An autonomous driving perception system vehicle-mounted printed circuit board and a processing method thereof

Abstract

The application discloses an automatic driving perception system vehicle-mounted printed circuit board and a processing method thereof. The printed circuit board body comprises a plurality of layers of alternating dielectric and conductor layers, signal lines are arranged on the conductor layers, the signal lines are connected with blind holes through copper sinking structures, and an insulating ring is formed around the blind holes, so that the signal path realizes accurate conduction and maintains electrical isolation in a high-density wiring area, effectively stabilizes local impedance, reduces parasitic coupling and signal reflection in the transmission process of high-speed signals in a multilayer structure, and thus guarantees the integrity and reliability of high-frequency signals. The printed circuit board body forms a ground plane and is connected with the blind holes through vias, so that the ground path is continuous and uniformly distributed, and the electrical shielding effect is enhanced. The cooperation of the blind hole copper sinking structure and the ground via simultaneously provides reliable support for multilayer high-density wiring, so that the printed circuit board ensures stable signal transmission and long-term reliability of the structure in a complex vehicle-mounted environment.

Description

Technical Field

[0001] This invention relates to the field of circuit board technology, and more specifically, to an in-vehicle printed circuit board for an autonomous driving perception system and its processing method. Background Technology

[0002] With the rapid development of autonomous driving technology, the performance requirements of vehicle perception systems are increasing. Millimeter-wave radar, high-speed communication modules, and other high-frequency sensors need to achieve high-speed, low-distortion, and high-precision signal transmission in the vehicle environment. To meet these requirements, automotive printed circuit boards (PCBs) are increasingly adopting multi-layer, high-density wiring and compact stacking in their structural design, while also ensuring mechanical reliability and long-term stability. Especially in high-frequency signal applications, PCB materials, electrical characteristics, conductor wiring accuracy, and interlayer alignment are extremely sensitive to signal integrity. In addition, the vehicle operating environment is complex and variable, including drastic temperature changes, humidity fluctuations, and long-term vibration loads, which places higher demands on the electrical and mechanical performance of PCBs. Therefore, maintaining signal transmission stability and PCB structural reliability in complex environments while ensuring high-density interconnection and multi-layer wiring has become a key technical issue of concern to the industry.

[0003] In existing technologies, multilayer automotive printed circuit boards typically use vias or through-holes to achieve interlayer connectivity. When PCB wiring density increases, the number of conductor layers stacked increases, or signal paths become more complex and interwoven, slight geometric deviations in the spatial layout of vias and surrounding conductor layers can occur in high-density signal wiring areas. This can lead to local impedance inhomogeneity and parasitic coupling, causing signal reflection or crosstalk. Simultaneously, when multiple vias or through-holes are adjacent to wiring areas, uneven distribution of local electrical and mechanical stress can also affect signal transmission stability. These local structural problems are particularly pronounced near high-speed signal paths, becoming a major factor limiting the quality of high-frequency signal transmission and PCB reliability.

[0004] Therefore, there is a need to provide an on-board printed circuit board for an autonomous driving perception system and its processing method to solve the problems of uneven local impedance and limited signal transmission stability in the high-density wiring areas of existing circuit boards. Summary of the Invention

[0005] The main objective of this invention is to provide an on-board printed circuit board for an autonomous driving perception system and its processing method, aiming to solve the technical problems mentioned in the background art.

[0006] The present invention adopts the following technical solution: An in-vehicle printed circuit board for an autonomous driving perception system includes a circuit board body, the circuit board body comprising several layers of alternating dielectric and conductor layers, the circuit board body having blind vias along the conductor layers, the blind vias penetrating at least a portion of the dielectric layers along the axial direction, and the blind vias having a copper plating structure. Signal lines are provided on the conductor layer, and the signal lines are connected to blind vias through a copper plating structure. An insulating ring is formed between the blind vias and the signal lines. The circuit board body forms a ground plane on a conductor layer away from the signal lines, and the ground plane is connected to blind vias through vias.

[0007] Furthermore, the signal line is spaced with an intermediate medium between it and an adjacent signal line. The thickness of the intermediate medium and the thickness of the superimposed intermediate medium are both 50 μm. The width of the signal line is 50 μm. The diameter of the blind via is less than or equal to 0.1 mm. The connection end between the signal line and the blind via is thickened with copper plating to form a pad.

