Heat dissipation pad and printed circuit board

Abstract

The utility model discloses a heat dissipation bonding pad and a printed circuit board, and relates to the field of vehicles. Wherein the heat dissipation bonding pad is square, the width of the heat dissipation bonding pad is a preset value, and the length of the heat dissipation bonding pad is a difference value between a preset length and the preset value. According to the utility model, the technical problem that the heat dissipation effect of the chip is poor is solved.

Description

Technical Field

[0001] This utility model relates to the field of vehicles, and more specifically, to a heat dissipation pad and a printed circuit board. Background Technology

[0002] With the rapid evolution of automotive electrification and intelligence, the integration level of automotive electronic components and PCBs (Printed Circuit Boards) is becoming increasingly higher. High-performance chips and high-density PCBs bring about huge power consumption and heat generation. Although existing heat dissipation pads have used heat conduction to transfer heat to the metal plane they are connected to, and further conduct the heat to the outside of the controller through the outer casing or external metal frame, they still cannot meet the heat dissipation requirements of some chips.

[0003] There is currently no effective solution to the above problems. Utility Model Content

[0004] This utility model provides a heat dissipation pad and a printed circuit board to at least solve the technical problem of poor heat dissipation of chips.

[0005] According to one aspect of the present invention, a heat dissipation pad is provided, comprising: the heat dissipation pad is square in shape, the width of the heat dissipation pad is a preset value, and the length of the heat dissipation pad is the difference between the preset length and the preset value.

[0006] Optionally, if the preset thermal pad shape stored in the device datasheet is square, the preset length is the length of any side of the preset thermal pad; if the preset thermal pad shape stored in the device datasheet is not square, the preset length is the length of the longest side of the preset thermal pad.

[0007] Optionally, the preset value is greater than or equal to 1 mm and less than the length of the shortest side of the preset thermal pad stored in the device datasheet. According to another aspect of this utility model embodiment, a printed circuit board is also provided, comprising: the printed circuit board having at least one of the above-described thermal pads, and a plurality of thermal vias, the plurality of thermal vias being uniformly disposed around the at least one thermal pad.

[0008] Optionally, if the length of the shortest side of a preset thermal pad stored in the device datasheet is greater than the preset length, a plurality of thermal pads are provided on the printed circuit board, wherein the number of thermal pads is equal to the length of the shortest side divided by the preset length and rounded down; if the length of the shortest board of the preset thermal pad is less than or equal to the preset length, a single thermal pad is provided on the printed circuit board.

[0009] Optionally, the orientation of the wide side of the thermal pad on the printed circuit board is consistent with the orientation of the shortest side of the preset thermal pad on the printed circuit board.

[0010] Optionally, when an even number of heat dissipation pads are provided on the printed circuit board, the centers of the multiple heat dissipation pads are on the same horizontal or vertical line as the center of the preset heat dissipation pad; when an odd number of heat dissipation pads are provided on the printed circuit board, the center of any one of the multiple heat dissipation pads is the same as the center of the preset heat dissipation pad, and the centers of the other heat dissipation pads, except for any one heat dissipation pad, are on the same horizontal or vertical line as the center of the preset heat dissipation pad; when a single heat dissipation pad is provided on the printed circuit board, the center of the heat dissipation pad is the same as the center of the preset heat dissipation pad.

[0011] Optionally, if multiple heat dissipation pads are provided on the printed circuit board, the center-to-center spacing between the multiple heat dissipation pads is 2-2.6 mm.

[0012] Optionally, the diameter of the heat dissipation via is 0.5-0.6 mm, the spacing between the centers of multiple heat dissipation vias is 1-1.2 mm, and the minimum spacing between the centers of multiple heat dissipation vias and the center of the heat dissipation pad is 1.05-1.3 mm.

[0013] Optionally, multiple heat dissipation vias are provided around at least two long sides of the heat dissipation pad.

