Circuit board for vehicle-mounted module and vehicle-mounted module

Abstract

The present invention relates to a circuit board for an on-board module and an on-board module. The circuit board comprises: a board body (11), a photosensitive chip (12) arranged on the board body (11); the board body (11) comprises at least one hard base layer (111) and at least one flexible base layer (112); a through hole (11a) penetrating the board body is provided at the position where the photosensitive chip (12) is provided; and a heat dissipation element (11b) is embedded in the through hole (11a). In this solution, the insulating surface of the photosensitive chip is in direct contact with the heat dissipation element, resulting in an excellent heat dissipation effect and avoiding heat accumulation between the chip and the circuit board. At the same time, the heat dissipation element can also fill the traditional vias (i.e., via holes) on the circuit board, thereby ensuring the flatness of the entire circuit board.

Description

Technical Field

[0001] The present invention relates to the field of camera modules, and in particular to a circuit board for a vehicle-mounted module and a vehicle-mounted module. Background Art

[0002] With the advancement of technology, image acquisition devices are widely used in various fields, especially in automotive technology. With the increasing popularity of autonomous and assisted driving applications, the performance requirements for automotive modules are becoming increasingly stringent. For example, automotive modules operate for long periods of time, generating significant internal heat. For modules made of different circuit board materials (such as FR4, BT, and polyimide), the significant differences in thermal expansion coefficients can lead to image quality issues such as excessive temperature drift, which can seriously affect the module's resolution. Summary of the Invention

[0003] The object of the present invention is to provide a circuit board and a vehicle-mounted module for a vehicle-mounted module, so as to solve the problem of poor heat dissipation capability of the module.

[0004] To achieve the above-mentioned object of the invention, the present invention provides a circuit board for a vehicle-mounted module, comprising: a board body, a photosensitive chip arranged on the board body;

[0005] The plate body comprises at least one hard base layer and at least one flexible base layer;

[0006] The position where the photosensitive chip is arranged on the plate is provided with a through hole penetrating the plate body;

[0007] A heat dissipation element is embedded in the through hole.

[0008] According to one aspect of the present invention, one end of the heat dissipation element contacts an insulating position on the surface of the photosensitive chip.

[0009] According to one aspect of the present invention, a receiving groove for receiving the photosensitive chip is provided on the plate.

[0010] According to one aspect of the present invention, the receiving groove is provided on a hard base layer included in the plate body;

[0011] The depth of the receiving groove is the same as the thickness of the hard base layer in which it is located.

[0012] According to one aspect of the present invention, the plate body is provided with multiple layers of the flexible base layer, and the flexible base layers are stacked;

[0013] The receiving groove is provided on a hard base layer included in the plate body and a flexible base layer connected to the hard base layer;

[0014] The depth of the receiving groove is the same as the total thickness of the hard base layer and the flexible base layer in which the receiving groove is located.

[0015] According to one aspect of the present invention, the hard base layer has two layers;

[0016] The flexible base layer is arranged between two layers of the hard base layers.

[0017] According to one aspect of the present invention, the heat dissipation element is a metal column.

[0018] To achieve the above-mentioned object of the invention, the present invention provides a vehicle-mounted module using the aforementioned circuit board, comprising: a circuit board, and an optical lens arranged on the circuit board;

[0019] The optical lens is arranged on a side of the circuit board where the photosensitive chip is installed, and is opposite to the photosensitive chip.

[0020] According to one embodiment of the present invention, by adding a groove design and embedding a heat dissipation element in a rigid-flexible circuit board, the present invention offers an assembly method different from that of traditional grooved circuit boards. The addition of a flexible portion eliminates the need for separate flexible board ACF press-fit installation during assembly, further reducing the number of module manufacturing steps and increasing assembly flexibility. This also provides greater potential for development in the field of thin-profile packaging, particularly in the automotive sector. This solution meets the stringent resolution and reliability requirements of high-pixel ADAS camera modules, providing further potential for development in the automotive sector.