[0008] Furthermore, an annular or rectangular copper plating reinforcement is formed on the outer periphery of the blind via along the horizontal direction. A preset gap is provided between the copper plating reinforcement and the blind via and the signal line. The preset gap is covered with solder resist ink.

[0009] Furthermore, each conductor layer in the circuit board body is provided with an alignment hole, and the axis of the alignment hole is perpendicular to the plane where the conductor layer is located; The conductor layers are stacked and positioned with alignment holes, and the interlayer alignment of the conductor layers is ±0.05mm.

[0010] Furthermore, a grounding wire is also provided on the conductor layer. The grounding wire is arranged parallel to the signal wire and extends along the first direction. The width of the grounding wire is 50μm.

[0011] Furthermore, the circuit board body is provided with a plurality of blind vias, which are arranged in an array along the second direction, and the ground wire is distributed between the two signal lines; The insulating ring is a hollow structure formed in the dielectric layer. The inner diameter of the insulating ring is larger than the diameter of the blind hole. The impedance control of the signal line is maintained within ±8% tolerance by controlling the dielectric thickness and line width.

[0012] Furthermore, the vias are distributed along the axial direction of the blind hole on the outer periphery of the blind hole. When there are multiple vias, the multiple vias are arranged in a circular array around the blind hole.

[0013] A method for processing an on-board printed circuit board for an autonomous driving perception system, used to process the on-board printed circuit board for an autonomous driving perception system as described in any of the preceding claims, comprising: A laminated circuit board body is provided, the circuit board body comprising several layers of alternately stacked dielectric and conductor layers; Drill holes on opposite ends of the circuit board body to form connected blind holes and through holes, and then deposit copper on the blind holes to form a copper deposit structure. Signal lines connected to the copper plating structure are etched on the conductor layer. An insulating ring is formed around the connection between the blind via and the signal line on the conductor layer, with the blind via as the rotation center.

[0014] Furthermore, during the process of etching signal lines connected to the copper plating structure on the conductor layer, a pre-defined signal line pattern is transferred to the surface of the conductor layer using a micro-laser or optical exposure method, while multi-point heating is performed to ensure uniform thermal expansion of the dielectric and conductor layers.

[0015] Furthermore, after the step of forming an insulating ring around the connection between the blind via and the signal line on the conductor layer, the method further includes: Solder resist ink is applied to the surface of the conductor layer and the copper plating structure. Directional hot air is used to cure the solder resist ink along the connection area between the blind via and the signal line, wherein the solder resist ink does not enter the insulating ring area during the coating process.

[0016] Beneficial effects: In this invention, signal lines are placed on the conductor layers of a circuit board body comprising several alternating layers of dielectric and conductor layers. These signal lines are connected to blind vias via a copper plating structure, and an insulating ring is formed around the blind vias. This ensures precise conduction and electrical isolation of the signal path in high-density wiring areas, effectively stabilizing local impedance. This reduces parasitic coupling and signal reflection during high-speed signal transmission in multi-layer structures, thereby guaranteeing the integrity and reliability of high-frequency signals. Furthermore, a ground plane is formed on the conductor layer away from the signal lines on the circuit board body and connected to the blind vias via vias, ensuring a continuous and uniform ground path distribution. This enhances electrical shielding and improves mechanical strength. The combination of the copper plating structure and the ground vias provides reliable support for multi-layer high-density wiring, enabling the circuit board to withstand vibration, temperature, and humidity changes in complex automotive environments, ensuring stable signal transmission and long-term structural reliability. Attached Figure Description