[0014] Optionally, the area of ​​the pattern formed by the outer diameter edges of multiple heat dissipation vias is larger than the area of ​​the preset heat dissipation pads stored in the device datasheet.

[0015] In this embodiment of the invention, the heat dissipation pad is square in shape, with a preset width and a length equal to the difference between the preset length and the preset value. Designing the heat dissipation pad as square and its width as the preset value minimizes its area, ensuring device soldering quality while reserving space for heat dissipation vias. By designing the heat dissipation pad, it works in conjunction with preset heat dissipation pads stored in the device datasheet on the chip to improve heat dissipation, thereby solving the technical problem of poor chip heat dissipation. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of a heat dissipation pad according to an embodiment of the present utility model;

[0018] Figure 2 This is a flowchart of an optional heat dissipation pad design according to an embodiment of the present utility model;

[0019] Figure 3 This is a schematic diagram of an optional preset heat dissipation pad stored in a device manual according to an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a system, product, or device comprising a series of units is not necessarily limited to those explicitly listed, but may include other units not explicitly listed or inherent to such products or devices.

[0022] According to an embodiment of the present invention, a heat dissipation pad is provided. Figure 1 This is a schematic diagram of a heat dissipation pad according to an embodiment of the present utility model, as shown below. Figure 1As shown: The thermal pad 10 is square in shape. A preferred shape is a rounded square, but it is not limited to this; it can also be a right-angled square or a beveled square. The size of the thermal pad can be determined based on the thermal pad packaged on the chip. The width of the thermal pad is a preset value, which can be greater than or equal to 1 mm and less than the shortest side length of the thermal pad packaged on the chip. The length of the thermal pad can be the difference between a preset length and a preset value, where the preset length can be the longest side length of the thermal pad packaged on the chip. The size of the thermal pad packaged on the chip can be obtained by consulting the device datasheet; therefore, the thermal pad packaged on the chip is also the thermal pad in the device datasheet. The thermal pad is located on the printed circuit board 100, and there are multiple thermal vias 12 and device pins 11 around the thermal pad. The device pins are used to connect to the thermal pad.

[0023] The aforementioned thermal pads are pads used to dissipate heat from chips. A pad, in surface mount technology (SMT) for electronic components, is a metal sheet used to connect device leads to PCB traces. Its structural size and design directly affect the manufacturability of the printed circuit board, making it a crucial part of the electronic manufacturing process. Thermal pads can also be used in PCB packaging, which refers to graphically representing actual electronic components, such as chips, resistors, and capacitors, on a PCB to facilitate insertion or soldering.

[0024] The aforementioned preset values ​​are pre-set values, and their range can be greater than or equal to 1 mm, but less than the shortest side length of the thermal pad packaged on the chip. Example, the thermal pad packaged on the chip can be a square with a length and width of 2.7 mm. In this case, the shortest side length of the thermal pad packaged on the chip is 2.7 mm. A preferred preset value is 1 mm, but it is not limited to this; it can also be 1.5 mm, 1.7 mm, or other values ​​within the specified range depending on the actual application. It should be noted that the dimensions of the thermal pad packaged on the chip described above are only examples, and the dimensions of the thermal pad packaged on the chip in actual applications are not limited to these.

[0025] The preset length mentioned above is a pre-set length value, which can be the longest side length of the heat dissipation pad in the device datasheet, but is not limited to this. Other values ​​can be selected as the preset length according to the actual application.

[0026] In this embodiment of the invention, the heat dissipation pad is square in shape, with a preset width and a length equal to the difference between the preset length and the preset value. Designing the heat dissipation pad as square minimizes its area, ensuring device soldering quality while reserving space for heat dissipation vias. By designing the heat dissipation pad, it works in conjunction with preset heat dissipation pads stored in the device datasheet on the chip, thereby improving heat dissipation performance and solving the technical problem of poor chip heat dissipation.

