side and electrically interconnected to the substrate 3 . The heat conducting surface of the magnetic element 6 and the half-bridge power module are on the same surface of the substrate 3 and are installed together on the same heat sink 7 .

[0224] In this embodiment, the converter is an isolated DCDC, the magnetic element 6 may be a transformer, and at least one of the input power semiconductor and the output power semiconductor thereof uses the SMD power semiconductor module of the present invention.

[0225] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules and are placed on the left and right sides of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0226] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules and are placed on the same side of the transformer core to achieve uniform heat distribution and power output pins on the left and right sides of the converter module.

[0227] In a preferred embodiment, the input and output power semiconductors are both half-bridge power modules and are placed on the upper and lower surfaces of the substrate 3 respectively. The heat dissipation surfaces of each half-bridge power module are the same as the heat dissipation surfaces of the magnetic element 6 and are installed on the same heat sink surface to achieve double-sided heat dissipation of the converter module.

[0228] In a preferred embodiment, the transformer winding is composed of a substrate 3 and a plurality of PCB copper layers, achieving extremely high power density and automated production.

[0229] In some other embodiments, the surface on the same side of the magnetic element 6 and the half-bridge power module has an electrically insulating thermally conductive cover / pad (i.e., an insulating thermally conductive member 71). The electrically insulating thermally conductive cover / pad material is an easily deformable buffer material that absorbs the displacement tolerance between the heat dissipation surface of the magnetic element 6 and the heat dissipation surface of the half-bridge power module, thereby ensuring a good connection between the half-bridge power module as a high thermal density component and the heat sink.

[0230] The module structure of this embodiment has the following advantages:

[0231] 1) Semiconductors with the highest heat density require excellent heat dissipation channels;

[0232] 2) This embodiment has a built-in multi-layer PCB, which can reduce the number of layers required for the substrate 3 PCB. By using the SMD application method, the module can be directly placed in the overlapping area above the winding of the magnetic element of the PCB, and the number of layers of the substrate 3 is almost not increased;

[0233] 3) The internal laminated structure fully utilizes the PCB component height space created by the thickness of the magnetic element 6 core.

[0234] In some other embodiments, such as FIG. 9A to FIG. 9B As shown, Fig. 9A and Fig. 9B The difference lies in the different packaging structure of the half-bridge power module 1. The DCDC isolation converter also includes a secondary insulation treatment structure, which is a secondary plastic package 8 or a glue filling structure. The secondary insulation treatment structure can also be applied to other embodiments of the present invention where secondary insulation treatment is required.

[0235] Since the thickness of the half-bridge power module 1 can be very thin, such as 3 to 5 mm, and the built-in DBC enables it to have the ability to resist safety insulation. However, the creepage distance from the electrode to the heat sink through the side is basically determined by the thickness of the module, making it difficult to directly adapt to the scenario of excessively high safety insulation, such as up to 12 to 18 mm. The system application and related products mentioned in the present invention can also be secondary packaged, so that the creepage distance between the module electrode and the heat dissipation surface is formed by solid insulation of the packaging filler. Mainly: at least one half-bridge power module 1 is SMDed together with at least one other component on a system PCB board to form a PCBA. All components on one side of the PCB where the half-bridge power module 1 is installed are completely immersed in the secondary packaging material together with the PCB surface to achieve solid insulation.

[0236] In some other embodiments, the secondary packaging may be plastic packaging, which can further enhance strength and reliability. Preferably, polishing is performed after plastic packaging to ensure the flatness of the heat dissipation surface of each module and to ensure that multiple modules are in thermal contact with the heat sink at the same time.

[0237] In some other embodiments, such as Fig. 9C As shown, the glue filling structure is an insulating glue 9 of silica gel or epoxy glue, and is constrained by a shell 91 on the outside. The shell 91 can directly dissipate heat to the outside, and other radiators 7 can also be further installed.

[0238] In a preferred embodiment, the housing is preformed and then placed into the PCBA and then filled with glue.

[0239] In a preferred embodiment, if Fig.9D As shown, the housing 91 includes an annular retaining wall 92 and a sealing adhesive 93. The glue filling structure is configured in such a way that the PCBA is first thermally bonded to the heat sink 7, and after the annular retaining wall 92 is electrically insulated, the annular retaining wall 92 is bonded to the heat sink 7 through the sealing adhesive 93, and then the insulating glue 9 is filled.

[0240] In a preferred embodiment, the PCBA has power pins for external connection, and at least a portion of the power pins is directly or indirectly led out of the sealed housing.

[0241] In a preferred embodiment, the PCBA is also stacked with another PCBA and electrically interconnected to add more functions.

[0242] In a preferred embodiment, the upper surface of the chip inside the half-bridge power module 1 is directly electrically welded to the PCB inside the module, thereby realizing an ultra-thin half-bridge power module with a thickness thinner than 4 mm.

[0243] Embodiment 6

[0244] This embodiment mainly describes the application of the half-bridge power module in a non-isolated power converter. Fig.9E As shown, the non-isolated power converter includes a substrate 3, a magnetic element 6 and at least one half-bridge power module 1; the half-bridge power module 1 is arranged on the substrate 3; the magnetic element 6 is arranged in parallel with the assembly of the half-bridge power module 1 and the substrate 3, or the magnetic element 6 is arranged in parallel with the half-bridge power module 1 on the substrate 3; the half-bridge power module 1 and the magnetic element 6 share a heat sink 7, and an insulating heat conductor 71 is arranged between the magnetic element 6 and the heat sink 7.

[0245] Specifically: a power module of the non-isolated power converter includes an SMD half-bridge power module 1, a multi-layer PCB substrate 3 and its related peripheral circuits, and a magnetic component 6. The half-bridge power module is soldered on the substrate 3 through SMD, and the magnetic component 6 is horizontally placed on the side and electrically interconnected to the substrate 3. The surface of the magnetic component 6 on the same side as the half-bridge power module 1 can have an electrically insulating thermal conductive cover / pad (i.e., an insulating thermal conductive member 71), so that the thermal conductive surface of the magnetic component 6 and the half-bridge power module 1 are on the same surface of the substrate 3 and are almost flush, so that they can be installed together on the same heat sink 7.

[0246] In this embodiment, the non-isolated power converter can also be DCDC or ACDC or DCAC, and its power semiconductor uses at least one power module of this embodiment. The lower surface of the PCB is a half-bridge power module 1, and the upper surface is small components such as ceramic capacitors 42 to form PCBA. The magnetic element 6 in this embodiment is illustrated using an inductor as an example.

[0247] In a preferred embodiment, the inductor element is a copper-iron preformed element, which is placed on the side of the PCBA and electrically connected.

[0248] In a preferred embodiment, if Fig.9F As shown, the inductor element is a copper-iron preformed element, the thickness of which is equivalent to that of the half-bridge power module 1, and is soldered on the same side of the PCB together with the half-bridge power module.

[0249] In a preferred embodiment, if Figure 9G As shown, the winding or part of the winding of the inductor element is the wiring layer of the PCB. The inductor magnetic material has a part on the upper and lower surfaces of the PCB.