[0017] Fig. 1 This is a partial structural diagram of the vehicle-mounted printed circuit board of the autonomous driving perception system of the present invention; Fig. 2 This is a schematic diagram of the second partial structure of the vehicle-mounted printed circuit board of the autonomous driving perception system of the present invention; Fig. 3 This is a schematic diagram of the third partial structure of the vehicle-mounted printed circuit board of the autonomous driving perception system of the present invention; in: 1. Circuit board body; 11. Dielectric; 12. Conductor layer; 13. Blind via; 14. Insulating ring; 15. Ground plane; 16. Via; 17. Alignment hole; 2. Plating copper structure; 3. Signal line; 4. Solder pad; 5. Plating copper reinforcement; 6. Solder resist ink; 7. Ground wire; The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] Reference Figs. 1 to 3 The present invention proposes an in-vehicle printed circuit board for an autonomous driving perception system, comprising: a circuit board body 1, the circuit board body 1 comprising several layers of alternately stacked dielectric 11 and conductor 12, the circuit board body 1 having blind vias 13 along the conductor 12, the blind vias 13 penetrating at least a portion of the dielectric 11 layer along the axial direction, and the blind vias 13 having a copper plating structure 2 formed by copper plating. A signal line 3 is provided on the conductor layer 12. The signal line 3 is connected to the blind via 13 through the copper plating structure 2. An insulating ring 14 is formed between the blind via 13 and the signal line 3. The circuit board body 1 forms a ground plane 15 on the conductor layer 12 away from the signal line 3, and the ground plane 15 is connected to the blind via 13 through the via 16.

[0023] In the above embodiments, the on-board printed circuit board of the autonomous driving perception system includes a circuit board body 1. The circuit board body 1 consists of multiple layers of alternatingly stacked dielectric 11 and conductor layers 12. The dielectric 11 is made of epoxy resin or polyimide-based composite material, and its thickness can be selected according to the frequency and wiring density of the high-speed signal. The conductor layer 12 is made of copper foil, and impedance matching of different signal lines 3 or power lines can be achieved by locally thickening it. Various types of signal lines 3 are provided on the conductor layer 12, including straight, bent, and tortuous microstrip or stripline structures. Some signal lines 3 can be arranged in differential pairs along signal-dense areas, and some signal lines 3 are supplemented with local shielding lines around their perimeter to enhance anti-interference capabilities. Signal line 3 is connected to blind via 13 via copper plating structure 2. Blind via 13 penetrates part of dielectric layer 11 along the axial direction. Its inner wall is coated with copper to form copper pillars. The thickness of the copper plating can be adjusted according to the current carrying capacity and signal integrity requirements. The diameter of blind via 13 varies from micro-hole to meso-hole. A ring-shaped insulating structure is formed around blind via 13. This insulating ring 14 can be filled with epoxy resin, polyimide material or left empty along the edge of blind via 13 to ensure electrical isolation between the signal and blind via 13 and effectively control local parasitic capacitance and crosstalk.

[0024] Regarding the arrangement of blind vias 13, in this embodiment, the blind vias 13 can be arranged in a grid, oblique, staggered, or stepped manner to adapt to the spatial requirements of multi-layer high-density wiring, while reducing interlayer coupling and signal reflection. Some critical high-speed signal paths can use the superposition of blind vias 13 to form redundant conductive paths, improving reliability and vibration resistance. The circuit board body 1 has a ground plane 15 on the conductor layer 12 away from the high-speed signal line 3. The ground plane 15 can be a continuous copper foil layer, segmented copper foil, or a grid-like slotted design. The plane is connected to the copper plating structure 2 of the blind vias 13 through circular, square, or polygonal vias 16, making the grounding path continuous and uniform. At the same time, the locally thickened grounding posts can form a rigid support network with the blind vias 13, enhancing the mechanical strength and thermal conductivity of the circuit board. In some high-frequency signal areas, the grounding structure can add local shielding rings or embedded annular copper foil to form an isolation band and a miniature Faraday cage effect, further reducing electromagnetic interference and crosstalk.

[0025] Furthermore, the thickness of dielectric layer 11 and the depth of blind via 13 can be optimized to match the characteristics of signal line 3, ensuring impedance balance along the signal path and reducing reflections and parasitic coupling. The connection between signal line 3 and blind via 13 can employ a trapezoidal transition structure or a rounded corner transition structure to improve the transmission characteristics of signal via 16. The entire multilayer structure layout fully considers changes in thermal expansion, vibration, and humidity. The support network formed by the copper plating structure 2 of blind via 13 and the ground via 16 ensures the stability of the circuit board in complex automotive environments, enabling reliable transmission of high-speed signals in multilayer wiring. At the same time, the ground plane 15 and the shielding structure enhance electromagnetic compatibility and anti-interference capabilities.

[0026] In one embodiment, the signal line 3 is spaced apart from adjacent signal lines 3 by the dielectric 11, the thickness of the dielectric 11 and the thickness of the stacked dielectric 11 are both 50 μm, the width of the signal line 3 is 50 μm, the diameter of the blind via 13 is less than or equal to 0.1 mm, and the connection end of the signal line 3 and the blind via 13 is thickened with copper plating to form a pad 4.

