Printed circuit board, slot and connector manufacturing method

Abstract

The present application discloses a method for manufacturing a printed circuit board, a slot and a connector, and relates to the field of electronic technology. The printed circuit board comprises: a first solder pad, a second solder pad, a first layer board, a signal layer board group and a second layer board stacked in sequence from bottom to top; the side of the first layer board is flush with the side of the second layer board; the signal layer board group comprises two adjacent layers of signal layer boards, the signal layer board has an extension portion, the extension portion protrudes from the side of the first layer board, and the extension portion is provided with a first solder pad; the surface of the first layer board and / or the surface of the second layer board is provided with a second solder pad, the first solder pad and the second solder pad form an electrical connection, and the first solder pad provided on a group of signal layer board groups is used to transmit a pair of differential signals. The implementation of the embodiment of the present application can transfer high-speed differential signals from the surface layer of the printed circuit board to the signal layer board on the inner layer of the printed circuit board, and then fan out to the gold finger, thereby improving the signal transmission quality and reducing the board area.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a method for manufacturing a printed circuit board, a slot, and a connector. Background Art

[0002] In a Kubernetes cluster (an open-source container orchestration engine), when the memory usage of a container service exceeds the configured value, i.e., when the container reaches a memory overflow state, the container will be unable to provide services for a short period of time. Furthermore, because other services in the cluster are still running, it is not possible to immediately restart the service to alleviate the memory pressure, as this would cause the entire cluster to crash. Therefore, conventional solutions to memory overflows often have a certain lag. In modern high-speed electronic systems, printed circuit boards (PCBs) are critical for device electrical connections and model transmission. Their structural design and routing patterns have a crucial impact on signal integrity. In particular, in high-speed differential signal transmission scenarios (such as high-speed interface protocols such as PCIe, USB, and HDMI), extremely high impedance matching accuracy is required for the transmission path. Currently, in modular circuit designs that use gold finger connectors as a pluggable connection method, differential signal lines are typically routed on the surface of the PCB and ultimately connected to the gold finger area to achieve physical and electrical connection to the module. However, the shortcomings of this surface routing method in practical applications have seriously affected the transmission quality of high-speed differential signals.

[0003] From the perspective of impedance control, surface differential traces lack a complete reference plane support, especially in the gold finger area. Due to the exposed surface and lack of a continuous ground plane, the impedance of the differential signal lines is difficult to accurately control. During high-speed differential signal transmission, if the impedance is discontinuous, memory will cause reflections and ringing, resulting in eye closure, increased jitter, and even increased bit error rates. Furthermore, surface traces are extremely susceptible to external electromagnetic interference, making the noise coupling effect more significant, further deteriorating signal transmission quality.

[0004] From a PCB layout perspective, fanning out differential signal traces through the PCB's surface layer to the gold fingers will increase the PCB's area. This is because the signals must switch layers through vias; isolation zones are required around the vias to prevent signal interference, and the signal traces after layer switching are concentrated on the PCB's surface layer. This increases the overall wiring area of ​​the PCB, making it difficult to reduce the board's size and hindering device miniaturization.

[0005] Based on the structure of the printed circuit board, the gold finger is connected to the slot by plugging. Inserting and removing the gold finger will cause the gold finger pad surface to wear and oxidize. The uneven stress on the gold finger during insertion and removal can cause the board to warp and crack, which will reduce the signal transmission quality. Summary of the Invention

[0006] The present application provides a method for manufacturing a printed circuit board, a slot, and a connector, which at least solves the problem of transmission quality of high-speed differential signals.

[0007] In a first aspect, the present application provides a printed circuit board, comprising: a first solder pad, a second solder pad, a first layer board, a signal layer board group, and a second layer board stacked sequentially from bottom to top;

[0008] The side edges of the first layer of board are flush with the side edges of the second layer of board;

[0009] The signal layer board group includes two adjacent signal layer boards, the signal layer boards have an extension portion, the extension portion protrudes from a side of the first layer board, and a first solder pad is provided on the extension portion;

[0010] A second pad is provided on the surface of the first layer board and / or the surface of the second layer board. The first pad is electrically connected to the second pad. The first pad provided on a group of signal layer boards is used to transmit a pair of differential signals.

[0011] Furthermore, the first layer board and / or the second layer board is provided with a conductive portion, and the conductive portion extends from the second solder pad along the thickness direction of the printed circuit board to the signal layer board group.

[0012] Furthermore, two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the conductive portion includes: a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer is provided between the conductive outer wall and the conductive inner wall;

[0013] The conductive outer wall is connected to a conductive trace of a signal layer in the signal layer board, and is used to transmit one signal in a pair of differential signals;

[0014] The conductive inner wall is connected to a conductive trace of another signal layer in the signal layer board, and is used to transmit the other signal in a pair of differential signals.

[0015] Furthermore, the conductive traces on the two signal layer boards in the signal layer board group overlap in the thickness direction of the printed circuit board.

[0016] Furthermore, a wiring obstacle area is provided on the straight segment path between the conductive portion and the first pad;

[0017] The conductive trace comprises: a first trace, an obstacle-avoiding trace, and a second trace;

[0018] The first and second traces are arranged along a straight line connecting the conductive portion and the first pad. One end of the first trace is electrically connected to the conductive portion, the other end of the first trace is electrically connected to one end of the obstacle bypass trace, the other end of the obstacle bypass trace is electrically connected to one end of the second trace, and the other end of the second trace is electrically connected to the first pad.

[0019] The distance between the obstacle avoidance routing and the edge of the wiring obstacle area is set.

[0020] Furthermore, the extension portion of the signal layer is arranged in a stepped shape in the thickness direction of the printed circuit board.

[0021] Furthermore, the signal layer board group has a first middle plane, and the number of signal layer boards arranged on both sides of the first middle plane is the same;

[0022] The extension portion of the signal layer board is symmetrically structured on both sides of the first middle plane.

[0023] Furthermore, the distance between the edge of the extension portion facing away from the side of the first layer board and the side of the first layer board decreases successively in the direction of the signal layer board adjacent to the middle plane pointing away from the first middle plane.

[0024] Furthermore, an edge of the extension portion facing away from the first layer of board is provided with a chamfer.

[0025] Furthermore, the printed circuit board includes at least two groups of signal layer boards, the at least two groups of signal layer boards have a second middle plane, and the number of signal layer boards arranged on both sides of the second middle plane is the same;

[0026] The chamfer of the signal layer disposed adjacent to the second middle plane has a first angle;

[0027] The chamfers of the remaining signal layer boards are at the second angle.

[0028] Further, the first angle is 30 degrees to 40 degrees;

[0029] The second angle is 15 degrees to 25 degrees.

[0030] Furthermore, the wide side of the first pad is arranged on the plane where the corresponding signal layer is located, along the chamfered edge;

[0031] The first pad has a pad width;

[0032] In the width direction of the pads, a preset spacing is provided between adjacent first pads;

[0033] The length of the first pad of the signal board layer disposed adjacent to the second middle plane is a first length;

[0034] The length of the first pads of the remaining signal layer boards is the second length.

[0035] Furthermore, two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the width of the first pad is W+0.1 mm to W+0.5 mm, where W represents the width of the conductive trace of the corresponding signal layer board;

[0036] The first length is 2.5 mm to 3 mm;

[0037] The second length is 3 mm to 3.5 mm;

[0038] The preset spacing is at least 0.2 mm.

