A patch-type multi-pin TVS device and a manufacturing method thereof

Abstract

A surface-mount multi-pin TVS device and its manufacturing method are disclosed. The manufacturing method includes: arranging the components of the TVS device according to a preset arrangement, placing a pre-formed solder pad between every two components to form a pre-soldering module corresponding to the TVS device; subjecting the pre-soldering module to a first heat treatment to connect adjacent components together using the pre-formed solder pads to form a pre-packaged module corresponding to the TVS device; subjecting the pre-packaged module to a second heat treatment, coating the outer periphery of the pre-packaged module with encapsulation material having electrical insulation properties while the pre-packaged module is within a first preset temperature range; and subjecting the pre-packaged module to a third heat treatment to cure the encapsulation material, thereby forming an encapsulation insulating layer on the outside of the pre-packaged module to obtain the TVS device. This application can form TVS devices with more layers without being limited by the height of the PCB board, and can achieve higher voltage or current in the TVS device to meet the needs of high-current or high-voltage products.

Description

Technical Field

[0001] This invention relates to the field of TVS device technology, specifically to a surface-mount multi-pin TVS device and its manufacturing method. Background Technology

[0002] Existing surface mount TVS (TVS) diodes based on 8 / 20µs shortwave pulses for 3-10kA are limited by their packaging structure, typically using only 1-4 chips stacked together. Since the current-carrying capacity of TVS chips generally increases with lower voltage, and the 8 / 20µs shortwave current-carrying capacity of bidirectional P-type chips is far greater than that of N-type chips at the same voltage, the negative resistance characteristic of P-type bidirectional chips may affect practical applications once the voltage reaches a certain low level. Therefore, the maximum voltage of bidirectional chips is generally limited to 30V. Consequently, the voltage range of this type of product is limited to 90V-120V (with 3-4 chips stacked), and the maximum current-carrying capacity is only 10kA.

[0003] It is evident that the voltage of existing surface-mount TVS devices is not high enough, making them difficult to apply in fields requiring high voltage. Summary of the Invention

[0004] The main technical problem solved by this invention is that the existing surface mount TVS device manufacturing process limits the number of stacked layers, resulting in insufficient device voltage.

[0005] According to a first aspect, one embodiment provides a method for manufacturing a surface-mount multi-pin TVS device, comprising:

[0006] The components of the TVS device are arranged in a preset manner, and a pre-formed solder pad is placed between every two components to form a pre-welded module corresponding to the TVS device.

[0007] Each component includes two external electrodes, at least one internal electrode, multiple connecting pieces, and multiple TVS chips. The preset arrangement is as follows: multiple TVS chips are stacked along the thickness direction of the TVS chips, with an external electrode placed on the outer side of the outermost TVS chip, and connecting pieces placed between adjacent TVS chips; two connecting pieces are placed between at least one pair of adjacent TVS chips, and an internal electrode is placed between the two connecting pieces; the external electrode has a first pin extending along the width direction of the TVS chip, and the internal electrode has a second pin extending along the width direction of the TVS chip.

[0008] The pre-welded module undergoes a first heat treatment so that the pre-formed solder pads connect adjacent components together to form a pre-packaged module corresponding to the TVS device.

[0009] The pre-packaged module undergoes a second heat treatment. While the pre-packaged module is within a first preset temperature range, a packaging material is coated onto the outer periphery of the pre-packaged module. The packaging material has electrical insulation properties.

[0010] The pre-packaged module undergoes a third heat treatment to cure the packaging material, thereby forming a packaging insulating layer outside the pre-packaged module, resulting in a TVS device. The first pin of the external electrode and the second pin of the internal electrode are exposed outside the packaging insulating layer, and the first pin of the external electrode and the second pin of the internal electrode are located on the same side of the TVS device perpendicular to the thickness direction.

[0011] According to the second aspect, one embodiment provides a surface-mount multi-pin TVS device, including multiple components, multiple solder layers and a package insulating layer, wherein the multiple components include two external electrodes, at least one internal electrode, multiple connecting pieces and multiple TVS chips.

