CN104244574A - Pcb signal wiring structure and electronic product interface - Google Patents

Abstract

The present invention provides a PCB signal wiring structure and an electronic product interface, wherein the PCB signal wiring structure comprises a PCB with at least four layers of board structure, wherein each four layers form a differential signal routing unit; each of the differential signal routing units comprises a top layer and a bottom layer, and two adjacent middle layers arranged between the top layer and the bottom layer; the top layer and the bottom layer are both differential signal reference plane layers, and the two middle layers are both differential signal routing layers; one of the two differential signal routing layers is arranged with a positive signal line, and the other layer is correspondingly arranged with a negative signal line. The positive signal line and the negative signal line of the differential signal are arranged on the two adjacent layers respectively, and the differential signal routing is also realized. In this way, multiple groups of differential pair signal routing can be realized in a narrower PCB area.

Description

PCB signal wiring structure and electronic product interface

technical field

The invention relates to PCB design technology, in particular to a PCB signal wiring structure and an electronic product interface.

Background technique

With the rapid development of electronic products, product personalization is promoted. Make the internal structural space of the product more compact and narrow, so that the PCB board area of the product will also become smaller and narrower. The LVDS interface and MIPI interface that are trendingly used in digital products are composed of multiple sets of differential pair signals. When multiple sets of differential signals travel on the same layer, a larger PCB area is required, which will have a great impact on the internal structure design of the product, and even affect the realizability of the product design.

Contents of the invention

Based on this, the present invention proposes a PCB signal wiring structure and an electronic product interface to solve the problem that the multiple sets of differential signal lines require a large area and affect the internal structure of the product.

The present invention proposes a PCB signal wiring structure, and its technical scheme is as follows:

A PCB signal wiring structure, comprising a PCB with at least four layers of board structure, wherein every four layers are formed as a differential signal routing unit; each of the differential signal routing units includes a top layer and a bottom layer, and is arranged on the top layer and the bottom layer Two adjacent intermediate layers between the bottom layer; the top layer and the bottom layer are differential signal reference plane layers, and the two intermediate layers are differential signal routing layers; the two differential signal routing layers, wherein A positive signal line is arranged on one layer, and a negative signal line is correspondingly arranged on the other layer.

By setting the differential signal wiring layer in one layer in the prior art, that is, setting the positive signal line and the negative signal line of the differential signal on the same layer, the differential signal wiring layer is set to two layers instead, and the differential The positive signal line and the negative signal line of the signal are distributed and arranged on the two adjacent layers, and the differential signal routing is also realized. In this way, multiple sets of differential pair signal traces can be implemented in a narrow PCB area.

Its further technical scheme is described below:

Preferably, each of the differential signal routing units includes at least one pair of differential signal wires, and each pair of differential signal wires includes a positive signal wire disposed on one differential signal routing layer, and a positive signal wire disposed on another differential signal routing layer. negative signal line. That is to say, the positive signal line and the negative signal line of a pair of differential signal lines originally arranged on the same layer are respectively arranged in the two middle layers of the differential signal wiring layer, which can reduce the width of the originally required PCB wiring area by half .

Preferably, a plurality of positive signal lines and/or negative signal lines are arranged on one of the differential signal wiring layers, and a plurality of negative signal lines and/or positive signal lines are correspondingly arranged on the other differential signal wiring layer lines, each of the positive signal lines corresponds to a negative signal line. A positive signal line on one differential signal wiring layer and a corresponding negative signal line on another differential signal wiring layer form a pair of differential signal lines, thereby forming multiple pairs of differential signal lines.

Preferably, the positive signal line and the negative signal line of each pair of differential signal lines are parallel to each other, have equal length and equal width, and overlap in adjacent layers. According to the characteristics of the differential signal lines, positive signal lines and corresponding negative signal lines are arranged on adjacent differential signal wiring layers.

The present invention also proposes an electronic product interface, including the above-mentioned PCB signal wiring structure. The above-mentioned PCB signal wiring structure is applied to the interface of electronic products, so that when there are multiple pairs of differential signal lines in the product interface, the width of the interface will not be too wide, which will affect the realization of the product structure.

Its further technical scheme is described below:

Preferably, the electronic product interface includes an LVDS interface or/and a MIPI interface. The above-mentioned PCB signal wiring structure can be applied to the LVDS interface or/and MIPI interface, and in the case of multiple pairs of differential signal lines, the signal wiring of the LVDS interface and the MIPI interface can also be normally implemented.

The present invention has the following outstanding beneficial effects:

1. It is not limited to arranging differential signal lines on one PCB layer to improve PCB design flexibility;

2. Arrange the positive signal line and the negative signal line of the differential signal line on the two layers of PCB respectively to narrow the wiring area of the multi-layer PCB;

3. It is conducive to the realization of product structure design, and the product structure will not be unable to be realized normally due to too many differential signal lines.

Description of drawings

Fig. 1 is a schematic diagram when a pair of differential signal lines are arranged in the PCB signal wiring structure described in the embodiment of the present invention;

Fig. 2 is a schematic diagram when multiple pairs of differential signal lines are arranged in the PCB signal wiring structure in the embodiment of the present invention;

FIG. 3 is a schematic diagram of a PCB signal wiring structure in the prior art.

Explanation of reference numerals: (100, 100a) - differential signal reference plane layer, (110, 110a) - top layer, (120, 120a) - bottom layer, (200, 200a) - differential signal routing layer, (210, 220) - Middle layer, (212, 212a, 214)-positive signal line (or negative signal line), (222, 222a, 224)-negative signal line (or positive signal line).

