Integrated tantalum capacitor bearing structure

Abstract

The utility model discloses an integrated tantalum capacitor bearing structure which comprises a bearing copper table which is of an integrally-formed stepped structure, the top of the bearing copper table is coated with a nickel-gold layer, the bottom of the bearing copper table is coated with an OSP organic welding film, and the interior of the bearing copper table is filled with an epoxy glass fiber board and resin. According to the integrated tantalum capacitor bearing structure, pure metal copper serves as a loop for conduction, an iron-nickel alloy is replaced for conduction, the number of traditional tantalum capacitor combination parts is effectively reduced through the integrated tantalum capacitor bearing structure, traditional lead frame conduction is removed through plated-through holes, the product appearance is effectively reduced, the integration degree is improved, and the ESR of a finished product is effectively reduced; the electric leakage problem is avoided, a bottom drilling leading-out structure is used for replacing a traditional side leading-out structure, an integrated circuit board is used for replacing multiple parts of the traditional structure, and the side frame is prevented from occupying the space in the horizontal direction.

Description

Technical Field

[0001] The utility model belongs to the technical field of tantalum capacitors, and in particular relates to an integrated tantalum capacitor bearing structure. Background Art

[0002] Tantalum capacitors, as a type of electrolytic capacitors, are widely used in various electronic products, especially some products with high-density assembly and small internal space, such as mobile phones, portable printers, etc. SMD tantalum capacitors use metal tantalum (Ta) as the anode material, and can be divided into foil type and tantalum sintered powder type according to the different anode structures. Among the tantalum powder sintered tantalum capacitors, they can be divided into solid electrolyte tantalum capacitors and non-solid electrolyte tantalum capacitors due to different working electrolytes. Among them, solid tantalum electrolytic capacitors are the most used. Since tantalum capacitors use metal tantalum as the dielectric, they do not need to use electrolyte like ordinary electrolytic capacitors. In addition, SMD tantalum capacitors do not need to be fired with aluminum-coated capacitor paper like ordinary electrolytic capacitors, so they have almost no inductance, but this also limits its capacity.

[0003] The basic internal components of traditional tantalum capacitors are tantalum metal, tantalum pentoxide, manganese dioxide or polymer, graphite silver paste layer, silver paste bonding layer, lead layer and others. The internal structure of tantalum metal is the anode layer, which is formed by pressing and sintering metal powder. The internal structure of tantalum pentoxide is mainly the dielectric layer, which is formed by chemical treatment on the surface of the anode metal. The internal structure of manganese dioxide or polymer is the cathode layer, which is formed by thermal decomposition of manganese nitrate or polymerization of organic matter. The internal structure of graphite silver paste layer and silver paste bonding layer is the auxiliary cathode layer, which is formed by impregnation and drying of graphite and silver paste respectively. The internal structure of the silver paste bonding layer is to connect the core block and the lead metal, where the silver paste layer corresponds to the molded plastic encapsulation product, or the tin-wrapped layer corresponds to the resin encapsulation product, or the molten tin layer corresponds to the metal encapsulation product. The lead layer and others are mainly lead metal structures such as lead frames, CP wires, etc.

[0004] From the above structure, we can see that there are many limitations in the traditional tantalum capacitor structure. Our company intends to optimize the traditional structure in combination with the characteristics of the circuit board. From the analysis of the traditional structure, we can see that the capacitor of the traditional structure occupies a large space, and the factors that make miniaturization difficult are mainly:

[0005] 1. The molded epoxy resin shell has no support and is too thick, which affects the miniaturization of the product;

[0006] 2. The lead frame design structure is complex, and the middle extension design affects the space utilization in the left and right directions. Utility Model Content

[0007] The purpose of the utility model is to provide an integrated tantalum capacitor bearing structure to solve the technical defects of the existing integrated tantalum capacitor bearing structure, such as the epoxy resin shell molded has no support, is too thick, affects the miniaturization of the product, has a complex lead frame design structure, and has a middle extension design that affects the space utilization in the left and right directions.