[0250] Embodiment 7

[0251] This embodiment mainly describes the application of the half-bridge power module in the cardiac arrest awakening device 102. Fig. 10A and Fig. 10B As shown, the cardiac arrest awakening device 102 includes a shell 91, a first PCBA component layer, a second PCBA component layer and an insulating glue 9. The first PCBA component layer and the second PCBA component layer are stacked in the shell, and the filling glue is filled in the gap between the shell, the first PCBA component layer and the second PCBA component layer; the first PCBA component layer includes a power supply element 102a and a power supply drive element 102b, and the second PCBA component layer includes at least one half-bridge power module, and the at least one half-bridge power module is used to generate a high-voltage pulse output, and the heat dissipation surface of the half-bridge power module is in contact with the shell; the cardiac arrest awakening device 102 also includes a magnetic element 6 (specifically an inductor) and a release resistor 102c, and the magnetic element 6 and the release resistor 102c can be set on the first PCBA component layer or the second PCBA component layer as needed.

[0252] Specifically: The cardiac arrest awakening device includes at least one half-bridge power module (with a built-in high-voltage switch bridge arm for converting high-voltage DC into high-voltage pulses) placed on one side of a PCB, and the driver of the half-bridge power module is set on the other side of the PCB, together forming a main PCBA. The main PCBA is provided with power pins for electrical connection with the outside. The PCBA is placed in a shell and filled with silicone or epoxy glue, submerging almost the entire PCBA to achieve high-voltage insulation.

[0253] In some other embodiments, a secondary PCBA is stacked with the main PCBA and electrically connected to the main PCBA, and both are submerged in the colloid to achieve more functions.

[0254] Preferably, the secondary PCBA may be provided with a high-voltage isolation power supply low-voltage input low-voltage output DCDC converter required by the half-bridge power module driver, and the two PCBAs may be connected through internal pins for power supply.

[0255] In a preferred embodiment, the secondary PCBA may also be provided with a low-voltage-input and high-voltage-output DCDC converter, which converts an external low-voltage DC power supply into a high-voltage DC and then provides it to a bridge arm placed in a half-bridge power module to convert it into a high-voltage pulse, and then provides it to an external connection through a power pin or even stimulates the human body to wake up the heart.

[0256] In a preferred embodiment, the main and auxiliary PCBAs are provided with choke inductors connecting the high voltage direct current and the bridge arm.

[0257] In some other embodiments, the housing 91 is a good thermal conductor, such as a metal shell.

[0258] In a preferred embodiment, a release resistor for releasing the energy of a capacitor storing high voltage DC energy when not needed is in thermal contact with the housing, thereby expanding the heat dissipation capacity of the release resistor and reducing its volume.

[0259] In a preferred embodiment, the metal shell is connected to the GND of the external low-voltage input to achieve overall shielding.

[0260] In some other embodiments, since the pulse voltage is as high as several thousand volts, its common mode noise can easily interfere with complex wake-up calculations. The metal layer of the heat dissipation surface of the half-bridge power module can be electrically connected to a static ground potential, such as a potential that does not jump relative to the battery GND, to achieve a common mode shielding effect and reduce common mode interference.

[0261] In some other embodiments, due to the discontinuity of cardiac pacing, the half-bridge power module is heat treated only by the heat capacity of its structural material system. To reduce the risk of unnecessary short circuits, the heat dissipation surface of the module can be covered with at least 0.4 mm of plastic packaging material.

[0262] The size of the high-voltage generating core component of the cardiac pacemaker of this embodiment is greatly reduced from the original 12cm×6cm×2.4cm to 6cm×5mm×2cm, which greatly reduces the size of the entire awakening device, and patients are more willing to carry it with them, which can save more lives and is of great significance.

[0263] Embodiment 8

[0264] This embodiment mainly describes the application of half-bridge power modules in IPM large modules, that is, multiple half-bridge power module small units are SMD-welded to the same surface of a multi-layer PCB conversion board 11, and each heat dissipation surface is almost flat, such as FIG. 11A to FIG. 11B As shown. The other side of the PCB can be flexibly placed with large module pins, drivers, capacitors, inductors, conductive screw holes, fixing screw holes, etc. The upper and lower surfaces of the PCB edge can even be placed with gold finger pins to reduce cost and size. Copper bars and other power connectors can also be embedded. In addition, secondary filling glue process can also be performed on one side of the PCB module side (such as Fig.11A The insulating glue 9 shows the position), which greatly increases the creepage distance.

[0265] The internal contents of each module can be exactly the same, for example, two half-bridge sub-modules form a full bridge, and three half-bridge sub-modules form a three-phase bridge.

[0266] Modules with different contents can also form more types of circuit units: for example, a high-voltage half-bridge module plus a double-tube back-to-back series module (the back-to-back series bridge arm circuit is regarded as a special case of the half-bridge circuit in the present invention) forms a TNPC circuit unit. For example, two IGBT half-bridge modules plus a SiC half-bridge module form an ANPC circuit unit.

[0267] The components of the above modules can also be connected in parallel to form a larger half-bridge power composite module. Multiple circuit units can also be connected in parallel to form a higher-power high-voltage electronic switch.

[0268] In some scenarios with particularly high heat density, especially those with relatively large transient power, extreme heat dissipation capability is required. Therefore, it is recommended that the heat dissipation surface of each module sub-unit of this embodiment be hardened onto the heat sink through a material with excellent thermal conductivity, such as Fig. 11B As shown, for example, a metal sintering process is used, such as silver sintering 25. However, after this, if the module is still SMD to the PCB conversion board, the upper and lower surfaces of the module are hard-connected, and in some cases there is a lack of stress buffering, resulting in reliability risks. Therefore, the module can be prefabricated with pins with strong buffering capabilities and then soldered to the conversion board.

[0269] In a preferred embodiment, Fig. 11CAs shown, at least two half-bridge power modules 1 are welded on a substrate 3, and a decoupling capacitor 19 is placed close to the half-bridge power module 1 to reduce the electrical loop area between the decoupling capacitor 19 and the half-bridge power module 1. A film capacitor 26 (i.e., Vbus capacitor) is placed close to the decoupling capacitor 19 to reduce the electrical loop area between the decoupling capacitor 19 and the film capacitor 26. An insulating heat conductor 71 with high thermal conductivity is provided between the decoupling capacitor 19 and the heat sink 7 to prevent the decoupling capacitor 19 from overheating. The PCB conversion board 27 where the control and drive are located is pressed to the substrate 3 through elastic pins 28 to provide stress buffering, realize low-loop, low-assembly challenge, high-reliability interconnection, and flexibly match the drive. The edge of the substrate 3 is connected to the outside world using gold finger pins or embedded copper bars.

[0270] Packaging multiple modules and capacitors into an integrated module will pose a challenge to leakage current testing. During the test, the sum of leakage current and capacitor charging current may be measured. To solve this problem, the capacitor can be connected in parallel to the leakage current test loop before testing the leakage current. Fig.11D For example, one pin of the decoupling capacitor 19 is electrically connected to the suspended pad 29, and after the leakage current test is passed, the suspended pad 29 and the pad corresponding to DC+ are welded. Fig.11D When the decoupling capacitor 19 is disposed on the back side of the substrate 3, the pin of the decoupling capacitor 19 can be directly welded to the suspended pad 29; and when the decoupling capacitor 19 is disposed adjacent to the half-bridge power module 1, one pin of the decoupling capacitor 19 can also be electrically connected to the suspended pad 29 through a via or the like.