[0027] In the above embodiment, the circuit board body 1 has multiple parallel signal lines 3. The signal lines 3 are 50 μm wide, extend along the surface of the conductor layer 12, and are separated from adjacent signal lines 3 by a dielectric 11. The thickness of the dielectric 11 spacing and the thickness of the stacked dielectric 11 layer are both 50 μm. The dielectric 11 layer is made of epoxy resin or polyimide composite material to ensure dielectric uniformity and mechanical stability. The signal lines 3 have a rectangular, slightly arc-shaped, or trapezoidal cross-section to reduce edge electric field concentration. Differential pair arrangement can also be used in local areas to improve common-mode interference immunity. Local shielding lines or ring-shaped auxiliary copper foil are added in dense wiring areas to optimize signal integrity. The blind via 13 has a diameter of less than or equal to 0.1 mm and penetrates part of the dielectric 11 layer axially. Its inner wall is plated with copper to form a continuous conductive pillar. The connection end between the signal line 3 and the blind via 13 is formed by thickened plated copper to form a pad 4. The pad 4 can be circular, elliptical, or trapezoidal with slight chamfering to optimize current carrying capacity and reduce local thermal stress, while providing a larger contact area to enhance soldering reliability. The transition between signal line 3 and blind via 13 can be rounded or gradually transitioned to ensure good impedance matching when high-speed signals pass through blind via 13. Blind vias 13 are arranged in an aligned, staggered, or stepped pattern along the wiring area to balance signal path density and mechanical support requirements, while also balancing the impedance of local signal paths. Through this structural design, high-speed signals can achieve stable transmission in multi-layer wiring, while the pads 4 and the copper plating structure 2 of blind via 13 provide sufficient mechanical support and thermal management capabilities, ensuring long-term reliability of the circuit board in complex automotive environments.

[0028] In one example, an annular or rectangular copper plating reinforcement 5 is formed on the outer periphery of the blind via 13 along the horizontal direction. A preset gap is provided between the copper plating reinforcement 5, the blind via 13, and the signal line 3. The preset gap is covered with solder resist ink 6.

[0029] In the above embodiments, a ring-shaped or rectangular copper reinforcement 5 is formed by horizontal copper plating around the outer periphery of the blind via 13. The thickness of this reinforcement is slightly greater than the thickness of the copper pillar of the blind via 13, and a preset gap is maintained between the reinforcement and the blind via 13 and the signal line 3. The gap can be uniformly annular, trapezoidal, or irregular polygonal to adapt to different blind via arrangements and signal densities. The preset gap is covered with solder resist ink 6, which can be an epoxy or polyimide coating with a thickness matching the outer diameter of the blind via 13 and the width of the signal line 3. This ensures electrical isolation and provides local mechanical protection to prevent short circuits between the copper reinforcement 5 and the signal line 3. The copper reinforcement 5 can be arranged entirely around the blind via 13 or in segments to provide additional mechanical support in critical high-speed signal areas, while reducing the displacement or deformation of the blind via 13 under multilayer stacking and vibration environments. A trapezoidal or rounded transition structure can be formed at the connection between the blind via 13 and the signal line 3 to optimize the transmission characteristics of the signal via 16 and prevent reflections caused by local impedance mismatch. The miniature support network formed by the reinforcing section and blind vias 13 can extend to the ground plane 15 and connect to the ground layer through local copper pillars or small vias 16, improving the overall stability of the multilayer structure. After covering the preset gaps, the solder resist ink 6 can achieve local contact or heat dissipation paths through local openings or thin film designs, while suppressing parasitic coupling of high-frequency signals. This structure ensures signal transmission integrity and electrical isolation while also increasing the mechanical strength and vibration resistance of the circuit board, enabling the automotive multilayer high-speed circuit board to maintain reliability during long-term use.

[0030] In one example, each conductor layer 12 in the circuit board body 1 is provided with an alignment hole 17, and the axis of the alignment hole 17 is perpendicular to the plane where the conductor layer 12 is located. The conductor layers 12 are stacked and positioned with each other through alignment holes 17, and the interlayer alignment of each conductor layer 12 is ±0.05mm.

