TWI407849B - Printed circuit board having high-speed differential signal layout configuration - Google Patents

Abstract

A printed circuit board having high-speed differential signal layout configuration includes a high-speed differential signal control chip, coupling capacitor pads, connector pads, inductor pads, transmitting lines, sharing pads, and selecting pads. A coupling capacitor is capable of being selectively jointed between a first coupling capacitor pad and a sharing pad, and between a second coupling capacitor pad and the sharing pad. A first inductor pad and a second inductor pad are selectively jointed two inductors and not jointed any inductor.

Description

Printed circuit board with high-speed differential signal wiring structure

The present invention relates to a printed circuit board having a high speed differential signal wiring structure.

On the conventional personal computer motherboard, in addition to the central processing unit and the chipset, there are a plurality of connectors for installing the interface card. With the development of the electronics industry, the functions of the chip are further improved, and the same chip can support different connectors. For example, a Peripheral Component Interconnection (PCI) chip can support the connector of the first specification, for example, support SAS ( Serial Attached SCSI) A hard disk that transmits specifications. It can also support connectors of the second specification, such as hard disks that support SATA (Serial ATA) transmission specifications. Different motherboard products will choose to install different connectors. If some manufacturers require only the first connector on the motherboard, some manufacturers require the second connector on the motherboard. In addition, for different motherboard products, there are some special inductors (such as Ferrite Bead, ferrite beads) connected to a power supply to improve signal quality, while others do not need to connect special inductors to a power supply. .

Therefore, even if the chip can support two types of connectors, it is only produced during production. It is possible to select a type of production, that is, a motherboard that supports the connector of the first specification or a motherboard that supports the connector of the second specification, and the two cannot be shared. Therefore, according to different manufacturers' requirements, it is necessary to redesign the motherboard layout, which increases the cost of the motherboard design. Therefore, how to provide a printed circuit board and support a variety of connectors by using the same motherboard wiring has become an urgent problem to be solved in the industry.

In view of the above, it is necessary to provide a printed circuit board having a high-speed differential signal wiring structure for selectively connecting a plurality of connectors.

A printed circuit board having a high-speed differential signal wiring structure includes a high-speed differential signal control chip, first to fourth coupling capacitor pads, first and second connector pads, first and second inductor pads, and two a first transmission line, two second transmission lines, two third transmission lines, two fourth transmission lines, and a power supply pin for connecting a power source, the high-speed differential signal control chip, the first and fourth transmission lines, and the first and second induction welding The disk and the power pin are all disposed on the first layer of the printed circuit board, and the second and third transmission lines, the first to fourth coupling capacitor pads, the first and second connector pads are all disposed on the printed circuit a second layer of the board, one ends of the two second transmission lines are respectively connected to the first connector pads, and the other ends are respectively connected to the first and second coupling capacitor pads, and one ends of the two third transmission lines respectively The second connector pads are connected, and the other ends are respectively connected to the third and fourth coupling capacitor pads, and one ends of the two fourth transmission lines are respectively connected to the power pin, and the other ends are respectively connected to the first and second inductors. Pad connection The printed circuit board of the second layer between the first pad and the third coupling capacitor and said second and fourth pads also coupling capacitance pads respectively provided with two common, the two first pass One end of the transmission line is respectively connected to the output end of the high-speed differential signal control chip, and the other end is respectively connected to two selection pads disposed on the first layer of the printed circuit board, and the two common pads respectively pass through the two via holes and the two selections a pad is connected, and the two coupling capacitors are selectively soldered between the first and second coupling capacitor pads and the two common pads and between the third and fourth coupling capacitor pads and the two common pads. Two inductors or nulls can be soldered between the first and second inductor pads and the two select pads.

Compared with the prior art, the printed circuit board is provided with a common pad and a selection pad through which a coupling capacitor can be selectively connected to selectively connect different types of connectors. Through the selection pad, the inductor can be selectively mounted to connect the high-speed differential signal control chip to the power supply through the inductor, thereby improving the signal quality. In this way, by simply providing the motherboard wiring structure, it is possible to flexibly support different connectors and improve the signal quality as needed, thereby saving the cost of the motherboard design.

100‧‧‧Printed circuit board

10‧‧‧High speed differential signal control chip

20-50‧‧‧Coupling Capacitor

60‧‧‧First connector pad

70‧‧‧Second connector pad

80‧‧‧First Inductor Pad

90‧‧‧second inductor pad

12, 14‧‧‧ shared pads

15, 16‧‧‧ Via

17, 18‧‧‧Selecting the pad

102, 104, 202, 204, 302, 304, 402, 404‧‧‧ transmission lines

Vcc‧‧‧ power pin

200‧‧‧First coupling capacitor

300‧‧‧Inductance

400‧‧‧Second coupling capacitor

1 is a schematic view of a preferred embodiment of a printed circuit board having a high speed differential signal wiring structure of the present invention.

2 is a schematic view showing the wiring connection of the printed circuit board of FIG. 1.