[0039] Furthermore, in the direction of the second middle plane, a horizontal spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0040] Furthermore, the horizontal spacing is L = Y / 1.5, where L represents the horizontal spacing and Y represents the yield of the extension portion processed by the milling cutter.

[0041] Furthermore, the minimum value of the horizontal spacing is 0.6 mm.

[0042] Furthermore, in a direction perpendicular to the printed circuit board, a vertical spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0043] Furthermore, the minimum value of the vertical spacing is 0.5 mm.

[0044] Furthermore, a signal processing device is provided on the surface of the first layer board and / or the surface of the second layer board, and a pin for signal transmission in the signal processing device is electrically connected to the second pad.

[0045] In a second aspect, the present application further provides a slot adapted to fit a connector base formed by an extension of a signal layer board in the printed circuit board described in the first aspect;

[0046] The slot includes a third soldering pad. After the connector base is plugged into the slot, the third soldering pad forms an electrical connection with the corresponding first soldering pad.

[0047] In a third aspect, the present application further provides a connector manufacturing method for processing the connector base formed by the extension portion of the signal layer in the printed circuit board described in the first aspect to form a connector, comprising:

[0048] Lamination of printed circuit boards;

[0049] The connector base is obtained by laser cutting an extension portion of the signal layer board, wherein the extension portion of the signal layer board is pre-set with a first soldering pad;

[0050] The first pad is plated with gold to obtain a connector.

[0051] In a fourth aspect, the present application further provides a connector manufacturing method for processing the connector base formed by the extension portion of the signal layer in the printed circuit board described in the first aspect to form a connector, comprising:

[0052] Filling the extended portion of the signal layer with a gasket, and laminating the gasketed signal layer layer by layer;

[0053] Use a milling cutter to remove the spacers layer by layer to expose the extension of the corresponding signal layer;

[0054] peeling off the residual pad covering the surface of the extension portion of the corresponding signal layer board to expose the first pad of the corresponding signal layer board, where the first pad is preset on the extension portion of the signal layer board;

[0055] The first pad is plated with gold to obtain a connector.

[0056] Furthermore, a baffle is provided on the milling cutter column of the milling cutter, and the baffle is used to control the cutting depth of the milling cutter.

[0057] By implementing a method for manufacturing a printed circuit board, slot and connector as described in the embodiments of the present application. The high-speed differential signal is transferred from the surface layer of the printed circuit board to the signal layer board on the inner layer of the printed circuit board, and fanned out to the first pad corresponding to the signal layer board; the signal layer board extension portion and the first pad set thereon form a gold finger connector, and the gold finger connector is plugged into the motherboard to form a complete signal transmission link. On the one hand, by routing high-speed differential signals on the inner layer of the printed circuit board, the signal transmission quality is improved; on the other hand, the high-speed differential signal routing is dispersedly arranged on each inner layer signal layer board, which reduces the wiring space on the surface layer of the printed circuit board, thereby reducing the area of ​​the printed circuit board, which is conducive to product miniaturization.

[0058] The conductive portion connecting the surface layer of the printed circuit board with the inner signal layer is a coaxial blind via. Through this conductive portion, high-speed differential signals are connected to the adjacent signal layers. By aligning the traces of the two signal layers, which overlap along the thickness of the printed circuit board, high-speed differential signal transmission is achieved. This reduces the routing pressure of the differential signal traces on each signal layer, increases the routing freedom of the differential signal traces, and supports direct connection between the corresponding blind vias and the corresponding first pads. Transmitting a pair of differential signals through adjacent signal layers ensures the signal transmission quality of high-speed differential signals.

[0059] Conducting differential signal traces to the inner layers of the printed circuit board fan-out facilitates direct connections between the conductive portion and the first pad. This eliminates the need to design complex inner-layer signal traces to mitigate glass fiber effects. Instead, the inner-layer signal traces need only be routed around obstacles in the path directly connecting the conductive portion and the first pad. This improves routing freedom for high-speed differential signal traces. This direct, obstacle-circumventing connection between the conductive portion and the first pad reduces signal transmission distance and improves signal transmission quality.

[0060] The symmetrical, stepped connector base formed by the extension of the signal layer board on the inner layer of the printed circuit board provides uniform stress when inserting and removing the board, making the board less likely to warp or crack; the chamfered edge of the extension facilitates the board to be inserted into the slot through the connector base, thereby increasing the life of the board; the chamfered edge of the longest extension has a larger angle, which is conducive to its contact with the female connector and facilitates the insertion and removal of the board.

[0061] The size setting of the first pad is conducive to maintaining the continuity of high-speed signal impedance and avoiding reflection of high-speed signal transmission; the spacing setting between the first pads can avoid the risk of short circuit during plugging and unplugging assembly, and is conducive to improving the processing yield.

[0062] The manufacturing method of the connector is compatible with the existing process manufacturing process and has a high processing yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0064] Figure 1 This is a schematic diagram of a printed circuit board provided in an embodiment of the present application;

[0065] Figure 2 This is another schematic diagram of a printed circuit board provided in an embodiment of the present application;

[0066] Figure 3 is a top view of the conductive portion provided in an embodiment of the present application;

[0067] Figure 4 This is a schematic diagram of electronic components mounted on the surface of a printed circuit board provided in an embodiment of the present application;

[0068] Figure 5 This is a schematic diagram of an obstacle avoidance routing provided in an embodiment of the present application;

[0069] Figure 6This is another obstacle avoidance routing schematic diagram provided in an embodiment of the present application;

[0070] Figure 7 is a first intermediate plane schematic diagram provided in an embodiment of the present application;

[0071] Figure 8 is a second intermediate plane schematic diagram provided in an embodiment of the present application;

[0072] Figure 9 This is a schematic diagram of a slot provided in an embodiment of the present application;

[0073] Figure 10 This is a schematic diagram of a connector manufacturing method provided in an embodiment of the present application;

[0074] Figure 11 This is a schematic diagram of another connector manufacturing method provided in an embodiment of the present application;

[0075] Figure 12 is a schematic diagram of a gasket provided in an embodiment of the present application;

[0076] Figure 13 is a schematic diagram of a clamp provided in an embodiment of the present application;

[0077] Figure 14 This is a schematic diagram of the milling cutter column provided in an embodiment of the present application. DETAILED DESCRIPTION

[0078] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0079] Unless otherwise defined, technical or scientific terms used in this disclosure should have the same ordinary meaning as those of ordinary skill in the art to which this disclosure pertains. The terms "first," "second," and similar terms used in this disclosure do not denote any order, quantity, or importance, but are simply used to distinguish between different components. Similarly, terms such as "a," "an," or "the" do not denote a limitation of quantity, but rather denote the presence of at least one. The numbers in the drawings in this specification merely distinguish between various functional components or modules and do not indicate a logical relationship between the components or modules. Terms such as "include" or "comprising" mean that the element or object preceding the term includes the elements or objects listed after the term, and their equivalents, without excluding other elements or objects. Terms such as "connected" or "connected" are not limited to physical or mechanical connections but may include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," "right," "top," and "bottom" are used only to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0080] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Note that, in the accompanying drawings, the same reference numerals are given to components having substantially the same or similar structures and functions, and repeated descriptions thereof will be omitted.

[0081] In view of the problems in the prior art where high-speed differential signal routing on a printed circuit board is performed by switching layers to the top layer of the printed circuit board and then fanning out to the gold finger, which has high impedance matching requirements and is difficult to control signal transmission quality, this application provides the following implementation methods.

[0082] In some embodiments, as Figure 1 As shown, a printed circuit board includes: a first solder pad, a second solder pad, a first layer board, a signal layer board group and a second layer board stacked in sequence from bottom to top.