Detailed ways

Embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in FIGS. 1 to 2 , a PCB signal wiring structure includes a PCB with at least four layers, wherein every four layers is formed as a differential signal routing unit. Each differential signal routing unit includes a top layer 110 and a bottom layer 120 , and two adjacent middle layers ( 210 , 220 ) disposed between the top layer 110 and the bottom layer 120 . Both the top layer 110 and the bottom layer 120 are differential signal reference plane layers 100, and the two middle layers (210, 220) are both differential signal routing layers 200; two differential signal routing layers 200, one of which is arranged with positive signal lines (212, 214), and the other layer is correspondingly arranged with negative signal lines (222, 224).

As shown in FIG. 3 , by setting the differential signal wiring layer 200a (set between the top layer 110a and the bottom layer 120a ) in the prior art in one layer, that is, the positive signal line 212a and the negative signal line 222a of the differential signal are set On the same layer, instead set the differential signal wiring layer 200 into two layers, and arrange the positive signal lines (212, 214) and negative signal lines (222, 224) of the differential signals on the two adjacent layers respectively , also implement differential signal routing. In this way, multiple sets of differential pair signal traces can be implemented in a narrow PCB area.

Specifically, each differential signal wiring unit includes at least one pair of differential signal lines, and each pair of differential signal lines includes a positive signal line (212, 214) arranged on one differential signal wiring layer 200, and a positive signal line (212, 214) arranged on another differential signal wiring layer. Negative signal lines ( 222 , 224 ) of the wiring layer 200 . That is to say, the positive signal line and the negative signal line of a pair of differential signal lines originally arranged on the same layer are correspondingly arranged in the two middle layers (210, 220) of the differential signal wiring layer, so that the original required PCB wiring area can be reduced The width is reduced by half.

Furthermore, a plurality of positive signal lines (212, 214) and/or negative signal lines (222, 224) are arranged on one differential signal wiring layer 200, and correspondingly provided on the other differential signal wiring layer 200 are A plurality of negative signal lines (222, 224) and/or positive signal lines (212, 214), each positive signal line corresponds to a negative signal line. That is, a plurality of signal lines can be arranged on one layer of differential signal wiring layer 200, and these signal lines arranged on one layer can all be positive signal lines (or negative signal lines), or can be a combination of positive signal lines and negative signal lines. Mixing; then a plurality of negative signal lines (or positive signal lines) are correspondingly arranged on another layer of differential signal wiring layer 200 , which may also be negative signal lines or positive signal lines. In short, a positive signal line on one differential signal wiring layer and a corresponding negative signal line on another differential signal wiring layer form a pair of differential signal lines, thereby forming multiple pairs of differential signal lines. The layout of multiple pairs of differential signal lines is implemented on the differential signal wiring layer.

Moreover, according to the characteristics of the differential signal lines, the positive signal lines (212, 214) and the negative signal lines (222, 224) of each pair of differential signal lines are parallel to each other, equal in length and width, and adjacent layers overlap. That is, positive signal lines and corresponding negative signal lines are arranged on adjacent differential signal wiring layers.

The present invention also proposes an electronic product interface, including the above-mentioned PCB signal wiring structure. The above-mentioned PCB signal wiring structure is applied to the interface of electronic products, so that when there are multiple pairs of differential signal lines in the product interface, the width of the interface will not be too wide, which will affect the realization of the product structure.

Specifically, the above-mentioned PCB signal wiring structure can also be applied to the LVDS interface or/and MIPI interface, and in the case of multiple pairs of differential signal lines, the signal wiring of the LVDS interface and the MIPI interface can also be normally implemented. In addition, it can also be applied to interfaces of other electronic products, or other similar PCB structures.

In this embodiment, according to the characteristics of the differential signal, the positive signal line and the negative signal line of the differential pair are respectively routed in two adjacent differential signal routing layers. According to the routing rules of the differential signal, the positive signal line of the differential pair It overlaps with the adjacent layer of the negative signal line and runs parallel to each other. Signal routing similar to LVDS interface and MIPI interface composed of multiple sets of differential pairs can be realized in a narrow PCB area. In this way, the flexibility of PCB design can be improved, and the wiring area of multilayer PCB can be narrowed, so that the shape of PCB can be designed to be narrower, which is beneficial to the realization of product structure design.

The above-mentioned embodiments only express the specific implementation manner of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims (6)

1. A PCB signal wiring structure, is characterized in that, comprises the PCB of at least four-layer board structure, wherein every four layers is formed as a differential signal routing unit; Each of the differential signal routing units includes a top layer and a bottom layer, and two adjacent intermediate layers arranged between the top layer and the bottom layer; the top layer and the bottom layer are both differential signal reference plane layers, and the two The middle layer is a differential signal wiring layer; Of the two differential signal routing layers, one layer is arranged with positive signal lines, and the other layer is correspondingly arranged with negative signal lines. 2. The PCB signal wiring structure according to claim 1, wherein each said differential signal wiring unit comprises at least one pair of differential signal lines, and each pair of differential signal lines includes a differential signal wiring layer arranged on A positive signal line, and a negative signal line arranged on another differential signal wiring layer. 3. The PCB signal wiring structure according to claim 2, wherein a plurality of positive signal lines and/or negative signal lines are arranged on one of the differential signal wiring layers, and a plurality of positive signal lines and/or negative signal lines are arranged on the other differential signal wiring layer. A plurality of negative signal lines and/or positive signal lines are correspondingly arranged on each layer, and each positive signal line corresponds to one negative signal line. 4. The PCB signal wiring structure according to any one of claims 1-3, wherein the positive signal lines and the negative signal lines of each pair of differential signal lines are parallel to each other, equal in length and equal in width, and adjacent layers overlap . 5. An electronic product interface, characterized in that it comprises the PCB signal wiring structure according to any one of claims 1-4. 6. The electronic product interface according to claim 5, wherein the electronic product interface comprises an LVDS interface or/and a MIPI interface.