[0012] Multiple TVS chips are stacked along the thickness direction of the TVS chips. An external electrode is provided on the outer side of the outermost TVS chip, and a connecting piece is provided between adjacent TVS chips. At least one pair of adjacent TVS chips is provided with two connecting pieces, and an internal electrode is provided between the two connecting pieces. The external electrode has a first pin extending along the width direction of the TVS chip, and the internal electrode has a second pin extending along the width direction of the TVS chip.

[0013] The weld layer is used to connect two adjacent components, achieving a fixed connection between the two adjacent components;

[0014] An encapsulation insulating layer covers the exterior of multiple components. The first pin of the external electrode and the second pin of the internal electrode are exposed outside the encapsulation insulating layer, and the first pin of the external electrode and the second pin of the internal electrode are located on the same side of the TVS device perpendicular to the thickness direction.

[0015] According to a third aspect, one embodiment provides a surface-mount multi-pin TVS device manufactured using the manufacturing method described in the first aspect.

[0016] According to the surface mount multi-pin TVS device and its manufacturing method in the above embodiments, by arranging the components according to a preset arrangement, placing pre-formed solder pads between the components, and then using a first heat treatment, multiple TVS chips can be soldered together. This allows for a greater number of TVS chips to be stacked in the TVS device. After packaging, the first pin of the outer electrode and the second pin of the inner electrode are exposed outside the packaging insulating layer, and the first pin of the outer electrode and the second pin of the inner electrode are located on the same side of the TVS device perpendicular to the thickness direction. Therefore, the TVS device can be soldered in a vertical arrangement when it is bonded to the PCB, and the height of the device on the PCB remains unchanged, without being limited by the height of the PCB. This allows for a larger voltage or current of the TVS device, meeting the needs of high current or high voltage products. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an existing surface-mount TVS device;

[0018] Figure 2 A schematic diagram of the structure of a TVS device provided in one embodiment of this application (I);

[0019] Figure 3 This is a schematic diagram of a TVS device being soldered on a PCB board according to one embodiment of this application;

[0020] Figure 4 A schematic diagram (II) of the structure of a TVS device provided in one embodiment of this application;

[0021] Figure 5 A schematic diagram (III) of the structure of a TVS device provided in one embodiment of this application;

[0022] Figure 6 A schematic diagram (fourth) of the structure of a TVS device provided in one embodiment of this application;

[0023] Figure 7 This is a schematic diagram of the structure of the external electrode provided in one embodiment of this application;

[0024] Figure 8 A schematic diagram (V) of the structure of a TVS device provided in one embodiment of this application;

[0025] Figure 9 This is a schematic diagram of the internal electrode structure provided in one embodiment of this application;

[0026] Figure 10 A flowchart illustrating a manufacturing method provided in one embodiment of this application;

[0027] Figure 11 A schematic diagram (I) of a pre-welding module provided in one embodiment of this application;

[0028] Figure 12 A schematic diagram (II) of the structure of a pre-welded module provided in one embodiment of this application.

[0029] Reference numerals: 1-External electrode; 2-Internal electrode; 3-Connecting piece; 4-TVS chip; 5-Encapsulation insulating layer; 11-First pin; 12-Second pin. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0031] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0032] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0033] like Figure 1 As shown, in existing surface-mount TVS devices, multiple TVS chips are arranged along the thickness direction of the TVS chip ( Figure 1 The TVS chips are stacked vertically (top-bottom direction), with each pair of TVS chips soldered together via a copper plate. When the TVS chips are bonded to the PCB, their thickness direction is perpendicular to the PCB surface, resulting in a horizontal arrangement. To facilitate soldering, jumpers connect the pins to the copper plate, with two pins positioned on one side of the TVS device's thickness direction (corresponding to...). Figure 1 (The lower side of the TVS device).

[0034] like Figure 1As shown, before packaging a TVS device, multiple TVS chips need to be soldered to a copper plate, and the copper plate needs to be soldered to pins or jumpers. The overall process of manufacturing TVS chips is complex. The packaging layer needs to wrap the chip and jumpers, resulting in redundant packaging layers. This not only leads to a large amount of packaging material but also results in a large device size.

