WO2023019864A1

WO2023019864A1 - Printed circuit board, and wiring method for printed circuit board

Info

Publication number: WO2023019864A1
Application number: PCT/CN2021/143423
Authority: WO
Inventors: 蔡元元; 王志钢; 皮本元
Original assignee: 展讯通信（上海）有限公司
Priority date: 2021-08-16
Filing date: 2021-12-30
Publication date: 2023-02-23
Also published as: CN113473724A; CN113473724B

Abstract

The present application provides a printed circuit board, and a wiring method for the printed circuit board. The printed circuit board comprises a wiring layer and a ground plane layer that are disposed in a stacked manner; the wiring layer is provided with a first signal line; the first signal line is bent to form at least one groove region; each groove region comprises an opening and a bottom; a shielding component is provided at a first groove region in the at least one groove region; a through hole is formed in the shielding component; the through hole is located at the opening of the first groove region; and the shielding component is connected to a system ground of the ground plane layer by means of the through hole. The present application facilitates improving an electromagnetic shielding effect between serpentine signal lines of the printed circuit board, and improving the crosstalk problem of the serpentine signal lines.

Description

Printed circuit boards and printed circuit board wiring methods

technical field

The present application relates to the technical field of printed circuit boards, in particular to a printed circuit board and a wiring method for the printed circuit board.

Background technique

With the development of 5G (5th Generation Mobile Communication, fifth-generation mobile communication technology), the requirements for high-speed signal transmission are getting higher and higher. In the design of high-speed PCB (Printed Circuit Board, printed circuit board), in order to meet high-speed signal According to the timing requirements, equal-length winding of the signal is required.

At present, the serpentine routing method is usually adopted to wind the shorter signal wires in a group of signal wires within the tolerance range of the length of the longest signal wire in the group, so as to control the delay. However, there will be crosstalk problems in the part of the signal line in the serpentine trace (because the distance between the line and the line is very close, the signal on the trace can be coupled to some adjacent transmission lines through space, and this process is Called crosstalk), crosstalk will not only affect the voltage amplitude on the victim line, but also affect the transmission delay of the signal on the victim line and affect the signal quality.

Contents of the invention

The embodiments of the present application provide a printed circuit board and a wiring method for the printed circuit board, in order to improve the electromagnetic shielding effect between the serpentine signal lines of the printed circuit board and improve the crosstalk problem of the serpentine signal lines.

In a first aspect, the present application provides a printed circuit board wiring method, the printed circuit board includes a stacked wiring layer and a ground plane layer, the wiring layer is provided with a first signal line, and the first signal line is bent to form at least one recessed region, each recessed region comprising an opening and a bottom; the method comprising:

A shielding member is provided in a first recessed area of the at least one recessed area;

opening a through hole on the shielding component, the through hole is located at the opening of the first groove area;

The shielding component is connected to the system ground of the ground plane layer through the through hole.

Optionally, each groove region in the at least one groove region is the first groove region.

Optionally, the method further includes: opening the ground wire at the bottom of the first groove area.

Optionally, the shielding component is a ground wire; or, the shielding component is copper skin.

Optionally, the first signal line is a single-ended signal line; or, the first signal line is a differential signal line, the opening direction of the first groove area is away from the second signal line, and the second signal line The line is another differential signal line forming a differential signal line group with the first signal line.

In a second aspect, the present application provides a printed circuit board, the printed circuit board includes a wiring layer and a ground plane layer stacked, the wiring layer is provided with a first signal line, and the first signal line is bent to form at least one recessed regions, each recessed region comprising an opening and a bottom;

The first groove area in the at least one groove area is provided with a shielding part, and a through hole is opened on the shielding part, and the through hole is located at the opening of the first groove area, and the shielding part passes through The through hole is connected to the system ground of the ground plane layer.

It can be seen that in the embodiment of the present application, a shielding component is provided in the groove area formed by bending the serpentine signal line of the wiring layer of the printed circuit board, and a through hole is opened on the shielding component, and the through hole is located at the opening of the groove area. Then, the shielding component is connected to the system ground of the ground plane layer of the printed circuit board through the through hole, which is conducive to improving the electromagnetic shielding effect between the serpentine signal lines and improving the crosstalk problem of the serpentine signal lines.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present application. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic flow diagram of a printed circuit board wiring method provided in an embodiment of the present application;

Fig. 2 is a schematic diagram of the position of a shielding component provided by the embodiment of the present application;

FIG. 3 is a simulation diagram of a printed circuit board wiring structure provided by an embodiment of the present application;

FIG. 4 is a schematic diagram of the port voltage in the simulation diagram of the printed circuit board wiring structure provided by the embodiment of the present application;

5 is a schematic diagram of the simulation results of the printed circuit board wiring structure provided by the embodiment of the present application;

FIG. 6 is a schematic diagram of the position of another shielding component provided in the embodiment of the present application;

Fig. 7 is a schematic diagram of the position of another shielding component provided by the embodiment of the present application;

Fig. 8 is a schematic diagram of the position of another shielding component provided by the embodiment of the present application;

FIG. 9 is a schematic diagram of the position of another shielding component provided by the embodiment of the present application.