[0008] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an integrated tantalum capacitor bearing structure, including a bearing copper platform, which is an integrally formed stepped structure, the top of the bearing copper platform is coated with a nickel-gold layer, the bottom of the bearing copper platform is coated with an OSP organic solder film, and the interior of the bearing copper platform is filled with epoxy glass fiber board and resin.

[0009] As a further solution of the utility model, an anode connection surface is provided on the upper part of one side of the higher step on the supporting copper platform, and the surface mount device on the anode connection surface is connected to the tantalum wire;

[0010] A cathode connection surface is arranged at the lower part of one side of a higher step on the supporting copper platform, and a surface mount device on the cathode connection surface is connected with the tantalum block.

[0011] As a further solution of the utility model, a through hole is formed on the epoxy glass fiber board, and the anode pin on the anode connection surface passes through the through hole and is led out from the groove at the bottom of the supporting copper platform together with the cathode pin on the cathode connection surface.

[0012] As a further solution of the utility model, a non-functional pad is provided at the bottom of the bearing copper platform, and a glass fiber reinforced plastic sleeve is provided on the fixed sleeve of the non-functional pad.

[0013] As a further solution of the utility model, the outer surface of the glass fiber reinforced plastic sleeve is coated with a solder resist layer.

[0014] As a preferred solution of the utility model, the thickness of the OSP organic solder film is 0.2-0.5um.

[0015] Compared with the prior art, the integrated tantalum capacitor bearing structure provided by the utility model has the following beneficial effects:

[0016] 1. The utility model adopts an integrated tantalum capacitor bearing structure and uses pure metal copper as a loop conduction to replace the iron-nickel alloy conduction method. The integrated tantalum capacitor bearing structure effectively reduces the number of components of the traditional tantalum capacitor assembly, and removes the traditional lead frame conduction with metallized holes, which not only effectively reduces the product appearance and improves the integration, but also effectively reduces the ESR of the finished product and avoids the leakage problem.

[0017] 2. The utility model replaces the traditional side lead-out structure with a bottom drilled lead-out structure, and replaces multiple components of the traditional structure with an integrated integrated circuit board, thereby avoiding the side frame from occupying space in the horizontal direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the embodiment of the utility model, the drawings required for use in the embodiment will be briefly introduced below. Obviously, the drawings described below are only examples of the embodiment of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a side view structural schematic diagram of an embodiment of the utility model;

[0020] Figure 2 It is a schematic cross-sectional structure diagram of an embodiment of the utility model.

[0021] Reference numerals:

[0022] 1. Carrying copper platform; 11. Anode connection surface; 12. Cathode connection surface; 2. Nickel-gold layer; 3. OSP organic solder film; 4. Glass fiber reinforced plastic sleeve; 5. Epoxy glass fiber board; 6. Resin. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiment of the utility model more clear, the embodiment of the utility model is further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0024] In the description of the embodiments of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the embodiments of the present invention.

[0025] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, an integral connection, or a detachable connection; it can be the internal connection of two components; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0026] See also Figure 1-Figure 2The utility model embodiment provides an integrated tantalum capacitor bearing structure, including a bearing copper platform 1, which is an integrally formed stepped structure, the top of the bearing copper platform 1 is coated with a nickel-gold layer 2, the bottom of the bearing copper platform 1 is coated with an OSP organic solder film 3, and the interior of the bearing copper platform 1 is filled with an epoxy glass fiber board 5 and a resin 6.

[0027] Through the above technical solution, pure metal copper is used as the circuit conduction to replace the iron-nickel alloy conduction method. The integrated tantalum capacitor bearing structure effectively reduces the number of traditional tantalum capacitor assembly components, and the traditional lead frame conduction is removed by metallized holes. It not only effectively reduces the product appearance and improves the integration, but also effectively reduces the ESR of the finished product to avoid leakage problems.

[0028] On the basis of the above technical solution, an anode connection surface 11 is provided on the upper part of the higher step of the supporting copper platform 1, and the surface mount device on the anode connection surface 11 is connected to the tantalum wire; a cathode connection surface 12 is provided on the lower part of the higher step of the supporting copper platform 1, and the surface mount device on the cathode connection surface 12 is connected to the tantalum block.

