Multilayer sampling circuit printed circuit board

Abstract

The embodiment of the utility model provides a multilayer sampling circuit printed circuit board, which comprises a substrate used for providing a supporting and wiring platform; the first conductive layer is arranged on the substrate and is used for bearing a plurality of signal transmission paths and realizing electrical connection among different layers; the second conducting layer is positioned above the first conducting layer, is isolated from the first conducting layer through an insulating material, and is provided with a special ground plane for reducing mutual influence among signals; the shielding structure is composed of a plurality of plated-through holes arranged in a specific area and aims to form a protection area around the signal transmission path so as to prevent inter-layer signal crosstalk and electromagnetic interference; and the microstrip line coupler is arranged on the first conductive layer and is used for forming controllable coupling between signal transmission paths of different layers. According to the scheme of the embodiment of the invention, the problems of inter-layer signal crosstalk and electromagnetic interference of the multi-layer sampling circuit printed circuit board under the condition of high-density wiring can be solved.

Description

Technical Field

[0001] This application relates to the field of electronic engineering technology, and particularly to a multi-layer sampling circuit printed circuit board. Background Art

[0002] A multi-layer sampling circuit printed circuit board is a specific circuit design used in a multi-layer circuit board structure. This circuit board can provide a high-density line layout within a limited space and support high-speed data transmission and precise sampling functions. However, in the case of high-density wiring, this type of circuit board faces serious problems of inter-layer signal crosstalk and electromagnetic interference (EMI); signal crosstalk refers to the interference problem between signals caused by partial or complete coupling of the electromagnetic energy emitted on one signal line to other signal lines; and electromagnetic interference is the influence of non-desired frequency signals generated by external sources or other devices during high-frequency operation. Both of these can reduce the performance and reliability of the entire circuit. Therefore, how to effectively suppress inter-layer signal crosstalk and electromagnetic interference has become a key technical challenge that needs to be urgently solved. Summary of the Invention

[0003] In view of this, embodiments of the present disclosure provide a multi-layer sampling circuit printed circuit board, which at least partially solves the problems existing in the prior art.

[0004] This application provides a multi-layer sampling circuit printed circuit board, including:

[0005] A substrate for providing a support and wiring platform;

[0006] A first conductive layer disposed on the substrate for carrying a plurality of signal transmission paths and realizing electrical connection between different layers;

[0007] A second conductive layer located above the first conductive layer and grounded, and isolated from the first conductive layer by an insulating material layer;

[0008] A shielding structure including one or more inner conductive layers disposed between the first conductive layer and the second conductive layer, and a plurality of buried metallized holes are provided between the one or more inner conductive layers;

[0009] A microstrip line coupler disposed on the first conductive layer for forming a controllable coupling between signal transmission paths of different layers.

[0010] Preferably, one or more blind vias are provided on the second conductive layer, and the blind vias penetrate at least one insulating material layer to reach the first conductive layer.

[0011] Preferably, the blind vias terminate at the surface of the first conductive layer.

[0012] Preferably, a third conductive layer is added between the first conductive layer and the second conductive layer, and the third conductive layer includes a grounding design.

[0013] Preferably, the microstrip line coupler adopts a coplanar waveguide (CPW) structure.

[0014] Preferably, a filler layer is mixed in the substrate material.

[0015] Preferably, a plurality of copper foil filling areas for heat conduction are provided on the top layer of the substrate.

[0016] The shielding structure design adopts trapezoidal metallized holes.

[0017] Preferably, a fourth conductive layer is added, and point-to-point interconnection with the third conductive layer is achieved through micro-holes.

[0018] Preferably, an embedded filtering device is specially designed at the edge of the substrate.

