CN2527062Y - Wiring structure of circuit board signal transmission line - Google Patents

Abstract

A wiring structure for signal transmission lines of a circuit board, characterized in that at least one pair of two differential signal transmission lines in the circuit board are wired in two adjacent layers among several different layers of the circuit board, wherein one of the two transmission lines is wired in a signal transmission layer, and the other of the two transmission lines is wired in a power supply layer or a grounding layer, and a better transmission effect can be achieved when the spacing between the two adjacent layers is at a certain specific value. The number of layers of the circuit board at least includes a signal layer, a power supply layer and a grounding layer.

Description

Wiring structure of circuit board signal transmission line

technical field

The utility model relates to a wiring structure of a signal transmission line of a circuit board, in particular to a wiring structure of a specific layer and a specific distance of a high-frequency signal transmission line in a multilayer circuit board in a high-frequency circuit.

Background technique

In the printed circuit board used in general high-frequency wireless communication, due to the extremely high frequency used, the configuration of each component in the circuit board and the design of related circuit wiring must be strictly designed and arranged to avoid circuit High-frequency effects or other adverse effects will affect the electrical characteristics of the entire circuit, especially the popular Personal Digital Assistant (PDA) and very common mobile phones and other high-frequency communication electronic products. The transmission performance and anti-noise ability requirements are higher.

On general circuit boards or main boards, in addition to the general wiring design for signal transmission or power supply, special attention and consideration are usually paid to the setting of signal transmission lines (trace), because whether the design of the transmission line is good or not is related to the entire circuit. Communication transmission characteristics, of course, also affect the communication quality of communication products, and are directly related to whether the product can be accepted by consumers. These characteristics are, for example, the matching of the transmission performance of the circuit board and the characteristic impedance, and the ability of the signal to resist noise. etc.

Please refer to Figure 1, which is a schematic diagram of the wiring of the existing circuit board transmission lines. As shown in Figure 1, a circuit board 1 is a multilayer structure, wherein the wiring design of the multilayer structure is related to the characteristics and circuit complexity of the overall circuit, and the first layer 15 in the circuit board 1 It is a signal transmission layer, and signal transmission lines 151 and 152 are usually arranged on the signal transmission layer, wherein the signal transmission lines 151 and 152 are a pair of differential signal transmission lines, and the individual wiring length and width of the two signal lines and the distance from each other W1 is related to the characteristic impedance and related characteristics of the signal line. The distance between the transmission lines 151 and 152 is maintained at about 5 mils due to the limitation of the overall manufacturing process of the circuit board. However, generally speaking, two pairs of differential signals The smaller the distance between the lines, the better the transmission quality and efficiency, and the ability to eliminate noise, such as eliminating electromagnetic interference (EMI). A method is used to overcome the shortcoming that the distance between two transmission lines cannot be reduced in the prior art.

Utility model content

The main purpose of the utility model is to provide a wiring structure of circuit board signal transmission lines to improve the transmission efficiency of transmission line signals and reduce noise interference, and to reduce the distance between paired transmission lines and achieve better transmission effects.

In order to achieve the above object, the wiring structure of the circuit board signal transmission line of the present invention is characterized in that at least one pair of paired two differential signal transmission lines in the circuit board are wired on two of the several different layers of the circuit board. Adjacent layers, wherein one of the two transmission lines is routed in a signal transmission layer, and the other of the two transmission lines is routed in a non-signal transmission layer.

The number of layers of the circuit board includes at least a signal layer, a power layer and a ground layer.

In order to more clearly connect the purpose, features and advantages of the utility model, preferred embodiments of the utility model will be described in detail below in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a schematic diagram of the design of test lines in an existing circuit board.

Fig. 2 is a schematic diagram of a first preferred embodiment of the utility model applied to a multi-layer circuit board.

Fig. 3 is a schematic diagram of a second preferred embodiment of the utility model applied to a multi-layer circuit board.

Fig. 4 is a schematic diagram of a third preferred embodiment of the utility model applied to a multi-layer circuit board.

Fig. 5 is a schematic diagram of a fourth preferred embodiment of the utility model applied to a multi-layer circuit board.

Detailed ways

The utility model discloses a wiring structure of a circuit board signal transmission line applied to a high-frequency circuit. It is for wiring two pairs of differential signal transmission lines on two adjacent layers of the circuit board, wherein one of the two transmission lines is wired on the signal layer, and the other is routed to a power layer or a ground layer.

Please refer to FIG. 2 , which shows a first preferred embodiment of the utility model applied to a multilayer circuit board. As shown in Figure 2, the multilayer circuit board 2 can be applied in the circuit board of high-frequency communication, wherein two signal transmission lines can be designed in two adjacent layers such as the third layer 23 and the fourth layer 24, and they are in phase Corresponding arrangement, wherein the transmission line 231 on the third layer 23 and the transmission line 241 on the fourth layer 24 transmit a pair of differential signals, the two signals are in fact the same signal and become two signals after a phase shift. The purpose of transmission is to prevent the signal from being interfered during the transmission process. In addition, the relative vertical distance between the transmission line 231 and the transmission line 241 must be limited in order to obtain good results in transmission quality and performance. In the actual circuit where the utility model is applied, the relative distance W2 between the transmission line 231 and the transmission line 241 can be regulated between 2.5-4 mils (mil). Moore (mil) when the effect is better.