[0083] The sides of the first board are flush with the sides of the second board.

[0084] The signal layer board group includes two adjacent signal layer boards. The signal layer boards have an extension portion that protrudes from a side of the first layer board. A first solder pad is provided on the extension portion.

[0085] A second pad is provided on the surface of the first layer board and / or the surface of the second layer board. The first pad is electrically connected to the second pad. The first pad provided on a group of signal layer boards is used to transmit a pair of differential signals.

[0086] The first layer board and / or the second layer board are provided with a conductive portion, and the conductive portion extends from the second solder pad along the thickness direction of the printed circuit board to the signal layer board group.

[0087] Optionally, the number of the first layer board and the second layer board is one layer. The outer surface of the first layer board serves as the bottom surface of the printed circuit board, and the outer surface of the second layer board serves as the top surface of the printed circuit board.

[0088] The signal layer board set consists of a single set, with an extension protruding from one side of the first layer board. Within the signal layer board set, the extension forms a connector base, which forms a connector with a first solder pad located on its surface. The first solder pad is designed to form a good electrical connection with a corresponding solder pad on a mating female connector when the connector base is plugged into it, enabling signal transmission.

[0089] Preferably, in the signal layer board set, the extensions of the two signal layer boards protruding from the side of the first layer board have the same size, and the extensions are symmetrically stepped relative to the side of the first layer board.

[0090] The first pad on the signal layer board adjacent to the first layer board is arranged on the surface of the extended portion of the signal layer board facing the bottom surface of the printed circuit board.

[0091] The first pad on the signal layer board adjacent to the second layer board is arranged on the surface of the extended portion of the signal layer board facing the top surface of the printed circuit board.

[0092] Second solder pads are provided on the outer surface of the first layer (i.e., the bottom surface of the printed circuit board) and / or the outer surface of the second layer (i.e., the top surface of the printed circuit board). The second solder pads are used to connect to the pins of electronic components mounted on the top and / or bottom surfaces of the printed circuit board, and the pins of the electronic components are used to transmit signals.

[0093] Preferably, the transmitted signal is a differential signal.

[0094] Preferably, the differential signal is a high-speed differential signal.

[0095] The first pad and the second pad are electrically connected via a conductive portion extending from the second pad to the corresponding signal layer board group and a conductive trace connected to the conductive portion and disposed on the signal layer board.

[0096] In other embodiments, Figure 2 As shown, the number of first-layer boards is greater than one, and the number of second-layer boards is greater than one. The outer surface of the first-layer board disposed on the outermost side of the printed circuit board serves as the bottom surface of the printed circuit board; the outer surface of the second-layer board disposed on the outermost side of the printed circuit board serves as the top surface of the printed circuit board.

[0097] There are two signal layer board sets. The extension of the signal layer board in each set protrudes from the side edge of one side of the first layer board. The extension of the signal layer board in each set forms a connector base, which forms a connector with a first solder pad provided on its surface. The first solder pad is designed to form a good electrical connection with the corresponding solder pad on the female connector when the connector base is plugged into the corresponding female connector, thereby transmitting signals.

[0098] Preferably, in the two signal layer board groups, the extensions of the four signal layer boards protruding from the side edges of the first layer boards form a symmetrical stepped pattern relative to the side edges of the first layer boards. The extensions of the signal layer boards adjacent to the first layer boards and adjacent to the second layer boards are of the same size; the extensions of the two middle signal layer boards are of the same size. The extensions of the two middle signal layer boards are spaced farther from the edges of the side edges of the first layer boards than the extensions of the other two signal layer boards.

[0099] The first pads on the two signal layer boards close to the first layer board are arranged on the surfaces of the corresponding signal layer board extensions facing the bottom surface of the printed circuit board.

[0100] The first pads on the two signal layer boards close to the second layer board are arranged on the surfaces of the corresponding signal layer board extensions facing the top surface of the printed circuit board.

[0101] Second solder pads are provided on the outer surface of the first layer (i.e., the bottom surface of the printed circuit board) and / or the outer surface of the second layer (i.e., the top surface of the printed circuit board). The second solder pads are used to connect to pins of electronic components mounted on the top and / or bottom surfaces of the printed circuit board. These pins are used to transmit high-speed differential signals.

[0102] The first pad and the second pad are electrically connected via a conductive portion extending from the second pad to the corresponding signal layer board group and a conductive trace connected to the conductive portion and disposed on the signal layer board.

[0103] The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the conductive portion includes: a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer is provided between the conductive outer wall and the conductive inner wall;

[0104] The conductive outer wall is connected to a conductive trace of a signal layer in the signal layer board, and is used to transmit one signal in a pair of differential signals;

[0105] The conductive inner wall is connected to a conductive trace of another signal layer in the signal layer board, and is used to transmit the other signal in a pair of differential signals.

[0106] The conductive traces on the two signal layer boards in the signal layer board group overlap in the thickness direction of the printed circuit board.

[0107] The conductive portion is a blind hole, which is a type of via that extends from the second pad on the top or bottom surface of the printed circuit board to the signal layer board group corresponding to the second pad. Figure 3 A top view of the conductive portion is shown. The conductive portion is composed of a coaxially arranged conductive outer wall and conductive inner wall, along with an insulating layer disposed between the two walls. The insulating layer isolates the conductive outer wall from the conductive inner wall. Optionally, resin can be used as the insulating layer; copper can be used as the material for the conductive outer wall and the conductive inner wall; and copper can be used as the material for the conductive traces.

[0108] Optionally, the conductive outer wall is connected to a signal layer in the signal layer group that is closer to the second pad, and the conductive inner wall is connected to a signal layer in the signal layer group that is farther from the second pad. Each of these transmits one signal from a pair of differential signals. It is understood that a pair of differential signals is transmitted through a set of signal layer groups. Optionally, the conductive outer wall transmits the positive-phase signal Dp of the pair of differential signals, while the conductive inner wall transmits the negative-phase signal Dn of the pair of differential signals; vice versa is also possible.

[0109] The conductive part is manufactured by drilling a blind hole of a first diameter with the center of the second pad as the center to a signal layer in the corresponding signal layer group, copper-plating the inner wall and filling the via with resin, and then drilling a blind hole of a second diameter with the center of the via as the center to another signal layer in the signal layer group. The first diameter is larger than the second diameter, the conductive outer wall is connected to the signal layer closer to the second pad, and the conductive inner wall is connected to the signal layer farther from the second pad, such as Figure 4 As shown (for ease of description Figure 4 Only the connection components related to the device and the second pad are shown. When surface-mounting electronic components, one of the device's differential signal pins covers the surface of the second diameter via and is directly soldered to the conductive inner wall. The other pin of the same pair of differential signal pins can be soldered to the conductive inner wall via a connecting trace connected to the conductive outer wall. The arrangement of this connecting trace can be selected based on actual conditions and is not limited by this application. Illustratively, the first diameter is 0.25 mm to 0.3 mm, and the second diameter is 0.15 mm to 0.2 mm.

[0110] A signal processing device is provided on the surface of the first layer board and / or the surface of the second layer board, and a pin for signal transmission in the signal processing device is electrically connected to the second pad.

[0111] The signal processing device has differential signal pins. The differential signal pins appear in pairs, and the paired differential signal pins are respectively connected to the conductive inner wall and the conductive outer wall.

