Switching device

Abstract

The utility model provides a switching device. The switching device comprises a tube shell, an MOSFET tube core and a TVS tube core group, wherein the MOSFET tube core and the TVS tube core group are arranged in the tube shell; the tube shell comprises a tube seat, a plurality of leading-out ends and an accommodating groove; a first metalized region, a second metalized region and a third metalized region are arranged at the bottom of the accommodating groove at intervals and are respectively connected with the leading-out end; the MOSFET tube core is attached to the first metallization region, the drain electrode is electrically connected with the first metallization region, and the source electrode and the grid electrode are electrically connected with the second metallization region and the third metallization region through bonding wires respectively; and the TVS tube core group comprises two TVS tube cores of which the cathodes are connected, and the anodes of the two TVS tube cores are electrically connected with the second metallization region and the third metallization region through bonding wires respectively. The two TVS chips are integrated between the grid electrode and the source electrode of the MOSFET through the design of the tube socket and the metallization area in the tube socket, so that a good electrostatic protection effect on the grid electrode of the power MOSFET is achieved, and the purpose of improving the ESD resistance of the power MOSFET device is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of power semiconductor devices, and in particular to a switching device. Background Art

[0002] MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is an insulated gate field-effect transistor. It is widely used in the power electronics industry due to its high input impedance, low noise, low power consumption, and wide safe operating area.

[0003] MOSFET-based switching devices generally have weak anti-static (ESD) capabilities. The reason is the special structure of power MOSFET devices. That is, to ensure the function of low-voltage control, the gate of power MOSFET devices generally uses a thin gate oxide layer, which leads to the device's weak anti-static ability. During installation and use, it often fails due to electrostatic damage.

[0004] To enhance ESD protection, current MOSFET device reinforcement measures include integrating ESD protection structures into MOSFET chip designs, such as introducing a Zener diode into the polysilicon between the gate and source. However, this approach requires extensive simulation and testing during chip design and process development. This not only increases design and process complexity but also results in increased chip area, reduced yield, and high development costs. Furthermore, due to the limitations of the injection concentration and energy of ESD protection structures like Zener diodes, this reinforcement has limited effectiveness in improving device ESD protection, typically only reaching 2000V (HBM) and difficult to improve further.

[0005] Therefore, how to effectively reinforce the gate of the MOSFET device against ESD to ensure that the ESD resistance of the switching device meets the use requirements is an urgent problem to be solved. Utility Model Content

[0006] In order to solve or improve the above-mentioned problems existing in the prior art, an embodiment of the present application provides a switching device, including a tube shell, a MOSFET tube die and a TVS tube die group;

[0007] The tube shell includes a tube base, a plurality of lead terminals and a cover plate sealed with the tube base, and the tube base has a receiving groove;

[0008] The bottom of the receiving groove is provided with a first metallized area, a second metallized area and a third metallized area spaced apart from each other, which are electrically connected to the plurality of lead terminals in a one-to-one correspondence.

[0009] The MOSFET die is mounted on the first metallization region, the drain is electrically connected to the first metallization region, and the source and gate are electrically connected to the second metallization region and the third metallization region respectively via bonding wires;

[0010] The TVS die group includes two TVS dies with cathodes connected to each other, and anodes of the two TVS dies are electrically connected to the second metallization region and the third metallization region respectively through bonding wires.

[0011] In the aforementioned technical solution, through the design of the tube seat and the metallized area therein, two TVS (transient voltage suppressor diode) tube cores are integrated between the gate and source of the MOSFET, thereby providing good electrostatic protection for the gate of the MOSFET tube core and achieving the purpose of improving the ESD resistance of the MOSFET device.

[0012] Optionally, the drain is located on the back side of the MOSFET die, and the source and gate are located on the front side of the MOSFET die; the back side of the MOSFET die is attached to the first metallization area via a conductive medium;

[0013] Alternatively, the drain, source and gate are all located on the front side of the MOSFET die; the back side of the MOSFET die is mounted on the first metallization area, and the drain is electrically connected to the first metallization area via a bonding wire.