[0271] Fig.11E The manufacturing process of packaging multiple modules, capacitors, and liquid cooling radiators together is shown. First, the half-bridge power module 1 and the annular retaining wall 92 are fixed on the radiator 7 (the half-bridge power module 1 can be fixed by welding or glue with high thermal conductivity, and the annular retaining wall 92 is fixed by glue), then the substrate 3 is welded, and then the decoupling capacitor 19 is welded (if the decoupling capacitor 19 is set in the vicinity of the half-bridge power module 1, follow Fig. 11C Corresponding descriptions adjust the corresponding steps) and the elastic pin 28. This step can be carried out according to the aforementioned method to first measure the leakage current and then fully connect the decoupling capacitor 19 to the circuit. After welding, install the cover plate 94 to seal it into a whole. Plastic sealing can be selected, and finally install the heat dissipation liquid pipeline corresponding to the radiator 7.

[0272] Embodiment 9

[0273] This embodiment mainly describes the application of half-bridge power modules to form a more complex circuit structure; Fig. 12AAs shown, since the half-bridge power module needs to be used in multiple combinations, its pins must take into account the convenience of application combination use. Therefore, the pads with different functions need to be set in rows. Take m as 4 as an example, that is, 4 rows of pad surface areas, and the corresponding pad functions from the first row to the fourth row are: signal (drive), DC-, DC+, SW. Since switches with the same function may be composed of multiple components in parallel, the number of pad columns can be set accordingly according to the number of components in parallel.

[0274] In a preferred embodiment, if Fig. 12B and Fig. 12C As shown, three half-bridge power modules 1 form a three-phase bridge circuit, and the DC+ pads and DC- pads of the three half-bridge power modules 1 are electrically connected to the same DC+ terminal and the same DC- terminal, respectively, and the u terminal, v terminal, and w terminal are respectively led out (corresponding to the midpoint ends of the bridge arms of the three half-bridge power modules 1, respectively), that is, each dotted box area in the figure is electrically connected to the same end.

[0275] In a preferred embodiment, if Fig.12D and Fig.12E As shown, three half-bridge power modules 1 are arranged in parallel to form a power expansion, and the u terminal, the v terminal, and the w terminal can be further electrically connected to the same SW1 terminal on the basis of the three-phase bridge circuit structure.

[0276] In a preferred embodiment, if Fig.12F and Figure 12G As shown, Figure 12G The framed area with the same shading indicates that the pads in the area are electrically connected to the same end. The ANPC circuit requires two modules: a SiC MOS half-bridge and an IGBT half-bridge. Each half-bridge corresponds to a half-bridge power module 1 (different types of half-bridges correspond to modules with different types of bridge arm switches). Two IGBT modules can be placed up and down to form an IGBT three-level bridge, and then left and right with the SiC bridge to form a complete ANPC circuit sub-unit ( Figure 12G The rounded dashed box shown represents an ANPC circuit subunit).

[0277] Since the power of the ANPC circuit is relatively large, three half-bridge power modules 1 may form an ANPC circuit sub-unit, and then the ANPC circuit sub-units may be arranged in parallel, thus achieving extremely small loop inductance.

[0278] In a preferred embodiment, the TNPC circuit also requires two modules: a half-bridge and a bidirectional switch. The pad layout of the half-bridge power module 1 corresponding to the bidirectional switch is as follows: Fig.12HAs shown, the half-bridge power module 1 does not need to lead out the midpoint end of the bridge arm, and the two ends of the bridge arm are marked as SW1 and SW2 respectively. After placing it in parallel with the half-bridge power module, a TNPC circuit subunit is formed, in which the circuit diagram and the electrical connection relationship of the pads are as follows Fig.12I and Fig.12J As shown ( Fig.12J The rounded dashed box in the figure represents a TNPC circuit subunit).

[0279] Since the power of the TNPC circuit is relatively large, multiple TNPC circuit sub-units can be arranged in parallel relative to each other, thus achieving extremely small loop inductance.

[0280] In a preferred embodiment, if Figure 12K and Figure 12L As shown, the Heric circuit also requires two sub-modules: a half-bridge and a bidirectional switch. A Heric circuit unit includes a half-bridge power module 1 corresponding to two half-bridge circuits and a half-bridge power module 1 corresponding to a bidirectional switch. The full bridge can be formed by placing two half-bridge modules in parallel, and then combined with the bidirectional switch module.

[0281] In some other embodiments, a solid-state relay circuit may be formed by connecting a plurality of bidirectional switch half-bridge power modules 1 in parallel.

[0282] In the above application, multiple half-bridge power modules 1 are used, and these half-bridge power modules 1 are welded together on a PCB (substrate 3) to form the required functions. However, due to the module thickness tolerance and welding thickness tolerance, when multiple half-bridge power modules 1 are pressed onto the same heat sink 7, the gaps on the thermal contact surfaces are inconsistent, and the heat dissipation is poor due to the large gaps, leading to the risk of overheating. If screw holes are set near each half-bridge power module 1 to press the substrate 3 and the heat sink 7, the deformation of the substrate 3 made of PCB material can be effectively used to absorb the gap tolerance and ensure the heat dissipation safety of each half-bridge power module 1. However, the pad stress at the corners of the pad surface of each half-bridge power module 1 is relatively large.

[0283] To solve this problem, in a preferred embodiment, Figure 12M As shown, each half-bridge power module 1 is provided with at least one pressure pin 95 (which may be in the shape of a pin or a block), which is pressed against the back side of the substrate 3 (the side where the half-bridge power module 1 is welded is the front side), and the contact point between the pressure pin 95 and the substrate 3 corresponds to the center position of the pad surface of the half-bridge power module 1. When the heat sink 7 is fixed by the housing 91, the cover plate 94 applies pressure to the substrate 3 through the pressure pin 95, so that the substrate 3 is deformed to absorb the gap tolerance. Preferably, the substrate 3 can be provided with some vias at the positions corresponding to the gaps between the modules to improve the plasticity of the PCB.

[0284] In another preferred embodiment, Fig.12NAs shown, a heat sink 7 that can independently adapt to tolerances is configured for each module. When the housing 91 is installed, the radiator 7 will automatically fit the module through the pressure spring 96, and the heat dissipation liquid channel inside the (liquid-cooled) radiator 7 is connected to the heat dissipation liquid pipeline in the housing 91 through an interface hose 97. When the radiator 7 adapts to the tolerance, the interface hose 97 is deformed accordingly; at this time, the substrate 3 does not need to be deformed, and there is no need to configure ejector pins / ejector blocks, so that more space can be used to place components on the substrate 3.

[0285] The switch disclosed in the present invention can be Si MOSFET, SiC MOSFET, GaN MOSFET or IGBT or Dio, etc., all of which can realize the function of the switch disclosed in the present invention.