Detailed ways

In order to facilitate the understanding of the present application, and to make the above-mentioned purpose, features and advantages of the present application more obvious and understandable, the specific implementation manners of the present application will be described in detail below in conjunction with the accompanying drawings. In the following description, numerous specific details are set forth to facilitate a full understanding of the application, and preferred embodiments of the application are shown in the accompanying drawings. However, the present application can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the application more thorough and comprehensive. The present application can be implemented in many other ways that are different from those described here, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined. In the description of the present application, "several" means at least one, such as one, two, etc., unless otherwise specifically defined.

As shown in FIG. 1 , an embodiment of the present application provides a printed circuit board wiring method, the printed circuit board includes a stacked wiring layer and a ground plane layer, the wiring layer is provided with a first signal line, and the first The signal line is bent to form at least one groove area, each groove area includes an opening and a bottom; the method includes:

Step 101, disposing a shielding component in the first groove region of the at least one groove region;

Step 102, opening a through hole on the shielding component, the through hole is located at the opening of the first groove area;

Step 103, connecting the shielding component to the system ground of the ground plane layer through the through hole.

Specifically, please refer to FIG. 2. The first signal line may be a signal line that adopts a serpentine wiring method. As shown by the gray line in FIG. 2, the first signal line is bent to form at least one groove area, and each groove area is The closed end of the first signal line is the bottom of the groove area, and the end not closed by the first signal line is the opening of the groove area.

Taking the area 1 indicated in Figure 2 as the first groove area as an example, a shielding part 2 is arranged in the first groove area, and a through hole 3 is opened on the shielding part 2, and the through hole 3 is located in the first groove The opening of area 1. The shielding component 2 can be connected to the ground plane layer of the printed circuit board nearby through the through hole 3, so as to reduce the grounding path of the shielding component, further improve the electromagnetic shielding effect, and improve the crosstalk between signal lines.

Wherein, the opening manner of the through hole is not specifically limited here, and the shielding component may be connected to the ground plane layer through the through hole.

In the specific implementation, since the diameter of the through hole is usually much larger than the diameter of the signal line, and the serpentine wiring itself occupies a large space on the printed circuit board, for the sake of saving wiring space, the signal line gap of the serpentine wiring is formed by bending The width of each groove area usually does not exceed three times the line width, and sometimes the width of each gap may even take twice the line width, that is, the diameter of the through hole may exceed the width of the first groove area. At this time, The location of the through hole can specifically meet the following conditions: the maximum width of the part of the through hole falling in the first groove area does not exceed the width of the first groove area, that is, there is no need to increase the size of the through hole because of the opening of the through hole. The width of the first groove area and the opening of the through hole will not occupy too much extra wiring space on the printed circuit board.

It should be noted that the first signal line shown in Figure 2 is only to illustrate the position of the shielding component. In practical applications, the wiring structure of the first signal line is set according to its actual signal transmission requirements. The specific bending wiring method And the number of grooved areas formed by bending may be different from that shown in Figure 2; in addition, only one first grooved area is shown in Figure 2 as an example, and the number of first grooved areas in actual applications can be more For example, each groove area may be the first groove area, which is not specifically limited here.

In some possible examples, each groove region in the at least one groove region is the first groove region.

Specifically, each groove area in at least one groove area is a first groove area, that is, each groove area formed by bending the first signal line is provided with a shielding component, and a through hole is opened on each shielding component , the position of the through hole is located at the opening of each groove area, and each shielding component can be connected to the ground plane layer of the printed circuit board by opening a through hole on it, that is, each shielding component is grounded nearby, shortening Path to ground for each shielded component.

It can be seen that, in this example, each groove area in at least one groove area formed by bending the first signal line is a first groove area, that is, each groove area in which the first signal line is completely formed is provided with Each shielding component is provided with a through hole, and each shielding component is grounded nearby, which is conducive to further improving the electromagnetic shielding effect between the serpentine signal lines and improving the crosstalk problem between the signal lines.