[0014] Optionally, the first metallized region is disposed at one end of the bottom of the receiving groove, and the second metallized region and the third metallized region are disposed in parallel at the other end of the bottom of the receiving groove.

[0015] Optionally, the TVS die group is mounted between the second metallization area and the third metallization area; and anodes of two TVS dies in the TVS die group are electrically connected to the adjacent second metallization area or the third metallization area, respectively.

[0016] To avoid crossing of the bonding wires connecting the TVS die and the MOSFET die, the mounting areas of the two TVS die are set in the area between the second and third metallization areas, so that the anodes of the two TVS die can be electrically connected to their respective adjacent second or third metallization areas through metal bonding wires, thereby being connected to the source and gate of the MOSFET die respectively; in addition, as mentioned above, the cathodes of the two TVS die are also electrically connected to each other.

[0017] Optionally, the cathode of the TVS tube core group is arranged on the back side of the TVS tube core, and the anode is arranged on the front side of the TVS tube core; the switching device also includes a fourth metallization area, which is arranged between the second metallization area and the third metallization area; the cathodes of the two TVS tube cores in the TVS tube core group are both mounted on the fourth metallization area through a conductive medium.

[0018] The fourth metallization area is spaced apart from the other metallization areas, and the back surfaces of the two TVS tube cores are connected to the fourth metallization area by metal soldering or conductive adhesive, so that the back electrodes (cathodes) of the two TVS tube cores are electrically connected, and the front electrodes (anodes) of the TVS tube cores can be connected to the second or third metallization area respectively through metal bonding wires.

[0019] Optionally, the bottom of the receiving groove includes a bottom surface and a step surface, the first metallized area is arranged on the bottom surface, and the second metallized area, the third metallized area and the TVS die assembly are arranged on the step surface; the height of the step surface is greater than the top height of the MOSFET die after installation;

[0020] Since the TVS die group is disposed on the step surface, in an optional technical solution, the fourth metallization region for mounting the TVS die group is also disposed on the step surface.

[0021] The aforementioned step surface is provided to avoid damage to the metal bonding wire caused by the metal bonding wire being too high (the metal bonding wire being bent to a large extent), thereby ensuring the reliability of product performance.

[0022] Optionally, two TVS dies in the TVS die group share a substrate and a back metal layer, so that cathodes of the two TVS dies are electrically connected.

[0023] Optionally, the TVS die assembly is mounted on the bottom of the receiving groove through an insulating medium or a conductive medium.

[0024] Optionally, the TVS die group includes two TVS dies that are adjacently formed on the same wafer and are not separated.

[0025] Optionally, the plurality of lead terminals include a first lead terminal, a second lead terminal, and a third lead terminal electrically connected to the first metallization region, the second metallization region, and the third metallization region, respectively;

[0026] The plurality of lead-out terminals are respectively arranged on the outer side surface of the tube base on the same side of the connected metallized area, and extend to the outer bottom surface of the tube base, or extend away from the tube base for a predetermined distance.

[0027] The lead-out terminals extending to the outer bottom surface of the tube holder in the aforementioned optional solution enable the product to form a package that is convenient for surface mounting.

[0028] Optionally, a top surface metallized area is provided on the top surface of the opening of the receiving groove; and the cover plate is sealedly connected to the tube seat via the top surface metallized area.

[0029] Optionally, a sealing connection between the top metallized area on the tube holder and the cover plate is achieved by welding with a gold-tin solder ring to achieve good sealing.

[0030] To sum up, the switching device provided in the embodiment of the present application optimizes the design of the packaging structure and rationally arranges the MOSFET die and the TVS die. During the MOSFET packaging process, a suitable TVS die is integrated between the gate and source of the MOSFET die to reinforce the gate of the MOSFET, thereby improving the ESD resistance of the MOSFET device. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0032] Figure 1 is a circuit schematic diagram of a switching device in an embodiment of the present application;

[0033] Figure 2 1 is a schematic top view (front view) of a tube socket of a switching device in an embodiment of the present application;

[0034] Figure 3 1 is a bottom view (back view) of a tube socket of a switch device in an embodiment of the present application;

[0035] Figure 4 is a schematic side view of a tube socket of a switching device in an embodiment of the present application;

[0036] Figure 5 1 is a schematic half-section diagram of a tube base of a switch device in an embodiment of the present application, which shows a stepped structure inside the tube base;

[0037] Figure 6 1 is a schematic top view (front view) of a tube socket of another form of a switching device in an embodiment of the present application;

[0038] Figure 7 Schematic diagram of the installation and connection of various components in the switch device in the embodiment of the present application;

[0039] Figure 8 This is another installation and connection diagram of various components in the switch device in the embodiment of the present application.

