Vertical SMD (Surface Mounted Device) element packaged by plastic shell

Abstract

A vertical SMD element packaged by a plastic shell comprises a chip, an outer electrode and a packaging plastic shell, two inner electrode contacts of the chip are located on any two opposite surfaces, and porcelain bodies are arranged on the peripheries of the inner electrode contacts; the outer electrode is conductive metal which can be bent and formed, the two outer electrode contacts are in contact with the two inner electrode contacts, the two outer electrode pins are led out towards the same side and are mutually separated and turned over, and the inner sections of the two outer electrode pins are bent once and are wrapped and fixed by the packaging plastic shell. The packaging plastic shell is in the shape of a quadrangular prism or a hexagonal prism, the outer sections of the two outer electrode pins are bent along the outer surface of the packaging plastic shell to form at least one wall attaching section, and the two wall attaching sections are arranged in a spaced mode. Different from a common mode that the SMD is installed on a circuit board in a flat mode, space occupied by the SMD on the circuit board is saved through vertical installation, the effective size of the whole SMD occupied by the ceramic chip is increased, the electrical performance of the SMD element under the same size is improved, and the SMD element industrial production is easier to achieve the consistency of standard requirements.

Description

Technical Field

[0001] The utility model relates to the field of electrical components, in particular to a vertical SMD component packaged in a plastic shell. Background Art

[0002] With the adoption and continuous development of microelectronic circuits and surface mount technology (SMT), light, thin and small have become important indicators for measuring electronic products. To miniaturize electronic equipment, the first thing to consider is the miniaturization of electronic components.

[0003] At present, there is a type of surface mount (SMD) component, such as a small chip-type surface mount (SMD) high-voltage, safety ceramic capacitor disclosed in ZL201510070008.X. In order to provide a larger welding site and reduce the occupied space in the vertical direction, this type of capacitor uses the upper and lower steel strip pins as external electrodes for welding, and then reversely leads the external electrodes, folds them outward in a curved direction, and then extends outward along the middle of the packaging shell. In the actual production of such products, during the process of thermosetting compression molding of the resin material, local cavitation may occur in the curved folding part, resulting in uneven stress distribution of the outer electrode due to uneven packaging plastic material, which may easily cause the outer electrode to bend and twist when subjected to compression force. When this happens in the folding area of ​​the outer electrode, it is more likely to cause failure and even safety hazards. For example, when the outer electrode is deformed and contacts the ceramic medium, the outer electrode will contact the inner electrode and the ceramic medium at the same time, causing component failure and reducing the qualified rate, which can be effectively eliminated by the detection device; if the outer electrode is too close to the ceramic medium, it is difficult to effectively eliminate it during detection by the detection device and is therefore certified as a "qualified" product. However, when such components undergo transient changes in the load current of the equipment, they are prone to sparking and breakdown, posing a greater safety hazard.

[0004] In order to effectively reduce the occurrence of the external electrode touching the ceramic medium, the current technical solutions mostly extend the length of the external electrode in the horizontal direction and increase the gap of the resin material to reduce the external electrode from contacting the ceramic medium due to the random material stress during the thermal curing process of the plastic shell, which causes the external electrode to deform. However, this also causes the components to occupy too much space on the PCB board, which is not conducive to the effective miniaturization of the components. Summary of the invention

[0005] The utility model aims to provide a vertical SMD component encapsulated in a plastic shell, which can effectively reduce the volume occupied by the plastic used as the encapsulation by modifying the encapsulation plastic shell and the external electrode construction method, so that the production of SMD components can meet the consistency of industrial standards.

[0006] In order to achieve the above purpose, the utility model adopts the following technical means to implement:

[0007] A vertical SMD component packaged in a plastic shell includes a chip, an external electrode, and a packaging plastic shell. The two internal electrode contacts of the chip are located on any two opposite surfaces, and the outer periphery of the internal electrode contacts has a ceramic body; the external electrode is a conductive metal that can be bent and formed, the two external electrode contacts are in contact with the two internal electrode contacts, the two external electrode pins are led out to the same side and folded away from each other, and the inner sections of the two external electrode pins are bent once and fixed by the packaging plastic shell. The packaging plastic shell is a quadrangular prism or a hexagonal prism, the outer sections of the two external electrode pins are bent along the outer surface of the packaging plastic shell to form at least one wall-attached section, and the two wall-attached sections are arranged apart. Specifically, inside the packaging plastic shell, the external electrode contacts and the inner sections of the external electrode pins are bent once in an "L" shape, thereby avoiding the common external electrode folding design. During injection molding, due to the extrusion of the plastic packaging material, the external electrode pins are bent and twisted when subjected to compression force and touch the ceramic body, causing the product insulation to decrease or even short-circuit failure. Safety risks.

