CN1304278A

CN1304278A - Multi-layer printed circuit board

Info

Publication number: CN1304278A
Application number: CN 00101015
Authority: CN
Inventors: 杨志祥
Original assignee: Mitac International Corp
Current assignee: Mitac International Corp
Priority date: 2000-01-10
Filing date: 2000-01-10
Publication date: 2001-07-18
Anticipated expiration: 2020-01-10
Also published as: CN1173611C

Abstract

The present invention discloses a multilayer printed circuit board for reducing electromagnetic interference, and its made up by superposition of multilayer circuit layers, grounding layer, power supply layer and insulating layer, in which the insulating laeyr is respectively sandwiched between every two layers of them for producing insulating function. The surface layer of said multilayer printed circuit board is equipped with grounding layer or power supply layer for resisting electromagnetic interference. Every circuit layer possesses a circuit zone and a grounding zone, and the circuit zones of adjacent circuit layers are not mutually superposed.

Description

Multilayer board

The present invention relates to a kind of multilayer board, and be particularly related to a kind of multilayer board that reduces electromagnetic interference.

Because the consumer except powerful, more requires gently, thin, short, little to the requirement of electronic product, so electronic product integrated level on the market is more and more higher.And also begin to do more multilayer more in order to the printed circuit board (PCB) that electronic component is installed, by one deck, two layers and become six layers, eight layers, even to more than ten layers, so that make being installed on the printed circuit board (PCB) that electronic component can be more intensive, dwindle the area of printed circuit board (PCB), make the volume of electronic product littler.

Figure 1A is a kind of structural representation of traditional four layer printed circuit boards.Figure 1B is a kind of profile of traditional four layer printed circuit plate structures.

Please be simultaneously with reference to Figure 1A, 1B, multilayer board 18 is formed by insulating barrier 11 pressing in regular turn between line layer 10, ground plane 12, bus plane 14 and line layer 16 and each layer, circuit (trace) (not shown) that arranges is arranged on the line layer 10,16, electronic component 19 is installed on the line layer 10, and is connected with line electricity on the line layer 10.Bus plane 14 is connected with the power supply of supply multilayer board 18 electric power, in order to drive the circuit and the electronic component 19 that is installed on the multilayer board 18 on the multilayer board 18.And line layer 10,16 is electrically connected to each other with perforation (via) 13 between bus plane 14 and the ground plane 12.Wherein perforation 13 is made up of the coating of its periphery and the consent material of filling wherein, makes the line layer 10,16 of perforation 13 2 ends by coating, and bus plane 14 or ground plane 12 are electrically connected to each other.Ground plane 12 and bus plane 14 are configured between the line layer 10,16, are in order to separate line layer 10,16, to avoid the circuit on the line layer 10,16 too closely to produce crosstalk phenomenon (cross talk) because of distance.

Electronic component can generate electromagnetic waves and disturb near the operation of other electronic components in work, is called the electromagnetic interference phenomenon.Along with the integrated level of electronic component is more and more higher, function is become stronger day by day, so the service speed of electronic component is also and then more and more faster, and frequency of operation also frequently comes highly more, makes and causes the electromagnetic interference phenomenon between electronic component more serious by electromagnetic intensity grow.On the other hand, the circuit on the multilayer board line layer time also has electromagnetic wave in work and produces, and line layer is positioned at the outermost layer of whole multilayer board structure, makes electromagnetic wave radiate easily.And improve when the frequency of operation of electronic component, the line loop operation frequency on the multilayer board also must and then improve, so multilayer board also has the problem that the electromagnetic interference phenomenon strengthens and produces.

Since the electromagnetic interference phenomenon can to around electrical equipment exert an influence, severe patient even can cause harm on the safety, therefore the effect that gets involved for the electromagnetism that electrical appliance produced of nearly all country all has quite strict regulation surely.So reducing the electromagnetic interference phenomenon all is a very important problem for most of electrical appliance producer.

The purpose of this invention is to provide a kind of multilayer board that reduces electromagnetic interference, can reduce the electromagnetic interference phenomenon that multilayer board produces.

