DFN packaging structure

Abstract

The utility model provides a DFN packaging structure, and relates to the field of packaging. The DFN packaging structure comprises a packaging box, a plurality of heat dissipation openings are formed in the two sides of the packaging box, filter screens are fixedly connected to the interiors of the heat dissipation openings, a heat dissipation mechanism is fixedly connected to the inner bottom face of the packaging box, a bonding pad is welded to the bottom face of the packaging box, and four sets of limiting columns are fixedly connected to the top face of the bonding pad. The bottom surface of the bonding pad is fixedly connected with a circuit board; the heat dissipation mechanism comprises a heat dissipation sheet fixedly connected to the inner bottom surface of the packaging box, the top surface of the heat dissipation sheet is fixedly connected with a heat conduction sheet, and two sides of the bonding pad are fixedly connected with a plurality of groups of pins. In consideration of the heat dissipation problem of the packaging structure, the heat dissipation mechanism is arranged on the bottom surface of the packaging box, and the heat dissipation openings are formed in the two sides of the packaging box, so that heat generated by the chip can be transmitted to the outside, equipment is protected from being damaged by overheating, and the performance and reliability of the equipment can be improved.

Description

Technical Field

[0001] This application relates to the field of packaging technology, and particularly to a DFN packaging structure. Background Art

[0002] DFN packaging is a modern surface mount technology packaging that is widely used in various electronic devices and allows one or more semiconductor devices to be connected within a lead-free package. The problem with the prior art is that during packaging, the packaging box is directly welded to the bottom pad and the whole is in a sealed state, which is not conducive to heat dissipation.

[0003] In the prior art during packaging, the welding between the packaging box and the bottom pad is not firm and the overall heat dissipation is poor. Heat dissipation is very important in electronic devices. It can not only protect the device from overheating hazards, but also improve the performance and reliability of the device and extend its service life. It is an indispensable part of modern electronic engineering design. Therefore, a DFN packaging structure is proposed. Summary of the Invention

[0004] This application provides a DFN packaging structure to solve the problems of poor welding between the packaging box and the bottom pad and poor overall heat dissipation.

[0005] This application provides a DFN packaging structure, including a packaging box, characterized in that: a plurality of heat dissipation openings are provided on both sides of the packaging box, filter nets are fixedly connected inside the heat dissipation openings, a heat dissipation mechanism is fixedly connected to the inner bottom surface of the packaging box, a pad is welded to the bottom surface of the packaging box, four groups of limit posts are fixedly connected to the top surface of the pad, and a circuit board is fixedly connected to the bottom surface of the pad; the heat dissipation mechanism includes heat dissipation fins fixedly connected to the inner bottom surface of the packaging box, and heat conduction sheets are fixedly connected to the top surfaces of the heat dissipation fins.

[0006] Preferably, a plurality of groups of pins are fixedly connected to both sides of the pad, and the pins are symmetrically distributed on both sides of the pad. The pins facilitate connection to the circuit board.

[0007] Preferably, a chip is fixedly connected to the top surface of the heat conduction sheet, and the chip is slightly smaller than the size of the heat conduction sheet, which is convenient for the heat conduction sheet to absorb the heat of the chip.

[0008] Preferably, the heat conduction sheet is made of silicone material and the heat conduction sheet is made of metal material, which is convenient for heat conduction.

[0009] Preferably, the filter net has a certain elasticity and does not affect the passage of air flow. The filter net is convenient for blocking dust from entering.

[0010] Preferably, four groups of limit openings are provided on the bottom surface of the packaging box, and the sizes of the limit openings are the same as those of the limit posts, which is convenient for positioning and installing the packaging box.

[0011] Preferably, a sliding opening is provided on the surface of the pad, and the depth of the sliding opening is consistent, which is convenient for ensuring the quality of the welding of the packaging box.

[0012] Beneficial effects:

[0013] Considering the heat dissipation problem of the packaging structure, a heat dissipation mechanism is provided on the bottom surface of the packaging box, and heat dissipation openings are provided on both sides of the packaging box, which can transfer the heat generated by the chip to the outside, protect the device from overheating, and improve the performance and reliability of the device; considering the stability problem of the packaging structure, a sliding opening is provided on the surface of the pad, which can increase the welding contact area, contribute to the uniform distribution and filling of the solder, and improve the reliability and strength of the welding; considering the accurate installation problem of the packaging structure, positioning posts are provided on the surface of the pad, which can accurately position and install the packaging box.

[0014] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to be able to understand the technical means of the embodiments of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and understandable, the following specifically illustrates the specific embodiments of the present application. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0016] Figure 1 It is a schematic diagram of the overall structure of a DFN packaging structure of the present invention.

[0017] Figure 2 It is a schematic diagram of the pad structure of a DFN packaging structure of the present invention.

[0018] Figure 3 It is a schematic diagram of the heat dissipation mechanism structure of a DFN packaging structure of the present invention.

[0019] Figure 4 It is a schematic diagram of the heat dissipation opening structure of a DFN packaging structure of the present invention.

[0020] Description of the reference numerals:

[0021] 1. Packaging box; 2. Heat dissipation opening; 3. Filter screen; 4. Heat dissipation mechanism; 401. Heat dissipation fin; 402. Heat conduction sheet; 5. Pad; 6. Positioning post; 7. Circuit board; 8. Pin; 9. Chip; 10. Limiting opening; 11. Sliding opening. Detailed implementation manners

[0022] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the drawings are intended to cover non-exclusive inclusion.

[0024] Reference to "embodiment" herein means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0025] The directional terms appearing in the following description are all the directions shown in the figures and do not limit the specific structure of this application. For example, in the description of this application, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of this application.

