PCB wiring structure and wiring method

Abstract

The invention discloses a PCB wiring structure and a wiring method. The PCB wiring structure comprises a first layer board, a second layer board, a third layer board, a fourth layer board, a fifth layer board, a sixth layer board, a seventh layer board and an eighth layer board which are sequentially connected from top to bottom, through holes are formed among the first layer board, the second layer board, the third layer board and the fourth layer board, copper plating layers are arranged on the hole walls of the through holes, and copper plating layers are arranged on the copper plating layers. The copper plating layer located in the area of the third layer board is electrically connected with a surface layer circuit, through drill holes are formed among the fifth layer board, the sixth layer board, the seventh layer board and the eighth layer board, and the drill holes are communicated with the through holes. According to the invention, the problem of lead residue is avoided, the residual lead does not need to be processed subsequently, the production cycle of the PCB is shortened, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of PCB wiring, and in particular to a PCB wiring structure and a wiring method. Background Art

[0002] The conventional method of gold-plating gold fingers is to pull the lead wires at the end of the finger PIN (pin) and then conduct gold plating. However, this method has the following disadvantages: the residual lead wires need to be etched again, and all the signals of the gold fingers have residual lead stubs (residual stumps). The residual lead wires need to be processed later, resulting in a long PCB production cycle and high costs. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a PCB wiring structure and a wiring method.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] In a first aspect, an embodiment of the present invention provides a PCB wiring structure, comprising: a first layer board, a second layer board, a third layer board, a fourth layer board, a fifth layer board, a sixth layer board, a seventh layer board, and an eighth layer board connected in sequence from top to bottom, a through hole is provided between the first layer board, the second layer board, the third layer board, and the fourth layer board, the hole wall of the through hole is provided with a copper-plated layer, the copper-plated layer located in the third layer board area is electrically connected to a surface circuit, a through drill hole is provided between the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and the drill hole is communicated with the through hole.

[0006] In a specific embodiment, the through hole and the drilled hole are both circular.

[0007] In a specific embodiment, the diameter of the drilled hole is larger than that of the through hole.

[0008] In a specific embodiment, the aperture of the through hole is 8 mi l or 10 mi l or 12 mi l.

[0009] In a specific embodiment, the diameter of the drill hole is 14mil-18mil.

[0010] In one embodiment, the first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board have the same thickness.

[0011] In a specific embodiment, the thickness of the first layer is 0.1 mm-0.3 mm.

[0012] In a specific embodiment, the seventh layer is a ground layer.

[0013] In a specific embodiment, the fourth layer board and the fifth layer board are power supply layers.

[0014] The PCB wiring structure of the present invention has the following beneficial effects compared with the prior art: a through hole is provided between the first layer board, the second layer board, the third layer board, and the fourth layer board, the hole wall of the through hole is provided with a copper-plated layer, the copper-plated layer located in the third layer board area is electrically connected to the surface circuit, and a through drill hole is provided between the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and the drill hole is connected with the through hole, thereby avoiding the problem of residual leads, and there is no need to process the residual leads later, thereby shortening the PCB production cycle and reducing the cost.

[0015] In a second aspect, an embodiment of the present invention provides a PCB wiring method, comprising the following steps:

[0016] Through holes are provided between the first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and copper plating is performed on the hole walls of the through holes to obtain a copper-plated layer;

[0017] Connect the surface circuits to the copper-plated layer located in the third layer board area;

[0018] Connecting gold-plated leads to the copper-plated layer located in the seventh-layer board area;

[0019] A back drilling operation is performed on the area between the through hole corresponding to the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board to obtain a penetrating drill hole, and the drill hole is connected to the through hole.