3 is a schematic view of the printed circuit board of FIG. 1 connected only to the first connector.

4 is a schematic diagram of the printed circuit board of FIG. 1 simultaneously connecting the inductor and the first connector.

Figure 5 is a schematic view of the printed circuit board of Figure 1 connected only to the second connector.

FIG. 6 is a schematic diagram of the printed circuit board of FIG. 1 simultaneously connecting the inductor and the second connector.

Referring to FIG. 1 and FIG. 2 together, a preferred embodiment of the printed circuit board 100 having the high-speed differential signal wiring structure of the present invention includes a high-speed differential signal control chip 10 disposed on the lower layer of the printed circuit board 100, first to fourth. Coupling capacitor pads 20-50, first and second connector pads 60 and 70, first and second inductive pads 80 and 90, transmission lines 102, 104, 202, 204, 302, 304, 402, and 404, A power supply pin Vcc. The high-speed differential signal control chip 10, the transmission lines 102, 104, 402, and 404, the first and second inductance pads 80 and 90, and the power supply pin Vcc are all disposed on the lower layer of the printed circuit board, and the transmission lines 202 and 204 are disposed. , 302 and 304, first to fourth coupling capacitor pads 20-50, first and second connector pads 60 and 70 are respectively disposed on the upper layer of the printed circuit board, where the upper layer and the lower layer are relatively opposite. There is no actual difference. The first and second connector pads 60 and 70 are connector pads of the same or different specifications for mounting the same or different connectors.

One ends of the two transmission lines 202 and 204 are respectively connected to the two input ends of the first connector pad 60, and the other ends are connected to the first and second coupling capacitor pads 20 and 30, respectively. One ends of the two transmission lines 302 and 304 are respectively connected to the two input ends of the second connector pad 70, and the other ends are connected to the third and fourth coupling capacitor pads 40 and 50, respectively. One ends of the two transmission lines 402 and 404 are respectively connected to a power supply pin Vcc (which is connected to a power source such as a 1.2V DC power supply, not shown), and the other end is connected to the first and second inductance pads 80 and 90, respectively. The upper layer of the printed circuit board 100 is further provided with two common pads 12 and 14 between the first and third coupling capacitor pads 20 and 40 and between the second and fourth coupling capacitor pads 30 and 50, respectively. . One ends of the two transmission lines 102 and 104 are respectively connected to the high speed differential The signal controls the output of the wafer 10, and the other end is connected to the two selection pads 17 and 18, respectively. The two common pads 12 and 14 are respectively connected to the selection pads 17 and 18 provided on the lower layer of the printed circuit board 100 through two via holes (generally designed by blind and buried via HDI processes) 15 and 16. In other embodiments, the high speed differential signal control chip 10, the first to fourth coupling capacitor pads 20-50, the first and second connector pads 60 and 70, and the first and second inductor pads 80 and The position of the 90 on the printed circuit board 100 can also be set accordingly according to actual needs.

Referring to FIG. 3, when a first connector (not shown) needs to be mounted on the first connector pad 60 and the high-speed differential signal control chip 10 does not need to improve the signal quality, the first and second inductors are used. The pads 80 and 90 are connected to the selection pads 17 and 18, and the first coupling capacitors 200 are soldered between the first coupling capacitor pad 20 and the common pad 12 and soldered to the second coupling capacitor pad. The third and fourth coupling capacitor pads 40 and 50 are connected to each other between the shared pads 14. Thus, when the high-speed differential signal control chip 10 transmits the high-speed differential signal, the transmission through the transmission lines 102 and 104, through the selection pads 17 and 18, through the holes 15 and 16, through the common pads 12 and 14, through the first coupling The capacitor 200 is transmitted to the first connector on the first connector pad 60 via the transmission lines 202 and 204 via the first and second coupling capacitor pads 20 and 30.

Referring to FIG. 4, when a first connector (not shown) needs to be mounted on the first connector pad 60 and the high-speed differential signal control chip 10 needs to improve the signal quality, the first and second inductors are used. Solder two inductors 300 (such as Ferrite Bead, ferrite bead) between pads 80 and 90 and select pads 17 and 18, respectively, and solder two first coupling capacitors (usually AC coupling capacitors) 200 to the first A coupling capacitor pad 20 and the common pad 12 are soldered between the second coupling capacitor pad 30 and the common pad 14, and the third and fourth coupling capacitor pads 40 and 50 are connected to each other. Thus, when the high-speed differential signal control chip 10 transmits the high-speed differential signal, the transmission through the transmission lines 102 and 104, through the selection pads 17 and 18, through the holes 15 and 16, through the common pads 12 and 14, through the first coupling The capacitor 200 is transmitted to the first connector on the first connector pad 60 via the transmission lines 202 and 204 via the first and second coupling capacitor pads 20 and 30, and the wafer 10 is transmitted through the transmission line due to the high-speed differential signal. 102 and 104, through the selection of the pads 17 and 18, through the inductor 300, through the first and second inductor pads 80 and 90, via the transmission lines 402 and 404, the power supply is connected via the power pin Vcc, Effectively improve signal quality.