[0035] The applicant's research found that, Figure 1 The TVS chip shown is horizontally arranged and soldered during PCB bonding, with a height of ( Figure 1 Due to height limitations (in the top and bottom directions), only 1-4 layers of TVS chips can be placed on the PCB. Too many layers would result in unstable soldering on the PCB, and excessive height would affect the sealing. Therefore, due to these height limitations, TVS devices can generally only stack 3-4 TVS chips. Figure 1 As shown in the diagram (3 units), the voltage formed by connecting them in series is 90V-120V, and the maximum current carrying capacity is only 10KA. On the other hand, as... Figure 1 The TVS device shown has only two pins that can be electrically connected, only one operating mode, and lacks application in multi-voltage environments, making its applicability relatively limited.

[0036] The applicant's research found that by changing the structure of the TVS device and its orientation when it is bonded to the PCB, the TVS device can be soldered onto the PCB without being affected by height. At the same time, by introducing the internal electrode 2, the number of TVS chips 4 that need to be connected in series or in parallel can be selected, and the operating voltage and current of the TVS device can be changed, making it more adaptable to multi-voltage / multi-current application environments.

[0037] like Figure 2 As shown, this application embodiment provides a surface mount multi-pin TVS device (referred to as TVS device in this application embodiment), which may include multiple components (components may also be referred to as materials), multiple solder layers (not shown in the figure) and a packaging insulating layer 5. The multiple components may include two external electrodes 1, at least one internal electrode 2, multiple connecting pieces 3 and multiple TVS chips 4.

[0038] In this arrangement, multiple TVS chips 4 are stacked along the thickness direction of the TVS chips 4. An external electrode 1 is provided on the outer side of the outermost TVS chip 4, and a connecting piece 3 is provided between adjacent TVS chips 4. At least one pair of adjacent TVS chips 4 are provided with two connecting pieces 3, and an inner electrode 2 is provided between these two connecting pieces 3. The external electrode 1 has a first pin 11 extending along the width direction of the TVS chip 4 (perpendicular to the thickness direction of the TVS chip 4), and the inner electrode 2 has a second pin 12 extending along the width direction of the TVS chip 4.

[0039] A weld layer is used to connect two adjacent components, achieving a fixed connection between them. In some embodiments, the weld layer may take the form of a preformed solder sheet, which is melted and welded to the two adjacent components by heating. For example, the material of the weld layer may be a tin-lead alloy or a tin-lead-silver alloy.

[0040] An encapsulation insulating layer 5 covers the exterior of multiple components. The first pin 11 of the outer electrode 1 and the second pin 12 of the inner electrode 2 are exposed outside the encapsulation insulating layer 5, and the first pin 11 of the outer electrode 1 and the second pin 12 of the inner electrode 2 are located on the same side of the TVS device perpendicular to the thickness direction. Figure 2 On the right side of the middle.

[0041] In some embodiments, such as Figure 2 As shown, the first pin 11 of the external electrode 1 can be an L-shaped structure, providing a soldering surface that fits against the PCB board when the TVS device is soldered onto it, thus improving the convenience of soldering.

[0042] like Figure 3 As shown, when the TVS device provided in this embodiment is soldered to a PCB board, during soldering, the thickness direction of the TVS device is parallel to the surface of the PCB board, the TVS chip 4 is perpendicular to the surface of the PCB board, and the first pin 11 of the external electrode 1 and the second pin 12 of the internal electrode 2 face the surface of the PCB board. At this time, as the number of layers of the TVS chip 4 increases, it will only affect the thickness direction of the TVS device (…). Figure 3 The TVS device undergoes a dimensional change in the left-right direction, and in the width direction ( Figure 3 The dimensions (vertical direction) remain unchanged, and the height of the TVS device on the PCB board does not change. This means it is not limited by the height of the PCB board during soldering, allowing for the stacking of more TVS chip layers and enabling higher operating voltages and currents.

[0043] like Figure 4 As shown, taking the case where the TVS device includes two TVS chips 4 and one internal electrode 2 as an example, the TVS device provided in this application embodiment can realize a variety of electrical functions through multiple pins.

[0044] For example, Function 1: The first electrode can be cut short to be flush with the surface of the epoxy resin layer and is not needed; the second and third electrodes are connected in series with the internal chips of the device to achieve a connection method that increases the voltage.

[0045] Function 2: The first electrode can extend higher than the outer surfaces of the second and third electrodes, and can be inserted into the PCB board for positioning, preventing the product from tipping over during soldering. At the same time, it can achieve the voltage of a single chip between the first electrode and the second electrode or between the first electrode and the third electrode.