In some possible examples, the method further includes: opening a shielding component at the bottom of the first groove region.

In the specific implementation, considering the various functions of terminals such as mobile phones, the number of electronic components per unit area of the printed circuit board in the terminal is also increasing, but the size of the terminal is limited, and the serpentine wiring itself will occupy a large area. Wiring space, and the through hole itself will occupy a large wiring space, therefore, the shielding part at the bottom of the first groove area is opened, that is, the bottom of the first groove area (or other positions inside the first groove area) is not opened Through-holes can further save space on the printed circuit board.

It can be seen that, in this example, the shielding component at the bottom of the first groove area is open, which is beneficial to improve the electromagnetic shielding effect, improve the crosstalk problem between the serpentine signal lines, and save the wiring space of the printed circuit board.

Alternatively, in other embodiments, if the printed circuit board wiring space itself is relatively sufficient, multiple through holes can be opened on the shielding component, and the positions of the through holes can be inside the first groove area, such as port 1 in Figure 3 As shown by the signal line in the middle of port 2, the location of the via can be at the bottom of the first groove area.

Specifically, three printed circuit board wiring structures are shown in FIG. 3, wherein, for the signal line a between port 1 and port 2, shielding components are provided in the multiple groove areas formed by bending the signal line a. , two through holes are opened on each shielding part, one through hole is located at the bottom of the groove area, and the other through hole is located at the opening of the groove area; for the signal line b between port 3 and port 4, the signal line b Shielding parts are provided in the multiple groove areas formed by bending, and only one through hole is opened on each shielding part. The through hole is located at the opening of the groove area, and no through hole is opened inside the groove area. The shielding part at the bottom of the groove area is open; for the signal line c between port 5 and port 6, no shielding part is provided between the signal lines.

The three wiring structures shown in Figure 3 are simulated according to the conditions shown in Figure 4, where the voltages V1, V2, and V3 at

ports

1, 3, and 5 have the same amplitude at the same time point, and R1, R2, and R3 is also the same. The signal simulation results at port 2, port 4, and port 6 are shown in Figure 5, where the black solid line is the simulation result of port 6, the black dotted line is the simulation result of port 4, and the gray solid line is the simulation result of port 2. The horizontal axis represents the signal delay of the port, the unit is nS, and the vertical axis represents the port voltage amplitude, the unit is mV. It can be seen from Figure 5 that the simulated signals at port 2 and port 4 are set in the gap between the signal lines The shielding part is used to reduce its own electromagnetic coupling, so the signal delay is basically the same, and the signal simulated at port 6 is not protected by crosstalk wiring, so the electromagnetic capabilities are partially coupled to each other, so that the signal delay is advanced Arrival, the control of signal delay failed to meet expectations.

In some possible examples, the shielding component is a ground wire; or, the shielding component is copper skin.

In a specific implementation, the conductive pattern of the shielding component can be in the form of a wire or a copper skin.

Specifically, taking at least one groove area where each groove area is the first groove area as an example, when the shielding component is a ground wire, the setting of the shielding component can be as shown in Figure 6, and the gray line in Figure 6 is The first signal line, the black line is the grounding line; when the shielding component is copper, the setting of the shielding component can be shown in FIG. 7 . In Figure 7, the black line is the first signal line, and the shaded part is the copper skin.

In practical applications, the width of the grounding wire can be selected and set according to the needs. The shielding part shown in Figure 6 is only for describing the position of the shielding part. The width of the shielding part can be selected according to the needs. Specifically, the value of the shielding part width It can be set as large as possible while satisfying the safety gap of the conductive pattern.

It can be seen that in this example, the shielding component may be a ground wire or a copper sheet, that is, the form of the shielding component may be flexibly selected.

In some possible examples, the first signal line is a single-ended signal line; or, the first signal line is a differential signal line, and the opening direction of the first groove area is away from the second signal line, the The second signal line is another differential signal line forming a differential signal line group with the first signal line.

Wherein, the single-ended signal line may be a single-ended high-speed signal line, and the differential signal line may be a differential high-speed signal line for transmitting high-speed digital signals.

Wherein, at least one groove area formed by bending the second signal line may also include a first groove area, and the opening direction of the first groove area is away from the first signal line.

Specifically, referring to FIG. 8 and FIG. 9, in at least one groove area formed by bending the first signal line, each groove area whose opening direction is away from the second signal line can be the first groove area. Among the at least one groove area formed by bending the two signal lines, each groove area whose opening direction is away from the first signal line may be the first groove area. Among them, the shielding part is shown in the form of a ground wire in Figure 8, the gray line in Figure 8 is the first signal line and the second signal line, and the black line is the ground wire; Figure 9 shows the shielding part in the form of a copper sheet Components, the black line in Figure 9 is the first signal line and the second signal line, and the shaded part is the copper skin.