[0286] Embodiment 10

[0287] This embodiment mainly discloses a multi-layer PCB wiring layer layout for achieving lower bridge arm loop inductance in a packaging structure of a half-bridge power module. Fig.13A As shown, the bridge arm loop inductance is parasitic in the loop formed by the bridge arm (the bridge arm includes the upper bridge arm switch QH and the lower bridge arm switch QL connected in series) and the capacitor C across the DC+ and DC- ends corresponding to the bridge arm. The power chip corresponding to the bridge arm switch is set inside the module; and the capacitor C can be set inside the module or outside the module, but no matter which one, the wiring layer layout of the PCB needs to minimize the loop area formed by the bridge arm switch itself.

[0288] To achieve this goal, Fig. 13B As shown, the PCB of this embodiment is provided with at least four wiring layers, which are respectively as follows from left to right: the first layer is the device layer, the second and third layers are the inner layers, and the fourth layer is the Pad layer. At least one of the four layers is provided with a large-area DC-wiring area, and at least one layer is provided with a large-area DC+wiring area, and the two layers are adjacent layers, so that the large-area DC-wiring area and the DC+wiring area overlap by at least 10% of their area, providing a high-frequency current coupling channel and reducing loop inductance.

[0289] When the device corresponding to the built-in power chip of the module is a vertical device, that is, there are power electrodes on both the front and back of the power chip, it is necessary to set an electrical connection column 16 to electrically connect the power electrode from the metal layer on the upper surface of the DBC to the device layer of the PCB. Since the backs of the two power chips are usually not at the same potential, for example, they correspond to the DC+ end and the SW end respectively, at least two electrical connection columns 16 are required. The two electrical connection columns 16 are placed side by side and parallel between the two power chips to minimize space waste, make the module size small, and reduce the current path and loop inductance. The vertical device is preferably SiC. In a preferred embodiment, the power chip size is a SiC power chip of about 5mm*5mm, with a withstand voltage of 1200V and an Rdson of less than 15mOhm. Through the structural settings disclosed in this embodiment and the aforementioned embodiments, a total size of less than 16*10*4(H)mm can be achieved, which is suitable for a half-bridge module with an operating frequency of not less than 100kHz, preferably not less than 500kHz, and even a frequency applicability of up to 1MHz. The volume is less than one-third of existing products, and the loop inductance is less than one-fifth of existing products, which can greatly improve the performance of SiC.

[0290] Most of the wiring layers are divided into at least three wiring areas, which are arranged up and down in sequence, with DC+ between SW and DC- (in some other embodiments, DC- may also be between SW and DC+), so that the DC+ wiring area and the DC- wiring area are adjacent to each other, providing convenience for the overlap of the two.

[0291] To enhance the DC+ and DC- overlap, vias are provided at both ends of the DC+ wiring area to connect to each layer, especially the Pad layer, so that DC+ and DC- not only have enough overlap area, but also the current flow in the overlap area is uniform. At the same time, each welding position of the long DC+ Pad area is low impedance away from the inside of the module, reducing the difficulty of system layout.

[0292] Since the module disclosed in this embodiment is applicable to high-frequency scenarios, it is also necessary to reduce the parasitic capacitance between SW and DC+ or DC-, so the internal wiring of the multi-layer PCB board should avoid SW and DC+ or DC- overlapping. Specifically, at least one inner layer of the multi-layer PCB should leave an avoidance area at the position corresponding to the electrical connection column 16 at the SW end to avoid DC+ and SW overlapping, and the DC+ wiring area sets the vias between the layers on both sides of the avoidance area and detours outside the avoidance area.

[0293] In a preferred embodiment, the module contains at least one temperature sampling device TS. To facilitate wiring and ensure the temperature sampling effect, the temperature sampling device TS is placed on one of the left and right sides of the PCB and in the middle of the upper and lower parts, that is, in the middle of the two adjacent power chips.

[0294] Since the module of this embodiment is highly integrated and the PCB is subjected to multiple high-temperature resistant welding during the module production process and use, the large-area wiring area of ​​the inner layer of the multi-layer PCB is provided with exhaust holes, that is, multiple openings with a diameter greater than 0.1 mm are provided, preferably with a diameter greater than 0.2 mm, to facilitate the release of moisture inside the PCB and avoid explosion.

[0295] The embodiment of the present invention in which the front side of all power chips is directly electrically connected to the PCB (the electrical connection distance from the chip electrode to the PCB is no longer than 1 mm is called direct connection) is particularly suitable for Rsp less than 2mOhm / cm 2 Especially less than 1mOhm / cm 2 The device is currently a third-generation semiconductor SiC or GaN, or a Si device with a withstand voltage lower than 100V. In the future, there may also be fourth- and fifth-generation semiconductors, etc., which can reduce the package resistance to match the device Rdson. The embodiment of the present invention also reduces the distributed parameters and increases the operating frequency. The operating frequency of the module of the embodiment of the present invention is preferably not less than 100KHz, especially not less than 500KHz.

[0296] In another preferred embodiment, Fig. 13C As shown in the figure, for planar devices, that is, devices with all power electrodes on the front of the power chip, such as GaN. The length of the planar device is usually more than 1.5 times the width to achieve lower chip internal resistance. The source S and drain D are set along the long side, while the gate G and source S are adjacent. Fig.13D , Fig.13E and Fig.13FThe metal layer layout and chip setting (top view), PCB device layer layout (bottom view) and PCB Pad layer layout (top view) of a full-bridge module are shown. In order to reduce the loop inductance, the two power chips forming the bridge arm are arranged in parallel with the long side, and the power electrodes between the two power chips are interconnected to form the SW electrode. Therefore, in the device layer, the wiring area is arranged in the order of DC+, SW, and DC-, that is, the SW wiring area is between the DC+ wiring area and the DC- wiring area. The Pad arrangement of the module can also correspond to the order of the PCB device layer wiring area, reducing the power routing path and the parasitic capacitance between the SW end and the DC+ end / DC- end. However, in this way, it is more difficult for the DC+ end and the DC- end to be coupled through the wiring layer to reduce the parasitic inductance, and the switching speed of the planar device is usually very fast, and it requires a lower loop inductance than the vertical device. Therefore, it is more meaningful to have a built-in loop decoupling capacitor (capacitor C). Capacitor C should be a small-sized device as much as possible and set up multiple devices. In order to reduce the size of the capacitor C, multiple capacitors C should be arranged in a linear array along the length or width direction, that is, only one of the width or length should be increased as small as possible. If multiple switch bridge arms are provided in the half-bridge power module 1, the number of capacitors C can be set to be at least one more than the number of switch bridge arms. Since the bridge arm decoupling capacitor is a high-voltage capacitor, the size is often relatively large, and the area where it is placed needs to avoid DBC, such as Figure 13G As shown, at least 50% of the capacitor C and DBC do not overlap in the vertical direction.