[0046] Function 3: Short-circuit the second and third electrodes, and connect the two internal chips in parallel for the first electrode to double the product's current carrying capacity.

[0047] In other words, taking two TVS chips 4 as an example, the TVS device provided in this application embodiment can realize the use of a single TVS, the series use of two TVS chips 4, and the parallel use of two TVS chips 4. Through different connection relationships of multiple pins, various changes in operating voltage and operating current can be realized, making it more versatile.

[0048] In some embodiments, the TVS device provided in this application may include multiple internal electrodes 2. One internal electrode 2 may be disposed between every two TVS chips 4, or multiple electrodes may be disposed as needed. Figure 5 As shown, a TVS device may include four TVS chips 4, and by setting an internal electrode 2, it can achieve the following: Figure 4 The three functions shown are similar.

[0049] In some embodiments, such as Figure 6 As shown, a TVS device can include six TVS chips 4. By setting two internal electrodes 2, more electrical functions can be achieved. For example, two, four, or six TVS chips 4 can be connected in series; or, for example, two TVS chips 4 can be connected in series to form a pair of chips, and two pairs of chips can be connected in parallel, or three pairs of chips can be connected in parallel. Alternatively, an internal electrode 2 can be set between every two TVS chips 4, which allows for more electrical connections between multiple TVS chips 4 and enables more electrical functions.

[0050] In some embodiments, such as Figure 7 As shown, the external electrode 1 can be a copper electrode, such as pure copper or a copper-iron alloy. The external electrode 1 can be surface-plated with silver, with a silver plating thickness ≥2.5µm. For example, if the TVS chip 4 is a square P-type TVS chip, the shape of the external electrode 1 matches the dimensions of the TVS chip 4, and it has a first pin 11 extending outward from the side. In some embodiments, such as... Figure 8 As shown, the two first pins 11 of the two external electrodes 1 of the TVS device are symmetrically arranged about the center of the device and are respectively located at... Figure 8 With this arrangement on both sides of the PCB, the TVS devices are more stable during soldering.

[0051] In some embodiments, such as Figure 9As shown, the inner electrode 2 can be a copper electrode, such as pure copper or a copper-iron alloy. The inner electrode 2 can be silver-plated, with a silver plating thickness ≥2.5µm. For example, if the TVS chip 4 is a square P-type TVS chip, the shape of the inner electrode 2 matches the shape of the TVS chip 4 and has a second pin 12 extending outward from the center. In some embodiments, the shape of the inner electrode 2 can be the same as that of the outer electrode 1.

[0052] In some embodiments, the connector 3 can be made of copper electrodes, such as bare copper, pure copper, or copper-iron alloy, and the external electrode 1 can be surface-plated with silver, with a silver plating thickness ≥2.5µm. The external dimensions of the connector can be slightly smaller than the TVS chip 4, and the two are basically the same.

[0053] In some embodiments, the material of the preformed solder sheet (soldering layer) can be a sheet of tin-lead alloy and tin-lead-silver alloy, such as 95%Pb5%Sn or 92.5%Pb5%Sn2.5%Ag alloy, and the thickness can be 0.05mm.

[0054] The above describes the surface-mount multi-pin TVS device provided in this application. The following describes its manufacturing method.

[0055] like Figure 10 As shown in the figure, this application provides a method for manufacturing a surface-mount multi-pin TVS device, which may include:

[0056] Step 1: Arrange the components of the TVS device according to the preset arrangement, and place a pre-formed solder pad between every two components to form the pre-welded module corresponding to the TVS device.

[0057] like Figure 11 As shown, each component may include two external electrodes 1, at least one internal electrode 2, multiple connecting pieces 3, and multiple TVS chips 4; the preset arrangement is as follows: multiple TVS chips 4 are stacked along the thickness direction of TVS chips 4, with an external electrode 1 placed on the outer side of the outermost TVS chip 4, and connecting pieces 3 placed between adjacent TVS chips 4; two connecting pieces 3 are placed between at least one pair of adjacent TVS chips 4, and an internal electrode 2 is placed between the two connecting pieces 3; the external electrode 1 has a first pin 11 extending along the width direction of TVS chip 4, and the internal electrode 2 has a second pin 12 extending along the width direction of TVS chip 4.