[0112] In the routing specifications for high-speed differential signal lines, taking 100 ohm differential impedance as an example, the spacing between a pair of differential signal lines is set at 0.1 mm to 0.2 mm. The thickness of a single-layer signal layer can be recorded as the thickness of the prepreg (since the prepreg is sandwiched between the conductive traces of the two signal layers). The thickness of the prepreg is generally between 0.075 mm and 0.19 mm, meeting the routing specifications for a pair of differential signal lines. Therefore, using two adjacent signal layers to transmit a pair of differential signals meets the high-speed differential signal routing specifications. To ensure impedance consistency and improve common-mode noise suppression, the conductive traces transmitting a pair of high-speed differential signals overlap along the thickness of the printed circuit board.

[0113] By switching the high-speed differential signal from the surface layer of the printed circuit board to the signal layer board on the inner layer of the printed circuit board, and fanning it out to the first pad corresponding to the corresponding signal layer board. Since the signal layer board extension and the first pad set on it form a gold finger connector, and the gold finger connector is plugged into the corresponding slot of the template, a complete signal transmission link is formed. On the one hand, switching the high-speed differential signal routing to the inner layer wiring of the printed circuit board can improve the impedance matching accuracy of the differential signal and enhance the signal transmission quality; on the other hand, the high-speed differential signal routing is dispersed on each inner layer signal layer board, which reduces the wiring space on the surface of the printed circuit board, thereby reducing the overall area of ​​the printed circuit board, which is conducive to product miniaturization.

[0114] The conductive portion connecting the surface layer of the printed circuit board (i.e., the top surface and / or bottom surface of the printed circuit board) and the inner signal layer board is composed of a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer arranged between the conductive outer wall and the conductive inner wall. The positive and negative ends of the high-speed differential signal are respectively transmitted to two model layers in a group of signal layer boards through coaxial blind holes serving as the conductive portion. By having the two layers of signal layer boards overlap with each other in the thickness direction of the printed circuit board, the transmission of high-speed differential signals is achieved, reducing the wiring pressure of the differential signal routing of each layer of signal layer board, increasing the wiring freedom of the differential signal routing, and supporting the direct connection of the corresponding blind hole with the corresponding first pad. The layered differential signal routing complies with the wiring specifications for high-speed differential signal routing. Transmitting a pair of differential signals through adjacent signal layer boards can ensure the signal transmission quality of the high-speed differential signal.

[0115] If there is a wiring obstacle area between the conductive part and the first pad that needs to be connected in a group of signal layer boards, it is necessary to add a detour route on the basis of directly connecting the conductive part and the corresponding first pad. The implementation method is as follows:

[0116] A wiring obstacle area is provided on the straight segment path between the conductive portion and the first pad.

[0117] The conductive trace includes: a first trace, an obstacle bypass trace, and a second trace; the first trace and the second trace are arranged along a straight line segment connecting the conductive portion and the first pad, one end of the first trace is electrically connected to the conductive portion, the other end of the first trace is electrically connected to one end of the obstacle bypass trace, the other end of the obstacle bypass trace is electrically connected to one end of the second trace, and the other end of the second trace is electrically connected to the first pad; the obstacle bypass trace is spaced apart from an edge of a wiring obstacle area.

[0118] The second trace is set up in the following way: Figure 5 As shown, the boundary of the wiring obstacle area is obtained; a minimum convex hull is set based on the boundary of the wiring obstacle area, and the minimum convex hull is a convex polygon with the minimum area that contains all points within the wiring obstacle area; two intersections of the minimum convex hull and the line connecting the conductive portion and the first pad are obtained, and the intersections include a first intersection and a second intersection, wherein the first intersection is located on one side of the conductive portion, and the second intersection is located on one side of the first pad; with the conductive portion as the starting point, the line is extended along the connection direction between the conductive portion and the first pad to a first position with a preset interval from the first intersection to obtain a first routing line; with the first pad as the starting point, the line is extended along the connection direction between the first pad and the conductive portion to a second position with a preset interval from the second intersection to obtain a second routing line; with the first position and the second position as the two end points of the obstacle avoidance route, the obstacle avoidance route is set along the edge of the minimum convex hull with a preset interval, wherein the obstacle avoidance route is set along the smaller side length of the minimum convex hull between the first intersection and the second intersection.

[0119] Methods for obtaining the minimum convex hull based on the boundary of the wiring obstacle region include, but are not limited to, Graham's method, Jarvis walk algorithm, divide-and-conquer algorithm, and Monotone Chain algorithm, etc., which will not be described in detail here.

[0120] On the basis of the above obstacle-avoiding routing, in order to improve the obstacle-avoiding routing along the minimum convex hull, corners will be introduced in the routing, causing problems such as signal reflection and impedance discontinuity. In some preferred embodiments, such as Figure 6 As shown, a minimum enclosing circle is set outside the minimum convex hull, and an obstacle bypass route is set along one side of the minor arc generated by the intersection of the minimum enclosing circle and the line connecting the conductive part and the first pad, with a preset interval between the minor arc and the minor arc.

[0121] The diameter of the minimum enclosing circle is the distance between the two vertices with the largest distance in the corresponding minimum convex hull.

[0122] The extension portion of the signal layer is arranged in a step-like shape in the thickness direction of the printed circuit board.

[0123] The stepped signal layer board extension portion enables each pad on the signal layer board to form a good electrical connection with the third pad of the corresponding slot after being plugged in.

[0124] Preferably, if Figure 7 As shown, the signal layer board group has a first middle plane, and the number of signal layer boards arranged on both sides of the first middle plane is the same.

[0125] The extension portion of the signal layer board is symmetrically structured on both sides of the first middle plane.

[0126] The distance between the edge of the extension portion facing away from the side of the first layer board and the side of the first layer board decreases in sequence in the direction of the signal layer board adjacent to the middle plane and away from the first middle plane.

[0127] Preferably, an edge of the extension portion facing away from the first layer board is provided with a chamfer.

[0128] The extension of the signal layer forms the connector base, and the first solder pad on the signal layer and the connector base form a connector for the printed circuit board. In order to improve the force uniformity of the connector base during the process of plugging or unplugging the connector from the corresponding slot, the stepped extension is arranged in a zigzag pattern relative to the first middle plane. Uniform stress is provided when plugging and unplugging the board, making it less likely for the board to warp or crack. The chamfers set on the edges of the extensions facilitate the plugging of the board into the slot through the connector base, thereby increasing the life of the board. The chamfer angle set on the longest edge of the extension is larger, which is beneficial for its contact with the female connector and facilitates the plugging and unplugging of the board.

[0129] Preferably, the printed circuit board comprises at least two groups of signal layer boards, and the at least two groups of signal layer boards have a second middle plane, and the number of signal layer boards arranged on both sides of the second middle plane is the same, such as Figure 8 shown.

[0130] The chamfer of the signal layer board disposed adjacent to the second middle plane has a first angle; the chamfers of the remaining signal layer boards have a second angle.

[0131] Preferably, the first angle is 30 to 40 degrees; the second angle is 15 to 25 degrees.

[0132] The chamfer angle is the angle between the chamfered edge and the plane of the signal layer. The first angle is larger than the second angle, facilitating contact and insertion between the connector base and the corresponding socket. The second angle is smaller than the first, ensuring uniform clamping force during insertion and protecting the edge of the first pad.

[0133] The wide side of the first pad is on the plane where the corresponding signal layer board is located and is arranged along the chamfered edge.

[0134] The first pad has a pad width.

[0135] In the pad width direction, a preset spacing is set between adjacent first pads; the length of the first pad of the signal layer arranged adjacent to the second middle plane is the first length; the length of the first pad of the remaining signal layer boards is the second length.