[0040] Note in the figure:

[0041] 100: MOSFET die, 200: TVS die set, 300: tube seat;

[0042] 210: first TVS die, 220: second TVS die;

[0043] 310: receiving slot;

[0044] 311: bottom surface, 312: step surface;

[0045] 321: first metallization region, 322: second metallization region, 323: third metallization region, 324: fourth metallization region;

[0046] 330: top surface metallization area;

[0047] 341: first lead-out terminal, 342: second lead-out terminal, 343: third lead-out terminal;

[0048] 350: Groove. DETAILED DESCRIPTION

[0049] In this specification, it will also be understood that when a component is referred to as being relative to other components, such as being "connected to" other components, the component may be directly connected to or directly coupled to the other components, or there may also be a third component in between; in addition, in the embodiments of the present application, "connection" may specifically be an electrical (gas) connection or a structural connection.

[0050] The present application will now be described more fully below with reference to the accompanying drawings. However, the present application may be implemented in many different ways and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided herein to make the present application more detailed and complete and to fully convey the scope of the present application to those skilled in the art. Throughout the present application, the same reference numerals represent the same objects.

[0051] In order to solve the problems existing in the aforementioned prior art, one solution is to add electrostatic protection devices to the circuit system, such as adding a TVS (Transient Voltage Suppressors) between the gate and source of the MOSFET device. Further research found that the aforementioned measures would increase the design and manufacturing redundancy of the circuit system, and could not avoid electrostatic damage introduced during the testing and installation of the MOSFET device.

[0052] In view of this, an embodiment of the present application provides an electrostatic protection type switching device. By optimizing the packaging structure of the device, that is, during the MOSFET device packaging process, a TVS die group is integrated between the gate and source of the MOSFET die (Die), which not only avoids increasing the design and manufacturing redundancy of the circuit system, but also avoids electrostatic damage introduced during testing and installation.

[0053] The circuit principle is as follows Figure 1As shown, the device includes a MOSFET die 100 and a TVS die group 200. The cathodes of the two TVS dies in the TVS die group 200 are connected, and the anodes are respectively connected to the source and gate of the MOSFET die 100. The gate, source, and drain of the MOSFET die 100 are respectively connected to the three external terminals of the switching device.

[0054] Based on the aforementioned circuit principles and circuit structures, the electrostatic protection switch device provided in the embodiments of the present application includes the following optimized packaging structure:

[0055] The tube shell includes a tube base 300 and a cover plate, wherein the tube base 300 is provided with a receiving groove 310 for cooperating with the cover plate to form a cavity;

[0056] The MOSFET die 100 and the TVS die group 200 are disposed in the receiving groove 310 , wherein the TVS die group 200 includes two TVS dies, which are respectively denoted as a first TVS die 210 and a second TVS die 220 .

[0057] The housing also includes multiple terminals, each of which includes conductors extending outside the housing. These terminals serve as terminals for the switching devices and correspond to the source, drain, and gate electrodes of the MOSFET die 100. Depending on the package type, the terminals may be pins extending from the housing 300 or metallized areas attached to the outer wall of the housing 300.

[0058] like Figure 2 As shown, a first metallized area 321, a second metallized area 322 and a third metallized area 323 are arranged at intervals at the bottom of the accommodating groove 310, that is, the first metallized area 321, the second metallized area 322 and the third metallized area 323 are insulated from each other, and the three metallized areas are electrically connected to multiple lead terminals one by one.