It can be seen that, in this example, the first signal line may be a single-ended signal line or a differential high-speed signal line, that is, this method may be applied to various types of signal lines to improve crosstalk between signal lines.

The embodiment of the present application also provides a printed circuit board, the printed circuit board includes a wiring layer and a ground plane layer stacked, the wiring layer is provided with a first signal line, and the first signal line is bent to form at least one concave Groove areas, each groove area includes an opening and a bottom; the first groove area in the at least one groove area is provided with a shielding component, and a through hole is opened on the shielding component, and the through hole is located in the first groove area. At an opening of a groove area, the shielding component is connected to the system ground of the ground plane layer through the through hole.

In some possible examples, the shielding component at the bottom of the first groove area is open.

The above examples only express several implementation modes of the present application, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of protection of the patent application should be based on the appended claims.

Claims

A printed circuit board wiring method, characterized in that the printed circuit board includes a stacked wiring layer and a ground plane layer, the wiring layer is provided with a first signal line, and the first signal line is bent to form at least one concave groove regions, each groove region comprising an opening and a bottom; the method comprising:

A shielding member is provided in a first recessed area of the at least one recessed area;

opening a through hole on the shielding component, the through hole is located at the opening of the first groove area;

The shielding component is connected to the system ground of the ground plane layer through the through hole.
The printed circuit board wiring method according to claim 1, wherein each of the at least one groove area is the first groove area.
The printed circuit board wiring method according to claim 1, wherein the method further comprises:

Open the ground wire at the bottom of the first groove area.
The method for wiring a printed circuit board according to claim 1, wherein the shielding component is a ground wire; or, the shielding component is a copper sheet.
The printed circuit board wiring method according to claim 1, wherein the first signal line is a single-ended signal line; or, the first signal line is a differential signal line, and the first groove area The opening direction is away from the second signal line, and the second signal line is another differential signal line forming a differential signal line group with the first signal line.
The method for wiring a printed circuit board according to claim 1, wherein the first signal line is a signal line using snake letter wiring.
The method for wiring a printed circuit board according to claim 1, wherein the opening position of the through hole satisfies the following condition: the maximum width of the part of the through hole falling in the first groove area does not exceed the specified The width of the first groove area.
The method for wiring a printed circuit board according to claim 5, wherein the single-ended signal line is a single-ended high-speed signal line.
The printed circuit board wiring method according to claim 5, wherein the differential signal line is a differential high-speed signal line.
The printed circuit board wiring method according to claim 5, wherein at least one groove area formed by bending the second signal line includes the first groove area, and the groove area formed by bending the second signal line The opening direction of the first groove area is away from the first signal line.
A printed circuit board, characterized in that the printed circuit board includes a wiring layer and a ground plane layer stacked, the wiring layer is provided with a first signal line, and the first signal line is bent to form at least one groove area , each groove area includes an opening and a bottom;

The first groove area in the at least one groove area is provided with a shielding part, and a through hole is opened on the shielding part, and the through hole is located at the opening of the first groove area, and the shielding part passes through The through hole is connected to the system ground of the ground plane layer.
The printed circuit board according to claim 11, wherein each of the at least one recessed area is the first recessed area.
The printed circuit board according to claim 11, wherein the shielding part at the bottom of the first groove area is open.
The printed circuit board according to claim 11, wherein the shielding component is a ground wire; or, the shielding component is copper skin.
The printed circuit board according to claim 11, wherein the first signal line is a single-ended signal line; or, the first signal line is a differential signal line, and the opening direction of the first groove area Away from the second signal line, the second signal line is another differential signal line forming a differential signal line group with the first signal line.
The printed circuit board according to claim 11, characterized in that, the first signal line is a signal line adopting snake letter wiring.
The printed circuit board according to claim 11, wherein the opening position of the through hole satisfies the following condition: the maximum width of the part of the through hole falling in the region of the first groove does not exceed the first groove. The width of a notch area.
The printed circuit board according to claim 15, wherein the single-ended signal line is a single-ended high-speed signal line.
The printed circuit board according to claim 15, wherein the differential signal line is a differential high-speed signal line.
The printed circuit board according to claim 15, wherein the second signal line is bent to form at least one groove area including the first groove area, and the second signal line is bent to form the first groove area. The opening direction of the groove area is away from the first signal line.