[0027] Optionally, if the preset thermal pad shape stored in the device datasheet is square, the preset length is the length of any side of the preset thermal pad; if the preset thermal pad shape stored in the device datasheet is not square, the preset length is the length of the longest side of the preset thermal pad.

[0028] The aforementioned preset thermal pads are pre-set thermal pads, which are thermal pads packaged on the chip. The size and attribute information of the preset thermal pads can be obtained by consulting the device datasheet. Therefore, the preset thermal pads stored in the device datasheet are also the thermal pads packaged on the chip. The size information can be the length of each side of the preset thermal pad, and the attribute information can be the shape of the preset thermal pad.

[0029] The aforementioned device datasheet is a technical manual that stores preset thermal pad size and attribute information.

[0030] In one optional embodiment, the size and attribute information of a preset thermal pad can be obtained from a device datasheet, and the thermal pad can be designed based on this information. The preset length is the length of the longest side of the preset thermal pad. When the preset thermal pad is square, all sides of the preset thermal pad have the same length, so the preset length is the length of any one side of the preset thermal pad. When the preset thermal pad is not square, the preset length is the length of the longest side of the preset thermal pad. The preset length can be used to determine the length of the thermal pad, thus realizing the size design of the thermal pad.

[0031] According to an embodiment of the present invention, an embodiment of a printed circuit board is provided. For example... Figure 1 As shown, the printed circuit board 100 is provided with a heat dissipation pad 10 and multiple heat dissipation vias 12, with the multiple heat dissipation vias evenly distributed around the heat dissipation pad. By evenly placing multiple heat dissipation vias around the heat dissipation pad, the effective heat dissipation area exceeds the area of ​​the heat dissipation pad, thereby achieving more efficient heat dissipation for the chip.

[0032] The aforementioned printed circuit board, or PCB, is a support substrate for electronic components, used to connect electronic components in electronic devices. PCBs can be made of single-layer, double-layer, or multi-layer insulating materials, and thermal pads and vias can be provided on the PCB to dissipate heat from the electronic components on the PCB.

[0033] The aforementioned thermal vias are used to improve the heat dissipation efficiency of printed circuit boards (PCBs). They are typically not used for electrical connections but rather serve as a heat transfer path. In PCB design, the function of thermal vias is to help electronic components dissipate heat. The diameter of a thermal via is within a closed range of 0.5mm to 0.6mm. A preferred value is 0.6mm, but it is not limited to this; it can also be 0.53mm, 0.55mm, or other values ​​within this range depending on the specific application.

[0034] Optionally, if the length of the shortest side of a preset thermal pad stored in the device datasheet is greater than the preset length, a plurality of thermal pads are provided on the printed circuit board, wherein the number of thermal pads is equal to the length of the shortest side divided by the preset length and rounded down; if the length of the shortest board of the preset thermal pad is less than or equal to the preset length, a single thermal pad is provided on the printed circuit board.

[0035] The preset length mentioned above is a pre-set length value. A preferred preset length value is 3mm, but it is not limited to this. The preset length can also be 3.2mm or 2.8mm. Other values ​​can be selected as the preset length according to the actual application.

[0036] In one optional embodiment, the number of thermal pads on the printed circuit board can be determined based on the size of a preset thermal pad. When the size of the preset thermal pad stored in the device datasheet is large enough, multiple thermal pads need to be placed to ensure soldering quality. Taking a preset length of 3mm as an example, if the length of the shortest side of the preset thermal pad is greater than 3mm, it indicates that the size of the preset thermal pad is large, and multiple thermal pads need to be placed. The number of thermal pads is equal to the length of the shortest side divided by the preset length and rounded down. If the length of the shortest side of the preset thermal pad is less than 3mm, it indicates that the size of the preset thermal pad is small, and multiple thermal pads are not needed; one thermal pad is sufficient on the printed circuit board.

[0037] Optionally, the orientation of the wide side of the thermal pad on the printed circuit board is consistent with the orientation of the shortest side of the preset thermal pad on the printed circuit board.