For achieving the above object, the invention provides a kind of multilayer board that reduces electromagnetic interference, be formed by stacking by multilayer line layer, ground plane, bus plane and insulating barrier.And between line layer, ground plane and bus plane all at interval wherein with insulating barrier, with usefulness as insulation.The top layer system configuration ground plane or the bus plane of multilayer board are to prevent electromagnetic interference.Line layer all has a circuit zone and a ground area, and the circuit zone of adjacent lines layer is not overlapped each other.

The present invention is disposed at ground plane in the multilayer board or bus plane the outermost layer of multilayer board structure, and line layer is coated on the internal layer of multilayer board structure, can avoid because of the circuit on the line layer in when work, give off electromagnetic wave and produce the electromagnetic interference phenomenon.

For above-mentioned and other purposes, feature and advantage of the present invention can be become apparent, preferred embodiment cited below particularly, and conjunction with figs. is described in detail below, wherein

Figure 1A is a kind of structural representation of traditional four layer printed circuit boards;

Figure 1B is a kind of profile of traditional four layer printed circuit plate structures;

Fig. 2 A is the structural representation of four layer printed circuit boards according to one preferred embodiment of the present invention;

Fig. 2 B is the profile of four layer printed circuit plate structures according to one preferred embodiment of the present invention; And

Fig. 3 is the structural representation of the printed circuit board (PCB) of another preferred embodiment according to the present invention.

Fig. 2 A is the structural representation of four layer printed circuit boards according to one preferred embodiment of the present invention, and Fig. 2 B is the profile of four layer printed circuit plate structures according to one preferred embodiment of the present invention.

Please be simultaneously with reference to Fig. 2 A, 2B, multilayer board 28 is formed by insulating barrier 34 pressings between ground plane 20, line layer 22, line layer 24, bus plane 26 and each layer.Be formed with the circuit (not shown) that arranges on the line layer 22,24.Bus plane 26 is connected in the power supply to multilayer board 28 supply electric power, drives circuit and the electronic component 29 that is installed on the multilayer board 28 on the multilayer board 28.The material of insulating barrier 34 comprises glass epoxide base resin (FR-4, FR-5), or the bismaleimide triazine (Bismaleimide-Triazine, BT) etc.And line layer 22,24 is electrically connected to each other with perforation 36 between bus plane 26 and the ground plane 20.Wherein perforation 36 comprises the coating of its periphery and the consent material of filling is wherein formed, by coating make the line layer 22,24 of perforation 36 2 ends and power supply lead 26 or ground plane 20 be electrically connected to each other.Electronic component 29 is installed on the ground plane 20, is connected by the line electricity of the perforation 36 that forms in the insulating barrier 34 with line layer 22,24.

In addition, on the line design of line layer 22,24, define ground area 30,32 and circuit zone 38,40 respectively, wherein the position non-overlapping of circuit zone 38,40 on line layer 22,24.With the present embodiment is example, and circuit zone 38 is formed on the RHP of line layer 22, and circuit zone 40 then is formed on the left half-plane of line layer 24, shown in Fig. 2 A.Because the circuit of line layer 22 zone 38 is not overlapping with the circuit zone 40 of line layer 24, therefore more can prevent crosstalking between circuit.

In the present embodiment, line layer 22,24 is the internal layer that is disposed at multilayer board 28 structures, skin then coats line layer 22,24 with ground plane 20 and bus plane 26, such collocation form can utilize ground plane 20 and bus plane 26 that the circuit on the line layer 22,24 is covered, avoid the circuit on the line layer 22,24 when work, to give off electromagnetic wave, in the time of can improving because of the multilayer board line work, give off electromagnetic wave and the electromagnetic interference phenomenon that causes.

The present invention is disposed at ground plane and bus plane on the surface of multilayer board structure, the electromagnetic wave that goes out with the line radiation of avoiding on the line layer produces the electromagnetic interference phenomenon, though the multilayer board that present embodiment is lifted is a four-layer structure, yet the present invention is not limited to the multilayer board of four-layer structure, other multilayer board equally also can be used the present invention and improve the electromagnetic interference phenomenon as six layers, eight layers or the more number of plies.Also be not limited to rule configuration as for the configuration in ground area in the line layer and circuit zone by above-mentioned left and right one side of something.