[0058] For example, such as Figure 12 As shown, the first pin 11 of the external electrode 1 can be pre-bent into an L-shaped structure of 90°. The first pins 11 of the two external electrodes 1 are distributed on the left and right sides.

[0059] In some embodiments, step 1, arranging the components of the TVS device according to a preset arrangement, may include:

[0060] The components of the TVS device are arranged along the thickness direction of the TVS chip 4 according to a preset arrangement. During arrangement, the movement of the components is restricted in a direction perpendicular to the thickness direction. For example, clamps are used for clamping and positioning. After arrangement, the components, along with the clamps, are placed in an oven for the first heat treatment.

[0061] Step 2: Perform a first heat treatment on the pre-welded module so that the pre-formed solder pads connect adjacent components together to form a pre-packaged module corresponding to the TVS device.

[0062] In some embodiments, the preformed solder sheet can be a tin-lead alloy or a tin-lead-silver alloy, and the heating temperature of the first heat treatment corresponds to 350±10℃. For example, heating in a vacuum furnace for 5-10 minutes melts the preformed solder sheet, which then cools to form a welding layer and welds two adjacent components together.

[0063] Step 3: Perform a second heat treatment on the pre-packaged module. While the pre-packaged module is within a first preset temperature range, coat the outer periphery of the pre-packaged module with encapsulation material that has electrical insulation properties. The first preset temperature range corresponds to the temperature of the second heat treatment.

[0064] In some embodiments, coating the outer periphery of the pre-packaged module with encapsulation material may include:

[0065] Step 301: Protect the first pin 11 of the outer electrode 1 and the second pin 12 of the inner electrode 2 so that the first pin 11 of the outer electrode 1 and the second pin 12 of the inner electrode 2 are not exposed.

[0066] Step 302: Coating treatment. The pre-packaged module undergoes a second heat treatment. Encapsulation material is coated on the outer periphery of the pre-packaged module, followed by shaking treatment to remove excess encapsulation material.

[0067] Step 303: Perform pre-curing treatment on the pre-encapsulated module after coating.

[0068] Step 304: Repeat the coating and pre-curing processes of the encapsulation material multiple times to ensure that the thickness of the encapsulation insulation layer 5 meets the preset thickness requirements.

[0069] For example, the encapsulation material can be an insulating material such as epoxy resin powder; when the epoxy resin powder is exposed to high temperatures, the polymer monomers inside can adhere to the surface of the copper material through a cross-linking reaction. The heating temperature for the second heat treatment is 150±10℃. For example, after clamping the inner electrode 2 or the outer electrode 1 with a fixture and baking it in an oven at 150℃ for 5 minutes, the inner electrode 2 or outer electrode 1 is dipped in epoxy resin powder for 3-10 seconds. Then, the pre-encapsulated module is lifted out of the epoxy resin powder surface and vibrated for 5-15 seconds to shake off the excess epoxy resin powder. Then, it is baked in an oven at 150℃ for 2-4 minutes, and then the epoxy resin powder is dipped twice more as described above.

[0070] Step 4: Perform a third heat treatment on the pre-packaged module to cure the packaging material so that the packaging material forms a packaging insulating layer 5 outside the pre-packaged module, thereby obtaining a TVS device. The first pin 11 of the external electrode 1 and the second pin 12 of the internal electrode 2 are exposed outside the packaging insulating layer 5, and the first pin 11 of the external electrode 1 and the second pin 12 of the internal electrode 2 are located on the same side of the TVS device perpendicular to the thickness direction.

[0071] For example, when the encapsulation material is epoxy resin powder, the heating temperature for the third heat treatment can be 150±10℃, such as curing by baking in an oven at 150℃ for 30 minutes.

[0072] In some embodiments, after obtaining the TVS device, the manufacturing method may further include:

[0073] Step 5: Determine which inner electrode 2 needs to be retained, and shorten the second pin 12 of the inner electrode 2 that needs to be retained so that the second pin 12 of the inner electrode 2 that needs to be retained is 0.2mm-0.5mm higher than the surface of the first pin 11 of the outer electrode 1; cut off the second pin 12 of the inner electrode 2 that does not need to be retained so that the second pin 12 of the inner electrode 2 that does not need to be retained is flush with the encapsulation insulating layer 5.