[0038] The aforementioned preset direction is a pre-set direction, which is the direction of the shortest side of the preset heat dissipation pad on the printed circuit board.

[0039] The wider side of the aforementioned heat dissipation pad is the shorter side of a square heat dissipation pad.

[0040] Optionally, when an even number of heat dissipation pads are provided on the printed circuit board, the centers of the multiple heat dissipation pads are on the same horizontal or vertical line as the center of the preset heat dissipation pad; when an odd number of heat dissipation pads are provided on the printed circuit board, the center of any one of the multiple heat dissipation pads is the same as the center of the preset heat dissipation pad, and the centers of the other heat dissipation pads, except for any one heat dissipation pad, are on the same horizontal or vertical line as the center of the preset heat dissipation pad; when a single heat dissipation pad is provided on the printed circuit board, the center of the heat dissipation pad is the same as the center of the preset heat dissipation pad.

[0041] In one optional embodiment, when there is only one thermal pad on the printed circuit board, the center of the thermal pad is placed at a position corresponding to the center of a preset thermal pad, and thermal vias are provided around the thermal pad. When there are multiple thermal pads on the printed circuit board, the position corresponding to the center of the preset thermal pad is taken as the origin, the width of the thermal pad is taken as the y-axis, and the vertical direction of the width of the thermal pad is taken as the x-axis. When there is an even number of thermal pads on the printed circuit board, the centers of the multiple thermal pads are on the same horizontal or vertical line as the center of the preset thermal pad. When there is an odd number of thermal pads on the printed circuit board, the center of any one thermal pad is the same as the center of the preset thermal pad, and the centers of the other thermal pads are on the same horizontal or vertical line as the center of the preset thermal pad. This makes the pattern formed by the thermal pads an axisymmetric pattern with the x-axis as the axis of symmetry.

[0042] Optionally, if multiple heat dissipation pads are provided on the printed circuit board, the center-to-center spacing between the multiple heat dissipation pads is 2-2.6 mm.

[0043] The spacing between the centers of the aforementioned heat dissipation pads refers to the distance between the centers of two adjacent heat dissipation pads. It can be 2.1mm, 2.3mm, or 2.5mm, but is not limited to these values. Other values ​​that meet the range of values ​​can be selected as the spacing between the centers of multiple heat dissipation pads according to the actual application.

[0044] Optionally, the diameter of the heat dissipation via is 0.5-0.6 mm, the spacing between the centers of multiple heat dissipation vias is 1-1.2 mm, and the minimum spacing between the centers of multiple heat dissipation vias and the center of the heat dissipation pad is 1.05-1.3 mm.

[0045] The spacing between the centers of the aforementioned heat dissipation vias refers to the distance between the centers of two adjacent heat dissipation vias. It can be 1.05mm or 1.1mm, but is not limited to these values. Other values ​​within the specified range can be selected as the spacing between the centers of multiple heat dissipation vias, depending on the actual application. The minimum spacing between the centers of multiple heat dissipation vias and the centers of the heat dissipation pads can be 1.1mm or 1.2mm, but is not limited to these values. The minimum spacing between the centers of multiple heat dissipation vias and the centers of the heat dissipation pads simply needs to meet the specified range.

[0046] Optionally, multiple heat dissipation vias are provided around at least two long sides of the heat dissipation pad.

[0047] In one alternative embodiment, it is necessary to ensure that there are heat dissipation vias near at least two of the longer sides of the heat dissipation pad. If there is enough space, heat dissipation vias should be placed near all four sides of the heat dissipation pad to achieve sufficient heat dissipation.

[0048] Optionally, the area of ​​the pattern formed by the outer diameter edges of multiple heat dissipation vias is larger than the area of ​​the preset heat dissipation pads stored in the device datasheet.