[0019] The embodiment of the present disclosure provides a multilayer sampling circuit printed circuit board, including: a substrate for providing a support and a wiring platform; a first conductive layer disposed on the substrate for carrying a plurality of signal transmission paths and realizing electrical connection between different layers; a second conductive layer located above the first conductive layer and isolated from it by an insulating material, which is designed with a dedicated ground plane to reduce the mutual influence between signals; a shielding structure composed of a plurality of metallized holes arranged in specific areas, aiming to form a protection area around the signal transmission path to prevent inter-layer signal crosstalk and electromagnetic interference; a microstrip line coupler disposed on the first conductive layer for forming a controllable coupling between signal transmission paths of different layers. Through the solution of the embodiment of the present disclosure, the problems of inter-layer signal crosstalk and electromagnetic interference in the multilayer sampling circuit printed circuit board under high-density wiring conditions can be solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present disclosure, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present disclosure, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 It is a schematic diagram of the structure of the multilayer sampling circuit printed circuit board of the present utility model;

[0022] Figure 2 It is an exploded perspective view of the structure of the multilayer sampling circuit printed circuit board of the present utility model;

[0023] Figure 3Exploded perspective view of the structural substrate of the present utility model;

[0024] Figure 4 Schematic diagram of the first conductive layer of the structure of the present utility model;

[0025] Figure 5 Schematic diagram of the second conductive layer of the structure of the present utility model.

[0026] In the figure: 1, substrate; 2, first conductive layer; 3, embedded filtering device; 4, second conductive layer; 5, shielding structure; 6, microstrip line coupler; 7, metallized hole; 8, blind hole; 9, third conductive layer; 10, filler layer; 11, copper foil filling area; 12, fourth conductive layer. Detailed implementation mode

[0027] The following describes the embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0028] The following illustrates the implementation manners of the present disclosure through specific examples. Those skilled in the art can easily understand other advantages and effects of the present disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of them. The present disclosure can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts belong to the scope of protection of the present disclosure.

[0029] As Figure 1 and Figure 2 shown, a multi-layer sampling circuit printed circuit board 100 of the present application includes: a substrate 1, a first conductive layer 2, a second conductive layer 4, a shielding structure 5, and a microstrip line coupler 6.

[0030] The substrate 1 serves as the support structure for the entire circuit, providing an installation plane and necessary wiring space for subsequent components. According to specific design requirements, the substrate 1 is usually made of a dielectric material with excellent electrical properties, such as glass fiber reinforced epoxy resin board or other insulating materials suitable for high-frequency signals. At the same time, during the manufacturing process, the substrate 1 may be appropriately processed to improve the flatness of its surface and the consistency of electrical characteristics, thereby optimizing the working stability and reliability of the entire circuit board 100.

[0031] The first conductive layer 2 is disposed on the upper surface of the substrate 1. Multilayer circuits are formed through precise manufacturing processes such as electroplating, and techniques such as laser engraving or etching are used when necessary for fine line processes to accurately define signal transmission paths and electrical connection points. In addition, the first conductive layer 2 also includes various complex signal path designs and matching components to ensure the ability to carry out high-density signal exchanges between complex functional modules.

[0032] The second conductive layer 4 is located above the first conductive layer 2, and the two conductive materials are separated by an insulating layer of appropriate thickness in the middle. A dedicated ground plane (grounding) design is set on the second conductive layer 4. The purpose of this is to reduce the mutual influence when multiple signals are parallel, especially in a high-speed and high-frequency data processing environment. This is beneficial for improving the signal-to-noise ratio of the overall transmission, avoiding the occurrence of signal quality degradation, and ensuring the clarity and integrity of information during transmission.

[0033] The shielding structure 5 is composed of multiple metallized vias distributed around the periphery of each conductive layer to form an effective shielding barrier. Its purpose is to establish physical and electromagnetic protection around the signal traces, thereby preventing unnecessary leakage of signals between different circuit layers and the possible destructive interference of the external electromagnetic environment on the internal circuit operation, ensuring the safety and reliability of the key transmission link.