[0021] According to one solution of the present invention, the insulating surface of the photosensitive chip is in direct contact with the heat dissipation element, which has an excellent heat dissipation effect and avoids the enrichment of heat between the chip and the circuit board. At the same time, the heat dissipation element can also fill the traditional via holes (i.e., via holes) on the circuit board, which is beneficial to ensure the flatness of the entire circuit board.

[0022] According to one solution of the present invention, a receiving groove is designed at the chip placement location on the circuit board. The length, width, and height of the groove are rationally designed based on chip size, bonding height, and cleaning yield. This helps reduce the overall module height and saves assembly space. Furthermore, by embedding a heat sink within the groove, the groove can effectively prevent glue overflow and circuit board deformation.

[0023] According to one solution of the present invention, the large-diameter ends of the intermediate heat-conducting pillars effectively ensure the contact area between the intermediate heat-conducting pillars and the photosensitive chip, thereby ensuring efficient heat dissipation. Furthermore, the provision of thermal insulation sleeves on the intermediate heat-conducting pillars effectively prevents the transferred heat from being dissipated onto the circuit board, thereby suppressing thermal deformation of the circuit board and, in turn, thermal drift of the photosensitive chip, effectively ensuring the imaging quality and service life of the photosensitive chip.

[0024] According to one solution of the present invention, by adopting a circuit board structure that combines soft and hard, and using a soft layer as the bottom surface of the groove for installing the photosensitive chip, it is ensured that when the photosensitive chip undergoes slight deformation due to temperature, the flexible base layer can adapt to the change, which is beneficial to ensuring the service life of the entire photosensitive chip.

[0025] According to one solution of the present invention, a circuit board with a multi-layer structure ensures that the entire board has excellent mechanical properties. Especially when applied to a vehicle-mounted module, its good mechanical properties can not only ensure the imaging performance of the entire module under different environments, but also ensure the long service life of the entire vehicle-mounted module. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematically showing a front view of a circuit board according to one embodiment of the present invention;

[0027] Figure 2 Schematically showing a bottom view of a circuit board according to one embodiment of the present invention;

[0028] Figure 3 A schematic diagram showing the structure of a vehicle-mounted module according to an embodiment of the present invention;

[0029] Figure 4 A schematic diagram showing the structure of a heat dissipation element according to an embodiment of the present invention;

[0030] Figure 5 A structural diagram schematically showing a heat dissipation element according to another embodiment of the present invention;

[0031] Figure 6 A structural diagram schematically showing a heat dissipation element according to another embodiment of the present invention;

[0032] Figure 7 A schematic diagram showing the structure of a traditional vehicle-mounted module;

[0033] Figure 8 The figure schematically shows the structure of an on-vehicle module using a circuit board according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0035] When describing the embodiments of the present invention, the orientation or positional relationship expressed by the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or positional relationship shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0036] like Figure 1 As shown, according to one embodiment of the present invention, a circuit board for a vehicle-mounted module of the present invention includes: a board body 11, and a photosensitive chip 12 arranged on the board body 11. In this embodiment, the board body 11 is a multi-layer structure, which includes at least one hard base layer 111 and at least one flexible base layer 112. In this embodiment, the hard base layer 111 adopts a printed circuit board, and the flexible base layer 112 adopts a flexible substrate. In this embodiment, a through hole 11a that passes through the board body 11 is correspondingly provided at the position where the photosensitive chip 12 is provided on the board body 11. A heat dissipation element 11b is embedded in the through hole 11a. In this embodiment, these through holes 11a can be through holes (i.e., Via holes) provided on the circuit board, or they can be additional through holes. If they are through holes, they can be used as conductive parts through the heat dissipation element, or they can be conductive in other ways, and the heat dissipation element is only embedded therein.

[0037] According to the present invention, the use of a multi-layer circuit board ensures that the entire board has excellent mechanical properties. Especially when applied to a vehicle-mounted module, its good mechanical properties can not only ensure the imaging performance of the entire module under different environments, but also ensure the long service life of the entire vehicle-mounted module.