[0031] In the above embodiment, each conductor layer 12 of the circuit board body 1 is provided with an alignment hole 17, the axis of which is perpendicular to the plane of the conductor layer 12. The alignment hole 17 can be circular, square, or polygonal, and the edges of the hole are processed with small chamfers or guide grooves to assist in stacking positioning and uniform stress distribution. The conductor layers 12 are precisely stacked and positioned with each other through the alignment hole 17, so that the interlayer alignment is controlled within ±0.05mm. The alignment hole 17 is arranged in a regular grid, diagonal, or staggered pattern along the plane to take into account the density of high-speed signal wiring and the alignment accuracy of blind vias 13 and vias 16. The alignment hole 17 is not only used for stacking positioning, but can also be extended to form heat dissipation channels or mechanical fixing points. Some areas can be filled with dielectric 11 or copper pillars to enhance structural rigidity. During the stacking process of conductor layers 12, the alignment hole 17 is coordinated with the copper pillars of blind vias 13, the ground plane 15, and the signal line 3 to ensure the alignment and impedance balance of the signal line 3, blind vias 13, and ground structure in multilayer wiring, thereby optimizing high-speed signal transmission characteristics and reducing crosstalk and reflection. Through the multi-layer stacked design with alignment holes 17, the circuit board remains stable under changes in thermal expansion, vibration, and humidity, improving overall mechanical strength and long-term reliability. Simultaneously, alignment holes 17 can be combined with locally thickened grounding copper pillars in critical areas to form a support network, providing additional mechanical stability for the copper plating of blind vias 13 and high-speed signal routing, and improving local electromagnetic compatibility.

[0032] In one example, a grounding wire 7 is also provided on the conductor layer 12. The grounding wire 7 is arranged parallel to the signal line 3 and extends along a first direction. The width of the grounding wire 7 is 50 μm.

[0033] In the above embodiment, in addition to the signal line 3, a ground line 7 is also provided on the conductor layer 12 of the circuit board body 1. The ground line 7 extends parallel to the signal line 3 along a first direction, with a width of 50μm. The cross-section can be rectangular or slightly arc-shaped to reduce the concentrated electric field and local current density at the edges. When the ground line 7 is arranged along the conductor layer 12, it is distributed at equal intervals with the signal line 3 and is insulated from the signal line 3 by a dielectric 11. At the same time, in critical high-speed signal areas, the ground line 7 can be locally widened or form a stepped width variation to improve the high-frequency signal return path and local impedance matching. The ground line 7 can form a continuous or segmented structure in the conductor layer 12. The segments are electrically connected to the lower ground plane 15 through micro-vias 16 to form a vertical loop and enhance electromagnetic shielding capability. In dense wiring areas, a micro-shielding ring or a local copper foil transition area can be added between the ground line 7 and the signal line 3 to reduce signal crosstalk and provide additional mechanical support for the copper plating structure 2 of the blind via 13. The entire grounding wire 7 network is coordinated with the signal wire 3 layout, so that the high-speed signal maintains stable impedance and uniform electric field distribution when it is transmitted between the conductor layers 12, while taking into account mechanical strength and thermal expansion control, ensuring the long-term reliability of the vehicle circuit board under vibration, temperature and humidity changes.

[0034] In one example, the circuit board body 1 is provided with a plurality of blind vias 13, the plurality of blind vias 13 are arranged in an array along the second direction, and the ground wire 7 is distributed between two signal lines 3; The insulating ring 14 is a hollow structure formed on the dielectric layer 11. The inner diameter of the insulating ring 14 is larger than the aperture of the blind via 13. The impedance control of the signal line 3 is maintained within a tolerance range of ±8% by controlling the thickness and linewidth of the dielectric layer 11.

[0035] In the above embodiment, the circuit board body 1 is provided with a plurality of blind vias 13, which are arranged in an array along the second direction. The blind vias 13 can be circular, elliptical or polygonal, and the spacing between them is determined according to the signal density and wiring requirements. The ground wire 7 is distributed between two adjacent signal lines 3, extending parallel to the first direction to form a continuous or segmented return path. The width of the ground wire 7 is the same as that of the signal line 3, which is 50μm, to ensure uniform impedance.