[0136] The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the width of the first pad is W+0.1 mm to W+0.5 mm, where W represents the width of the conductive trace of the corresponding signal layer board.

[0137] Setting the width of the first pad to the aforementioned width is beneficial for maintaining impedance continuity of the high-speed differential signal routing and avoiding reflections during high-speed signal transmission.

[0138] The first length is 2.5 mm to 3 mm; the second length is 3 mm to 3.5 mm.

[0139] Setting the first length and the second length within the above ranges is beneficial to the assembly and firmness of the board.

[0140] The preset spacing is at least 0.2 mm.

[0141] It can avoid the risk of short circuit when the connector is plugged in or unplugged; at the same time, it can also maintain the impedance continuity of high-speed differential signal transmission.

[0142] In the direction of the second middle plane, a horizontal spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0143] The horizontal spacing is L = Y / 1.5, where L represents the horizontal spacing and Y represents the yield of the extension machined using a milling cutter.

[0144] Preferably, the minimum value of the horizontal spacing is 0.6 mm.

[0145] The horizontal spacing setting is a compromise between process accuracy during the extension machining process and product performance. A smaller spacing can stretch the copper wire of the first pad during machining due to machining tolerances, causing short circuits. A larger spacing improves the board processing yield (a milling cutter is typically used for machining the extension). However, because connectors are slot-compatible, excessive spacing compresses the length of the first pad, affecting impedance matching and, in turn, signal transmission quality.

[0146] In a direction perpendicular to the printed circuit board, a vertical spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0147] The vertical spacing needs to be set to facilitate the processing of the extension.

[0148] The minimum vertical spacing is 0.5 mm. The thickness of the signal layer is usually 1.57 mm. This satisfies the above vertical spacing.

[0149] The size setting of the first pad is conducive to maintaining the continuity of high-speed signal impedance and avoiding reflection of high-speed signal transmission; the spacing setting between the first pads can avoid the risk of short circuit during plugging and unplugging assembly, and is conducive to improving the processing yield.

[0150] In other embodiments, Figure 9 As shown, a slot is adapted to a connector base formed by an extension portion of a signal layer board in the above-mentioned printed circuit board.

[0151] The slot includes a third soldering pad. After the connector base is plugged into the slot, the third soldering pad forms an electrical connection with the corresponding first soldering pad.

[0152] After the connector base is plugged into the slot, the first pad contacts the corresponding third pad, forming a good electrical connection for transmitting high-speed differential signals.

[0153] The printed circuit board specifically includes: a first solder pad, a second solder pad, a first layer board, a signal layer board group and a second layer board stacked in sequence from bottom to top;

[0154] The side edges of the first layer of board are flush with the side edges of the second layer of board;

[0155] The signal layer board group includes two adjacent signal layer boards, the signal layer boards have an extension portion, the extension portion protrudes from a side of the first layer board, and a first solder pad is provided on the extension portion;

[0156] A second pad is provided on the surface of the first layer board and / or the surface of the second layer board. The first pad is electrically connected to the second pad. The first pad provided on a group of signal layer boards is used to transmit a pair of differential signals.

[0157] The first layer board and / or the second layer board are provided with a conductive portion, and the conductive portion extends from the second solder pad along the thickness direction of the printed circuit board to the signal layer board group.

[0158] The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the conductive portion includes: a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer is provided between the conductive outer wall and the conductive inner wall;

[0159] The conductive outer wall is connected to a conductive trace of a signal layer in the signal layer board, and is used to transmit one signal in a pair of differential signals;

[0160] The conductive inner wall is connected to a conductive trace of another signal layer in the signal layer board, and is used to transmit the other signal in a pair of differential signals.

[0161] The conductive traces on the two signal layer boards in the signal layer board group overlap in the thickness direction of the printed circuit board.

[0162] A wiring obstacle area is provided on the straight segment path between the conductive portion and the first pad;

[0163] The conductive trace comprises: a first trace, an obstacle-avoiding trace, and a second trace;

[0164] The first and second traces are arranged along a straight line connecting the conductive portion and the first pad. One end of the first trace is electrically connected to the conductive portion, the other end of the first trace is electrically connected to one end of the obstacle bypass trace, the other end of the obstacle bypass trace is electrically connected to one end of the second trace, and the other end of the second trace is electrically connected to the first pad.

[0165] The distance between the obstacle avoidance routing and the edge of the wiring obstacle area is set.

[0166] The extension portion of the signal layer is arranged in a step-like shape in the thickness direction of the printed circuit board.

[0167] The signal layer board group has a first middle plane, and the number of signal layer boards arranged on both sides of the first middle plane is the same;

[0168] The extension portion of the signal layer board is symmetrically structured on both sides of the first middle plane.

[0169] The distance between the edge of the extension portion facing away from the side of the first layer board and the side of the first layer board decreases in sequence in the direction of the signal layer board adjacent to the middle plane and away from the first middle plane.

[0170] An edge of the extension portion facing away from the first layer of board is provided with a chamfer.

[0171] The printed circuit board includes at least two groups of signal layer boards, the at least two groups of signal layer boards have a second middle plane, and the number of signal layer boards arranged on both sides of the second middle plane is the same;

[0172] The chamfer of the signal layer disposed adjacent to the second middle plane has a first angle;

[0173] The chamfers of the remaining signal layer boards are at the second angle.

[0174] The first angle is 30 to 40 degrees;

[0175] The second angle is 15 degrees to 25 degrees.

[0176] The wide side of the first pad is on the plane where the corresponding signal layer is located and is arranged along the chamfered edge;

[0177] The first pad has a pad width;

[0178] In the width direction of the pads, a preset spacing is provided between adjacent first pads;

[0179] The length of the first pad of the signal board layer disposed adjacent to the second middle plane is a first length;

[0180] The length of the first pads of the remaining signal layer boards is the second length.

[0181] Two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the width of the first pad is W+0.1 mm to W+0.5 mm, where W represents the width of the conductive trace of the corresponding signal layer board;

[0182] The first length is 2.5 mm to 3 mm;

[0183] The second length is 3 mm to 3.5 mm;

[0184] The preset spacing is at least 0.2 mm.

[0185] In the direction of the second middle plane, a horizontal spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0186] The horizontal spacing is L = Y / 1.5, where L represents the horizontal spacing and Y represents the yield of the extension machined using a milling cutter.

[0187] The minimum horizontal spacing is 0.6 mm.

[0188] In a direction perpendicular to the printed circuit board, a vertical spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0189] The minimum vertical spacing is 0.5 mm.

[0190] A signal processing device is provided on the surface of the first layer board and / or the surface of the second layer board, and a pin for signal transmission in the signal processing device is electrically connected to the second pad.

[0191] In other embodiments, Figure 10 As shown, a connector manufacturing method is used to process the connector base formed by the extension portion of the signal layer board in the printed circuit board described in the first aspect to form a connector, comprising:

[0192] A100: Pressed printed circuit boards;

[0193] A200: A connector base is obtained by laser cutting an extension portion of a signal layer board, wherein a first solder pad is preset on the extension portion of the signal layer board;

[0194] A300: Gold plate the first pad to obtain a connector.

