Longitudinal electric connector based on printed circuit board and application thereof

Abstract

The invention discloses a longitudinal electric connecting piece based on a printed circuit board. The longitudinal electric connecting piece comprises a layered insulation structure and a metal connecting piece arranged in the layered insulation structure. At least one end of the metal connecting piece is provided with an easy-to-deform part exposed out of the layered insulation structure, and the easy-to-deform part is exposed out by etching the layered insulation structure on the printed circuit board. On the other hand, the invention discloses application of the longitudinal electric connecting piece based on the printed circuit board. The longitudinal electric connecting piece is applied to a power module. When the structure is assembled to a power module and the like, press fit and leveling of an assembly structure are facilitated, and the flatness of an assembly body can be effectively improved; in addition, the welding area can be effectively increased, a welding exhaust channel is provided, a welding spot crack propagation path is blocked and the like, the connection reliability can be effectively improved, and due to the existence of the easily-deformed part, the service reliability in severe environments such as high vibration and high temperature change range can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of high-frequency power supply, and in particular relates to a longitudinal electrical connector based on a printed circuit board and an application thereof. Background Art

[0002] With the increasing demand for various artificial intelligence and data processing, global computing power consumption has exploded. Moreover, due to the extremely high size restrictions of these computing units, higher and higher requirements are placed on the floor space, height, efficiency, heat dissipation, and reliability of energy processing units.

[0003] A typical two-stage power supply architecture, the front stage is 48V to 12V (5V), and the back stage is 12V (5V) to the processor's operating voltage, about ~1V. The front stage module usually contains a magnetic component, a transformer, because its voltage conversion is relatively high; the back stage usually uses a buck circuit, which contains a magnetic component, an inductor.

[0004] Since these energy processing units need to receive / output numerous signals, how to achieve high-density, high-reliability interconnection of the energy processing units' signals and avoid interference from adjacent magnetic components and voltage jump points on the signals to ensure the functional safety of the energy processing units. In addition, since the height of the connector needs to be consistent with the height of the remaining parts, the height difference caused by the respective processing tolerances poses a major challenge to the reliable formation of the welded joints. All of the above are issues that need to be urgently addressed. Summary of the invention

[0005] In view of this, one of the objects of the present invention is to provide a longitudinal electrical connector based on a printed circuit board, which is conducive to pressing and leveling the assembly structure when assembled to a power module and other structures, and can effectively improve the flatness of the assembly; it can also effectively increase the welding area, provide a welding exhaust channel, block the expansion path of solder joint cracks, etc., and can effectively increase the connection reliability.

[0006] To achieve the above-mentioned purpose, the present invention provides a longitudinal electrical connector based on a printed circuit board, wherein the longitudinal electrical connector includes a layered insulating structure and a metal connector arranged in the layered insulating structure; at least one end of the metal connector has an easily deformable portion exposed to the layered insulating structure, and the easily deformable portion is exposed by etching the layered insulating structure on the printed circuit board.

[0007] Preferably, the deformable portion is a layered metal connection structure before the layered insulating structure is etched.

[0008] Preferably, the easily deformable portion is a metal layer on the inner wall of the hole before the layered insulating structure is etched.

[0009] Preferably, the deformable portion is a combination of a layered metal connection structure and a metal layer on the inner wall of the hole before the layered insulating structure is etched.

[0010] Preferably, the length of the easily deformable portion is greater than twice its thickness.

[0011] Preferably, the layered metal connection structure corresponding to the deformable portion is a multi-layer stacked arrangement or a multi-layer staggered arrangement.

[0012] Preferably, the hole inner wall metal layer is a through hole inner wall metal layer or a segmented hole inner wall metal layer.

[0013] Preferably, the surface of the easily deformable portion is coated with an anti-oxidation coating.

[0014] Preferably, at least two easily deformable portions adjacent to each other in the thickness direction correspond to the same electrode.

[0015] On the other hand, the present invention provides an application of the above-mentioned longitudinal electrical connector, wherein the longitudinal electrical connector is used in a power module, wherein the power module comprises at least one of the longitudinal electrical connectors and at least one large-volume component, wherein the longitudinal electrical connector is arranged on at least one side of the large-volume component, wherein the longitudinal electrical connector and the large-volume component form an assembly, and wherein the upper end and / or the lower end of the longitudinal electrical connector is leveled so that the height difference between the end face of the easily deformable portion and the welding surface of the large-volume component is less than or equal to 50 μm.

[0016] Preferably, the power module further includes a top component and a bottom component, the top component includes a top plate and a power chip and a capacitor element arranged on the top plate, and the bottom component includes a bottom plate, and the top plate and the bottom plate are respectively welded to the top surface and the bottom surface of the assembly.