[0020] The PCB wiring method of the present invention has the following beneficial effects compared with the prior art: through holes are set between the first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and the hole wall of the through hole is copper-plated to obtain a copper-plated layer, and then the copper-plated layer located in the third layer board area is connected to the surface circuit, and then the copper-plated layer located in the seventh layer board area is connected to the gold-plated lead, and then the through hole corresponding to the area between the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board is back-drilled to obtain a through drill hole, and the drill hole is connected to the through hole, so that the problem of lead residue is avoided, and the residual lead does not need to be processed later, thereby shortening the PCB production cycle and reducing the cost.

[0021] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 A cross-sectional schematic diagram of a PCB wiring structure provided by the present invention;

[0024] Figure 2 A schematic diagram of the process flow of the PCB wiring method provided by the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0029] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0031] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0032] See also Figure 1 As shown, the present invention discloses a specific embodiment of a PCB wiring structure, comprising: a first layer board 10, a second layer board 20, a third layer board 30, a fourth layer board 40, a fifth layer board 50, a sixth layer board 60, a seventh layer board 70, and an eighth layer board 80 connected in sequence from top to bottom, a through hole 90 is provided between the first layer board 10, the second layer board 20, the third layer board 30, and the fourth layer board 40, a hole wall of the through hole 90 is provided with a copper-plated layer 100, and the copper-plated layer 100 located in the area of ​​the third layer board 30 is electrically connected to a surface circuit, and a through drill hole 110 is provided between the fifth layer board 50, the sixth layer board 60, the seventh layer board 70, and the eighth layer board 80, and the drill hole 110 is communicated with the through hole 90.

[0033] Specifically, a through hole 90 is provided between the first layer 10, the second layer 20, the third layer 30, and the fourth layer 40, and a copper-plated layer 100 is provided on the hole wall of the through hole 90. The copper-plated layer 100 located in the area of ​​the third layer 30 is electrically connected to the surface circuit. A through hole 110 is provided between the fifth layer 50, the sixth layer 60, the seventh layer 70, and the eighth layer 80, and the drill hole 110 is connected to the through hole 90, thereby avoiding the problem of residual leads. There is no need to process the residual leads later, shortening the PCB production cycle and reducing costs. In addition, the surface circuit is electrically connected to the copper-plated layer 100 in the area of ​​the third layer 30. This layout method makes the wiring more flexible, and the direction and position of the wires can be adjusted as needed, thereby optimizing the layout of the entire circuit board and reducing signal interference and electromagnetic radiation. In addition, a drill hole 110 connected to the through hole 90 is provided between the fifth layer 50 and the eighth layer 80. This design cleverly avoids the problem of lead residue that may occur in the traditional PCB manufacturing process. The lead residue not only affects the appearance quality of the circuit board, but may also have an adverse effect on the circuit performance. By making the drill hole 110 connected to the through hole 90, it can ensure that the lead is completely removed during the manufacturing process without subsequent processing, thereby simplifying the production process. In addition, since the lead residue problem is avoided, there is no need to process the residual lead later, which greatly shortens the production cycle of the PCB. At the same time, the simplification of the production process also means a reduction in production costs, including labor costs, material costs, and equipment use costs. In addition, through a fine wiring structure and reliable electrical connections, it helps to improve the overall reliability and stability of PCB products, reduce the risk of circuit failures caused by manufacturing defects such as lead residues, and improve the service life and performance of the product.

[0034] In one embodiment, the through hole 90 and the drill hole 110 are both circular.

[0035] Specifically, circular holes are the most common and standardized hole shapes in the PCB industry. The use of circular through holes 90 and drill holes 110 helps ensure the compatibility of PCBs with other electronic components and systems. This standardized design makes it easier for PCBs to be connected and integrated with other circuit boards or electronic devices. In addition, in the PCB manufacturing process, the drilling process 110 of circular holes is relatively simple and easy to control. The circular drill bit can maintain high accuracy and consistency when drilling the holes 110, which helps to reduce errors and scrap rates in the production process; in addition, the edges of the circular holes are relatively smooth, which is conducive to subsequent copper plating, welding and other process treatments. In addition, the circular through holes 90 and drill holes 110 perform well in electrical performance. They can effectively provide electrical connection channels to ensure smooth transmission of current and signals between different layers. The design of the circular holes also helps to reduce signal interference and electromagnetic radiation, and improve the overall performance of the circuit board. In addition, the circular holes also have certain advantages in mechanical strength. Since the circular structure has good uniformity and symmetry, the circular through holes 90 and drill holes 110 can better withstand mechanical stress and impact, which is crucial to improving the durability and reliability of the PCB board.