[0036] A hollow insulating ring 14, formed by dielectric 11 layers, is disposed around the blind via 13. The inner diameter of the insulating ring 14 is larger than the diameter of the blind via 13, and a portion of the conductor layer 12 is covered along the axial direction of the blind via 13. This ensures electrical isolation between the blind via 13 and the signal line 3, and also provides a stable connection surface for the signal line 3 via 16. The impedance of the signal line 3 is maintained within ±8% tolerance by controlling the thickness and linewidth of the dielectric 11. Simultaneously, micro-arc edge lines or trapezoidal cross-sections can be used locally to optimize high-frequency transmission characteristics. The blind vias 13 can be staggered or stepped along the array direction to improve signal density and mechanical support capabilities, while reducing interlayer coupling and crosstalk. A thin layer of solder resist ink 6 can be applied to the surface of the insulating ring 14 to form insulation protection and local mechanical buffering, ensuring stable conduction of the signal line 3 at the connection point of the blind via 13. Through this arrangement, high-speed signals can maintain balanced impedance and stable transmission in a multilayer structure, while the grounding wire 7 forms a uniform return path, improving electromagnetic shielding effectiveness and overall reliability.

[0037] In one embodiment, the vias 16 are distributed along the axial direction of the blind hole 13 on the outer periphery of the blind hole 13. When there are multiple vias 16, the multiple vias 16 are arranged in a circumferential array around the blind hole 13.

[0038] In the above embodiment, vias 16 are arranged axially around the blind vias 13 of the circuit board body 1. The vias 16 are electrically connected to the copper plating structure 2 of the blind vias 13 to enhance the grounding path and mechanical support. Multiple vias 16 are arranged in a circumferential array along the outer periphery of the blind vias 13. They can be circular, square, or polygonal in diameter, with uniform spacing to form a closed-loop support network. At the connection between the vias 16 and the blind vias 13 and the ground plane 15, rounded corners or small chamfers are formed to optimize the current return path and reduce high-frequency signal reflection. The copper plating thickness of the vias 16 can be slightly less than or equal to the copper plating pillar thickness of the blind vias 13 to balance signal transmission integrity and mechanical stability. At the same time, micro copper pillars or annular reinforcements can be added in local areas to provide additional mechanical support and prevent the blind vias 13 from shifting under multilayer stacking and thermal expansion conditions.

[0039] The via 16 arrangement, combined with the signal line 3 and ground line 7 layout, forms a continuous and uniform grounding loop. The ground plane 15, together with the blind via 13 and the copper plating of the via 16, forms a multi-layer rigid support network, enhancing the overall strength of the circuit board. The combined structure of the blind via 13 and via 16 can extend to the local shielding ring or micro-transition copper foil area, further optimizing the impedance of high-speed signal paths, suppressing parasitic coupling and crosstalk, and improving mechanical vibration resistance.

[0040] The present invention also provides a method for processing an on-board printed circuit board for an autonomous driving perception system, which is used to process the on-board printed circuit board for an autonomous driving perception system as described in any of the preceding claims, comprising: A laminated circuit board body 1 is provided, the circuit board body 1 comprising several layers of alternately stacked dielectric 11 and conductor layers 12; Drilling is performed on the opposite two end faces of the circuit board body 1 to form connected blind holes 13 and through holes, and copper plating is applied to the blind holes 13 to form a copper plating structure 2. Signal lines 3 connected to the copper plating structure 2 are etched on the conductor layer 12. An insulating ring 14 is formed around the connection between the blind via 13 and the signal line 3 on the conductor layer 12, with the blind via 13 as the rotation center.

[0041] In the above embodiments, the method for processing the vehicle-mounted printed circuit board for an autonomous driving perception system includes providing a laminated multilayer circuit board body 1. The circuit board body 1 is formed by alternately stacking several dielectric layers 11 and conductor layers 12. The dielectric layer 11 material can be epoxy resin or polyimide composite material, and the conductor layer 12 is copper foil or copper alloy. Subsequently, holes are drilled on opposite end faces of the circuit board body 1 to form axially connected blind vias 13 and through-holes. The diameter and depth of the blind vias 13 are controlled according to the arrangement of signal lines 3 and mechanical requirements. The via walls are formed into a continuous conductive structure by chemical copper plating or electroplating, so that a stable electrical connection is achieved between the signal lines 3 and the blind vias 13. On the conductor layer 12, signal lines 3 connected to the copper plating structure 2 of the blind vias 13 are formed by etching. The signal lines 3 can be straight, curved, or ring-shaped microstrip structures to adapt to different signal path layouts. An insulating ring 14 is formed around the rotation center of the blind via 13. The insulating ring 14 can be a hollow circular ring or a polygonal ring. It partially covers the conductor layer 12 along the axial direction of the blind via 13, ensuring electrical isolation between the blind via 13 and the signal line 3, and providing protective space for subsequent coating of solder resist ink 6. The entire method, through the cooperation of the blind via 13, the copper plating structure 2, the signal line 3, and the insulating ring 14, achieves precise conduction, electrical isolation, and multi-layer mechanical support for the high-speed signal path.