[0017] The beneficial effects of the present invention are:

[0018] (1) The longitudinal electrical connector of the present invention can reduce loop inductance through wiring design, and effectively prevent signal interference by setting a shielding layer, etc.; the present invention can also be cut into large pieces, suitable for batch manufacturing, and has small dimensional tolerance and high consistency; the present invention can fully utilize the advantages of flexible internal wiring design, reduce the volume of the connector, save space, increase the number of pin fan-outs, and improve the interconnection density;

[0019] (2) The present invention facilitates the pressing and leveling of the assembly structure through the easily deformable portion of the layered insulating structure, which can effectively improve the flatness of the assembly; it can also effectively increase the welding area, provide a welding exhaust channel, block the crack propagation path of the weld point, etc., which can effectively increase the connection reliability. The presence of the easily deformable portion can increase the reliability of service in harsh environments such as high vibration and high temperature variation range. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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.

[0021] Figure 1 It is a schematic structural diagram of the longitudinal electrical connector disclosed in the present invention;

[0022] Figures 2 to 7B It is a structural schematic diagram of the easily deformable portion disclosed in an embodiment of the present invention;

[0023] Fig. 8A and Figure 8B A schematic diagram of an electrode of a longitudinal electrical connector disclosed in an embodiment of the present invention;

[0024] FIG. 9A to FIG. 10 It is a structural schematic diagram of the application of the longitudinal electrical connector disclosed in the embodiment of the present invention. DETAILED DESCRIPTION

[0025] 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.

[0026] This embodiment discloses a longitudinal electrical connector based on a printed circuit board, such as Figure 1 As shown, the longitudinal electrical connector 1 includes a layered insulating structure 3 and a metal connector arranged in the layered insulating structure; at least one end of the metal connector has an easily deformable portion 2 exposed to the layered insulating structure, and the easily deformable portion 2 is exposed by etching the layered insulating structure on the printed circuit board.

[0027] Specifically: the printed circuit board has an upper end and a lower end, the upper end is provided with a first easily deformable portion, and the lower end is provided with a second easily deformable portion. The first easily deformable portion and the second easily deformable portion are connected by a metal connector of the printed circuit board. When the easily deformable portion is assembled to a structure such as a power module, the tolerance is absorbed by deformation, thereby ensuring the welding quality.

[0028] The method of making the deformable part is as follows:

[0029] Step 1: Make a mother board of the printed circuit board, cut it into strips, the cutting surface corresponds to the upper and lower end surfaces of the longitudinal electrical connector, and form a mother strip of the printed circuit board whose deformable part is not completely exposed (for this embodiment, the metal at the cross section will be exposed, and in some other embodiments, when the deformable part is the metal layer on the inner wall of the hole, it may not be exposed);

[0030] Step 2: Dry-etch the layered insulating structure at the upper and / or lower ends of the printed circuit board to expose the easily deformed portion, and the etching gas is a mixture of CF4 and O2;

[0031] Step 3: Surface treatment, including ENIG and other anti-oxidation treatment on the surface of the easily deformed part;

[0032] Step 4: Cut the mother strip of the printed circuit board by laser depaneling or other methods to form independent longitudinal electrical connectors.

[0033] In a preferred embodiment, if Figure 2 As shown, the easily deformable portion 2 is a surface layer or inner layer metal interconnection structure (collectively referred to as a layered metal connection structure 21) of a printed circuit board, which is exposed by removing the layered insulating structure 3 through etching. The length h of the easily deformable portion is greater than the thickness t to ensure sufficient flexibility. Preferably, the length h of the easily deformable portion is greater than twice the thickness t.

[0034] In some other embodiments, such as Figure 3A and Figure 3B As shown, the layered metal connection structure corresponding to the deformable part 2 is a multi-layer stacking arrangement, which can effectively increase the welding area. The gaps between the multi-layer stacking provide welding exhaust channels, thereby improving the feasibility of the welding process. When at least two adjacent layered metal connectors in a multi-layer stacking arrangement are the same electrode, the gaps between adjacent stacked layers can block the crack propagation path of the solder joint, thereby effectively increasing the connection reliability. It should be noted that the wiring of different layers can be connected through the vias of the printed circuit board to achieve interconnection between different layers. Or as Figure 3C The second deformable portion is shown as a multi-layer staggered arrangement to meet the needs of different pin arrangements. It should be noted that the thickness of each layered metal and the thickness of the insulating dielectric layer between the metal layers can be freely set according to the through-current, insulation distance, process space required for pin grouping, etc.

[0035] In some other embodiments, such as Figure 4 As shown, the easily deformable portion 2 is a hole inner wall metal layer (e.g., through-hole inner wall metal layer 22) before the layered insulating structure is etched, further reducing the rigidity of the easily deformable metal structure, making it easier to deform, facilitating the pressing and leveling of the assembly structure, and improving the flatness of the assembly structure. At the same time, since the area of ​​the hole inner wall metal is large, the welding surface connection can be effectively increased, the welding strength can be increased, and the reliability can be improved.

[0036] In a preferred embodiment, if Figure 5 As shown, the hole inner wall metal layer is a segmented hole inner wall metal layer 23 to increase the number of pin fan-outs and improve the interconnection density.

[0037] In some other embodiments, such as Fig. 6A and Figure 6B As shown, Figure 6B for Fig. 6A The front view of the printed circuit board after etching, the deformable part is a combination of the layered metal connection structure and the hole inner wall metal layer 24 before the layered insulating structure is etched. At this time, the welding area can be further increased to increase the flexibility of the deformable part.