[0034] The microstrip line coupler 6 is placed at a suitable position on the surface of the first conductive layer 2 and combined with it. It is mainly used for controllable interaction of signal paths between adjacent or across layers, which is particularly crucial for advanced applications that require cross-layer signal synchronous transmission or phase tuning. The microstrip line coupler 6 allows engineers to regulate the energy distribution and transfer behavior in the circuit in a more flexible manner, further enhancing the system performance and expanding the device function coverage. Through such a design, the multilayer sampling circuit board can not only complete the signal transmission task in the traditional sense but also has stronger technology expansion capabilities and higher system design freedom.

[0035] In this application, the shielding structure 5 can include, for example, multiple conductive layers provided on the insulating substrate 1, such as the first conductive layer 2 and the second conductive layer 4 located on different surfaces of the insulating substrate 1 and one or more inner conductive layers in the middle. It should be noted that buried metallized vias 7 are added between these conductive layers. By arranging multiple buried metallized vias 7 at specific positions to construct an effective isolation barrier, and thereby enhancing the effective isolation of data paths between adjacent layers, enabling each functional module inside the entire printed circuit board to more safely and efficiently conduct data transmission and power delivery while reducing signal interference with each other.

[0036] The process of arranging and filling the buried metallized vias 7 during the manufacturing of a printed circuit board generally involves creating via channels using mechanical drilling, laser drilling, or other microfabrication techniques, and then depositing metal materials through appropriate plating or filling of electrolytes. This makes the buried metallized vias 7 not only serve as the conduction paths for vertical connections between multiple circuit layers but also act as a protective measure to prevent signal leakage between adjacent circuits and form unnecessary couplings. This can improve the overall performance of the printed circuit board and meet the requirements of high-density integration.

[0037] In one embodiment, as Figure 5 shown, in a multi-layer sampling circuit printed circuit board of the present application, blind vias 8 for connecting the first conductive layer 2 are provided on the second conductive layer 4. These blind vias 8 pass through one or more insulating materials provided between the second conductive layer 4 and the first conductive layer 2 and terminate at the surface of the first conductive layer 2, rather than penetrating the entire printed circuit board. This design can achieve effective connection of signals or power supplies, especially suitable for application environments that require dense connections and high-density layouts. By precisely designing the positions of the above-mentioned blind vias 8 and their electrical characteristics, the transmission quality of high-frequency or high-speed signals between different layers can also be improved, and noise interference can be effectively reduced, enhancing the EMC (electromagnetic compatibility) performance of the system.

[0038] To achieve this structural design, during the board manufacturing process, corresponding drill holes can be made at the required positions as the basis for future filling of metal conductive materials to form blind vias 8; then specific processes are used to remove unnecessary materials while retaining the via paths to ensure the formation of reliable conductors without affecting the rest of the circuit components or interconnect paths. Finally, through processes such as copper plating, the blind vias 8 are made to achieve reliable electrical connections, and the overall electrical characteristics of the circuit are ensured to be optimized. This process requires the manufacturer to have a high process accuracy to ensure precise positioning and good conductivity between the vias and the lines.

[0039] In one embodiment, in a multi-layer sampling circuit printed circuit board of the present application, a third conductive layer 9 is added between the first conductive layer 2 and the second conductive layer 4. This layer is mainly used for grounding design. As an independent layer, it can effectively shield electromagnetic interference from the inside and outside. Due to the presence of the third conductive layer 9, the overall PCB board has a better shielding effect, especially better suppression ability for electromagnetic noise during the transmission of signals with higher frequencies, thus significantly improving signal integrity and sampling accuracy. Further, in the actual application environment, such a design scheme helps to reduce the risk of data loss or signal distortion caused by EMI. In addition, this multi-layer design can not only effectively manage the separation of signal ground and power ground, avoid ground bounce phenomenon, but also optimize the layout of high-speed signal lines in a limited space and reduce the mutual interference between different signal layers.