[0195] The printed circuit board specifically includes: a first solder pad, a second solder pad, a first layer board, a signal layer board group and a second layer board stacked in sequence from bottom to top;

[0196] The side edges of the first layer of board are flush with the side edges of the second layer of board;

[0197] The signal layer board group includes two adjacent signal layer boards, the signal layer boards have an extension portion, the extension portion protrudes from a side of the first layer board, and a first solder pad is provided on the extension portion;

[0198] A second pad is provided on the surface of the first layer board and / or the surface of the second layer board. The first pad is electrically connected to the second pad. The first pad provided on a group of signal layer boards is used to transmit a pair of differential signals.

[0199] The first layer board and / or the second layer board are provided with a conductive portion, and the conductive portion extends from the second solder pad along the thickness direction of the printed circuit board to the signal layer board group.

[0200] The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the conductive portion includes: a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer is provided between the conductive outer wall and the conductive inner wall;

[0201] The conductive outer wall is connected to a conductive trace of a signal layer in the signal layer board, and is used to transmit one signal in a pair of differential signals;

[0202] The conductive inner wall is connected to a conductive trace of another signal layer in the signal layer board, and is used to transmit the other signal in a pair of differential signals.

[0203] The conductive traces on the two signal layer boards in the signal layer board group overlap in the thickness direction of the printed circuit board.

[0204] A wiring obstacle area is provided on the straight segment path between the conductive portion and the first pad;

[0205] The conductive trace comprises: a first trace, an obstacle-avoiding trace, and a second trace;

[0206] The first and second traces are arranged along a straight line connecting the conductive portion and the first pad. One end of the first trace is electrically connected to the conductive portion, the other end of the first trace is electrically connected to one end of the obstacle bypass trace, the other end of the obstacle bypass trace is electrically connected to one end of the second trace, and the other end of the second trace is electrically connected to the first pad.

[0207] The distance between the obstacle avoidance routing and the edge of the wiring obstacle area is set.

[0208] The extension portion of the signal layer is arranged in a step-like shape in the thickness direction of the printed circuit board.

[0209] The signal layer board group has a first middle plane, and the number of signal layer boards arranged on both sides of the first middle plane is the same;

[0210] The extension portion of the signal layer board is symmetrically structured on both sides of the first middle plane.

[0211] The distance between the edge of the extension portion facing away from the side of the first layer board and the side of the first layer board decreases in sequence in the direction of the signal layer board adjacent to the middle plane and away from the first middle plane.

[0212] An edge of the extension portion facing away from the first layer of board is provided with a chamfer.

[0213] The printed circuit board includes at least two groups of signal layer boards, the at least two groups of signal layer boards have a second middle plane, and the number of signal layer boards arranged on both sides of the second middle plane is the same;

[0214] The chamfer of the signal layer disposed adjacent to the second middle plane has a first angle;

[0215] The chamfers of the remaining signal layer boards are at the second angle.

[0216] The first angle is 30 to 40 degrees;

[0217] The second angle is 15 degrees to 25 degrees.

[0218] The wide side of the first pad is on the plane where the corresponding signal layer is located and is arranged along the chamfered edge;

[0219] The first pad has a pad width;

[0220] In the width direction of the pads, a preset spacing is provided between adjacent first pads;

[0221] The length of the first pad of the signal board layer disposed adjacent to the second middle plane is a first length;

[0222] The length of the first pads of the remaining signal layer boards is the second length.

[0223] Two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the width of the first pad is W+0.1 mm to W+0.5 mm, where W represents the width of the conductive trace of the corresponding signal layer board;

[0224] The first length is 2.5 mm to 3 mm;

[0225] The second length is 3 mm to 3.5 mm;

[0226] The preset spacing is at least 0.2 mm.

[0227] In the direction of the second middle plane, a horizontal spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0228] The horizontal spacing is L = Y / 1.5, where L represents the horizontal spacing and Y represents the yield of the extension machined using a milling cutter.

[0229] The minimum horizontal spacing is 0.6 mm.

[0230] In a direction perpendicular to the printed circuit board, a vertical spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0231] The minimum vertical spacing is 0.5 mm.

[0232] A signal processing device is provided on the surface of the first layer board and / or the surface of the second layer board, and a pin for signal transmission in the signal processing device is electrically connected to the second pad.

[0233] In other embodiments, Figure 11 As shown, a connector manufacturing method is used to process the connector base formed by the extension portion of the signal layer board in the printed circuit board described in the first aspect to form a connector, comprising:

[0234] B100: Fill the extension of the signal layer with gaskets, such as Figure 12 As shown, the signal layer board filled with gaskets is laminated layer by layer;

[0235] B200: Use a milling cutter to remove the gasket layer by layer to expose the extension of the corresponding signal layer;

[0236] B300: peeling off the residual pad covering the surface of the extension portion of the corresponding signal layer board to expose the first pad of the corresponding signal layer board, where the first pad is preset on the extension portion of the signal layer board;

[0237] B400: Gold-plating the first pad to obtain a connector.

[0238] The printed circuit board specifically includes: a first solder pad, a second solder pad, a first layer board, a signal layer board group and a second layer board stacked in sequence from bottom to top;

[0239] The side edges of the first layer of board are flush with the side edges of the second layer of board;

[0240] The signal layer board group includes two adjacent signal layer boards, the signal layer boards have an extension portion, the extension portion protrudes from a side of the first layer board, and a first solder pad is provided on the extension portion;

[0241] A second pad is provided on the surface of the first layer board and / or the surface of the second layer board. The first pad is electrically connected to the second pad. The first pad provided on a group of signal layer boards is used to transmit a pair of differential signals.

[0242] The first layer board and / or the second layer board are provided with a conductive portion, and the conductive portion extends from the second solder pad along the thickness direction of the printed circuit board to the signal layer board group.

[0243] The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the conductive portion includes: a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer is provided between the conductive outer wall and the conductive inner wall;

[0244] The conductive outer wall is connected to a conductive trace of a signal layer in the signal layer board, and is used to transmit one signal in a pair of differential signals;

[0245] The conductive inner wall is connected to a conductive trace of another signal layer in the signal layer board, and is used to transmit the other signal in a pair of differential signals.

[0246] The conductive traces on the two signal layer boards in the signal layer board group overlap in the thickness direction of the printed circuit board.

[0247] A wiring obstacle area is provided on the straight segment path between the conductive portion and the first pad;

[0248] The conductive trace comprises: a first trace, an obstacle-avoiding trace, and a second trace;

[0249] The first and second traces are arranged along a straight line connecting the conductive portion and the first pad. One end of the first trace is electrically connected to the conductive portion, the other end of the first trace is electrically connected to one end of the obstacle bypass trace, the other end of the obstacle bypass trace is electrically connected to one end of the second trace, and the other end of the second trace is electrically connected to the first pad.

[0250] The distance between the obstacle avoidance routing and the edge of the wiring obstacle area is set.

[0251] The extension portion of the signal layer is arranged in a step-like shape in the thickness direction of the printed circuit board.

[0252] The signal layer board group has a first middle plane, and the number of signal layer boards arranged on both sides of the first middle plane is the same;

[0253] The extension portion of the signal layer board is symmetrically structured on both sides of the first middle plane.

[0254] The distance between the edge of the extension portion facing away from the side of the first layer board and the side of the first layer board decreases in sequence in the direction of the signal layer board adjacent to the middle plane and away from the first middle plane.

[0255] An edge of the extension portion facing away from the first layer of board is provided with a chamfer.

[0256] The printed circuit board includes at least two groups of signal layer boards, the at least two groups of signal layer boards have a second middle plane, and the number of signal layer boards arranged on both sides of the second middle plane is the same;

[0257] The chamfer of the signal layer disposed adjacent to the second middle plane has a first angle;

[0258] The chamfers of the remaining signal layer boards are at the second angle.