[0038] In some other embodiments, such as FIG. 7A to FIG. 7B As shown, the longitudinal electrical connector 1 may also have only the first easily deformable portion 25 or only the second easily deformable portion 26, and the end without the easily deformable portion is flush.

[0039] In a preferred embodiment, if Fig. 8A and Figure 8B As shown, the number and position of the electrodes at the upper end of the longitudinal electrical connector (a dotted box in the figure represents an electrode) may be consistent with or inconsistent with the number and position of the electrodes at the lower end (when the number of electrodes is inconsistent, the extra electrodes may be multiple electrodes of the same polarity, or may be used to bridge the positions where external components connected to the connector need to be interconnected); the electrode morphology is diverse, and the deformable portions of the array in the thickness direction may be the same electrode, or they may be grouped; they may be copper plating on the surface / inner layer of a printed circuit board, or they may be a through-hole metallization layer. They can be freely combined, and the shape of the resulting connector will also be diverse. By designing the electrodes of the longitudinal electrical connector, this embodiment can make full use of the advantages of flexible internal wiring of the connector, increase the pin arrangement density, and at the same time improve the flatness of the assembly structure and enhance welding reliability.

[0040] On the other hand, this embodiment discloses the application of the longitudinal electrical connector 1, such as 9A to 9C As shown, Fig. 9B for Fig. 9A The main view, Fig. 9C for Fig. 9A Top view of Fig. 9C Only the soldering pad 42 of the large-volume component 41 is shown, and the soldering pads of the remaining components are not shown). The longitudinal electrical connector 1 and the large-volume component 41 of the power module are fixedly connected by bonding materials to form an assembly 4; the top surface and / or the bottom surface of the large-volume component 41 is provided with a soldering pad 42, and the height difference (height tolerance) between the end height of the longitudinal electrical connector 1 and the corresponding height of the soldering pad 42 after leveling is less than 50μm.

[0041] like Fig.9D As shown, the leveling method can be flattening the entire surface (elastic gaskets can be added to prevent hard contact with stress-sensitive parts), or Fig.9E The scraper shown is scraped flat to one side (if the longitudinal electrical connector 1 is only provided with a deformable portion at one end, the end surface of the other end is first aligned with the plane where the welding pad corresponding to the large-volume component 41 is located during assembly).

[0042] After the assembly is formed, further steps such as Fig.10 As shown, the power module also includes a top component and a bottom component 6, the top component includes a top plate 51 and a power chip 52 and a capacitor element 53 arranged on the top plate, and the bottom component 6 includes a bottom plate, and the top plate and the bottom plate are respectively welded to the top surface and the bottom surface of the assembly 4.

[0043] 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.

[0044] 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 longitudinal electrical connector based on a printed circuit board, characterized in that: The longitudinal electrical connector includes a layered insulating structure and a metal connector arranged in the layered insulating structure; at least one end of the metal connector has an easily deformable portion exposed to the layered insulating structure, and the easily deformable portion is exposed by etching the layered insulating structure on a printed circuit board.

2. The longitudinal electrical connector according to claim 1, characterized in that The deformable portion is a layered metal connection structure before the layered insulating structure is etched.

3. The longitudinal electrical connector according to claim 1, characterized in that The deformable portion is a metal layer on the inner wall of the hole before the layered insulating structure is etched.

4. The longitudinal electrical connector according to claim 1, characterized in that The deformable portion is a combination of a layered metal connection structure and a metal layer on the inner wall of the hole before the layered insulating structure is etched.

5. The longitudinal electrical connector according to claim 2, characterized in that: The length of the easily deformable portion is greater than twice the thickness.

6. The longitudinal electrical connector according to claim 2, characterized in that: The layered metal connection structure corresponding to the deformable portion is a multi-layer stacked arrangement or a multi-layer staggered arrangement.

7. The longitudinal electrical connector according to claim 3 or 4, characterized in that: The hole inner wall metal layer is a through hole inner wall metal layer or a segmented hole inner wall metal layer.

8. The longitudinal electrical connector according to claim 1, characterized in that At least two easily deformable portions adjacent to each other in the thickness direction correspond to the same electrode.

9. Use of a longitudinal electrical connector according to any one of claims 1 to 8, characterized in that: The longitudinal electrical connector is used in a power module, which includes at least one longitudinal electrical connector and at least one large-volume component. The longitudinal electrical connector is arranged on at least one side of the large-volume component. The longitudinal electrical connector and the large-volume component form an assembly. The upper end and / or the lower end of the longitudinal electrical connector is leveled so that the height tolerance between the end face of the easily deformable portion and the welding surface of the large-volume component is less than or equal to 50μm.

10. The use according to claim 9, characterized in that: The power module also includes a top component and a bottom component. The top component includes a top plate and a power chip and a capacitor element arranged on the top plate. The bottom component includes a bottom plate. The top plate and the bottom plate are welded to the top surface and the bottom surface of the assembly respectively.

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