[0042] In one embodiment, during the process of etching signal lines 3 connected to the copper plating structure 2 on the conductor layer 12, a preset signal line 3 pattern is transferred to the surface of the conductor layer 12 using a micro-laser or optical exposure method, while multi-point heating is performed to make the dielectric 11 and the conductor layer 12 thermally expand uniformly.

[0043] In the above embodiments, the step of etching the signal line 3 connected to the copper plating structure 2 of the blind via 13 on the conductor layer 12 employs micro-laser or optical exposure technology to precisely transfer the preset signal line 3 pattern to the surface of the conductor layer 12. Micro-lasers can be used to engrave fine lines with micron-level precision in line width and spacing, while optical exposure achieves precise shaping of the signal pattern through photolithography, ensuring smooth and burr-free line edges. During the etching process of the signal line 3, a multi-point uniform heating method is used to ensure consistent thermal expansion of the dielectric layer 11 and the conductor layer 12, avoiding warping or signal impedance changes caused by localized stress concentration. The signal line 3 can be arranged with curved or annular microstrips along the rotation center of the blind via 13 to achieve impedance matching when the signal passes through the via 16. Simultaneously, micro-shielding structures or locally thickened copper foil are added along dense wiring areas to reduce crosstalk and parasitic capacitance. By combining micro-laser or optical exposure with multi-point thermal control, the accuracy of the signal line 3 pattern is ensured, while maintaining the structural stability of the dielectric layer 11 and conductor layer 12, providing reliable preconditions for subsequent processing of the insulating ring 14, coating with solder resist ink 6, and multilayer lamination.

[0044] In one embodiment, after the step of forming an insulating ring 14 around the connection between the blind via 13 and the signal line 3 on the conductor layer 12, the method further includes: Solder resist ink 6 is coated on the surface of conductor layer 12 and copper plating structure 2; The solder resist ink 6 is cured along the connection area between the edge of the blind hole 13 and the signal line 3 using directional hot air. During the coating process, the solder resist ink 6 does not enter the area of ​​the insulating ring 14.

[0045] In the above embodiment, after forming an insulating ring 14 around the connection between the blind via 13 and the signal line 3 on the conductor layer 12, solder resist ink 6 is further coated on the surface of the conductor layer 12 and the copper plating structure 2 of the blind via 13. The solder resist ink 6 is a photocurable or thermocurable epoxy resin-based coating. During the coating process, the ink is cured along the connection area between the edge of the blind via 13 and the signal line 3 by directional hot air control, while preventing the solder resist ink 6 from entering the hollow area of ​​the insulating ring 14, so as to maintain the electrical isolation and micro-support function of the insulating ring 14. The coating method can combine screen printing, spraying or brush coating to ensure uniform ink thickness. In local areas, the ink flow can be restricted by micro-baffles or templates.

[0046] During the directional hot air curing process, the hot air temperature and flow rate are precisely controlled to ensure that the solder resist ink 6 cures uniformly along the edge of the blind via 13, while keeping the interior of the insulating ring 14 clean to prevent short circuits or parasitic coupling. Simultaneously, the ink adheres tightly to the copper plating structure 2 of the blind via 13 and the surface of the conductor layer 12, improving mechanical strength and moisture resistance. This method ensures electrical protection at the connection between the blind via 13 and the signal line 3, while also enhancing the long-term stability of the high-speed signal transmission path and its durability and reliability in automotive environments.