Referring to FIG. 5, when a second connector (not shown) needs to be mounted on the second connector pad 70 and the high-speed differential signal control chip 10 does not need to improve the signal quality, the first and second inductors are used. The pads 80 and 90 are connected to the selection pads 17 and 18, and the second coupling capacitors 400 are soldered between the third coupling capacitor pad 40 and the common pad 12 and soldered to the fourth coupling capacitor pad. 50 and the common pad 14 , and the first and second coupling capacitor pads 20 and 30 are vacant. Thus, the high speed differential signal control chip 10 transmits the high speed differential signal through the transmission lines 102 and 104, then through the selection pads 17 and 18, through the holes 15 and 16, through the common pads 12 and 14, via the second coupling. The capacitor 400 is transmitted via the transmission lines 302 and 304 to the second connector on the second connector pad 70 via the third and fourth coupling capacitor pads 40 and 50.

Please refer to FIG. 6, when a second connector needs to be mounted on the second connector pad 70. (not shown), and when the high-speed differential signal control chip 10 needs to improve the signal quality, the two inductors 300 are soldered between the first and second inductor pads 80 and 90 and the selection pads 17 and 18, respectively. The second coupling capacitor 400 is soldered between the third coupling capacitor pad 40 and the common pad 12 and soldered between the fourth coupling capacitor pad 50 and the common pad 14 , and the first and second couplings are respectively Capacitor pads 20 and 30 are vacant. Thus, the high speed differential signal control chip 10 transmits the high speed differential signal through the transmission lines 102 and 104, then through the selection pads 17 and 18, through the holes 15 and 16, through the common pads 12 and 14, via the second coupling. The capacitor 400 is transmitted to the second connector on the second connector pad 70 via the transmission lines 302 and 304 via the third and fourth coupling capacitor pads 40 and 50, and the high-speed differential signal control chip 10 is transmitted through the transmission line. 102 and 104, through the selection of the pads 17 and 18, through the inductor 300, through the first and second inductor pads 80 and 90, via the transmission lines 402 and 404, the power supply is connected via the power pin Vcc, Effectively improve signal quality.

In this way, by simply providing the motherboard wiring structure, it is possible to flexibly support different connectors and improve the signal quality as needed, thereby saving the cost of the motherboard design.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

100‧‧‧Printed circuit board

10‧‧‧High speed differential signal control chip

20-50‧‧‧Coupling Capacitor

60‧‧‧First connector pad

70‧‧‧Second connector pad

80‧‧‧First Inductor Pad

90‧‧‧second inductor pad

12, 14‧‧‧ shared pads

17, 18‧‧‧Selecting the pad

102, 104, 202, 204, 302, 304, 402, 404‧‧‧ transmission lines

Vcc‧‧‧ power pin

Claims (4)

A printed circuit board having a high-speed differential signal wiring structure, comprising a high-speed differential signal control chip, first to fourth coupling capacitor pads, first and second connector pads respectively connected to different connector types, first And a second inductor pad, two first transmission lines, two second transmission lines, two third transmission lines, two fourth transmission lines, and a power supply pin for connecting a power source, the high-speed differential signal control chip, the first and fourth transmission lines The first and second inductor pads and the power supply pins are all disposed on the first layer of the printed circuit board, the second and third transmission lines, the first to fourth coupling capacitor pads, and the first and second connectors The pads are respectively disposed on the second layer of the printed circuit board, and one ends of the two second transmission lines are respectively connected to the first connector pads connected to a first type of connector, and the other ends are respectively connected to the first and second The coupling capacitor pads are connected, and one ends of the two third transmission lines are respectively connected to a second connector pad connected to a second type connector, and the other ends are respectively connected to the third and fourth coupling capacitor pads, the two fourth One end of the power line is respectively connected to the power pin, and the other end is respectively connected to the first and second inductor pads, and the second layer of the printed circuit board is between the first and third coupling capacitor pads and Two common pads are respectively disposed between the second and fourth coupling capacitor pads, one ends of the two first transmission lines are respectively connected to the output ends of the high-speed differential signal control chip, and the other ends are respectively disposed on the printed circuit board. Two select pads are connected to each other, and the two common pads are respectively connected to the two select pads through two vias, and two coupling capacitors are soldered between the first and second coupling capacitor pads and the two shared pads. The third and fourth coupling capacitor pads are shared with the two Two coupling capacitors are soldered between the pads, and two inductors or nulls can be soldered between the first and second inductor pads and the two selection pads. A printed circuit board having a high-speed differential signal wiring structure as described in claim 1, wherein the two inductors are ferrite beads. A printed circuit board having a high-speed differential signal wiring structure according to claim 1, wherein the two coupling capacitors are AC coupling capacitors. A printed circuit board having a high-speed differential signal wiring structure according to claim 1, wherein the first and second connector pads are respectively used to mount connectors of different specifications.