[0074] For example, such as Figure 6 As shown, assuming Figure 6 In the TVS device, in step 1, an internal electrode 2 is provided between every two TVS chips 4. In practical applications, it can be cut off, leaving only the two internal electrodes 2 shown in the figure.

[0075] In some embodiments, after obtaining the TVS device, the following may also be included:

[0076] Step 6: Solder the TVS device to the PCB board. During soldering, the thickness direction of the TVS device is parallel to the surface of the PCB board, the TVS chip 4 is perpendicular to the surface of the PCB board, and the first pin 11 of the external electrode 1 and the second pin 12 of the internal electrode 2 face the surface of the PCB board.

[0077] The TVS device described in the above embodiments can be manufactured using the manufacturing method described in the above embodiments, such as... Figures 2 to 6 As shown, multi-layered chip products can be designed according to the above manufacturing method as needed, and the number of chip layers can range from 2 to 28 layers or even more.

[0078] In summary, taking a P-type TVS chip as an example, the maximum voltage of a single chip is 30V. However, using the surface-mount multi-pin TVS device and its manufacturing method provided in this application, a current carrying capacity of 10-20kA or higher and a maximum voltage of 840V (corresponding to 28 layers) can be achieved, meeting the needs of products requiring high current carrying capacity or high voltage. Based on actual needs, by setting multiple internal electrodes 2 and adjusting the electrical connection relationships of multiple pins, devices with various electrical functions can be obtained to meet the needs of various scenarios.

[0079] This application can overcome the limitation of existing horizontally arranged devices by the soldering height of the PCB board, and can also realize devices with high voltage and high current. The electrical function can be adjusted as needed by the number of internal electrodes 2 and the electrical connection relationship of multiple pins (first pin 11 and second pin 12).

[0080] This document describes various exemplary embodiments with reference to them. However, those skilled in the art will recognize that changes and modifications can be made to the exemplary embodiments without departing from the scope of this document. For example, various operational steps and components for performing operational steps can be implemented in different ways depending on the specific application or considering any number of cost functions associated with the operation of the system (e.g., one or more steps can be deleted, modified, or combined with other steps).

[0081] While the principles herein have been illustrated in various embodiments, numerous modifications to the structure, arrangement, proportions, elements, materials, and components, particularly suited to specific environmental and operational requirements, may be used without departing from the principles and scope of this disclosure. These modifications and other alterations or alterations will be included within the scope of this document.

[0082] The foregoing specific descriptions have been described with reference to various embodiments. However, those skilled in the art will recognize that various modifications and changes can be made without departing from the scope of this disclosure. Therefore, considerations for this disclosure are to be illustrative rather than restrictive, and all such modifications are to be included within its scope. Similarly, advantages, other advantages, and solutions to problems with respect to various embodiments have been described above. However, benefits, advantages, solutions to problems, and any elements that produce these, or make them more explicit, should not be construed as critical, essential, or necessary. The term “comprising” and any other variations thereof as used herein are non-exclusive inclusion, meaning that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed or not part of the process, method, system, article, or apparatus. Furthermore, the term “coupled” and any other variations thereof as used herein refer to physical connections, electrical connections, magnetic connections, optical connections, communication connections, functional connections, and / or any other connections.

[0083] Those skilled in the art will recognize that many changes can be made to the details of the above embodiments without departing from the basic principles of the invention. Therefore, the scope of the invention should be determined only by the claims.

Claims

1. A method for manufacturing a surface-mount multi-pin TVS device, characterized in that, include: The components of the TVS device are arranged in a preset manner, and a pre-formed solder pad is placed between every two components to form a pre-welded module corresponding to the TVS device. The components include two external electrodes, at least one internal electrode, multiple connecting pieces, and multiple TVS chips. The preset arrangement is as follows: multiple TVS chips are stacked along the thickness direction of the TVS chips, with an external electrode placed on the outermost TVS chip and connecting pieces placed between adjacent TVS chips; at least one pair of adjacent TVS chips are connected by two connecting pieces, and an internal electrode is placed between the two connecting pieces; the external electrode has a first pin extending along the width direction of the TVS chip, and the internal electrode has a second pin extending along the width direction of the TVS chip. The pre-welded module is subjected to a first heat treatment so that the pre-formed solder pads connect adjacent components together to form a pre-packaged module corresponding to the TVS device. The pre-packaged module is subjected to a second heat treatment. When the pre-packaged module is in a first preset temperature range, a packaging material is coated on the outer periphery of the pre-packaged module. The packaging material has electrical insulation properties. The pre-packaged module is subjected to a third heat treatment to cure the packaging material so that the packaging material forms a packaging insulating layer outside the pre-packaged module, thereby obtaining the TVS device. The first pin of the external electrode and the second pin of the internal electrode are exposed outside the packaging insulating layer, and the first pin of the external electrode and the second pin of the internal electrode are located on the same side of the TVS device perpendicular to the thickness direction.