[0059] like Figure 2 、 Figure 7 or Figure 8 As shown, MOSFET die 100 is mounted on first metallization region 321, with its drain D electrically connected to first metallization region 321, source S electrically connected to second metallization region 322, and gate G electrically connected to third metallization region 323. TVS die assembly 200 includes a first TVS die 210 and a second TVS die 220 connected in cathode. The anodes of the two TVS dies are electrically connected to second metallization region 322 and third metallization region 323, respectively. Thus, TVS die assembly 200 is connected between source S and gate G of MOSFET die 100.

[0060] Depending on the electrode distribution of the MOSFET die 100, the connection method between the three metallization areas can vary. For example, if the drain D of the MOSFET die 100 is located on the back of the die, and the source S and gate G are located on the front of the die, in a typical embodiment, the back of the MOSFET die 100 is attached to the first metallization area 321 via a conductive medium, so that the drain D is electrically connected to the first metallization area 321; the source S is electrically connected to the second metallization area 322 via a bonding wire, and the gate G is electrically connected to the third metallization area 323 via a bonding wire.

[0061] For the case where the three electrodes of the MOSFET die 100 are all located on the same side of the die, that is, all located on the front side of the die, in a typical embodiment, the back side of the MOSFET die 100 is bonded to the first metallization area 321, and the source S, gate G, and drain D located on the front side of the MOSFET die 100 are electrically connected to the second metallization area 322, the third metallization area 323 and the first metallization area 321 respectively through metal bonding wires.

[0062] In the aforementioned embodiment, the first metallization region 321 serves as the mounting area for the MOSFET die 100. The MOSFET die 100 can be mounted on the first metallization region 321 by means of metal soldering or conductive adhesive bonding. In an embodiment where the drain D is located on the back side of the die and the source S and gate G are located on the front side of the die, the metal solder or conductive adhesive can also achieve electrical connection between the drain D on the back side of the MOSFET die 100 and the first metallization region 321.

[0063] In this embodiment, the first metallized region 321 is electrically connected to the corresponding lead-out terminals via wires disposed within the sidewall of the stem 300, thereby electrically connecting the drain of the MOSFET die 100 to an external circuit. Similarly, the second metallized region 322 and the third metallized region 323 are also electrically connected to the corresponding lead-out terminals via wires disposed within the sidewall of the stem 300, thereby electrically connecting the source and gate of the MOSFET die 100 to an external circuit, respectively. The specific electrical connection methods are known in the art and will not be further described here.

[0064] In the aforementioned embodiment, by packaging the manufactured MOSFET die 100 and TVS die group 200 in the same tube shell, the complexity and limitations of designing and manufacturing an integrated anti-ESD structure and the design redundancy of adding an ESD protection structure in the circuit system can be avoided. It is also possible to specifically select TVS chips of appropriate specifications for different power MOSFET devices to improve the anti-ESD capability of the switching device.

[0065] It should also be noted that the above-mentioned MOSFET includes but is not limited to LDMOS (Laterally Diffused Metal Oxide Semiconductor) and VDMOS (Vertical Doublediffused Metal Oxide Semiconductor).

[0066] In a typical embodiment, Figure 2 、 Figures 6 to 8 As shown, the first metallized region 321 is disposed at one end of the bottom of the receiving groove 310, such as the left side in the figure, and the second metallized region 322 and the third metallized region 323 are disposed side by side at the other end of the bottom of the receiving groove 310, such as the right side in the figure. Figure 7 As shown, after the MOSFET die 100 and the TVS die group 200 are installed, the bonding wires between the MOSFET die 100 and the second metallization region 322 and the third metallization region 323, as well as the bonding wires between the second metallization region 322 and the third metallization region 323 and the TVS die group 200, generally form a triangular arrangement to avoid crossing between the bonding wires.

[0067] Preferably, Figure 7 The second metallization region 322 and the third metallization region 323 are arranged vertically, and correspondingly, the source S and the gate G of the MOSFET die 100 are also arranged vertically, the source S is arranged on the top and connected to the second metallization region 322 also arranged on the top through a bonding wire, and the gate G is arranged on the bottom and connected to the third metallization region 323 also arranged on the bottom through a bonding wire.