[0297] When the module is a single half-bridge arm, the temperature sampling device TS can be placed near the outside of the SW wiring after the two bridge arm chips are interconnected. When there are multiple bridge arms in the module, the temperature sampling device TS is set in the middle of the four devices in 2 rows and 2 columns. As a specific embodiment, the chip size of 650V 50mOhm is about 3mm*1.5mm, the DBC size of the full bridge is about 10mm*8mm, and the final size of the module is about 14mm*12mm, so it is extremely small, less than one-third of the existing solution.

[0298] Embodiment 11

[0299] This embodiment discloses a structure of a power module that integrates an isolation driver nearby. Due to its small size, a high-voltage isolation driver can be directly integrated. FIG. 14A to FIG. 14CAs shown, in order to reduce the difficulty of packaging, the driving component 41 is only placed on the multi-layer circuit board 12 (i.e., PCB), and is not directly connected to the insulating heat conductive plate 14 (i.e., DBC). Therefore, the driving component 41 should be arranged outside the DBC in the horizontal direction. Then the area of ​​the DBC will be significantly smaller than the size of the module. Therefore, in actual use, a temperature equalizing plate 141 with an area equivalent to that of the module can be connected to the DBC with low thermal resistance by welding or bonding with high thermal conductivity materials. The temperature equalizing plate 141 is surrounded by the plastic package 13, and the width of the edges of the temperature equalizing plate 141 from the surface of the plastic package 13 is not less than 0.4mm to ensure that the plastic packaging material around the temperature equalizing plate can be included in the creepage distance. As shown Fig.14A As shown, if the temperature plate 141 is first connected to the DBC and then plastic-sealed, then the fixing column 161 needs to be provided to increase the strength and resist mold flow. In some other embodiments, the DBC and the PCB can also be connected and plastic-sealed first, and then the temperature plate 141 can be provided.

[0300] Since the size of devices from the third generation onwards is very small, the module size can also be small, so the creepage distance of the high-voltage drive will become an obstacle to reducing the module size. Fig. 14B and Fig. 14C As shown, in this embodiment, on the pad surface of the PCB, between the high-voltage side and the low-voltage side Pad, a mature PCB fixed-depth groove process is used to prefabricate an isolation groove 121 with a width and depth of not less than 1 mm to increase the creepage distance. Preferably, as Fig.14D As shown, a plurality of isolation grooves 121 may be arranged in parallel to further increase the creepage distance.

[0301] This embodiment is particularly suitable for use in high-voltage isolation transformers. Fig.14E and Fig.14F As shown, a high-voltage isolation transformer, at least a part of the transformer winding is integrated in a system PCB, a half-bridge power module 1 is welded on the system PCB and placed on the high-voltage side, the system PCB is provided with an opening, and a magnetic core is placed in a buckled manner, the height of the magnetic core above the system PCB is similar to the thickness of the half-bridge power module 1, and the magnetic coupling with the winding realizes power conversion. After applying the half-bridge power module 1 of this embodiment, the heat dissipation surface of the power device on the high-voltage side is concentrated and regular. If the height of the magnetic core is designed to match the thickness of the half-bridge power module 1, the fixing of the heat sink 7 of the converter is much simpler and more reliable than the traditional solution. Since the heat sink 7 can be directly thermally connected to the magnetic core and the low-voltage side without insulation or only low-voltage insulation is required, and the half-bridge power module 1 also has built-in high-voltage isolation, the system almost does not require insulation treatment when installing the heat sink, and can achieve extremely high reliability and heat dissipation capacity.

[0302] Even if some low-heat devices (small heat sources) are not integrated, it is easy to achieve heat conduction through traditional means, such as setting a thermal pad 72 and an insulating thermal conductive member 71. When the thickness of the half-bridge power module 1 meets the requirements of the side creepage distance, such as Fig.14E As shown, the heat sink 7 and the half-bridge power module 1 can be directly thermally connected using low-voltage and low-thermal resistance materials; when the thickness of the half-bridge power module 1 does not meet the requirements of the side creepage distance, such as Fig.14F As shown, the heat sink 7 and the half-bridge power module 1 can be thermally connected via an insulating heat-conducting member 71 that complies with safety regulations.

[0303] Embodiment 12

[0304] In this embodiment, the power electrode on the back of the power chip is guided from the DBC to the PCB through the electrical connection column 16, or the front electrode of the power chip is raised through the electrical connection column 17 to facilitate mold flow entry. Fig.15 As shown, when a high-frequency current flows through at least one of the electrical connection column 16 and the electrical connection column 17, current sampling integration can be achieved by setting a current sampling winding 30 around the electrical connection column 16 / 17. In a preferred embodiment, the current sampling winding 30 can be formed by prefabricating the winding on the electrical connection column 16 / 17, or by etching the welding surface around the electrical connection column 16 / 17 on the PCB, and then the current sampling winding 30 is electrically connected to a current sampling circuit (set in an independent chip or integrated with other circuits) to process the sampling signal. The current sampling circuit can be provided with a correction function, and the sampling coefficient can be systematically corrected when the power module is factory tested to achieve high-precision sampling.

[0305] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0306] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A packaging structure of a half-bridge power module, characterized in that: It includes an insulating heat-conducting plate, a multi-layer circuit board, a packaging filling body and a bridge arm switch, wherein the bridge arm switch includes an upper bridge arm switch and a lower bridge arm switch, wherein the upper bridge arm switch and the lower bridge arm switch each include at least one power element, wherein the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface; The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit, and the packaging filling body fills the area between the insulating heat-conducting plate and the multi-layer circuit board and covers the bridge arm switch; The pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

2. The packaging structure according to claim 1, characterized in that: The pin pads also include NC pads.

3. The packaging structure according to claim 1, characterized in that: The power pad includes a half-bridge positive pad, a half-bridge negative pad and a half-bridge midpoint pad; the half-bridge positive pad is electrically connected to one end of the half-bridge circuit, and the half-bridge negative pad is electrically connected to the other end of the half-bridge circuit; the circuit node between the upper arm switch and the lower arm switch of the same half-bridge circuit is the half-bridge midpoint end, and the half-bridge midpoint pad is electrically connected to the half-bridge midpoint end.

4. The packaging structure according to claim 3, characterized in that: The pad surface has a first edge, a second edge, a third edge, and a fourth edge that are adjacent to each other in sequence; the half-bridge midpoint end pad is arranged near the first edge and is adjacent to the second edge and the fourth edge; the half-bridge negative end pad is arranged near the third edge and is adjacent to the second edge and the fourth edge; the half-bridge positive end pad is arranged between the half-bridge midpoint end pad and the half-bridge negative end pad and is adjacent to the second edge and the fourth edge.

5. The packaging structure according to claim 3, characterized in that: At least two half-bridge circuits are arranged in the packaging structure; on the pad surface, the pin pads are arranged in an array along the first direction according to the corresponding relationship between the half-bridge circuits, and the pin pads are arranged along the second direction according to the circuit function correspondence between the half-bridge midpoint pad, the half-bridge positive pad and the half-bridge negative pad; the half-bridge positive pads corresponding to the half-bridge circuits are arranged in the same row along the first direction, and the half-bridge negative pads corresponding to the half-bridge circuits are arranged in another same row along the first direction.