[0038] like Figure 1 As shown, according to one embodiment of the present invention, one end of the heat dissipation element 11b contacts the insulating portion of the photosensitive chip 12. This arrangement effectively ensures that the heat dissipation element 11b can promptly conduct away the heat generated by the photosensitive chip, ensuring that the temperature variations between the surface of the photosensitive chip and the surface of the circuit board where the photosensitive chip is mounted are small and balanced. This, in turn, helps suppress deformation of the chip, effectively preventing temperature drift of the photosensitive chip caused by heat accumulation or variation, and is beneficial for improving imaging quality.

[0039] like Figure 1 As shown, according to one embodiment of the present invention, a receiving groove 11c for receiving a photosensitive chip 12 is provided on the board body 11. In this embodiment, the chip is glued into the receiving groove 11c of the circuit board with glue.

[0040] like Figure 1 As shown, according to one embodiment of the present invention, the receiving groove 11c is provided on a hard base layer 111 included in the plate body 11. In this embodiment, the depth of the receiving groove 11c is the same as the thickness of the hard base layer 111 in which it is located. Through this arrangement, the hard base layer 111 is penetrated, and the bottom of the receiving groove 11c is the flexible base layer 112. This arrangement ensures that when the photosensitive chip undergoes slight deformation due to temperature, the flexible base layer 112 can adapt to the deformation, which is beneficial to ensuring the service life of the entire photosensitive chip.

[0041] In this embodiment, the length, width and height of the receiving groove are reasonably designed based on the length and width dimensions of the chip, the accuracy of bonding the chip, the COB wire height, the height of the connecting wire arc, and whether the groove depth affects the cleaning yield.

[0042] like Figure 1 As shown, according to another embodiment of the present invention, a plurality of layers of flexible base layers 112 are provided in the board body 11, and the flexible base layers 112 are stacked. In this embodiment, two layers of flexible base layers 112 are provided on the board body 11. The receiving groove 11c is provided on a layer of hard base layer 111 contained in the board body 11 and a flexible base layer 112 connected to the hard base layer 111. The depth of the receiving groove 11c is the same as the total thickness of the hard base layer 111 and the flexible base layer 112 in which it is located. Through this arrangement, when the hard base layer 111 is penetrated, the first layer of the flexible base layer 112 is also penetrated, and the bottom of the receiving groove 11c and the side position adjacent to the bottom are both flexible base layers 112. Through the above arrangement, it is ensured that when the photosensitive chip undergoes slight deformation due to the influence of temperature, the flexible base layer 112 can adapt to the change, which is beneficial to ensuring the service life of the entire photosensitive chip.

[0043] like Figure 1 As shown, according to one embodiment of the present invention, the hard base layer 111 has two layers; the flexible base layer 112 is disposed between the two layers of the hard base layer 111 .

[0044] like Figure 1 and Figure 4 As shown, according to one embodiment of the present invention, the heat dissipation element 11b is a metal column. In this embodiment, the heat dissipation element 11b is a columnar body with a constant diameter, which is made of metal copper.

[0045] like Figure 5 According to another embodiment of the present invention, heat dissipation element 11b includes: an intermediate heat-conducting column 11b1 and a heat-insulating sleeve 11b2 coaxially disposed with intermediate heat-conducting column 11b1. In this embodiment, intermediate heat-conducting column 11b1 is a metal column (e.g., copper), and the thermal conductivity of the heat-insulating sleeve 11b2 is lower than that of the intermediate heat-conducting column 11b1.

[0046] According to another embodiment of the present invention, the two opposite ends of the intermediate heat-conducting column 11b1 are radially extended to form large-diameter ends. In this embodiment, the heat-insulating sleeve 11b2 is provided with an end receiving groove 11b21 (see FIG. 1 ) for receiving the large-diameter end of the intermediate heat-conducting column 11b1. Figure 6 ), or, the length of the heat-insulating sleeve 11b2 is less than the length of the middle heat-conducting column 11b1, and the heat-insulating sleeve 11b2 is located between the two large diameter ends (see Figure 5 ).