[0036] In one embodiment, the diameter of the drilled hole 110 is larger than that of the through hole 90 .

[0037] Specifically, in the initial setting, a through hole 90 is provided between the first layer 10 to the eighth layer 80, and the hole wall of the through hole 90 is provided with a copper-plated layer 100. Then, a drilling hole 110 is set to cover the through hole 90 between the fifth layer 50 to the eighth layer 80 and remove the corresponding copper-plated layer 100 to avoid short circuit problems during subsequent use of the PCB, so that the PCB can be used normally.

[0038] In one embodiment, the aperture of the through hole 90 is 8 mi l, 10 mi l, or 12 mi l.

[0039] Specifically, through holes 90 of different apertures have different current carrying capacities. According to industry experience and simulation results, an aperture of 12mil can safely carry a current of about 1.2A. Although larger apertures (such as 16mil, 20mil, and even 24mil) do not increase linearly in current carrying capacity, apertures of 8mil, 10mil, and 12mil can usually meet the current carrying requirements of most conventional PCB designs. In addition, using through holes 90 of these standard apertures, designers can more flexibly layout and connect components on the circuit board without customizing tools or processes for specific apertures, which helps to improve design efficiency and reduce the increase in manufacturing costs that may be caused by non-standard apertures. In addition, apertures of 8mil, 10mil, and 12mil provide a good balance between manufacturing cost and performance; smaller apertures (such as 8mil) can save wiring space and reduce parasitic capacitance, which is suitable for high-speed circuit design; and larger apertures (such as 12mil) are easier to process and manufacture, and have a higher current carrying capacity. Designers can choose the appropriate aperture size according to specific needs.

[0040] In one embodiment, the borehole 110 has a diameter of 14 mi l-18 mi l.

[0041] Specifically, the main purpose of drilling 110 is to cover and remove the unnecessary copper plating layer 100 in the through hole 90 between the multilayer boards. In the multilayer PCB board, the through hole 90 is used to realize the electrical connection between the layers, but not all through holes 90 between the layers need to be completely copper plated. By drilling 110 and controlling the aperture within the range of 14mil-18mil, these redundant copper plating layers 100 can be accurately removed to avoid signal interference, electromagnetic radiation or short circuit problems. In addition, the aperture size of the drilling hole 110 needs to strike a balance between manufacturing cost and performance. Although a smaller aperture can save materials and improve signal integrity, it will increase the difficulty and cost of drilling 110; and although a larger aperture is easy to process, it may take up more wiring space and reduce signal transmission efficiency. The aperture range of 14mil-18mil is usually a more reasonable choice, which can meet performance requirements and control manufacturing costs.

[0042] In one embodiment, the first layer board 10 , the second layer board 20 , the third layer board 30 , the fourth layer board 40 , the fifth layer board 50 , the sixth layer board 60 , the seventh layer board 70 , and the eighth layer board 80 have the same thickness.