6. The packaging structure according to claim 1, characterized in that: At least one of the pin pads is a grid-shaped pad, and each of the grid-shaped pads includes a plurality of sub-pads arranged in an array and electrically connected to each other in the packaging structure.

7. The packaging structure according to claim 1, characterized in that: The signal loop pads are arranged in pairs or groups, and each pair or group of signal loop pads is arranged in a pad surface sub-area or shares a pad surface sub-area with a power pad; each power pad is arranged in one or more pad surface sub-areas; the number of pad surface sub-areas provided with pin pads accounts for at least two-thirds of the total number of all pad surface sub-areas.

8. The packaging structure according to claim 7, characterized in that: A pin pad is arranged in each pad surface area, and the area of ​​the pin pad in each pad surface area accounts for no less than 15%.

9. The packaging structure according to claim 1, characterized in that: The power electrodes of the bridge arm switches are electrically connected via a multi-layer circuit board.

10. The packaging structure according to claim 1, characterized in that: The pin pads also include a Sink pad, which is electrically connected to the heat dissipation surface and is used to electrically connect the heat dissipation surface to an electrostatic potential.

11. The packaging structure according to claim 1, characterized in that: The insulating heat-conducting plate is a copper-clad ceramic substrate; the upper bridge arm switch and the lower bridge arm switch corresponding to the same half-bridge circuit are respectively arranged on a group of switch copper-clad areas on the insulating heat-conducting plate, and the switch copper-clad areas include an upper switch copper-clad area and a lower switch copper-clad area, the upper bridge arm switch is electrically connected to the upper switch copper-clad area, and the lower bridge arm switch is electrically connected to the lower switch copper-clad area; the upper switch copper-clad area and the lower switch copper-clad area are adjacently arranged, and the corresponding edges of the upper switch copper-clad area and the lower switch copper-clad area are serrated and zigzag when they are adjacently arranged.

12. The packaging structure according to claim 11, characterized in that: It also includes an electrical connection column, the two ends of which are electrically connected to the insulating heat-conducting plate and the multi-layer circuit board respectively; the packaging filling body covers the electrical connection column; and at least one of the electrical connection columns is located at the tooth-shaped meandering setting.

13. The packaging structure according to claim 1, characterized in that: The multilayer circuit board is a first PCB board, and the insulating heat-conducting board is a second PCB board; the second PCB board includes at least two wiring layers and at least one insulating medium layer; the thermal conductivity of the insulating medium layer of the second PCB board is greater than 1.

14. The packaging structure according to claim 1, characterized in that: The bridge arm switch includes at least one of a MOS switch, an IGBT element with an anti-parallel diode, a thyristor and a DIO diode.

15. The packaging structure according to claim 1, characterized in that: The bridge arm switch includes at least one of a SiC device and a GaN device.

16. The packaging structure according to claim 1, characterized in that: The bridge arm switch is a vertical device, and power electrodes with different electrical properties are respectively arranged on the upper surface and the lower surface of the vertical device.

17. The packaging structure according to claim 1, characterized in that: It also includes an active temperature signal element, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad; The active temperature signal element includes a temperature measurement unit, a signal processing unit, an output enable unit and an output switch device; one end of the temperature measurement unit is set to be grounded; the temperature measurement unit, the signal processing unit, the output switch device and the temperature signal pad are connected in series in sequence; the output switch device has a first end, a second end and a control end, the first end is electrically connected to the output end of the signal processing unit, and the second end is electrically connected to the temperature signal pad; the output enable unit controls the control end by comparing the potentials of the first end and the second end.

18. The packaging structure according to claim 1, characterized in that: It also includes a temperature-sensitive Zener diode, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad; one end of the Zener diode is set to be grounded, and the other end is electrically connected to the temperature signal pad.

19. The packaging structure according to claim 1, characterized in that: A packaging filling groove is opened at the edge of the multilayer circuit board; the packaging filling body fills the packaging filling groove.

20. The packaging structure according to claim 19, characterized in that: The side surface of the packaging filling body is provided with a creepage bulge or a creepage groove.

21. The packaging structure according to claim 20, characterized in that: The side surface of the packaging filling body is provided with a creepage bulge or a creepage groove, the horizontal extension length of which is not less than 1 mm.

22. The packaging structure according to claim 19, characterized in that: The thickness of the exposed portion of the side surface of the multilayer circuit board does not exceed 1 mm.

23. The packaging structure according to claim 1, characterized in that: The bottom surface of the insulating heat-conducting plate is also provided with a thick heat-conducting metal layer, and the packaging filling body covers the side surfaces of the thick heat-conducting metal layer.

24. The packaging structure according to claim 1, characterized in that: It also includes a fixing column, both ends of which are fixedly connected to the insulating heat-conducting plate and the multi-layer circuit board respectively.

25. The packaging structure according to claim 24, characterized in that: The insulating heat-conducting plate is divided into four quadrant areas in the horizontal direction, and at least one fixing column is arranged between the insulating heat-conducting plate and the multi-layer circuit board corresponding to each quadrant area.

26. The packaging structure according to claim 24, characterized in that: The multilayer circuit board is electrically connected to the fixing column and the power element respectively by welding, the height of the fixing column is Hpole, the sum of the thickness of the power element and its front electrode is Hdie, and Hdie-Hpole≥20μm.

27. The packaging structure according to claim 26, characterized in that: The area of ​​the steel mesh opening corresponding to the solder arranged on the fixing column in the welding process is not less than 120% of the welding area of ​​the top end of the fixing column.

28. The packaging structure according to claim 24, characterized in that: The total welding area of ​​the top end of the fixing column is not less than 2% of the area of ​​the insulating heat-conducting plate.

29. The packaging structure according to claim 1, characterized in that: The multilayer circuit board includes at least four wiring layers; each of the wiring layers is provided with a DC-wiring area, a DC+ wiring area and a SW wiring area arranged in sequence in one direction, or each of the wiring layers is provided with a DC+ wiring area, a DC- wiring area and a SW wiring area arranged in sequence in one direction; the four wiring layers include a first wiring layer and a second wiring layer, the first wiring layer and the second wiring layer are adjacent, the DC+ wiring area arranged in the first wiring layer is a large-area DC+ wiring area, the DC- wiring area arranged in the second wiring layer is a large-area DC- wiring area, and at least 10% of the projections of the large-area DC+ wiring area and the large-area DC- wiring area overlap with each other.

30. The packaging structure according to claim 29, characterized in that: It also includes a plurality of electrical connection columns, both ends of which are electrically connected to the insulating heat conductive plate and the multilayer circuit board respectively; the packaging filling body covers the electrical connection columns; the power element includes at least one vertical power chip; and the electrical connection columns are arranged in parallel between the power elements.

31. The packaging structure according to claim 30, characterized in that: The electrical connection column includes a SW end electrical connection column, and the SW end electrical connection column is electrically connected to the SW wiring area. The position corresponding to the SW end electrical connection column in the multi-layer circuit board is an avoidance area, and at least one of the DC+ wiring areas is arranged to bypass the avoidance area, or at least one of the DC- wiring areas is arranged to bypass the avoidance area.