[0047] The aforementioned arrangement, with both ends of the intermediate heat-conducting column configured as large-diameter ends, effectively ensures the contact area between the intermediate heat-conducting column and the photosensitive chip, thereby ensuring efficient heat dissipation. Furthermore, the provision of a thermal insulation sleeve on the intermediate heat-conducting column effectively prevents the transferred heat from being dissipated onto the circuit board, thereby suppressing thermal deformation of the circuit board and, in turn, thermal drift of the photosensitive chip, effectively ensuring the imaging quality and service life of the photosensitive chip.

[0048] like Figure 3 As shown, according to one embodiment of the present invention, an in-vehicle module using the aforementioned circuit board includes: a circuit board 1, and an optical lens 2 disposed on the circuit board 1. In this embodiment, the optical lens 2 is disposed on the side of the circuit board 1 where the photosensitive chip 12 is mounted, and is opposite to the photosensitive chip 12.

[0049] According to the present invention, since a heat dissipation element for the photosensitive chip is provided on the circuit board, the accumulation of heat between the optical lens and the circuit board can be effectively suppressed, so that the interior of the optical lens is less affected, which is further beneficial to ensuring the imaging quality of the entire module.

[0050] In order to further illustrate the advantages of the present invention in the thickness direction, further description will be given with reference to the accompanying drawings.

[0051] See also Figure 7 As shown, the circuit board used in the traditional vehicle-mounted module is a conventional structure of the prior art, and the overall thickness after assembly reaches 4.15±0.2mm; see Figure 8As shown, the vehicle-mounted module of the present application adopts the aforementioned circuit board of the present invention, and the overall thickness after assembly reaches 4±0.2mm. It can be seen that the thickness of the circuit board of the present invention is significantly reduced compared to the thickness of the traditional vehicle-mounted module, making it smaller and more convenient and flexible to install.

[0052] The above contents are merely examples of specific solutions of the present invention. For devices and structures not described in detail, it should be understood that they can be implemented by adopting general devices and methods available in the art.

[0053] The above description is merely one embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A circuit board for a vehicle-mounted module, characterized in that: include: A plate body (11), and a photosensitive chip (12) disposed on the plate body (11); The plate body (11) comprises at least one hard base layer (111) and at least one flexible base layer (112); The plate body (11) is provided with a through hole (11a) penetrating the plate body at a position where the photosensitive chip (12) is provided; A heat dissipation element (11b) is embedded in the through hole (11a), and the heat dissipation element (11b) comprises: an intermediate heat-conducting column (11b1) and a heat-insulating sleeve (11b2) coaxially arranged with the intermediate heat-conducting column (11b1); the heat-insulating sleeve (11b2) is made of a material with a lower thermal conductivity than that of the intermediate heat-conducting column (11b1); and opposite ends of the intermediate heat-conducting column (11b1) extend radially to form large-diameter ends. The plate body (11) is provided with a receiving groove (11c) for receiving the photosensitive chip (12); One end of the heat dissipation element (11b) contacts an insulating position on the surface of the photosensitive chip (12); The plate body (11) is provided with multiple layers of the flexible base layer (112), and the flexible base layers (112) are stacked. The hard base layer (111) is penetrated by the through hole (11a), and the first layer of the flexible base layer (112) is also penetrated by the through hole (11a). The bottom of the accommodating groove (11c) and the side positions adjacent to the bottom are both flexible base layers (112). The accommodating groove (11c) is provided on a hard base layer (111) included in the plate body (11) and a flexible base layer (112) connected to the hard base layer (111); The depth of the accommodating groove (11c) is the same as the total thickness of the hard base layer (111) and the flexible base layer (112) in which it is located.

2. The circuit board according to claim 1, wherein: The hard base layer (111) has two layers; The flexible base layer (112) is arranged between two layers of the hard base layers (111).

3. The circuit board according to claim 2, characterized in that The heat dissipation element (11b) is a metal column.

4. A vehicle-mounted module using the circuit board according to any one of claims 1 to 3, characterized in that: include: A circuit board (1), and an optical lens (2) arranged on the circuit board (1); The optical lens (2) is arranged on a side of the circuit board (1) where the photosensitive chip (12) is mounted, and is opposite to the photosensitive chip (12).

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