[0049] In one optional embodiment, the area of ​​the pattern formed by the outer diameter edges of the outermost plurality of heat dissipation vias must be greater than the area of ​​the preset heat dissipation pads in the device datasheet. By making the area of ​​the pattern formed by the outer diameter edges of the outermost plurality of heat dissipation vias greater than the area of ​​the preset heat dissipation pads in the device datasheet, the heat dissipation area can be increased, thereby improving the overall heat dissipation efficiency. In addition, a larger heat dissipation area helps to distribute heat more evenly, reduce the generation of local hot spots, and help prevent device overheating and extend device life.

[0050] The following description uses a preferred embodiment. Figure 2 This is an optional heat dissipation pad design flowchart according to an embodiment of the present utility model, such as... Figure 2 As shown, after the process begins, it first checks whether the thermal pad in the component datasheet, i.e., the preset pad, is square. If so, a thermal pad with a width of 1mm and a length of (L-1)mm is designed based on the length L of any side of the thermal pad in the component datasheet. If not, a thermal pad with a length of (L-1)mm and a width of 1mm is drawn based on the length L and width W of the thermal pad in the component datasheet. Here, 1mm is the preset value mentioned above. Then, it checks whether L is greater than 3mm and whether W is greater than 3mm. If L is not greater than 3mm, one thermal pad is placed; otherwise, multiple thermal pads are placed, with the number of thermal pads being the value of L divided by 3mm. If W is not greater than 3mm, one thermal pad is placed; otherwise, multiple thermal pads are placed, with the number of thermal pads being the value of W divided by 3mm.

[0051] Next, determine if the number of thermal pads is even. If the thermal pads are square in the device datasheet, and the number of thermal pads is even, ensure that the center of each thermal pad is on the same horizontal or vertical line as the center of the thermal pad in the device datasheet. If the number of thermal pads is not even, place one thermal pad at the position corresponding to the center of the thermal pad in the device datasheet, and ensure that the centers of the remaining pads are on the same horizontal or vertical line as the center of the thermal pad. It should be noted that regardless of whether the number of thermal pads is even or not, they should be placed symmetrically with a center-to-center spacing of 2mm-2.6mm between all thermal pads.

[0052] When determining whether the number of thermal pads is even, if the number of thermal pads is not even and the thermal pads in the datasheet are not square, the placement direction of the thermal pads should be such that one side with a width of (L-1) mm is aligned with the long side of the thermal pad in the datasheet, ensuring that the center of the thermal pad is on the same horizontal or vertical line as the center of the thermal pad in the datasheet. If the number of thermal pads is not even, the placement direction of the thermal pads should be such that one side with a width of (L-1) mm is aligned with the long side of the thermal pad in the datasheet, placing one thermal pad in the center of the thermal pad in the datasheet, and ensuring that the centers of the remaining thermal pads are on the same horizontal or vertical line as the center of the thermal pad in the datasheet. It should be noted that regardless of whether the number of thermal pads is even or not, they should be placed symmetrically according to the rule of a center-to-center distance of 2 mm-2.6 mm between all thermal pads.

[0053] Next, set the size of the heat dissipation vias to a diameter of 0.6mm, and follow the rule that the center-to-center spacing between vias is 1mm-1.2mm, and the center-to-center spacing between vias and heat dissipation pads is 1.05mm-1.3mm. Distribute the heat dissipation vias evenly around the heat dissipation pads. After completing the heat dissipation pad design, ensure that the area of ​​the shape formed by the outermost ring of vias is larger than the area of ​​the heat dissipation pad specified in the manual.

[0054] Figure 3 This is a schematic diagram of an optional preset thermal pad stored in a device datasheet according to an embodiment of the present invention. Figure 3 As shown, the preset thermal pad 30 stored in the device datasheet can be square or rectangular with different lengths and widths. The preset thermal pad stored in the device datasheet is located on the chip 300. There are multiple device pins 31 around the preset thermal pad stored in the device datasheet. The device pins are used to connect to the preset thermal pad stored in the device datasheet.

