JPH06152079A - Printed wiring board - Google Patents

Abstract

PURPOSE:To improve electromagnetic noise radiation characteristics and stable operation property under electromagnetic noise environment easily and inexpensively by coating a magnetic body near the surrounding of a hole for mounting the lead of electronic parts formed at a printed circuit board. CONSTITUTION:In a printed wiring board 10 where a circuit pattern is drawn, a substrate 11 is a glass epoxy one-sided substrate and the printed wiring board 10 is used for mounting electronic parts 12 such as ICs, resistors, and capacitors. Then, a magnetic body 15 such as ferrite and amorphous alloy is coated near the surface of the surrounding of a hole 14 where a lead 13 for mounting the electronic parts 12 is mounted. thus improving the electromagnetic noise radiation characteristics and stable operation property under electromagnetic noise environment easily and inexpensively without inserting a special inductance element in series. In the printed wiring board. a glass epoxy double-sided substrate, a glass epoxy multilayer substrate, and a substrate where a magnetic body such as ferrite is spread as an intermediate layer are used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board used for mounting electronic parts, and is particularly devised to improve electromagnetic noise emission characteristics and stable operability in an electromagnetic noise environment.

[0002]

2. Description of the Related Art In recent years, radiation of electromagnetic noise from electronic parts has become a problem. Most of this noise can be removed by a filter composed of an inductance and a capacitance. Conventionally, as shown in FIG. 2, for example, an inductance element, a capacitor, or a combination of them is connected in series with an electronic component 21. Filter 2
2 was mounted on the substrate as an individual component.

[0003]

However, there is a problem that there is no space to mount the filter 22 such as the above-mentioned inductance element due to high density mounting of components, and further, there is a problem that it cannot be manufactured at low cost. is there.

In view of the above problems, it is an object of the present invention to provide a printed wiring board which is easily and inexpensively improved in electromagnetic noise emission characteristics and stable operability in an electromagnetic noise environment.

[0005]

The structure of a printed wiring board according to the present invention for achieving the above object is a printed wiring board used for mounting an electronic component, and a lead of the electronic component formed on the printed circuit board is provided. It is characterized in that a magnetic material is applied near the periphery of the mounting hole.

[0006]

[Function] By applying a magnetic material such as ferrite around the holes for mounting leads of ICs, resistors, capacitors, and other electronic parts of the printed wiring board, it is equivalent to inserting an inductance in series with these elements. The effect can be obtained, and the electromagnetic noise emission characteristics and the stable operability in the electromagnetic noise environment can be improved.

[0007]

The preferred embodiments of the present invention will be described in detail below.

FIG. 1 is a perspective view of a printed wiring board according to this embodiment. As shown in the figure, in the printed wiring board 10 on which a circuit pattern is drawn, the substrate 11 is a glass epoxy single-sided substrate and is used for mounting ICs, resistors, capacitors, and other electronic components 12.

In this embodiment, a magnetic material 15 such as ferrite or amorphous alloy is applied to the vicinity of the surface around the hole 14 for mounting the lead 13 for mounting the electronic component 12. As a result, unlike the conventional case, the electromagnetic noise emission characteristics can be easily and inexpensively inserted without inserting a special inductance element in series. It was possible to improve the stable operation under the electromagnetic noise environment.

In addition to the structure shown in FIG. 1, the printed wiring board used for mounting the above-mentioned electronic parts has a glass epoxy double-sided board, a glass epoxy multi-layered board, and a ferrite intermediate layer. Of the magnetic material, the substrate is a single-sided ceramic substrate, the substrate is a double-sided ceramic substrate, the substrate is a multilayer ceramic substrate, and the intermediate layer is coated with a magnetic material such as ferrite. be able to.

[0011]

As described above with reference to the embodiments, the printed wiring board according to the present invention has the IC, resistance,
Since magnetic material is applied around the holes where the leads of capacitors and other electronic parts are mounted, it is easy and cheap to insert high-density mountability without inserting a special inductance element as in the past. Therefore, the electromagnetic noise radiation characteristic can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a printed wiring board.

FIG. 2 is a schematic diagram of an equivalent circuit.

[Explanation of symbols]

 10 Printed Wiring Board 11 Board 12 Electronic Component 13 Lead 14 Hole 15 Magnetic Material

Claims (1)

[Claims] 1. A printed wiring board used for mounting an electronic component, characterized in that a magnetic material is applied in the vicinity of a hole for mounting a lead of the electronic component formed on the printed circuit board. Board.