[0043] Specifically, when the thickness of all layers is the same, manufacturers can use unified process parameters and equipment to process all layers, thereby simplifying the manufacturing process and improving production efficiency, which helps to reduce production costs and reduce quality problems that may be caused by process differences. In addition, the same layer thickness helps to ensure the consistency of electrical and mechanical properties between layers. In multi-layer PCBs, the consistency between layers is crucial for signal transmission, electromagnetic compatibility (EMC) and mechanical strength. In addition, when designing the PCB stacking structure, if the thickness of all layers is the same, designers can more easily determine the arrangement order and thickness distribution of each layer, which helps to optimize the electrical performance, heat dissipation performance and manufacturing cost of the PCB. In addition, the same layer thickness helps to reduce stress concentration and mechanical failure problems that may be caused by differences in thickness between layers, which helps to improve the reliability and service life of the PCB. In addition, in the subsequent processing and assembly of the PCB, such as punching, electroplating, welding and other processes, if the thickness of all layers is the same, it is easier to control the processing accuracy and assembly quality.

[0044] In one embodiment, the thickness of the first layer 10 is 0.1 mm-0.3 mm.

[0045] Specifically, thinner board thickness (such as 0.1mm-0.3mm) allows more components and traces to be arranged in a limited space, thereby improving the integration of the PCB, which is particularly important for designing microelectronic products such as smartphones, wearable devices, medical devices, etc., because these devices have very strict space requirements. In addition, thinner traces and thinner board thickness help reduce parasitic capacitance and inductance on the signal transmission path, reduce signal attenuation and interference, and thus improve the electrical performance of the PCB, which is particularly important for the design of high-speed and high-frequency circuits. In addition, thinner board thickness usually means a shorter current transmission path, thereby reducing resistance and heat generation; in addition, thinner board thickness also helps heat dissipate faster to the surrounding environment, improving the heat dissipation performance of the PCB, which is particularly important for high-power, high-heat components. In addition, providing board thickness options in the range of 0.1mm-0.3mm increases the flexibility and customizability of the design, and designers can choose the most suitable board thickness based on specific application requirements, component size, wiring density and other factors.

[0046] In one embodiment, the seventh layer board 70 is a ground layer.

[0047] Specifically, the ground plane provides a stable reference potential (usually 0V) for all components on the circuit board, which helps ensure that the signals in the circuit can be transmitted correctly because all signals are measured based on this common reference potential. In addition, the ground plane can effectively reduce electromagnetic interference. In high-speed, high-frequency circuits, changes in signals will generate electromagnetic fields, which may interfere with other signals. The ground plane provides a low-impedance path so that these electromagnetic fields can be quickly dissipated, thereby reducing interference. In addition, the ground plane helps improve the integrity of the signal. In a multi-layer PCB, the signal layer and the ground layer are arranged alternately to form a microstrip line or stripline structure. This structure can reduce the attenuation and reflection of the signal during transmission and improve the transmission quality of the signal. In addition, in a multi-layer PCB, the ground layer can greatly simplify the wiring process. Since the ground layer provides a low-impedance path for the entire layer, it can reduce the number of times the signal line crosses between layers, reducing the difficulty and cost of wiring.

[0048] In one embodiment, the fourth layer board 40 and the fifth layer board 50 are power supply layers.

[0049] Specifically, the main function of the power layer is to provide a stable power supply to each component on the circuit board. By setting the power layer as a special layer, it can be ensured that the power signal is minimally disturbed during transmission, thereby ensuring the stability of the power supply. In addition, the design of the power layer helps to reduce power noise and interference. In a multi-layer PCB, the power layer and the ground layer are arranged alternately to form a power plane and a ground plane. This structure can provide a low-impedance power loop, reduce the propagation of power noise on the circuit board, and reduce interference to other signal layers. In addition, the existence of the power layer also helps to improve signal integrity; since the power layer provides a stable power supply for the components on the circuit board, it can reduce signal distortion and errors caused by power fluctuations; in addition, the power layer can also serve as a shielding layer for the signal layer, further reducing crosstalk and interference between signals. In addition, in a multi-layer PCB, setting the power layer as a special layer can improve wiring density and flexibility. Since the power layer is not used for signal transmission, it can be placed inside the circuit board to provide more wiring space for the signal layer, which helps to achieve more complex circuit design and higher integration.