[0259] The first angle is 30 to 40 degrees;

[0260] The second angle is 15 degrees to 25 degrees.

[0261] The wide side of the first pad is on the plane where the corresponding signal layer is located and is arranged along the chamfered edge;

[0262] The first pad has a pad width;

[0263] In the width direction of the pads, a preset spacing is provided between adjacent first pads;

[0264] The length of the first pad of the signal board layer disposed adjacent to the second middle plane is a first length;

[0265] The length of the first pads of the remaining signal layer boards is the second length.

[0266] Two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the width of the first pad is W+0.1 mm to W+0.5 mm, where W represents the width of the conductive trace of the corresponding signal layer board;

[0267] The first length is 2.5 mm to 3 mm;

[0268] The second length is 3 mm to 3.5 mm;

[0269] The preset spacing is at least 0.2 mm.

[0270] In the direction of the second middle plane, a horizontal spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0271] The horizontal spacing is L = Y / 1.5, where L represents the horizontal spacing and Y represents the yield of the extension machined using a milling cutter.

[0272] The minimum horizontal spacing is 0.6 mm.

[0273] In a direction perpendicular to the printed circuit board, a vertical spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

[0274] The minimum vertical spacing is 0.5 mm.

[0275] A signal processing device is provided on the surface of the first layer board and / or the surface of the second layer board, and a pin for signal transmission in the signal processing device is electrically connected to the second pad.

[0276] When using a milling cutter, after the signal layer extension is prefabricated, peelable adhesive is applied to the stepped connector base to make the top and bottom surfaces of the printed circuit board flat. The peelable adhesive is removed layer by layer with a milling cutter to expose the first solder pad.

[0277] The thermal expansion coefficient of the strippable adhesive is similar to that of the printed circuit board substrate, ensuring a flat top and bottom surface during processing. After a single heating step, the strippable adhesive loses its tack and can be removed from the printed circuit board substrate and the first solder pad. A milling cutter penetrates the corresponding extension to remove the strippable adhesive. After milling the grooves, the strippable adhesive remaining on the extension is placed in a constant-temperature oven at the board transition temperature for 20-30 minutes to remove the remaining strippable adhesive. The board transition temperature refers to the temperature at which the substrate material transitions from a hard and relatively brittle state to a soft, highly elastic, rubbery state. Removing the remaining strippable adhesive at this temperature prevents thermal expansion of the printed circuit board, which can cause cracking in solder joints. It also prevents a decrease in the rigidity and strength of the printed circuit board, improving its durability during assembly and long-term reliability. Furthermore, it maintains the stability of the board substrate's electrical properties, such as the dielectric constant and dissipation factor, to ensure signal transmission quality.

[0278] The copper roughness of the first pad is less than 0.5 microns, which facilitates the peeling of the first pad from the peelable adhesive and helps reduce the transmission loss of high-speed differential signals.

[0279] Preferably, the diameter of the milling cutter is 0.4 mm to 0.5 mm to improve the machining accuracy of the milling groove extension.

[0280] Preferably, the travel speed of the milling cutter is at most 0.4 m / min to reduce the stress on the printed circuit board.

[0281] like Figure 13 As shown, when a milling cutter is used for processing, the printed circuit board is clamped in a fixture, and the height of the clamping portion on the side of the fixture can clamp the middle layer of the connector base, so that the printed circuit board is firmly fixed to the fixture during milling cutter processing.

[0282] like Figure 14 As shown, a baffle is provided on the milling cutter column of the milling cutter, and the baffle is used to control the cutting depth of the milling cutter.

[0283] The distance between the baffle and the milling cutter head is the distance between the top surface of the printed circuit board and the corresponding signal layer extension, or the distance between the bottom surface of the printed circuit board and the corresponding signal layer extension. When the milling cutter is lowered, the top or bottom surface of the printed circuit board blocks the baffle, thereby controlling the milling cutter's cutting depth, allowing the milling cutter to remove the peelable adhesive attached to the surface of the corresponding signal layer extension.

[0284] It should be understood that although Figure 10 、 Figure 11 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 10 、 Figure 11 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0285] By implementing a method for manufacturing a printed circuit board, slot and connector as described in the embodiments of the present application. The high-speed differential signal is transferred from the surface layer of the printed circuit board to the signal layer board on the inner layer of the printed circuit board, and fanned out to the first pad corresponding to the signal layer board; the signal layer board extension portion and the first pad arranged thereon form a gold finger connector, and the gold finger connector is plugged into the motherboard to form a complete signal transmission link. On the one hand, by routing high-speed differential signals on the inner layer of the printed circuit board, the signal transmission quality is improved; on the other hand, the high-speed differential signal routing is dispersedly arranged on each inner layer signal layer board, which reduces the wiring space on the surface layer of the printed circuit board, thereby reducing the area of ​​the printed circuit board, which is conducive to product miniaturization; on the other hand, it can also improve the design density of the gold finger board.

[0286] The conductive part connecting the surface layer of the printed circuit board and the inner signal layer board is a coaxial blind hole, through which the high-speed differential signal is connected to the adjacent signal layer boards respectively. The transmission of high-speed differential signals is achieved by the overlapping traces of the two signal layer boards in the thickness direction of the printed circuit board, further reducing the wiring pressure of the differential signal traces of each layer of signal layer boards, and transmitting a pair of differential signals through adjacent signal layer boards, which can ensure the signal transmission quality of the high-speed differential signal.

[0287] Conducting differential signal traces to the inner layers of the printed circuit board fan-out facilitates direct connections between the conductive portion and the first pad. This eliminates the need to design complex inner-layer signal traces to mitigate glass fiber effects. Instead, the inner-layer signal traces need only be routed around obstacles in the path directly connecting the conductive portion and the first pad. This improves routing freedom for high-speed differential signal traces. This direct, obstacle-circumventing connection between the conductive portion and the first pad reduces signal transmission distance and improves signal transmission quality.

[0288] The symmetrical, stepped connector base formed by the extension of the signal layer board on the inner layer of the printed circuit board provides uniform stress when inserting and removing the board, making the board less likely to warp or crack; the chamfered edge of the extension facilitates the board to be inserted into the slot through the connector base, thereby increasing the life of the board; the chamfered edge of the longest extension has a larger angle, which is conducive to its contact with the female connector and facilitates the insertion and removal of the board.

[0289] The size setting of the first pad is conducive to maintaining the continuity of high-speed signal impedance and avoiding reflection of high-speed signal transmission; the spacing setting between the first pads can avoid the risk of short circuit during plugging and unplugging assembly, and is conducive to improving the processing yield.

[0290] The manufacturing method of the connector is compatible with the existing process manufacturing process and has a high processing yield.

[0291] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0292] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as steps executed by a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program loaded on a computer-readable medium, and the computer program includes program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via a communication device, or installed from a memory, or installed from a ROM. When the computer program is executed by an external processor, the above-mentioned functions defined in the method of the embodiment of the present application are performed.

[0293] It should be noted that the computer-readable medium of the embodiments of the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the two. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the embodiments of the present application, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device or device. In the embodiments of the present application, the computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries a computer-readable program code. This propagated data signal may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or convey a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code embodied on the computer-readable medium may be conveyed using any suitable medium, including but not limited to wires, optical cables, RF (Radio Frequency), or any suitable combination thereof.