[0008] The external electrode can be made of a bendable conductive metal wire, a thin sheet, or a combination of the two. For example, by selecting a thin sheet-shaped external electrode contact and a linear external electrode pin conductive metal wire structure, as a further improvement, the external electrode is made of a bendable conductive metal sheet, which has the advantages of stable angle after bending and a higher contact area with the solder joint and the internal electrode contact, and is easy to process, and can effectively improve the pass rate in mass production.

[0009] Furthermore, the external electrode contacts of the inner sections of the two external electrode pins are folded away from each other so that the angle between the inner sections of the external electrode pins and the surface where the external electrode contacts are located is 90°±45°; further, the angle between the inner sections of the external electrode pins and the surface where the external electrode contacts are located is 90°±25°.

[0010] Furthermore, the ends of the outer sections of the two outer electrode pins are bent toward or away from each other on the same horizontal plane.

[0011] Furthermore, the ends of the outer sections of the two outer electrode pins are bent toward or away from each other along the bottom wall of the packaging plastic shell.

[0012] Furthermore, the external electrode pins are arranged at the corners of the external electrode contacts.

[0013] Furthermore, along the plane where the external electrode contacts are located, the angle between the two external electrode pins is greater than or equal to 0° and less than 180°; further, the angle between the two external electrode pins is 15° to 165°.

[0014] Furthermore, the area ratio of the outer electrode contacts to the inner electrode contacts is between 25% and 90%.

[0015] Furthermore, the chip is one of a thermistor chip, a varistor chip, and a ceramic capacitor chip.

[0016] The utility model has at least the following benefits:

[0017] This technology arranges the chip component vertically, mounts the two outer electrode pins by double-side welding and leads them to the same side and folds them away from each other, and forms SMD components through plastic shell packaging. It can effectively reduce the occupied area of ​​the product in the horizontal direction, increase the effective volume occupied by the internal chip in the three-dimensional structure, and improve the electrical performance of SMD components with the same volume size;

[0018] The inner section of the external electrode pin is bent only once inside the packaging plastic shell, which can avoid the formation of cavitation due to the external electrode pin bending to the folded part in the prior art, and the polymer plastic in a hot melt state cannot fully penetrate into this part. It can also avoid the external electrode pin being bent or twisted during the molding of the packaging plastic shell and contacting with the porcelain body, thereby preventing chip failure, thereby meeting the desired effect of achieving a high pass rate and consistency with industrial standards in the production of SMD components. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the outer electrodes of Example 1 and Example 2;

[0020] Figure 2 is a schematic diagram of the chip;

[0021] Figure 3 It is a first horizontal perspective schematic diagram of Embodiment 1 of the present utility model;

[0022] Figure 4 It is a second horizontal perspective schematic diagram of Embodiment 1 of the present utility model;

[0023] Figure 5 It is a three-dimensional perspective schematic diagram of embodiment 1 of the utility model;

[0024] Figure 6 It is a first horizontal perspective schematic diagram of Embodiment 2 of the present utility model;

[0025] Figure 7 It is a second horizontal perspective schematic diagram of Embodiment 2 of the present utility model;

[0026] Figure 8 Schematic diagram of the outer electrode of Example 3;

[0027] Fig. 9 It is a horizontal perspective schematic diagram of Embodiment 3 of the present utility model;

[0028] Fig.10 It is a three-dimensional perspective schematic diagram of Embodiment 3 of the present utility model;

[0029] Fig.11 It is a three-dimensional perspective schematic diagram of embodiment 4 of the present utility model. DETAILED DESCRIPTION

[0030] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0031] It should be noted that all directional indications (such as up, down, left, right, front, back, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] The present invention is further described in detail below with reference to specific embodiments and accompanying drawings: Example 1