[0047] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. An on-board printed circuit board for an autonomous driving perception system, characterized in that, The circuit board body (1) includes several layers of alternating dielectric (11) and conductor (12) layers. The circuit board body (1) has blind vias (13) along the conductor (12). The blind vias (13) penetrate at least part of the dielectric (11) layer along the axial direction, and the blind vias (13) have copper plating to form a copper plating structure (2). A signal line (3) is provided on the conductor layer (12). The signal line (3) is connected to a blind hole (13) through a copper plating structure (2). An insulating ring (14) is formed between the blind hole (13) and the signal line (3). The circuit board body (1) forms a ground plane (15) on a conductor layer (12) away from the signal line (3), and the ground plane (15) is connected to a blind via (13) through a via (16).

2. The vehicle-mounted printed circuit board for an autonomous driving perception system according to claim 1, characterized in that, The signal line (3) is spaced apart from the adjacent signal line (3) by the medium (11). The thickness of the medium (11) and the thickness of the stacked medium (11) are both 50 μm. The width of the signal line (3) is 50 μm. The diameter of the blind via (13) is less than or equal to 0.1 mm. The connection end of the signal line (3) and the blind via (13) is thickened with copper plating to form a pad (4).

3. The on-board printed circuit board for an autonomous driving perception system according to claim 1, characterized in that, The outer periphery of the blind hole (13) is formed with a ring-shaped or rectangular copper plating reinforcement (5) along the horizontal direction. A preset gap is provided between the copper plating reinforcement (5), the blind hole (13) and the signal line (3), and the preset gap is covered with solder resist ink (6).

4. The vehicle-mounted printed circuit board for an autonomous driving perception system according to claim 1, characterized in that, Each conductor layer (12) in the circuit board body (1) is provided with an alignment hole (17), and the axis of the alignment hole (17) is perpendicular to the plane where the conductor layer (12) is located; The conductor layers (12) are stacked and positioned by alignment holes (17), and the interlayer alignment of each conductor layer (12) is ±0.05mm.

5. The on-board printed circuit board for an autonomous driving perception system according to claim 1, characterized in that, A grounding wire (7) is also provided on the conductor layer (12). The grounding wire (7) is arranged parallel to the signal line (3) and extends along the first direction. The width of the grounding wire (7) is 50 μm.

6. The vehicle-mounted printed circuit board for an autonomous driving perception system according to claim 5, characterized in that, The circuit board body (1) is provided with a plurality of blind holes (13), the plurality of blind holes (13) are arranged in an array along the second direction, and the ground wire (7) is distributed between two signal lines (3); The insulating ring (14) is a hollow structure formed on the dielectric (11) layer. The inner diameter of the insulating ring (14) is larger than the aperture of the blind hole (13). The impedance control of the signal line (3) is maintained within ±8% tolerance by controlling the thickness and line width of the dielectric (11).

7. The on-board printed circuit board for an autonomous driving perception system according to claim 1, characterized in that, The vias (16) are distributed along the axial direction of the blind hole (13) on the outer periphery of the blind hole (13). When there are multiple vias (16), the multiple vias (16) are arranged in a circular array around the blind hole (13).

8. A method for processing an on-board printed circuit board for an autonomous driving perception system, characterized in that, For processing the vehicle-mounted printed circuit board of the autonomous driving perception system as described in any one of claims 1 to 7, comprising: A laminated circuit board body is provided, the circuit board body comprising several layers of alternately stacked dielectric and conductor layers; Drill holes on opposite ends of the circuit board body to form connected blind holes and through holes, and then deposit copper on the blind holes to form a copper deposit structure. Signal lines connected to the copper plating structure are etched on the conductor layer. An insulating ring is formed around the connection between the blind via and the signal line on the conductor layer, with the blind via as the rotation center.

9. A method for processing an on-board printed circuit board for an autonomous driving perception system according to claim 8, characterized in that, During the process of etching signal lines connected to the copper plating structure on the conductor layer, a pre-defined signal line pattern is transferred to the surface of the conductor layer using a micro-laser or optical exposure method, while multi-point heating is performed to ensure uniform thermal expansion of the dielectric and conductor layers.

10. A method for processing an on-board printed circuit board for an autonomous driving perception system according to claim 8, characterized in that, After the step of forming an insulating ring around the connection between the blind via and the signal line on the conductor layer, the method further includes: Solder resist ink is applied to the surface of the conductor layer and the copper plating structure. Directional hot air is used to cure the solder resist ink along the connection area between the blind via and the signal line, wherein the solder resist ink does not enter the insulating ring area during the coating process.

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