32. The packaging structure according to claim 31, characterized in that: When at least one of the DC+ wiring areas is set up to bypass the avoidance area, the DC+ wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pads corresponding to the DC+ wiring area are long strips spanning the avoidance area; or, when at least one of the DC- wiring areas is set up to bypass the avoidance area, the DC- wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pads corresponding to the DC- wiring area are long strips spanning the avoidance area.

33. The packaging structure according to claim 29, characterized in that: It also includes at least one temperature sampling element, which is arranged between the upper bridge arm switch and the lower bridge arm switch in the direction of the connection line between the upper bridge arm switch and the lower bridge arm switch, and the temperature sampling element is arranged on one side of the multilayer circuit board in a direction perpendicular to the connection line between the upper bridge arm switch and the lower bridge arm switch.

34. The packaging structure according to claim 1, characterized in that: The power element includes at least one third-generation power semiconductor element or a low-voltage silicon power semiconductor element, or the Rsp of the power element does not exceed 2mOhm / cm 2 , the operating frequency of the board bridge power module is at least 100kHz.

35. The packaging structure according to claim 1, characterized in that: The power element includes at least two planar power semiconductor elements, and the aspect ratio of the planar power semiconductor elements is at least 1.

5.

36. The packaging structure according to claim 35, characterized in that: The at least two planar power semiconductor devices are arranged in parallel with their long sides and are interconnected by points to form at least one bridge arm. The multilayer circuit board includes a SW wiring area, a DC+ wiring area and a DC- wiring area, and the SW wiring area is arranged between the DC+ wiring area and the DC- wiring area.

37. The packaging structure according to claim 29 or 36, characterized in that: At least one of the DC-wiring area, the DC+wiring area, and the SW wiring area is provided with an exhaust hole, and a diameter of the exhaust hole is greater than 0.1 mm.

38. The packaging structure according to claim 36, characterized in that: It also includes at least two bridge arm decoupling capacitors, which are arranged at positions avoiding the insulating heat-conducting plate, and the bridge arm decoupling capacitors are arranged in a straight line.

39. The packaging structure according to claim 35, characterized in that: The power element includes at least four planar power semiconductor elements, which are arranged in 2 rows and 2 columns; the packaging structure also includes a temperature sampling unit, which is arranged in the middle of the at least four planar power semiconductor elements.

40. The packaging structure according to claim 1, characterized in that: It also includes a high-voltage isolation drive component, which is arranged on a multi-layer circuit board. The high-voltage isolation drive component is arranged on one side of the insulating heat-conducting plate and avoids the insulating heat-conducting plate.

41. The packaging structure according to claim 40, characterized in that: It also includes a temperature averaging plate, which is arranged on the heat dissipation surface and is connected to the insulating heat conducting plate with low thermal resistance.

42. The packaging structure according to claim 41, characterized in that: The packaging filling body covers the edges of the temperature equalizing plate and the thickness of the covering is at least 0.4 mm.

43. The packaging structure according to claim 42, characterized in that: It also includes a fixing column, both ends of which are fixedly connected to the temperature averaging plate and the multi-layer circuit board respectively.

44. The packaging structure according to claim 41, characterized in that: The temperature homogenizing plate is arranged outside the packaging filling body.

45. The packaging structure according to claim 40, characterized in that: An isolation groove is provided on the pad surface of the multilayer circuit board, the width and depth of the isolation groove are not less than 1 mm, and the isolation groove is used to increase the creepage distance between the high-voltage side and the low-voltage side.

46. ​​The packaging structure according to claim 45, characterized in that: The isolation grooves are arranged in a plurality.

47. The packaging structure according to claim 40, characterized in that: The high-voltage isolation driving component includes at least two driving chips; the driving chips are electrically connected through bonding wires, or the driving chips are planar driving chips and the driving chips are electrically connected through a multi-layer circuit board.

48. The packaging structure according to claim 1, characterized in that: It also includes an electrical connection column and a current sampling winding, wherein the current sampling winding is provided with at least one turn around the electrical connection column, the current sampling winding is used to sample the high-frequency current passing through the electrical connection column, and the current sampling winding is electrically connected to a current sampling circuit.

49. The packaging structure according to claim 48, characterized in that: The current sampling winding is arranged in a multi-layer circuit board, or is preformed with the electrical connection column to form an assembly.

50. The packaging structure according to claim 48, characterized in that: The current sampling circuit is provided with a correction function.

51. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: include: Welding a plurality of the packaging structures onto the same PCB substrate; A fixed housing and a common heat sink are provided, wherein the fixed housing is used to fix the common heat sink, and the fixed housing includes a cover plate located at the back side of the PCB substrate; A pressure ejector pin is arranged between the cover plate and the PCB substrate, and the position of the pressure ejector pin corresponds to the packaging structure; The common heat sink is pressed onto a plurality of packaging structures through the fixed shell, and during pressing, the PCB substrate is deformed by the pressure ejector pins so as to absorb the tolerance of each packaging structure in the thickness direction.

52. An application of the packaging structure of the half-bridge power module according to any one of claims 1 to 50, characterized in that: include: Welding a plurality of the packaging structures onto the same PCB substrate; A fixed shell and liquid-cooled radiators corresponding to the number of the packaging structures are provided. The fixed shell is used to press and fix the liquid-cooled radiators and the corresponding packaging structures. The fixed shell includes a heat dissipation liquid pipeline, an interface hose and a pressure elastic member; the interface hose is used to connect the liquid path between the heat dissipation liquid pipeline and the liquid-cooled radiators, so that the heat dissipation liquid pipeline and each liquid-cooled radiator form a connected integral liquid path. The liquid-cooled radiator is pressed and fixed on multiple packaging structures through the fixed shell. During pressing, the fixed shell applies pressure in the pressing and fixing direction to the liquid-cooled radiator through the pressure elastic member. The pressure elastic member and the interface hose absorb the tolerance of each packaging structure in the thickness direction through deformation.

53. An application of the packaging structure of the half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to an on-board OBC power converter, which includes a substrate and at least two of the half-bridge power modules. At least one power pin between the two half-bridge modules is electrically short-circuited through a system-side multilayer circuit board. The substrate includes a first component area, a second component area, and a third component area, which are arranged in sequence. The first component area is provided with a capacitor and a controller, the second component area is provided with the half-bridge power module, the heat dissipation surface of the half-bridge power module is provided with a heat sink, the third component area is provided with a transformer and an inductor, the winding of the inductor is integrated in the substrate, or the winding of the inductor is independently heat-dissipated and insulated from the iron core through cavity encapsulation of insulating thermal conductive glue, and the driving component corresponding to the bridge arm switch is arranged on the other side of the substrate corresponding to the half-bridge power module.

54. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a DCDC isolation converter, which includes a substrate, a transformer core and at least one half-bridge power module. The half-bridge power module is an input side module and / or an output side module. The transformer core is buckled on the substrate, and the winding corresponding to the transformer core is integrated in the substrate. The input side module and the output side module are respectively arranged on both sides of the transformer core. The heat dissipation surfaces of at least a part of the half-bridge power modules share a heat sink, and an insulating heat conductive member is arranged between the transformer core and the heat sink.