[0033] like Figure 1-5 As shown, a vertical SMD component of a plastic shell package, whose chip is a (3220, 4020, 6020) thermistor chip, two inner electrode contacts 21 of the chip are located on two opposite surfaces, and the outer periphery of the inner electrode contact 21 has a ring-shaped porcelain body 22; the outer electrode 3 is a conductive metal sheet that can be bent and formed (such as a conductive metal sheet such as copper, silver, nickel, etc.), the outer electrode contact 31 is rectangular and the outer electrode pin is arranged at the corner side of the outer electrode contact 31, and the area of ​​the outer electrode contact 31 is 66%-75% of the area of ​​the inner electrode contact 21; the two outer electrode contacts 31 are welded to the two inner electrode contacts 21, so that along the plane where the outer electrode contact 31 is located, the angle σ1 between the two outer electrode pins is 60°±2.5°. The two external electrode pins are led out to the same side and folded away from each other, so that the first bending angle α1 between the inner section 32 of the external electrode pin and the external electrode contact 31 is 130°±2.5°, and then the two external electrode pins are bent along the AA fold line to form a vertical bend to form a second bending angle β1, and then folded back horizontally relative to each other to form a third bending angle γ1, forming a pre-folded pin chip.

[0034] By using a hot-melt polymer material as a packaging material and solidifying it to form a quadrangular prism, the two outer electrode pin inner sections 32 and the first bending angle α1 are enclosed and fixed by the packaging plastic shell, the second bending angle β1 is bent from the inside of the packaging plastic shell to the outer wall, and the third bending angle γ1 is bent from the outer wall of the packaging plastic shell to the bottom wall, and the outer electrode pin outer section 33 is formed from the second bending angle β1 to the end of the external electrode 3, and the two outer electrode pin outer sections 33 are arranged to be separated from each other.

[0035] Product related technical parameters

[0036] Product Model Overall dimensions (mm) length × height × thickness Inner and outer electrode contact area ratio External electrode pin length External electrode lead width B value Dissipation coefficient (mw / ℃) Qualified rate (10,000 pieces) Example 1-1 3220 8.1×5.0×5.9 40% 3.8mm 1.5mm 2700K 9 99.9% Example 1-2 4020 10.2×8.2×5.9 50% 5.3mm 2.0mm 2700K 11 99.9% Examples 1-3 6020 15.5×10.2×5.9 55% 5.5mm 3.0mm 2700K 15 99.9% Example 2

[0037] like Figure 1 , 2 , 6, and 7, a vertical SMD component with a plastic shell package, whose chip is a (3220, 4020, 6020) ceramic capacitor chip, the two inner electrode contacts 21 of the chip are located on two opposite surfaces, and the outer periphery of the inner electrode contact 21 has a ring-shaped ceramic body 22; the outer electrode 3 is a conductive metal sheet that can be bent and formed, that is, the outer electrode contact 31 is rectangular and the outer electrode pin is arranged at the corner side of the outer electrode contact 31, and the area of ​​the outer electrode contact 31 is 67%-69% of the area of ​​the inner electrode contact 21; the two outer electrode contacts 31 are welded to the two inner electrode contacts 21, so that along the plane where the outer electrode contact 31 is located, the angle σ2 between the two outer electrode pins is 45°±1.5°. The two external electrode pins are led out to the same side and folded away from each other, so that the first bending angle α2 between the inner section 32 of the external electrode pin and the external electrode contact 31 is 90°±1.5°, and then the two external electrode pins AA are folded to form a bend in the vertical direction to form a second bending angle β2, and then folded back horizontally relative to each other to form a third bending angle γ2, forming a pre-folded pin chip.

[0038] By using a hot-melt polymer material as a packaging material and solidifying it to form a hexagonal prism, the inner sections 32 of the two outer electrode pins and the first bending angle α2 are enclosed and fixed by the packaging plastic shell, the second bending angle β2 is vertically bent from the inside of the packaging plastic shell and a certain distance 4 is left between the outer wall of the packaging plastic shell, and the third bending angle γ2 is bent toward the bottom wall inside the packaging plastic shell, and the outer section 33 of the outer electrode pin is formed from the second bending angle β2 to the end of the outer electrode 3, and the two outer sections 33 of the outer electrode pin are arranged to be separated from each other. When the reflow soldering process is performed, when the welding material contacts and solidifies with the external electrode pin, the molten welding material can flow along the distance 4 between the outer walls of the packaging plastic shell and solidify to form a stable embedded welding site, which can improve the welding stability of the SMD component.