[0040] To technically implement the above features, it can be clearly specified in the design stage that the third conductive layer 9 should use a complete metal copper plating as the ground plane, and there should be good electrical contact with other metal layers on the PCB to ensure its continuous and effective electromagnetic shielding function throughout the PCB. At the same time, during the manufacturing process, it is necessary to ensure the reliable connection between the third conductive layer 9 and surrounding components and proper insulation isolation from adjacent layers.

[0041] In one embodiment, as Figure 4 shown, for a multi-layer sampling circuit printed circuit board of the present application, in order to further improve its working performance and reduce various loss problems during signal transmission, a special design optimization is carried out on the microstrip line coupler 6. Specifically, by adopting a coplanar waveguide CPW structure as the basic framework, the circuit can achieve the purpose of optimizing the signal coupling efficiency without sacrificing manufacturing economy. Compared with traditional design methods, this new structure not only effectively improves the signal coupling performance, but also greatly reduces the radiation loss caused by conductor edge effects or non-uniformity. At the same time, due to the CPW structure having a lower characteristic impedance and a more uniform electric field distribution, it can better suppress interference in practical applications, especially the unnecessary electromagnetic interference that occurs between conductors close to each other due to space limitations on the circuit board.

[0042] To technically implement this optimization process, it is mainly to determine in the layout stage that the microstrip line coupler 6 is arranged in a coplanar waveguide manner with good electrical characteristics and a flat surface structure, and through precise computer-aided design software for simulation analysis and subsequent fine-tuning of parameter settings to ensure that the final product can achieve the expected technical goals. During this process, it is necessary to pay attention to finely adjusting geometric dimensions such as the width and spacing of the microstrip line to match the required frequency band range and achieve an efficient signal transmission function.

[0043] In one embodiment, refer to Figure 3, A multi-layer sampling circuit printed circuit board of the present application adds special treatment to the substrate 1 material on the basis of a traditional multi-layer circuit board, that is, specific types of fillers are mixed into the substrate 1 material. These filler layers 10 (such as carbon powder or other magnetic particles) can significantly change the electromagnetic wave absorption characteristics of the substrate 1. This innovation enables the printed circuit board PCB to effectively suppress internally generated noise at higher frequencies and also reduce interference caused by physical proximity between different circuit layers, which is particularly important in the design of high-density circuit wiring because high-frequency signals face serious signal integrity and EMI problems when propagating inside a multi-layer stacked structure. By adding these fillers, the present invention provides an effective solution. This modified substrate 1 can not only meet the requirements of high-speed digital signal transmission for lower losses, but also support higher levels of complexity and higher wiring density.

[0044] To technically achieve this feature, for example, during the manufacturing process, the influence degree of electromagnetic waves in a specific frequency band can be adjusted by controlling the mass ratio of magnetic particles or carbon powder added to the liquid resin precursor, and then a substrate 1 material with good characteristics is formed through high-temperature curing; or a spraying mixing process can be used to evenly distribute these fillers into the resin layer in the pre-curing stage before forming, so as to ensure that the obtained substrate 1 has excellent and consistent electromagnetic shielding performance and a low signal distortion rate, laying a solid foundation for constructing a high-performance sampling circuit PCB.

[0045] In one embodiment, as Figure 3 shown, in a multi-layer sampling circuit printed circuit board of the present application, a plurality of copper foil filling areas 11 for heat conduction are provided on the top layer of the substrate 1. These copper foil filling areas 11 enhance the heat dissipation function by increasing the heat conduction area and improving the heat diffusion performance of the material. The circuit board of this embodiment can quickly and effectively dissipate the heat generated during the operation of top-layer components in a high-frequency and high-current working environment, thereby helping to prevent circuit damage caused by overheating and maintaining the long-term stability and reliability of the circuit system. In addition, the reasonable distribution of the copper foil filling areas 11 also helps to reduce the influence of electromagnetic interference EMI generated by high-frequency operation, providing guarantee for the overall performance of the circuit.