[0068] In an alternative embodiment, if Figure 2 、 Figures 6 to 8 As shown, the first metallization region 321 occupies more than half of the bottom area of ​​the receiving groove 310 , which is significantly larger than the area occupied by the MOSFET die 100 , so as to facilitate adjustment of the installation position of the MOSFET die 100 .

[0069] Since the second metallization area 322 and the third metallization area 323 only need to be welded with bonding wires to establish electrical connections between the electrodes of the MOSFET die 100 and the electrodes of the TVS die group 200 without the need for die mounting, the area can be relatively small, making the overall structure of the switching device more compact.

[0070] As mentioned above, according to the different packaging forms of actual applications, the above-mentioned multiple lead-out terminals can adopt different structures. In the embodiment, in order to adapt to the SOT 23-03A metal ceramic surface mount package, such as Figure 3 and Figure 4 As shown, the lead-out terminals are arranged on the back of the tube base 300. Of course, in order to adapt to other packaging forms, such as SOT 23 packaging, the structure of the lead-out terminals in the embodiment may also be changed accordingly.

[0071] In a typical embodiment, Figure 4 As shown, the lead-out end is led out from the middle of the side of the tube base 300, and extends to the outer bottom surface of the tube base 300 in close contact with the side wall of the tube base 300, and extends a certain length toward the middle of the outer bottom surface, as shown in FIG. Figure 3 In addition, the lead-out terminal can also be led out from the middle of the side of the tube base 300 and extend a certain distance away from the tube base 300 to form a gull-wing pin. In practice, the specific type of the lead-out terminal can be selected according to the actual packaging requirements.

[0072] like Figure 3 As shown, specifically, the plurality of lead ends include a first lead end 341 , a second lead end 342 and a third lead end 343 which are electrically connected to the first metallization region 321 , the second metallization region 322 and the third metallization region 323 , respectively.

[0073] The first lead terminal 341 is electrically connected to the first metallization region 321 and is disposed on the same side of the first metallization region 321, corresponding to the drain D of the MOSFET die 100. Similarly, the second lead terminal 342 and the third lead terminal 343 are disposed on the same side of the second metallization region 322 and the third metallization region 323, respectively, and correspond to the source S and gate G of the MOSFET die, respectively.

[0074] In a preferred embodiment, the position where the lead-out end is set on the outer side surface of the tube base 300 has a groove 350 to mark the position of the lead-out end and play a positioning role to facilitate processing and use.

[0075] In a typical embodiment, Figure 2 、 Figures 6 to 8 As shown, a top metallized region 330 is provided on the top surface of the opening of the receiving groove 310; the cover plate is welded to the top metallized region 330. In one embodiment, the cover plate can be sealed to the top metallized region 330 by welding with a gold-tin solder ring to achieve a sealed connection between the cover plate and the tube base 300, thereby achieving good airtightness.

[0076] In a preferred embodiment, Figure 7 or Figure 8As shown, the TVS die group 200 is mounted between the second metallization region 322 and the third metallization region 323 ; the anodes in the TVS die group 200 are electrically connected to the adjacent second metallization region 322 or the third metallization region 323 .

[0077] In a typical embodiment, Figure 6 and Figure 8 As shown, a fourth metallization region 324 is further included. The fourth metallization region 324 is insulated from the other metallization regions and is disposed between the second metallization region 322 and the third metallization region 323 . The fourth metallization region 324 is used to interconnect the cathodes of the two TVS dies in the TVS die group 200 .

[0078] Specifically, the cathodes on the back of the two TVS dies in the TVS die group 200 are mounted on the fourth metallization area 324 through a conductive medium, thereby achieving mutual electrical connection of the cathodes, and the anodes on the front of the two TVS dies can be electrically connected to the adjacent second metallization area 322 or the third metallization area 323 through metal bonding wires.

[0079] Regarding the electrical connection method for the cathodes of the two TVS dies in TVS die assembly 200, in addition to the use of the fourth metallization region 324 for electrical connection in the aforementioned embodiment, in a preferred embodiment, the two TVS dies in TVS die assembly 200 share a substrate and back metal layer, thereby naturally electrically connecting the cathodes of the two TVS dies. TVS die assembly 200 can be mounted to the bottom of receiving groove 310 via an insulating medium. Optionally, TVS die assembly 200 includes two TVS dies formed adjacently on the same wafer without being separated. This allows the cathodes of the two TVS dies to be naturally connected.