[0039] Product related technical parameters

[0040] Product Model Overall dimensions (mm) length × height × thickness Inner and outer electrode contact area ratio External electrode pin length External electrode lead width Nominal Capacitance Loss tangent Rated voltage Qualified rate (10,000 pieces) Example 2-1 3220 8.1×5.0×5.9 40% 3.8mm 1.5mm 0.022μF 0.033%~0.038% 400VAC 99.9% Example 2-2 4020 10.2×8.2×5.9 40% 5.3mm 2.0mm 0.0047μF 0.043%~0.058% 400VAC 99.9% Example 2-3 6020 15.5×10.2×5.9 40% 5.5mm 3.0mm 0.033μF 0.031%~0.035% 250VAC 99.9% Example 3

[0041] like Figure 8-10 As shown ( Fig.10Only the outer electrode pin on one side of the near-sight side is shown in perspective), a vertical SMD component encapsulated in a plastic shell, whose chip is a (3220, 4020, 6020) varistor chip, and the two inner electrode contacts 21 of the chip are located on two opposite surfaces, and the outer periphery of the inner electrode contact 21 has a ring-shaped porcelain body 22; the outer electrode 3 is a conductive metal sheet that can be bent and formed, and its overall shape is sheet-like, and its outer electrode pin is straight before being bent, and the area of ​​the outer electrode contact 31' is 59.5%-81.5% of the area of ​​the inner electrode contact 21; the two outer electrode contacts 31' are welded to the two inner electrode contacts 21. The two external electrode pins are led out to the same side and folded away from each other, so that the first bending angle between the inner section 32' of the external electrode pin and the external electrode contact 31' is 90°±1.5°, and then the two external electrode pins are bent along the BB fold line to form a bend in the vertical direction to form a second bending angle, and then folded horizontally outward relative to each other to form a third bending angle, forming a pre-folded pin chip.

[0042] By using a hot-melt polymer material as a packaging material and solidifying it to form a quadrangular prism, the two outer electrode pin inner sections 32' and the first bending angle are enclosed and fixed by the packaging plastic shell, the second bending angle is bent from the inside of the packaging plastic shell to the outer wall, and the third bending angle is bent outward along the bottom wall of the outer wall of the packaging plastic shell, and the outer electrode pin outer section 33' is formed from the second bending angle to the end of the outer electrode 3, and the two outer electrode pin outer sections 33' are arranged to be separated from each other.

[0043] Product related technical parameters

[0044] Product Model Nominal varistor voltage Overall dimensions (mm) length × height × thickness Inner and outer electrode contact area ratio External electrode pin length External electrode lead width Current capacity (Vn / 40 times) Maximum allowable voltage Qualified rate (10,000 pieces) Example 3-1 3220 430V 8.1×5.0×5.9 40% 3.8mm 1.5mm 2kV / 1kA AC 275V 99.9% Example 3-2 4020 470V 10.2×8.2×5.9 50% 5.3mm 2.0mm 4kV / 2kA AC 300V 99.9% Example 3-3 6020 510V 15.5×10.2×5.9 55% 5.5mm 3.0mm 6kV / 3kA AC 320V 99.9% Example 4

[0045] like Fig.11 As shown ( Fig.11 Only the outer electrode pin on one side of the near-sight side is shown in perspective), a vertical SMD component encapsulated in a plastic shell, the chip of which is a (5020) varistor chip, the two inner electrode contacts 21 of the chip are located on two opposite surfaces, and the outer periphery of the inner electrode contact 21 has a ring-shaped porcelain body 22; the outer electrode 3 * The conductive metal wire is bendable and has a linear shape. * The area of ​​the inner electrode contact 21 is 5% of the area of ​​the two outer electrode contacts 31. * The two outer electrode pins are led out to the same side and folded away from each other, so that the inner section 32 of the outer electrode pin is welded to the two inner electrode contacts 21. * With external electrode contact 31 *The first bending angle α4 between them is 120°±0.5°, and then the two outer electrode pins are bent to form a second bending angle β4 of 120°±0.5°, and they are folded horizontally relative to each other to form a third bending angle γ4 to form a pre-folded pin chip.

[0046] By using a hot-melt polymer material as a packaging material and solidifying it to form a quadrangular prism, the inner section 32 of the two outer electrode pins * The first bending angle α4 is enclosed and fixed by the packaging plastic shell, and the second bending angle β4 is bent from the inside of the packaging plastic shell to the outer wall. In addition, this embodiment also performs a right-angle bend in the section from the second bending angle β4 to the third bending angle γ4 to enhance the overall contact surface of the conductive metal wire, and then from the outer section 33 of the external electrode pin * From the third bending angle γ4, bend outward along the bottom wall of the packaging plastic shell, from the second bending angle β4 to the outer electrode 3 * The end forms an outer electrode pin outer section 33 * , and the outer sections 33 of the two outer electrode pins * They are set apart from each other.

