JPS63174392A - Printed wiring 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 [Field of Industrial Application] The present invention relates to a printed wiring board on which an LSI or the like is mounted, and particularly to a printed wiring board suitable for improving electrostatic noise resistance.

[Conventional technology]

Conventionally, printed wiring boards with high noise resistance have a multilayer board, in which a copper plate called an inner layer is arranged in addition to the surface of an insulating base material, and the surfaces on both sides of the insulating base material are mainly used as circuit forming layers. The inner layer has a sandwich structure with a power supply layer and a ground layer, and a capacitor is formed between the inner layer copper plates to have the effect of a bypass capacitor, improving noise resistance.

On the other hand, Electronic Packaging Chikunoroshii published by Information Research Committee Co., Ltd.
c Packaging Technology)
A single-sided multilayer substrate, which is discussed in '86/1, pages 45-49, has been proposed.

[Problem that the invention seeks to solve]

In the conventional technology described above, although the multilayer board has high noise resistance, it is very expensive because it uses a glass base material and a copper plate for the inner layer. In addition, in the case of a single-sided multilayer board, the printed wiring board itself is inexpensive because the copper plate is on one side, but its noise resistance is poor, so a shield plate made of metal is installed on the side opposite to the circuit formation layer. There is a need. Installing this shield plate imposes restrictions on the structure of the electronic device, and furthermore, it takes time and effort to install it, resulting in an expensive product and requires consideration of the insulation of the shield plate.

An object of the present invention is to provide a printed wiring board that is inexpensive and has high noise resistance.

[Means for solving problems]

The present invention uses a double-sided printed board that has metal conductor layers on both sides of an insulating base material, one side is a circuit formation layer, the other side is a ground layer, and the circuit formation layer is placed on this ground layer via an insulating layer. It is characterized by having been established.

[Effect]

Since one metal conductor layer of the double-sided printed board is interposed as a ground layer between the two circuit forming layers, this ground layer is coupled to the circuit forming layer at a low impedance and a shielding effect is obtained.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 1 and 2.

The conductor layer on one side of the insulating base material 1 is used as a circuit formation layer, and a land 38 circuit pattern 3b and a ground connection pattern 3c are formed for mounting components, and the conductor layer on the opposite side is used as a ground layer and a ground pattern 2 is formed by etching. In addition, holes for inserting parts 9, holes for passing connection wires 5, etc. are formed by machining.

An insulating layer 7 is printed on the ground pattern 2, a conductive paste (copper paste here, not shown) is printed on top of the insulating layer 7, and a copper plating layer is formed by electroless plating. A circuit pattern 4 is formed on 7. After that, solder resist 8 is printed on both sides. The earth connection pattern 3c is further connected to the earth pattern 2 on the opposite side via a connection wire 5, the circuit pattern and the soldering layer 6. However, earth connection pattern 3
c does not necessarily need to be connected to the ground pattern 2, and may be connected to the circuit pattern 4 in some cases. That is, it serves as a mutual grounding point for metal conductors located on both sides of the insulating base material 1 or as a signal connection.

Although the connection wire 5 has been explained as being attached during the manufacturing process of the printed wiring board, since the electronic components etc. are mounted on the printed wiring board and then soldered to make the desired electrical connection, the process of mounting the electronic parts is not necessary. If the connecting wire 5 is also mounted on the tower at the same time, the process can be omitted and an efficient construction method is possible.

〔Effect of the invention〕

According to the present invention, since a double-sided printed circuit board is used and the metal conductor layer on one side is arranged as a ground layer between two circuit formation layers, it is possible to obtain a printed wiring board that is inexpensive and has high noise resistance. Can be done.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of a printed wiring board showing an embodiment of the present invention, and FIG. 2 is a manufacturing process flowchart. 1... Insulating base material, 2... Earth pattern, 3b...
-Circuit pattern, 4...Circuit pattern, 7...Insulating layer.

Claims (1)

[Claims] 1. Using a laminate having metal conductor layers on both sides of an insulating base material, one side is a circuit forming layer and the other side is a grounding layer, an insulating layer is formed on this grounding layer, and a circuit is formed on this insulating layer. A printed wiring board characterized by having layers.