[0294] The computer-readable medium may be included in the server or may exist independently and not incorporated into the server. The computer-readable medium carries one or more programs that, when executed by the server, cause the server to: in response to detecting that the terminal's peripheral mode is inactive, obtain the frame rate of applications on the terminal; when the frame rate meets a screen-off condition, determine whether the user is currently accessing the terminal's screen information; and, in response to determining that the user is not accessing the terminal's screen information, control the screen to enter an immediate dimming mode.

[0295] Computer program code for performing the operations of embodiments of the present application can be written in one or more programming languages ​​or combinations thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., using an Internet service provider to connect via the Internet).

[0296] Each embodiment in this specification is described in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without expending creative work.

[0297] The above is a detailed introduction to the technical solutions provided by this application. Specific examples are used herein to illustrate the principles and implementation methods of this application. The description of the above embodiments is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the contents of this specification should not be understood as limiting this application.

[0298] The above is a detailed introduction to a method for manufacturing a printed circuit board, a slot, and a connector provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The above embodiments are only preferred embodiments of the present application, which are used to help understand the method and core ideas of the present application and are not intended to limit the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application, these improvements and modifications also fall within the scope of protection of the present application.

Claims

1. A printed circuit board, characterized in that include: A first solder pad, a second solder pad, a first layer board, a signal layer board group, and a second layer board stacked in sequence from bottom to top; The side edge of the first layer is flush with the side edge of the second layer; The signal layer board group includes two adjacent signal layer boards, each signal layer board has an extension portion, the extension portion protrudes from a side of the first layer board, and a first solder pad is provided on the extension portion; The second pads are provided on the surface of the first layer board and / or the surface of the second layer board. The first pads are electrically connected to the second pads. The first pads provided on a group of signal layer boards are used to transmit a pair of differential signals.

2. The printed circuit board according to claim 1, wherein The first layer board and / or the second layer board are provided with a conductive portion, and the conductive portion extends from the second pad along the thickness direction of the printed circuit board to the signal layer board group.

3. The printed circuit board according to claim 2, wherein: The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the conductive portion includes: a coaxially arranged conductive outer wall and a conductive inner wall, and an insulating layer is provided between the conductive outer wall and the conductive inner wall; The conductive outer wall is connected to a conductive trace of one signal layer in the signal layer board, and is used to transmit one signal in the pair of differential signals; The conductive inner wall is connected to a conductive trace of another signal layer in the signal layer, and is used to transmit the other signal in the pair of differential signals.

4. The printed circuit board according to claim 3, wherein: The conductive traces on two signal layer boards in the signal layer board group overlap in the thickness direction of the printed circuit board.

5. The printed circuit board according to claim 4, wherein: A wiring obstacle area is provided on the straight segment path between the conductive portion and the first pad; The conductive traces include: a first trace, an obstacle-avoiding trace, and a second trace; The first routing line and the second routing line are arranged along a straight line segment connecting the conductive portion and the first pad, one end of the first routing line is electrically connected to the conductive portion, the other end of the first routing line is electrically connected to one end of the obstacle bypass routing line, the other end of the obstacle bypass routing line is electrically connected to one end of the second routing line, and the other end of the second routing line is electrically connected to the first pad; The obstacle-avoiding routing line is spaced apart from the edge of the wiring obstacle area.

6. The printed circuit board according to claim 1, wherein The extension portion of the signal layer board is arranged in a stepped shape in the thickness direction of the printed circuit board.

7. The printed circuit board according to claim 6, wherein: The signal layer board group has a first middle plane, and the number of signal layer boards arranged on both sides of the first middle plane is the same; The extension portion of the signal layer board is symmetrically structured on both sides of the first middle plane.

8. The printed circuit board according to claim 7, wherein: The distance between the edge of the extension portion facing away from the side of the first layer board and the side of the first layer board decreases successively in the direction of the signal layer board adjacent to the middle plane pointing away from the first middle plane.

9. The printed circuit board according to claim 6, wherein: An edge of the extension portion facing away from the first layer board is chamfered.

10. The printed circuit board according to claim 9, wherein The printed circuit board comprises at least two groups of signal layer boards, the at least two groups of signal layer boards have a second middle plane, and the number of signal layer boards arranged on both sides of the second middle plane is the same; The chamfer of the signal layer disposed adjacent to the second intermediate plane has a first angle; The chamfers of the remaining signal layer boards are at the second angle.

11. The printed circuit board according to claim 10, wherein: The first angle is 30 to 40 degrees; The second angle is 15 degrees to 25 degrees.

12. The printed circuit board according to claim 10, wherein The wide side of the first pad is located on the plane where the corresponding signal layer is located, and is arranged along the edge of the chamfer; The first pad has a pad width; In the width direction of the pads, a preset spacing is provided between adjacent first pads; The length of the first pad of the signal board layer arranged adjacent to the second middle plane is a first length; The length of the first pads of the remaining signal layer boards is the second length.

13. The printed circuit board according to claim 12, wherein: The two signal layer boards in the signal layer board group are respectively provided with conductive traces, and the width of the first pad is W+0.1 mm to W+0.5 mm, where W represents the width of the conductive trace of the corresponding signal layer board; The first length is 2.5 mm to 3 mm; The second length is 3 mm to 3.5 mm; The preset spacing is at least 0.2 mm.

14. The printed circuit board according to claim 10, wherein: In the direction of the second middle plane, a horizontal spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

15. The printed circuit board according to claim 14, wherein: The horizontal spacing is L=Y / 1.5, wherein L represents the horizontal spacing, and Y represents the yield of machining the extension portion using a milling cutter.

16. The printed circuit board according to claim 14, wherein: The minimum value of the horizontal spacing is 0.6 mm.

17. The printed wiring board according to claim 10, wherein In a direction perpendicular to the printed circuit board, a vertical spacing is provided between the first pads on adjacent signal layer boards located on either side of the second middle plane.

18. The printed circuit board according to claim 17, wherein: The minimum value of the vertical spacing is 0.5 mm.

19. The printed circuit board according to claim 1, wherein A signal processing device is provided on the surface of the first layer board and / or the surface of the second layer board, and a pin for signal transmission in the signal processing device is electrically connected to the second pad.

20. A slot, characterized in that: The slot is adapted to fit a connector base formed by an extension of a signal layer board in the printed circuit board according to any one of claims 1 to 19; The slot includes a third solder pad. After the connector base is plugged into the slot, the third solder pad forms an electrical connection with the corresponding first solder pad.

21. A method for manufacturing a connector, characterized in that: A connector base formed by processing an extension portion of a signal layer in a printed circuit board according to any one of claims 1 to 19 to form a connector, comprising: Laminating the printed circuit board; The connector base is obtained by laser cutting the extension portion of the signal layer board, wherein the extension portion of the signal layer board is pre-set with a first solder pad; The first pad is plated with gold to obtain the connector.

22. A method for manufacturing a connector, characterized in that: A connector base formed by processing an extension portion of a signal layer in a printed circuit board according to any one of claims 1 to 19 to form a connector, comprising: Filling the extended portion of the signal layer with a gasket, and laminating the gasketed signal layer layer by layer; Using a milling cutter to remove the gaskets layer by layer to expose the extension portion of the corresponding signal layer board; peeling off the residual pad covering the surface of the extension portion of the corresponding signal layer board to expose the first pad of the corresponding signal layer board, where the first pad is preset on the extension portion of the signal layer board; The first pad is plated with gold to obtain the connector.

23. The connector manufacturing method according to claim 22, characterized in that: A baffle is provided on the milling cutter column of the milling cutter, and the baffle is used to control the cutting depth of the milling cutter.

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