[0047] Product related technical parameters

[0048] Product Model Nominal varistor voltage Overall dimensions (mm) length × height × thickness Inner and outer electrode contact area ratio External electrode pin length Outer electrode pin diameter Current capacity (Vn / 40 times) Maximum allowable voltage Qualified rate (10,000 pieces) Example 4 5020 560V 12.7×10.2×5.9 5% 5.3mm Φ0.8mm 6kV / 3kA AC 350V 99.9%

[0049] Through the schemes of the above four embodiments, the shape of the external electrode pins is reasonably changed. The schemes of embodiments 1 and 2 can make the external electrode pins lead out from the same bottom surface of the packaging plastic shell, reduce the position occupied by the extra electrode pins on the circuit board, and are suitable for reflow soldering on the circuit board to achieve surface mounting; the scheme of embodiment 3 can make the external electrode pins lead out from both sides of the packaging plastic shell, with a larger exposed welding site, which is suitable for surface mounting and reflow soldering on the circuit board; the scheme of embodiment 4 adopts a linear conductive metal wire, which is more convenient in the bending and forming process of the conductive metal wire compared with embodiments 1-3, and can effectively reduce the product processing cost. In addition, the wire is round and the interface with the plastic packaging material is small, which can better prevent moisture from invading the SMD product core and improve the product's moisture resistance.

[0050] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications of the above assumptions should also be regarded as the protection scope of the present invention.

Claims

1. A vertical SMD component encapsulated in a plastic shell, comprising a chip, an external electrode, and an encapsulated plastic shell, characterized in that: The two inner electrode contacts of the chip are located on any two opposite surfaces, and the outer periphery of the inner electrode contacts has a porcelain body; the outer electrode is a conductive metal that can be bent and formed, the two outer electrode contacts are in contact with the two inner electrode contacts, the two outer electrode pins are led out to the same side and folded away from each other, the inner sections of the two outer electrode pins are bent once and are wrapped and fixed by the packaging plastic shell, the packaging plastic shell is a quadrangular prism or a hexagonal prism, the outer sections of the two outer electrode pins are bent along the outer surface of the packaging plastic shell to form at least one wall-attached section, and the two wall-attached sections are arranged apart from each other.

2. The vertical SMD component encapsulated in a plastic shell as claimed in claim 1, characterized in that: The external electrode contacts of the inner sections of the two external electrode pins are folded away from each other so that the angle between the inner sections of the external electrode pins and the surface where the external electrode contacts are located is 90°±45°.

3. The vertical SMD component encapsulated in a plastic shell as claimed in claim 2, characterized in that: The external electrode contacts of the inner sections of the two external electrode pins are folded away from each other so that the angle between the inner sections of the external electrode pins and the surface where the external electrode contacts are located is 90°±25°.

4. The vertical SMD component encapsulated in a plastic shell as claimed in claim 2, characterized in that: The ends of the outer sections of the two outer electrode pins are bent toward or away from each other on the same horizontal plane.

5. The vertical SMD component encapsulated in a plastic shell as claimed in claim 4, characterized in that: The ends of the outer sections of the two outer electrode pins are bent toward or away from each other along the bottom wall of the packaging plastic shell.

6. The vertical SMD component encapsulated in a plastic shell as claimed in claim 1, characterized in that: The external electrode pins are arranged at the corner sides of the external electrode contacts.

7. The vertical SMD component encapsulated in a plastic shell as claimed in claim 6, characterized in that: Along the plane where the external electrode contacts are located, the angle between the two external electrode pins is greater than or equal to 0° and less than 180°.

8. The vertical SMD component encapsulated in a plastic shell as claimed in claim 7, characterized in that: Along the plane where the external electrode contacts are located, the angle between the two external electrode pins is 15° to 165°.

9. The vertical SMD component encapsulated in a plastic shell as claimed in any one of claims 1 to 8, characterized in that: The area ratio of the outer electrode contact to the inner electrode contact is between 25% and 90%.

10. The vertical SMD component encapsulated in a plastic shell as claimed in any one of claims 1 to 8, characterized in that: The chip is one of a thermistor chip, a varistor chip, and a ceramic capacitor chip.

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