[0080] The term "die" as used in this disclosure refers to the die obtained by slicing the wafer along the scribe lines (i.e., dicing) after wafer processing is completed. In the aforementioned preferred embodiment, two adjacent TVS dies on the wafer are diced as a group. The two dies are connected by the scribe lines without being separated. The resulting "die" is actually a TVS die group including two TVS dies, and the back metal layers and even the semiconductor substrate of the two TVS dies are still connected as a whole.

[0081] In other words, for the above-mentioned preferred embodiment, and the metal layer on the back of the wafer is used as the cathode of the TVS, then the cathodes of the two tube cores are naturally connected, and there is no need to use other means to electrically connect the cathodes of the two TVS tube cores. In addition to ensuring a reliable electrical connection between the back electrodes of the two TVS tube cores, the above-mentioned method can also minimize the installation area occupied by the two TVS tube cores. Moreover, since the two TVS tube cores come from the same wafer, the performance parameters should be consistent or extremely close, which can also improve the ESD resistance of the entire electrostatic protection type switch device to a certain extent. In addition, compared to two independent TVS tube cores that need to be bonded to the bottom of the receiving groove 310 respectively, the solution of the preferred embodiment is adopted, that is, the TVS tube core group 200 includes two TVS tube cores formed adjacently on the same wafer and not separated, which can save the number of bonding times, thereby shortening the processing time of the switch device to a certain extent and improving the processing efficiency.

[0082] The above embodiments are suitable for the situation where the cathodes and anodes of the two TVS tube cores are located on different surfaces of the tube core; for the situation where the cathodes and anodes of the two TVS tube cores in the TVS tube core group 200 are both on the same surface of the tube core, that is, both are located on the front surface of the tube core, the cathodes of the two TVS tube cores can be connected by metal bonding wires.

[0083] In the above embodiment, to ensure that the MOSFET can work normally and the electrostatic energy can be discharged before the gate is damaged by breakdown, a TVS die with a breakdown voltage higher than the operating voltage of the MOSFET and lower than the gate breakdown voltage of the MOSFET chip should be selected.

[0084] In the aforementioned embodiment, among the three electrodes of the MOSFET die 100, at least the gate G and the source S are electrically connected to the second metallization region 322 and the third metallization region 323 respectively through metal bonding wires. Due to the limited height of the accommodating groove 310 of the tube seat, the pads (PAD) corresponding to the gate and source of the MOSFET die 100 are close to the corresponding second / third metallization regions, and the diameter of the metal bonding wire is relatively thin (generally 40 microns and 70 microns). Therefore, during the bonding process, the metal bonding wire may be damaged due to the metal bonding wire being too high (i.e., the metal bonding wire is bent to a large extent).

[0085] In view of the above phenomenon, in a preferred embodiment, as Figure 5 As shown, the bottom of the receiving groove 310 includes a bottom surface 311 and a step surface 312. Obviously, the step surface 312 is higher than the bottom surface 311. The first metallization area 321 is set on the bottom surface 311, and the second and third metallization areas and the TVS tube core group 200 are all set on the step surface 312.

[0086] In the embodiment including the fourth metallization region 324 , since the TVS die assembly 200 is disposed on the step surface 312 , the fourth metallization region 324 on which the TVS die assembly 200 is mounted is also disposed on the step surface 312 .

[0087] In a typical embodiment, the step surface 312 is provided at the junction of the bottom surface 311 and the side wall of the receiving groove 310 .

[0088] The height of the step surface 312 is greater than the top height of the MOSFET die 100 after installation. For example, if the MOSFET die 100 is bonded to the first metallization area 321 by conductive adhesive, the height of the step surface 312 is greater than the thickness of the MOSFET die 100 plus the thickness of the conductive adhesive layer.

[0089] In the embodiment, the step should not be too high, and a certain space should be left between the highest point of the metal bonding wire arch and the cover plate after bonding to avoid contact and ensure product reliability.