[0046] To implement this feature, during the actual production and manufacturing process, a customized copper foil layout design can be carried out according to the working load and heat distribution of top-layer components. The specific methods include using CAD software to perform filling design on a preset area. By controlling the filling value and copper foil thickness parameters, these fillers can not only improve thermal conductivity but also take into account mechanical stability. Subsequently, at the corresponding stages in the PCB manufacturing process flow, such as copper deposition, electroplating, etc., the designed copper foil shape and distribution are precisely processed, thereby achieving the technical effects of improving heat dissipation and reducing EMI interference.

[0047] In one embodiment, for a multi-layer sampling circuit printed circuit board of the present application, in order to solve the problem of poor shielding effect of traditional round holes, especially the signal quality degradation and interference problems caused in a high-density wiring environment, a trapezoidal metallized hole design is adopted as part of the shielding structure 5. These trapezoidal holes can be closely arranged, which not only reduces the distance limitation between adjacent components but also provides a higher electromagnetic compatibility (EMComp) compatibility protection level by increasing the effective shielding area. The trapezoidal metallized hole design allows for more efficient coexistence between signal lines and the shielding layer, especially in high-frequency transmission applications with high requirements for signal purity. Compared with the traditional round hole design, the trapezoidal structure, due to its non-circular cross-section characteristics, greatly improves the wiring density in a limited space and reduces the possibility of cross-interference caused by proximal parallel traces.

[0048] For example, to implement the above technical feature, during manufacturing, a trapezoidal hole structure with customized hole wall angles and dimensions can be formed through special lithography techniques and etching steps in the PCB manufacturing process. This special-shaped metallized hole enables more precise operation accuracy in the alignment between multi-layer boards, thereby achieving the effects of enhancing shielding and reducing interference. In addition, it is crucial to use a tool with high-precision control during the drilling stage to establish this geometric shape, ultimately ensuring that the circuit board provides excellent performance and anti-interference capabilities across its entire frequency spectrum.

[0049] In one embodiment, for a multi-layer sampling circuit printed circuit board of the present application, in order to further increase the interconnection density and optimize the space utilization and electrical characteristics of the circuit board, a fourth conductive layer 12 is particularly added on the basis of the original design. By applying high-precision micro-hole technology, the fourth conductive layer 12 is designed to form reliable point-to-point electrical connections with the third conductive layer 9 located below it through a fine and precise via array. This point-to-point interconnection design method allows for a significant increase in the number of circuit interconnections per unit area while maintaining or even improving the circuit quality. Therefore, it not only supports a more compact and dense wiring arrangement but also maintains good signal integrity and low electromagnetic interference performance, which is extremely beneficial for applications that require a large number of circuit interconnections to be deployed in a smaller physical space.

[0050] For example, from a technical perspective, achieving this may require the use of laser drilling combined with electroplating filling or blind buried via technology to manufacture high-quality, fine-pitch, and reliable connection points in this way, and to ensure precise alignment and interconnection stability between the fourth conductive layer 12 and other underlying layers. This process involves solving the technical difficulties of precision machining and multi-layer alignment, as well as considerations on how to ensure that the micro-hole structure does not cause excessive signal transmission attenuation or reflection and other problems.

[0051] In one embodiment, as Figure 4 shown, an embedded filtering device 3 is specially designed at the edge of the substrate 1 of a multi-layer sampling circuit printed circuit board of the present application. The embedded filtering device 3 is configured to filter out various electromagnetic wave noise pollutions that can enter the printed circuit board PCB, aiming to reduce the influence of noise interference on the internal working signals of the system, provide a more stable and clean working environment for each electronic component on the PCB, and thus improve the operation performance and reliability of the entire device. This design integrated into the PCB itself is more compact and efficient than the traditional external filtering scheme, can reduce the space occupied by additional components, and optimize signal integrity and overall electrical performance at the same time.

[0052] Technically, this feature can be achieved by constructing the embedded filtering device 3 with an RF filter module containing specific inductance and capacitance values. This module can be designed according to the requirements of the involved frequency band and embedded into the appropriate layers of the PCB to effectively filter out high-frequency interference without affecting the existing circuit layout. In addition, by optimizing the position layout of the filter and the distance control from the key signal paths, the filtering function can be made more precise and targeted, thus achieving better effects.

