JPS5878497A - Multilayer printed circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electronic component mounting and q#i! The present invention relates to a multilayer printed wiring board composed of at least two or more conductor layers used for wires and the like.

Yuna (also known as multilayer pudding made of two or more conductor layers)
An example of the wiring board is shown in (1, (1).

An an layer 2 extending in a band shape on one side of the insulator 1! 1 is installed, and both power supply layers or ground layers 3 on the other side of the insulator 1 are formed. To change the impedance on a printed wiring board such as **, you have to change the width and spacing of the signal wiring or the thickness of the insulator 1, which is an inconvenient decision.I! Now, assuming that a multilayer printed wiring board is used, and its characteristic Ishibi dance is changed without changing the thickness, material, signal line width, etc. between 70 layers, the 1m2 figure is (1. It is known that in QIJ, a circular conductor part is cut out to correspond to the signal wiring in the ground layer or power supply layer 3 that is in contact with the signal layer 2 like a layered layer. This area is called clearance 4, but in conventional printed wiring boards, it is the circular clearance mentioned above.
As shown in IIK, signal wiring 2 (υ, 3(2), -2-
Due to the positional relationship between the clearance 4 and the clearance 4, the uniformity of each overlap is slightly different Ik-p, so there is a large difference in the characteristic of the signal wiring '-/)/X, and in addition, Even if the position of the signal wiring line ψ array 4 is shifted, the tatami line resistance of the single wiring line changes.

Also.

As shown in 114■, each signal wiring 2 (1), 2 (2) - is made by combining multiple circular clearances 4 at 5.
Even if an attempt is made to reduce the variation in the characteristic impedance of 2(2), it is not possible to change the 4I impedance due to the positional deviation between the signal wiring and the clearance 4.

It is an object of the present invention to solve the above-mentioned drawbacks by making the clearance of the ground layer or one power layer polygonal, to reduce the characteristic impedance of all signal wiring, and to reduce the increase in the characteristic impedance of all signal wiring. It is our goal to provide a multilayer printed wiring board that eliminates changes in characteristic impedance due to misalignment.

The present invention provides a multilayer printed wiring board that is composed of at least one conductor layer and in which a signal layer and a ground layer or a -1 signal layer and a conductor layer are adjacent to each other. Polygonal clearances are regularly provided at positions within the ground layer or source layer that face the signal wiring within the layer.

Next, please refer to @wt, ml- for details on the examples! -do.

5 to 10 schematically show each embodiment of the present invention, and the % symbol S represents a lattice provided on a board, and the lattice shown in FIG. The board is
2 is a signal wiring in the signal layer, which is divided into square parts having the same area.

The shaded area 4 in the figure is the ground layer and 111LIII
It shows a rectangular or square clearance provided in J1, provided throughout the grid.

Chapter Sa! ll is an embodiment of turtle 1 of the present invention. By making the clearance rectangular and making the overlapping area of the signal wiring 5 and clearance 4 constant, each signal wiring 2 (support)
, 2@, -1(2), and eliminates changes in the characteristic impedance due to positional deviation of the signal wiring array 4. The mail is an example of lI2, and a rectangular clearance 4 is provided on the toothpick as shown in the figure, and the effect is that of the pigeon house sail of the first example, and the code size of 1s6■.
Even in a place where the preparation 4 # wiring intention - which is formed within the Is child runs -, the 4) redemption of 20 parables is small. The 711th is an example of wi3, and is a Crypran.

By making it square, it is possible to reduce fluctuations in the characteristic impedance of the signal wiring 2 in both the vertical and horizontal directions, and also to reduce the 4I impedance against misalignment between the wiring 2 and the clearance 4. Figure 8 shows the 10th embodiment, which is made into a rectangular shape and provided on all four sides of the grid, and this effect has a characteristic impedance for each signal wiring 2 in the vertical and horizontal directions.

and against misalignment between the signal layer and clearance 4*
*In addition to the change in impedance, the variation in characteristic impedance can be reduced even if the signal wiring is bent within the lattice.

FIG. 9 shows an S-th embodiment, in which a rectangular clearance 4 is provided diagonally. The effect is the same as the rattan 7116 rattan 3 example pigeon coop, and in addition [more conductive layer parts can be taken! Therefore, it is possible to reduce the power supply voltage f1 and the power supply voltage difference.

In the j11G111th implementation, j1 rectangular clearance 4 is provided at the intersection of the signal wiring 2 and the grid,
In addition to the effects of the embodiment 17h4 in Fig. 8, a large portion of the conductor layer can be used to reduce ground drop and electric current.
It is possible to reduce the pressure dope in Al1 by a force of 1.

As explained above, the present invention reduces variations in the characteristic impedance of the J signal wiring by making the clearance polygonal, and prevents changes in characteristic impedance due to positional deviation between the force/signal wiring and the clearance. effective.

[Brief explanation of the drawing]

1a1 (older sister, (to)) is a perspective view of a conventional printed circuit board composed of at least two or more conductor layers, mzli
(~, (2) is the diagonal man% rattan 3- of the conventional printed circuit board of the pigeon house with clearance and the 411th conventional printed circuit board with circular clearance) Perspective from the signal layer of the board-, $15 garden- The 10114th edition of this book (multilayer print) shows examples of each of the wiring boards. l-candy body, 2-(Signal wiring of layer 1. S-TG layer (ground layer), 4... Clearance, 5- Lattice. Agent Patent attorney Rikichi Higashikawa Figure 1 (a) Figure 1 (b) Figure 2 (a) Figure 2 (b) Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 2 ShiyJ Figure 9

Claims (1)

[Claims] In a multilayer printed wiring board that is composed of at least two or more conductor layers and in which a signal layer and a ground layer or a signal layer and a power supply layer are adjacent to each other, the ground layer faces the signal wiring in the above-mentioned layer. 1. A multilayer printed wiring board characterized in that a clearance portion in which a conductor is hollowed out in a polygonal shape is provided at a position inside or within a power supply layer.