55. The application of the packaging structure of the half-bridge power module according to claim 54, characterized in that: The DCDC isolation converter further includes a secondary insulation processing structure, and the secondary insulation processing structure is a secondary plastic packaging body or a glue filling structure.

56. An application of the packaging structure of the half-bridge power module according to any one of claims 1 to 50, characterized in that: Applying the half-bridge power module to a non-isolated power converter, wherein the non-isolated power converter comprises a substrate, an inductor element and at least one half-bridge power module; The half-bridge power module is arranged on a substrate; The inductor element is arranged in parallel with the assembly of the half-bridge power module and the substrate, or the inductor element is arranged in parallel with the half-bridge power module on the substrate; The half-bridge power module and the inductor element share a heat sink, and the inductor element and the heat sink are directly provided with insulating heat conducting members.

57. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a cardiac arrest awakening device, which includes a shell, a first PCBA component layer, a second PCBA component layer and a filling glue. The first PCBA component layer and the second PCBA component layer are stacked in the shell, and the filling glue is filled in the gap between the shell, the first PCBA component layer and the second PCBA component layer; the first PCBA component layer includes a power supply element and a power supply drive element, and the second PCBA component layer includes at least one half-bridge power module, and at least one half-bridge power module is used to generate a high-voltage pulse output, and the heat dissipation surface of the half-bridge power module is in contact with the shell.

58. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a large IPM module, including: The heat dissipation surfaces of the multiple packaging structures are fixedly connected to the heat sink; they are soldered to the first PCB substrate through SMD; module circuit elements are arranged on the other side of the first PCB substrate; the module circuit elements include at least one of a control unit, a driving unit and a decoupling capacitor.

59. The use according to claim 58, characterized in that The large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting a plurality of bidirectional switch bridge arms in parallel.

60. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a large IPM module, including: The heat dissipation surfaces of the plurality of packaging structures are fixedly connected to a heat sink; they are soldered to a first PCB substrate through SMD; a second PCB substrate is provided, and module circuit elements are arranged on the second PCB substrate; the module circuit elements include at least one of a control conductor, a driving unit and a decoupling capacitor; the second PCB substrate and the first PCB substrate are electrically connected through elastic pins.

61. The use according to claim 60, characterized in that The large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting a plurality of bidirectional switch bridge arms in parallel.

62. The application of the packaging structure of the half-bridge power module according to claim 60, characterized in that: Also includes: Decoupling capacitors are arranged between and outside the packaging structures, and the decoupling capacitors are arranged on the heat sink through a thermal pad and are electrically connected to the first PCB substrate; A Vbus capacitor is arranged on the first PCB substrate; the Vbus capacitor is arranged adjacent to the assembly of the decoupling capacitor, the packaging structure and the heat sink.

63. The application of the packaging structure of the half-bridge power module according to claim 60, characterized in that: Also includes: A decoupling capacitor and an elastic pin are arranged on a surface of the first PCB substrate facing the second PCB substrate; A cover plate is installed on the first PCB substrate, the cover plate covers the decoupling capacitor, and the upper ends of the elastic pins extend out of the cover plate.

64. Application of the packaging structure of the half-bridge power module according to claim 62 or 63, characterized in that: Also includes: A suspended pad is provided on the surface of the first PCB substrate facing the second PCB substrate, the suspended pad is adjacent to a circuit node pad corresponding to a circuit node corresponding to one pin of a decoupling capacitor, the decoupling capacitor and the suspended pad are electrically connected, and an open circuit is maintained between the suspended pad and the corresponding circuit node pad; The leakage current of the packaging structure is tested, and after the test is qualified, the suspended pad is electrically connected to the corresponding circuit node pad.

65. An application of the packaging structure of the half-bridge power module according to any one of claims 3 to 5, characterized in that: The half-bridge power module is applied to an ANPC circuit, wherein the ANPC circuit includes a plurality of ANPC sub-units arranged in parallel, wherein the ANPC sub-units include a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, wherein the arm switches of the first half-bridge power module and the second half-bridge power module are both IGBT elements of anti-parallel diodes, and the first half-bridge power module and the second half-bridge power module are connected in series; The bridge arm switch of the third half-bridge power module is a MOS switch or an IGBT element of an anti-parallel diode, the half-bridge positive end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the second half-bridge power module.

66. An application of the packaging structure of the half-bridge power module according to any one of claims 3 to 5, characterized in that: The half-bridge power module is applied to a TNPC circuit, the TNPC circuit includes a plurality of TNPC sub-units arranged in parallel, the TNPC sub-units include a first half-bridge power module and a second half-bridge power module, the second half-bridge power module is a bidirectional switch module, the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the half-bridge positive end pad of the bidirectional switch module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the bidirectional switch module is grounded.

67. An application of the packaging structure of the half-bridge power module according to any one of claims 3 to 5, characterized in that: The half-bridge power module is applied to the Heric circuit. The Heric circuit includes a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, wherein the third half-bridge power module is a bidirectional switch module, and the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the first half-bridge power module and the second half-bridge power module are connected in parallel through the half-bridge positive end pad and the half-bridge negative end pad, and the bidirectional switch module is bridged between the half-bridge midpoint end pad corresponding to the first half-bridge power module and the half-bridge midpoint end pad of the second half-bridge power module.

68. A method for manufacturing a packaging structure of a half-bridge power module, characterized in that: The steps are as follows: S1: Assemble and fix the insulated heat conducting plate, multi-layer circuit board and bridge arm switch; S2: an overflow area is provided below the insulating heat conductive plate, and a space between the insulating heat conductive plate and the multilayer circuit board and the overflow area are simultaneously filled with a packaging filler, so that mold flow impacts of the upper and lower surfaces of the insulating heat conductive plate during packaging filling are offset, and a packaging filling body is formed in the space between the insulating heat conductive plate and the multilayer circuit board and the overflow area; S3: removing the packaging filling body in the overflow area by grinding; The bridge arm switch comprises an upper bridge arm switch and a lower bridge arm switch, each of the upper bridge arm switch and the lower bridge arm switch comprises at least one power element, the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface; The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit.

69. The method according to claim 68, characterized in that: The pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

70. The method according to claim 68, characterized in that: The thickness of the packaging filling body in the overflow area is not less than 0.3 mm.

71. The method according to claim 68, characterized in that: The heat dissipation surface is the back side of the insulating heat conductive plate, and the back side of the insulating heat conductive plate is provided with back side copper cladding. In step S1, the thickness of the back side copper cladding is not less than 150 μm.

72. The method according to claim 71, characterized in that: Step S3 also includes: thinning the back copper coating by grinding.

73. The method according to claim 71, characterized in that: The front side of the insulating heat conductive plate is provided with front copper cladding. In step S1, the thickness of the front copper cladding is smaller than the thickness of the back copper cladding. The difference between the thickness of the front copper cladding and the thickness of the back copper cladding is at least 50 μm.

74. The method according to claim 72, characterized in that: After step S3 , the thickness tolerance of the packaging structure does not exceed 100 μm.

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