2. The manufacturing method as described in claim 1, characterized in that, After obtaining the TVS device, the process further includes: The TVS device is soldered to the PCB board. During soldering, the thickness direction of the TVS device is parallel to the surface of the PCB board, the TVS chip is perpendicular to the surface of the PCB board, and the first pin of the external electrode and the second pin of the internal electrode face the surface of the PCB board.

3. The manufacturing method as described in claim 1, characterized in that, The components of the TVS device are arranged according to a preset arrangement, including: The components of the TVS device are arranged in a preset manner along the thickness direction of the TVS chip, and during the arrangement, the components are restricted from moving in a direction perpendicular to the thickness direction.

4. The manufacturing method as described in claim 1, characterized in that, After obtaining the TVS device, the manufacturing method further includes: The inner electrodes that need to be retained are determined, and the second pins of the inner electrodes that need to be retained are shortened so that the surface of the second pins of the inner electrodes that need to be retained is 0.2mm-0.5mm higher than that of the first pins of the outer electrodes. The second pin of the internal electrode that does not need to be retained is cut off so that the second pin of the internal electrode that does not need to be retained is flush with the encapsulation insulating layer.

5. The manufacturing method as described in claim 1, characterized in that, The preformed solder sheet is a tin-lead alloy or a tin-lead-silver alloy, and the heating temperature of the first heat treatment is 350±10℃.

6. The manufacturing method as described in claim 1, characterized in that, The encapsulation material is epoxy resin powder; the heating temperature of the second heat treatment is 150±10℃; the heating temperature of the third heat treatment is 150±10℃.

7. The manufacturing method as described in claim 1, characterized in that, Applying encapsulation material to the outer periphery of the pre-encapsulated module includes: The first pin of the external electrode and the second pin of the internal electrode are protected so that the first pin of the external electrode and the second pin of the internal electrode are not exposed. The pre-packaged module undergoes a second heat treatment, during which packaging material is coated onto the outer periphery of the pre-packaged module, and a shaking process is performed to remove excess packaging material. The pre-encapsulated module that has been coated is subjected to a pre-curing process; The coating and pre-curing process of the encapsulation material is repeated multiple times to ensure that the thickness of the encapsulation insulating layer meets the preset thickness requirement.

8. A surface-mount multi-pin TVS device, characterized in that, The device is manufactured using the manufacturing method of any one of claims 1-7, and includes multiple components, multiple solder layers, and an encapsulation insulating layer. The multiple components include two external electrodes, at least one internal electrode, multiple connecting pieces, and multiple TVS chips. Multiple TVS chips are stacked along the thickness direction of the TVS chips. An external electrode is provided on the outer side of the outermost TVS chip, and a connecting piece is provided between adjacent TVS chips. At least one pair of adjacent TVS chips is provided with two connecting pieces, and an internal electrode is provided between the two connecting pieces. The external electrode has a first pin extending along the width direction of the TVS chip, and the internal electrode has a second pin extending along the width direction of the TVS chip. The welding layer is used to connect two adjacent components to achieve a fixed connection between the two adjacent components; The encapsulation insulating layer covers the exterior of the plurality of components, the first pin of the outer electrode and the second pin of the inner electrode are exposed outside the encapsulation insulating layer, and the first pin of the outer electrode and the second pin of the inner electrode are located on the same side of the TVS device perpendicular to the thickness direction.

9. The device as claimed in claim 8, characterized in that, The first pin of the external electrode has an L-shaped structure; the material of the welding layer is a tin-lead alloy or a tin-lead-silver alloy.

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