[0090] To sum up, the switching device provided in the embodiment of the present application optimizes the design of the packaging structure, and rationally arranges the MOSFET die and TVS die. During the MOSFET device packaging process, a suitable TVS die is integrated between the gate and source of the die, thereby reinforcing the gate of the MOSFET to improve the ESD resistance of the MOSFET device. It has been verified that the product's ESD resistance can reach above 2000V (HBM).

[0091] The above descriptions are only some specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the embodiments of the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A switching device, characterized in that: It comprises a tube shell, a MOSFET tube core (100) and a TVS tube core group (200); The tube shell comprises a tube base (300), a plurality of lead terminals, and a cover plate sealedly connected to the tube base (300), wherein the tube base (300) has a receiving groove (310); The bottom of the receiving groove (310) is provided with a first metallized area (321), a second metallized area (322), and a third metallized area (323) spaced apart from each other, and electrically connected to the plurality of lead ends in a one-to-one correspondence. The MOSFET die (100) is mounted on the first metallization region (321), the drain is electrically connected to the first metallization region (321), and the source and gate are electrically connected to the second metallization region (322) and the third metallization region (323) respectively via bonding wires; The TVS tube core group (200) comprises two TVS tube cores connected to each other at cathodes, and anodes of the two TVS tube cores are electrically connected to the second metallization region (322) and the third metallization region (323) respectively through bonding wires.

2. The switching device according to claim 1, wherein: The drain is located on the back side of the MOSFET die (100), and the source and gate are located on the front side of the MOSFET die (100); the back side of the MOSFET die (100) is attached to the first metallization area (321) via a conductive medium; Alternatively, the drain, source, and gate are all located on the front side of the MOSFET die (100); the back side of the MOSFET die (100) is attached to the first metallization area (321), and the drain is electrically connected to the first metallization area (321) via a bonding wire.

3. The switching device according to claim 1, wherein: The first metallized region (321) is arranged at one end of the bottom of the receiving groove (310), and the second metallized region (322) and the third metallized region (323) are arranged in parallel at the other end of the bottom of the receiving groove (310).

4. The switching device according to claim 3, wherein: The TVS die group (200) is mounted between the second metallization area (322) and the third metallization area (323); The anodes of the two TVS tube cores are electrically connected to the adjacent second metallization region (322) or the third metallization region (323), respectively.

5. The switching device according to claim 4, characterized in that: The cathode of the TVS tube core group (200) is arranged on the back side of the TVS tube core, and the anode is arranged on the front side of the TVS tube core; The switching device further comprises a fourth metallization region (324) disposed between the second metallization region (322) and the third metallization region (323); the cathodes of the two TVS tube cores are both mounted on the fourth metallization region (324) via a conductive medium.

6. The switching device according to any one of claims 3 to 5, characterized in that: The bottom of the receiving groove (310) comprises a bottom surface (311) and a step surface (312); the first metallized region (321) is arranged on the bottom surface (311); the second metallized region (322), the third metallized region (323) and the TVS die group (200) are arranged on the step surface (312); The height of the step surface (312) is greater than the top height of the MOSFET die (100) after installation.

7. The switching device according to claim 1 or 4, characterized in that: The two TVS tube dies in the TVS tube die group (200) share a substrate and a back metal layer so that the cathodes of the two TVS tube dies are electrically connected.

8. The switching device according to claim 7, wherein: The TVS tube die group (200) comprises two TVS tube dies which are adjacently formed on the same wafer and are not separated.

9. The switching device according to claim 1 or 3, characterized in that: The plurality of lead ends include a first lead end (341), a second lead end (342) and a third lead end (343) which are electrically connected to the first metallization region (321), the second metallization region (322) and the third metallization region (323), respectively; The plurality of lead-out ends are respectively arranged on the outer side surface of the tube seat (300) on the same side as the connected metallized area, and extend to the outer bottom surface of the tube seat (300), or extend away from the tube seat (300) by a predetermined distance.

10. The switching device according to claim 1, wherein: A top surface metallized area (330) is provided on the top surface of the opening of the receiving groove (310), and the cover plate is sealedly connected to the tube seat (300) via the top surface metallized area (330).

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