[0029] Through the above technical solution, the connection part between the traditional lead frame anode and the tantalum wire is replaced by a higher TOP surface surface mount device design, and the connection part between the cathode and the tantalum block is replaced by a lower TOP surface surface mount device design, forming an integrated PCB bearing structure.

[0030] The epoxy glass fiber board 5 is provided with a through hole, and the anode pin on the anode connection surface 11 passes through the through hole and is led out from the bottom groove of the supporting copper platform 1 together with the cathode pin on the cathode connection surface 12 .

[0031] Changing the electrode lead-out method from the two sides to the bottom leads not only improves the electrical conductivity of the conductor, but also shortens the conductive loop and avoids the horizontal space occupation by the side frame.

[0032] The bottom of the supporting copper platform 1 is provided with a non-functional pad, and a glass fiber reinforced plastic sleeve 4 is fixed on the non-functional pad.

[0033] The process strength and insulation withstand voltage performance are improved by combining glass fiber and resin, thereby reducing the thickness of the insulation shell and achieving a smaller Z-axis dimension.

[0034] The outer surface of the glass fiber reinforced plastic sleeve 4 is coated with a solder resist layer, which can prevent solder from adhering to specific areas of the PCB surface. Only the designated areas where the components are to be connected can receive solder, which can prevent solder from entering the rest of the circuit, thereby reducing the possibility of solder bridges that may cause short circuits.

[0035] The thickness of the OSP organic solder film 3 is 0.2-0.5um, preferably 0.3um, to prevent the copper surface from being oxidized before soldering and to protect the solderability of the PCB pad from being damaged.

[0036] The working principle of the utility model is to integrate the structural components with the help of the PCB platform to form a stepped structure with ultra-thick copper characteristics, thus realizing the integrated load-bearing mode and modular packaging function of the tantalum capacitor;

[0037] Low ESR technology, developing pure metal electroplating bosses and laser through-hole technology, changing the side lead-out form of the frame lead to bottom electrode lead-out, on the one hand to improve the conductivity of the conductor, on the other hand to shorten the conductive loop, achieving the effect of reducing ESR.

[0038] The above shows and describes the basic principles of the present invention. The above are only preferred embodiments of the present invention and are not intended to limit the present invention. The above embodiments and descriptions in the specification are only intended to illustrate the principles of the present invention. Without departing from the scope of the present invention, any modifications, equivalent substitutions and improvements made within the spirit and scope of the present invention should be included in the protection scope of the present invention.

Claims

1. An integrated tantalum capacitor bearing structure, characterized in that: The invention comprises a copper support platform (1) which is an integrally formed stepped structure; the top of the copper support platform (1) is coated with a nickel-gold layer (2); the bottom of the copper support platform (1) is coated with an OSP organic solder film (3); and the interior of the copper support platform (1) is filled with an epoxy glass fiber board (5) and a resin (6).

2. The integrated tantalum capacitor support structure according to claim 1, characterized in that: An anode connection surface (11) is provided on the upper part of one side of the higher step on the supporting copper platform (1), and the surface mounted device on the anode connection surface (11) is connected to the tantalum wire; A cathode connection surface (12) is provided at the lower part of one side of the higher step on the supporting copper platform (1), and a surface mounted device on the cathode connection surface (12) is connected to a tantalum block.

3. The integrated tantalum capacitor support structure according to claim 2, characterized in that: The epoxy glass fiber board (5) is provided with a through hole, and the anode pin on the anode connection surface (11) passes through the through hole and is led out from the bottom groove of the supporting copper platform (1) together with the cathode pin on the cathode connection surface (12).

4. The integrated tantalum capacitor support structure according to claim 3, characterized in that: The bottom of the supporting copper platform (1) is provided with a non-functional solder pad, and a glass fiber reinforced plastic sleeve (4) is fixedly provided on the non-functional solder pad.

5. The integrated tantalum capacitor support structure according to claim 4, characterized in that: The outer surface of the glass fiber reinforced plastic sleeve (4) is coated with a solder resist layer.

6. The integrated tantalum capacitor support structure according to claim 1, characterized in that: The thickness of the OSP organic solder film (3) is 0.2-0.5 um.

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