[0055] In a preferred embodiment, the preset thermal pad stored in the device datasheet is a square with a length and width of 2.7 mm. Based on the size of the preset thermal pad, the thermal pad is designed as a rectangle with a width of 1 mm and a length of 2.6 mm. The preset length is set to 3 mm. Since the shortest section of the preset thermal pad is less than 3 mm, a single thermal pad is provided and placed at the center of the preset thermal pad. The thermal vias have a diameter of 0.6 mm and a spacing of 1.1 mm. Due to device size limitations, the center-to-center distance between the thermal vias and the thermal pad is set to 1.07 mm. After the design is completed, the area of ​​the shape formed by the outermost edge of the thermal vias is 7.672 mm². 2 The default area of ​​the thermal pad is 7.29 mm². 2 The area of ​​the pattern formed by the outer diameter edge of the heat dissipation via is greater than the area of ​​the preset heat dissipation pad stored in the device datasheet.

[0056] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A heat dissipation pad, characterized in that, The heat dissipation pad is square in shape, the width of the heat dissipation pad is a preset value, and the length of the heat dissipation pad is the difference between the preset length and the preset value; if the preset shape of the heat dissipation pad stored in the device datasheet is square, the preset length is the length of any side of the preset heat dissipation pad. If the shape of the preset thermal pad stored in the device manual is not square, the preset length is the length of the longest side of the preset thermal pad.

2. The heat dissipation pad according to claim 1, characterized in that, The preset value is greater than or equal to 1 mm and less than the length of the shortest side of the preset heat dissipation pad stored in the device manual.

3. A printed circuit board, characterized in that, The printed circuit board is provided with at least one heat dissipation pad as described in any one of claims 1 to 2, and a plurality of heat dissipation vias, wherein the plurality of heat dissipation vias are uniformly disposed around at least one heat dissipation pad.

4. The printed circuit board according to claim 3, characterized in that, When the length of the shortest side of a preset thermal pad stored in the device datasheet is greater than a preset length, a plurality of such thermal pads are provided on the printed circuit board, wherein the number of such thermal pads is equal to the length of the shortest side divided by the preset length and rounded down; when the length of the shortest side of a preset thermal pad is less than or equal to the preset length, a single such thermal pad is provided on the printed circuit board.

5. The printed circuit board according to claim 4, characterized in that, The orientation of the wide side of the heat dissipation pad on the printed circuit board is consistent with the orientation of the shortest side of the preset heat dissipation pad on the printed circuit board.

6. The printed circuit board according to claim 4, characterized in that, When an even number of thermal pads are provided on the printed circuit board, the centers of the multiple thermal pads are on the same horizontal or vertical line as the center of the preset thermal pad; when an odd number of thermal pads are provided on the printed circuit board, the center of any one of the multiple thermal pads is the same as the center of the preset thermal pad, and the centers of the other thermal pads, excluding any one of the multiple thermal pads, are on the same horizontal or vertical line as the center of the preset thermal pad; when a single thermal pad is provided on the printed circuit board, the center of the thermal pad is the same as the center of the preset thermal pad.

7. The printed circuit board according to claim 3, characterized in that, When multiple heat dissipation pads are provided on the printed circuit board, the center-to-center spacing between the multiple heat dissipation pads is 2-2.6 mm.

8. The printed circuit board according to claim 3, characterized in that, The diameter of the heat dissipation via is 0.5-0.6 mm, and the distance between the centers of the plurality of heat dissipation vias is 1-1.2 mm. The minimum distance between the center of the plurality of heat dissipation vias and the center of the heat dissipation pad is 1.05-1.3 mm.

9. The printed circuit board according to claim 3, characterized in that, The plurality of heat dissipation vias are provided around at least two long sides of the heat dissipation pad.

10. The printed circuit board according to claim 3, characterized in that, The area of ​​the pattern formed by the outer diameter edges of the multiple heat dissipation vias is greater than the area of ​​the preset heat dissipation pad stored in the device datasheet.

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