[0053] During the actual operation process, when this device is in use, the substrate 1 provides a solid and flat installation platform, and all electronic components and signal lines are attached to it. A first conductive layer 2 is arranged on the substrate 1, and this layer undertakes the task of carrying multiple signal transmission paths. To ensure that these signal paths can be reliably connected to other components in the multi-layer sampling circuit printed circuit board, and to improve the quality and efficiency of electrical signal transmission, a series of precisely arranged metallized holes 7 and traces are designed. The second conductive layer 4 located above the first conductive layer 2 is deployed as an integral ground plane. This design effectively suppresses the problem of mutual interference of signals between layers, ensures that each signal path can operate in a relatively independent and less interfering environment, and further improves system stability and transmission speed.

[0054] In addition, the multi-layer sampling circuit printed circuit board is also specially equipped with a shielding structure 5. By arranging dense metallized vias 7 around the signal transmission path, the shielding structure 5 can construct a closed protection space, effectively blocking the interference signals from adjacent components or the external environment, and reducing the performance degradation caused by inter-layer signal crosstalk and external electromagnetic interference. More importantly, in this complex and precisely integrated design, the microstrip line coupler 6 located on the surface of the first conductive layer 2 plays an important role. Its function is to form a precisely controllable signal coupling in the signal path between different conductive layers 2 and 4, enabling high-frequency or high-precision signals to be stably transmitted across layers through this mechanism, thus achieving the high-performance operation of the entire multi-layer sampling circuit printed circuit board 100 and good signal processing effects.

[0055] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A multi-layer sampling circuit printed circuit board (100), characterized in that, Comprising: A substrate (1) for providing a support and wiring platform; A first conductive layer (2) disposed on the substrate (1) for carrying multiple signal transmission paths and realizing electrical connections between different layers; A second conductive layer (4) located above the first conductive layer (2) and grounded, and isolated from the first conductive layer (2) by an insulating material layer; A shielding structure (5) including one or more inner conductive layers disposed between the first conductive layer (2) and the second conductive layer (4), and a plurality of buried metallization holes (7) are provided between the one or more inner conductive layers; A microstrip line coupler (6) disposed on the first conductive layer (2) for forming a controllable coupling between signal transmission paths of different layers.

2. The printed circuit board of a multi-layer sampling circuit according to claim 1, wherein: One or more blind holes (8) are provided on the second conductive layer (4), and the blind holes penetrate at least one insulating material layer to reach the first conductive layer (2).

3. The multilayer sampling circuit printed circuit board according to claim 2, characterized in that: The blind hole (8) terminates at the surface of the first conductive layer (2).

4. A multilayer sampling circuit printed circuit board according to claim 1, wherein: A third conductive layer (9) is added between the first conductive layer (2) and the second conductive layer (4), and the third conductive layer (9) includes a grounding design.

5. A multi-layer sampling circuit printed circuit board according to claim 1, characterized in that: The microstrip line coupler (6) adopts a coplanar waveguide CPW structure.

6. A multi-layer sampling circuit printed circuit board according to claim 1, characterized in that: The substrate (1) material is mixed with a filler layer (10).

7. A multilayer sampling circuit printed circuit board according to claim 1, characterized in that: A plurality of copper foil filling areas (11) for heat conduction are provided on the top layer of the substrate (1).

8. A multi-layer sampling circuit printed circuit board according to claim 1, characterized in that: The shielding structure (5) is designed with trapezoidal metallization holes.

9. A multi-layer sampling circuit printed circuit board according to claim 1, characterized in that: A fourth conductive layer (12) is added and is interconnected point-to-point with the third conductive layer (9) through micro holes.

10. A multi-layer sampling circuit printed circuit board according to claim 1, characterized in that: An embedded filtering device (3) is specially designed at the edge of the substrate.

Images