In addition, in the circuit wiring design of a multi-layer circuit board, the signal layer or the power layer or the ground layer may have several layers respectively, and the number of layers and the position in the circuit board are related to the characteristics of the circuit or the desired It is related to the relevant design of the function, and also related to the complexity of the circuit and the ability of the designer. In the application of the utility model, it is the design of which layer should be designed for the better signal transmission line.

Please refer to FIG. 3 , which is a schematic diagram showing a second preferred embodiment of the utility model applied to a multilayer circuit board. As shown in Figure 3, the circuit board is a six-layer structure (L1-L6), wherein the first layer 31, the third layer 33, and the sixth layer 36 are the signal transmission layer (S), the second layer 32, the fifth layer Layer 35 is the ground layer (GND), the fourth layer 34 is the power supply layer Vcc, and the second layer 32 and the third layer 33 are respectively wired with transmission lines 321, 331, which are respectively wired on the second layer 32 (ground layer) And the third layer 33 (signal transmission layer) can prevent signal transmission from being interfered by noise during transmission to ensure better communication quality.

Please refer to FIG. 4 , which is a schematic view showing a third preferred embodiment of the present invention applied to a multilayer circuit board. As shown in Figure 4, this circuit board is also a six-layer structure (L1～L6), wherein the first layer 41, the third layer 43, the sixth layer 46 are the signal transmission layer (S), the second layer 42, the sixth layer The fifth layer 45 is the ground layer (GND), the fourth layer 44 is the power layer (Vcc), and the third layer 43 and the fourth layer 44 are respectively wired with transmission lines 431, 441, which are respectively wired on the third layer 43 ( The signal transmission layer) and the fourth layer 44 (power supply layer) can prevent the signal transmission from being interfered by noise during the transmission process to ensure the signal transmission quality and the overall circuit characteristics and performance.

Please refer to FIG. 5 , which is a schematic diagram showing a fourth preferred embodiment of the utility model applied to a multilayer circuit board. As shown in Figure 5, this circuit board is also a six-layer structure (L1～L6), wherein the first layer 51, the third layer 53, the sixth layer 56 are the signal transmission layer (S), the second layer 52, the sixth layer The fifth layer 55 is a ground layer (GND), and the fourth layer 54 is a power layer (Vcc). The third layer 53 (signal transmission layer) and the fourth layer 54 (power layer) are respectively wired with transmission lines 531 and 541 . In addition, the fifth layer 55 (ground layer) and the sixth layer 56 (signal transmission layer) are respectively wired with transmission lines 551 and 561 . This design method allows several pairs of differential signal transmission lines to be designed and wired between several different layers in a multi-layer structure in a circuit board. For example, although the number of layers is different in a six-layer circuit board and an eight-layer circuit board, but Such a design method can be applied to a more complex circuit with several groups of different transmission signals at the same time.

Through the arrangement of one or more pairs of differential signal transmission lines described in the above-mentioned preferred embodiments, and the design at certain levels can be designed according to the needs of the actual circuit, and it is not due to the implementation of multi-layer The total number of layers of the circuit board is different, for example, an eight-layer circuit board or a circuit board with more layers is also applicable to the technology proposed by the utility model. The design of the utility model can improve the efficiency of signal transmission, reduce the situation of signal interference, and improve the existing technology that cannot reduce the distance between two transmission lines.

The above descriptions are only preferred embodiments of the present utility model, but cannot be used to limit the implementation scope of the present utility model. Various equivalent changes and equivalent replacements made according to the spirit of the utility model should still fall within the scope covered by the utility model patent.

Claims (10)

1. A wiring structure of a circuit board signal transmission line, characterized in that, at least one pair of paired two differential signal transmission lines in the circuit board are wired on two adjacent layers in several different layers of the circuit board, wherein One of the two transmission lines is wired in a signal transmission layer, and the other of the two transmission lines is wired in a non-signal transmission layer. 2 . The wiring structure of signal transmission lines of a circuit board according to claim 1 , wherein the circuit board at least comprises a signal layer, a power layer and a ground layer. 3 . 3 . The wiring structure of the signal transmission line of the circuit board according to claim 1 , wherein the distance between the two adjacent layers is between 2.5-4 mils. 4 . 4. The wiring structure of the circuit board signal transmission line according to claim 1, wherein the distance between the two adjacent layers is 3 mils. 5. The wiring structure of the signal transmission line of the circuit board according to claim 1, wherein the two adjacent layers are a signal transmission layer and a power supply layer. 6. The wiring structure of signal transmission lines of a circuit board according to claim 1, wherein the two adjacent layers are a signal transmission layer and a ground layer. 7. The wiring structure of circuit board signal transmission lines according to claim 1, wherein said circuit board is a six-layer circuit board. 8. The wiring structure of circuit board signal transmission lines according to claim 1, wherein said circuit board is an eight-layer circuit board. 9. The wiring structure of circuit board signal transmission lines according to claim 1, wherein said circuit board is used for a high-frequency wireless communication circuit. 10. The wiring structure of circuit board signal transmission lines according to claim 1, wherein said circuit board is used in personal digital assistant products.

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