[0050] The PCB wiring structure is not limited to being applied to PCBs with eight layers, but can also be used for PCBs with other numbers of layers, such as 10, 12, or 14 layers, which will not be elaborated in detail here.

[0051] See also Figure 2 As shown, an embodiment of the present invention provides a wiring method, comprising the following steps:

[0052] S1, setting through holes between the first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board and performing copper plating operation on the hole walls of the through holes to obtain a copper-plated layer;

[0053] Specifically, the copper-plated layer is obtained by copper-plating the hole wall of the through hole, which can be used to achieve subsequent electrical connection with the surface layer circuit.

[0054] S2, connecting the surface circuit to the copper-plated layer located in the third layer board area;

[0055] Specifically, the copper-plated layer in the third layer board area is electrically connected to the surface layer circuit to restore the original signal.

[0056] S3, connecting the gold-plated lead to the copper-plated layer located in the seventh layer board area;

[0057] Specifically, by connecting the gold-plated leads, a false short circuit is formed to achieve the gold-plating operation of the gold fingers.

[0058] S4, back drilling is performed on the through hole corresponding to the area between the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board to obtain a through drill hole, and the drill hole is connected to the through hole.

[0059] Specifically, the copper plating of the through holes between the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board is eliminated by drilling to avoid subsequent short circuit problems, so that the PCB can be used normally.

[0060] The present invention arranges penetrating through holes between the first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and copper-plating the hole walls of the through holes to obtain a copper-plated layer, then connects the copper-plated layer located in the third layer board area to the surface circuit, then connects the copper-plated layer located in the seventh layer board area to the gold-plated lead, and then back-drills the area of ​​the through hole corresponding to the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board to obtain a penetrating drill hole, and the drill hole is connected to the through hole, thereby avoiding the problem of lead residue, and there is no need to process the residual lead later, thereby shortening the PCB production cycle and reducing the cost.

[0061] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present technical solution is within the protection scope of the present invention.

Claims

1. A PCB wiring structure, characterized in that: include: The first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board are connected in sequence from top to bottom, and a through hole is provided between the first layer board, the second layer board, the third layer board, and the fourth layer board, and the hole wall of the through hole is provided with a copper-plated layer, and the copper-plated layer located in the third layer board area is electrically connected to the surface circuit, and a through drill hole is provided between the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and the drill hole is connected to the through hole.

2. A PCB wiring structure according to claim 1, characterized in that: The through hole and the drill hole are both circular in shape.

3. A PCB wiring structure according to claim 2, characterized in that: The bore hole has a larger diameter than the through hole.

4. A PCB wiring structure according to claim 3, characterized in that: The aperture of the through hole is 8 mil, 10 mil or 12 mil.

5. A PCB wiring structure according to claim 3, characterized in that: The diameter of the drilled hole is 14 mil-18 mil.

6. A PCB wiring structure according to claim 1, characterized in that: The first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board have the same thickness.

7. A PCB wiring structure according to claim 6, characterized in that: The thickness of the first layer is 0.1 mm-0.3 mm.

8. A PCB wiring structure according to claim 1, characterized in that: The seventh layer of board is a ground layer.

9. A PCB wiring structure according to claim 1, characterized in that: The fourth layer board and the fifth layer board are power supply layers.

10. A PCB wiring method, characterized in that: The following steps are involved: Through holes are provided between the first layer board, the second layer board, the third layer board, the fourth layer board, the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board, and copper plating is performed on the hole walls of the through holes to obtain a copper-plated layer; Connect the surface circuits to the copper-plated layer located in the third layer board area; Connecting gold-plated leads to the copper-plated layer located in the seventh-layer board area; A back drilling operation is performed on the area between the through hole corresponding to the fifth layer board, the sixth layer board, the seventh layer board, and the eighth layer board to obtain a penetrating drill hole, and the drill hole is connected to the through hole.

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