Use the present invention when the multilayer board of the more number of plies, design according to printed circuit board (PCB) of the present invention, respectively ground plane or bus plane are disposed at the outermost layer of multilayer board structure, line layer is disposed at the internal layer of multilayer board structure, and the non-overlapping each other of the circuit regional location on adjacent each line layer.But in the multilayer board of the high number of plies, have the not only ground plane or the bus plane of one deck, so also can dispose ground plane or bus plane at outermost layer, and line layer is disposed at the internal layer of multilayer board structure, remaining ground plane or bus plane are interspersed between line layer, so can reduce crosstalking between the electromagnetic interference phenomenon of multilayer board and line layer equally.

Please refer to Fig. 3, be depicted as structural representation according to the printed circuit board (PCB) of another preferred embodiment of the present invention.Be example with six-layer printed circuit board 70 again, it has two ground planes, 50,60, one bus planes 56, and three

line layers

52,54,58.According to design principle of the present invention, the skin of printed circuit board (PCB) 70 disposes

ground plane

50,60 respectively.And

adjacent lines layer

52,54 has

circuit zone

52a, 54a respectively, and

ground area

52b, 54b, and is wherein not overlapped each other between circuit zone 52a, 54a.As for 58 of line layer 54 and line layers, owing to there is bus plane 56 to intercept, can effectively completely cut off crosstalk phenomenon, so the line configuring of 54,58 of line layers is then unrestricted.

By the invention described above preferred embodiment as can be known, use the present invention and have following advantage.The outermost layer that the ground plane or the bus plane of multilayer board is disposed at the multilayer board structure, and line layer is coated on the internal layer of multilayer board structure, can avoid producing the electromagnetic interference phenomenon because of the circuit on the line layer gives off electromagnetic wave when the work.And utilize the not overlapped design in circuit zone between line layer, more can prevent the crosstalk phenomenon between line layer.

Though the present invention is illustrated in conjunction with the preferred embodiments, so it is not in order to qualification the present invention, for the industry, and without departing from the spirit and scope of the present invention, can do various changes and retouching.

Claims

1. multilayer board comprises:

One ground plane;

One bus plane;

One first line layer;

One second line layer;

Multilayer dielectric layer;

Described multilayer board is superimposed and form by described ground plane, bus plane, first line layer, second line layer and described insulating barrier, and one of described insulating barrier of configuration between adjacent ground plane, bus plane, first line layer, second line layer, usefulness with as insulation is characterized in that

Have a ground area and a circuit zone on described first line layer; Described second line layer has a ground area and circuit zone; And described ground plane and bus plane are disposed at the upper and lower surface of described multilayer board respectively, and the circuit zone of the circuit of described first line layer zone and described second line layer does not overlap each other.

2. multilayer board as claimed in claim 1 is characterized in that, the material of described insulating barrier is a kind of among BT, FR-4 and the FR-5.

3. multilayer board comprises:

One ground plane;

One bus plane;

It is characterized in that described multilayer board also comprises,

The multilayer line layer wherein has a ground area and a circuit zone on each line layer; And

Multilayer dielectric layer, this multilayer board is superimposed and form by described ground plane, bus plane, line layer and insulating barrier, and one of described insulating barrier of configuration between adjacent ground plane, bus plane, line layer, with usefulness as insulation, and described ground plane and bus plane are disposed at the upper and lower surface of this multilayer board respectively, and the circuit zone of adjacent lines layer does not overlap each other each other.

4. multilayer board as claimed in claim 3 is characterized in that, the material of described insulating barrier is a kind of among BT, FR-4 and the FR-5.

5. a multilayer board is characterized in that, described multilayer board comprises:

The multilayer ground plane;

The multilayer bus plane;

The multilayer line layer wherein all has a ground area and a circuit zone on each line layer; And

Multilayer dielectric layer, wherein this multilayer board is superimposed and form by described ground plane, bus plane, line layer and insulating barrier, and one of described insulating barrier of configuration between adjacent ground plane, bus plane, line layer, with usefulness as insulation, and the upper and lower surface of this multilayer board disposes one of described ground plane and described bus plane respectively, and the circuit zone of adjacent lines layer does not overlap each other each other.

6. multilayer board as claimed in claim 5 is characterized in that, the material of described insulating barrier is a kind of among BT, FR-4 and the FR-5.