[0026] In addition, expressions indicating directions such as the X direction, Y direction, and Z direction used to illustrate the operations and structures of the components of this embodiment are not absolute but relative. Although these indications are appropriate when the components are in the positions shown in the figures, when these positions change, these directions should have different interpretations to correspond to the changes.

[0027] In addition, the terms "first", "second", etc. in the description and claims of this application or in the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order, and may explicitly or implicitly include one or more of such features.

[0028] In the description of this application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, the "connection" or "coupling" of mechanical structures may refer to a physical connection. For example, a physical connection may be a fixed connection, such as a fixed connection through a fixing member, such as a screw, bolt, or other fixing member; a physical connection may also be a detachable connection, such as a snap connection or a snap-fit connection; a physical connection may also be an integral connection, such as a welded, bonded, or integrally formed connection. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] In order to enable those skilled in the art of this technology to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the drawings.

[0030] The present utility model provides a DFN package structure as Figures 1-4 shown, which includes a package box 1. A plurality of heat dissipation openings 2 are provided on both sides of the package box 1. Filter nets 3 are fixedly connected inside the heat dissipation openings 2. A heat dissipation mechanism 4 is fixedly connected to the inner bottom surface of the package box 1. A solder pad 5 is welded to the bottom surface of the package box 1. Four groups of limit posts 6 are fixedly connected to the top surface of the solder pad 5. A circuit board 7 is fixedly connected to the bottom surface of the solder pad 5; the heat dissipation mechanism 4 includes a heat sink 401 fixedly connected to the inner bottom surface of the package box 1, and a heat conducting sheet 402 is fixedly connected to the top surface of the heat sink 401.

[0031] Wherein, a plurality of groups of pins 8 are fixedly connected to both sides of the solder pad 5. The pins 8 are symmetrically distributed on both sides of the pins 8, and the pins 8 facilitate the connection with the circuit board 7.

[0032] Wherein, a chip 9 is fixedly connected to the top surface of the heat conducting sheet 402. The chip 9 is slightly smaller than the size of the heat conducting sheet 402, which facilitates the heat conducting sheet 402 to absorb the heat of the chip 9.

[0033] Wherein, the heat conducting sheet 402 is made of silica gel material, and the heat conducting sheet 402 is made of metal material, which facilitates heat conduction.

[0034] Wherein, the filter net 3 has a certain elasticity and does not affect the airflow, and the filter net 3 facilitates blocking dust from entering.

[0035] Wherein, four groups of limit openings 10 are provided on the bottom surface of the package box 1. The size of the limit openings 10 is the same as that of the limit posts 6, which facilitates the positioning and installation of the package box 1.

[0036] Among them, a sliding opening 11 is provided on the surface of the pad 5, and the depth of the sliding opening 11 is consistent, which is convenient for ensuring the welding quality of the packaging box 1.

[0037] Working principle: When this DFN packaging structure is used, solder is applied on the pad 5 of the circuit board 7, and then the limiting opening 10 on the packaging box 1 is aligned with the limiting post 6 on the pad 5 and inserted. The existence of the sliding opening 11 can significantly increase the welding surface area. The solder can not only be applied on the flat surface of the pad 5, but also fill and cover the walls and bottom of the groove. Therefore, the welding area is larger than that of a flat surface, and the welding connection is more firm and reliable;

[0038] The heat on the chip 9 is absorbed by the heat conducting sheet 402 and then transferred to the outside by the heat sink 401. Moreover, heat dissipation openings 2 and filter nets 3 are provided on both sides of the packaging box 1. Part of the heat generated by the chip 9 during operation will also be dissipated through the heat dissipation openings 2, and the filter nets 3 can prevent external dust from entering.

[0039] As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A DFN packaging structure, comprising a packaging box (1), characterized in that: A plurality of heat dissipation openings (2) are provided on both sides of the packaging box (1), and filters (3) are fixedly connected inside the heat dissipation openings (2). A heat dissipation mechanism (4) is fixedly connected to the inner bottom surface of the packaging box (1). A soldering pad (5) is welded to the bottom surface of the packaging box (1), and four groups of limiting columns (6) are fixedly connected to the top surface of the soldering pad (5), and a circuit board (7) is fixedly connected to the bottom surface of the soldering pad (5); The heat dissipation mechanism (4) comprises a heat sink (401) fixedly connected to the inner bottom surface of the packaging box (1), and a heat conducting sheet (402) is fixedly connected to the top surface of the heat sink (401).

2. A DFN packaging structure according to claim 1, characterized in that: A plurality of groups of pins (8) are fixedly connected to both sides of the pad (5), and the pins (8) are symmetrically distributed on both sides of the pins (8).

3. The DFN packaging structure according to claim 1, characterized in that: A chip (9) is fixedly connected to the top surface of the heat conducting sheet (402), and the chip (9) is slightly smaller than the size of the heat conducting sheet (402).

4. The DFN packaging structure according to claim 1, characterized in that: The heat conducting sheet (402) is made of silicone material, and the heat conducting sheet (402) is made of metal material.

5. The DFN packaging structure according to claim 1, characterized in that: The filter screen (3) has a certain elasticity and does not affect the passage of airflow.

6. The DFN packaging structure according to claim 1, characterized in that: The bottom surface of the packaging box (1) is provided with four groups of limiting openings (10), and the size of the limiting openings (10) is consistent with the size of the limiting pillars (6).

7. The DFN packaging structure according to claim 1, characterized in that: A sliding opening (11) is provided on the surface of the pad (5), and the depth of the sliding opening (11) is consistent.

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