JP3678113B2 - Printed circuit manufacturing method and portable communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printed circuit manufacturing method and a portable communication device, and more particularly to a printed circuit manufacturing method and a portable communication device with improved shielding effect against radiation noise and the like.
[0002]
[Prior art]
Conventionally, countermeasures against malfunctions caused by radiation interference noise generated from mobile communication devices such as mobile phones and external noise to mobile communication devices have been made by enclosing the case of the mobile communication device with a conductive substance and performing electrostatic shielding. Is made by. In particular, in the printed wiring circuit that is the source of radiation noise, use noise countermeasure parts such as EMI (Electro-Magnetic-Interference) filters in the printed wiring circuit, and wrap the printed wiring circuit with a metal cover. Shielding is strengthened by taking a double measure.
[0003]
FIG. 2 is a perspective view of a conventional printed wiring circuit in which electrostatic noise shielding is enhanced. In the example shown in FIG. 2, the shielding is strengthened by wrapping the entire electronic component mounted on the printed wiring board 50 and the formed printed wiring circuit (both not shown) with a metal cover 52. ing. Here, the metal cover 52 is electrically connected to the ground potential whole surface layer of the lowermost outer layer of the printed wiring board 50, thereby performing noise shielding. Further, in order to prevent noise from leaking into the space from the printed wiring board 50, the connection portion 54 between the printed wiring board 50 and the metal cover 52 is fixed by a soldering or mechanical crimping method. Yes.
[0004]
[Problems to be solved by the invention]
By the way, in the connection portion 54 between the printed wiring board 50 and the metal cover 52, soldering work or the like is performed over the entire periphery of the connection portion 54 between the ground pattern formed on the printed wiring board 50 and the metallic cover 52. However, there is a problem that it takes time to assemble and there is a difficulty in assembling manufacturability. In addition, when there is a space between the metal cover 52 and the printed wiring board 50, the component mounting density is not suitable for reducing the size and weight of the communication device.
[0005]
The present invention has been made in view of the above circumstances, and can effectively shield radiated noise and external noise, and can be easily manufactured and reduced in size and weight. An object of the present invention is to provide a circuit manufacturing method and a portable communication device.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, a printed circuit manufacturing method of the present invention is provided with an electronic component , and conductive terminal layers and insulating layers are alternately stacked, and a connection terminal is provided on a component surface on which the electronic component is disposed. A flexible printed wiring board provided with a printed wiring board and an electronic component , in which conductive pattern layers and insulating layers are alternately stacked, and connection terminals are formed on the four peripheral portions of the electronic component. using the circuit, the said connection terminals formed on each Rutotomoni the printed wiring board to form electronic components are opposed and the printed wiring electronic component formed on the circuit around 4 surface portion of the electronic component are opposed, and the electronic component such that each is disposed inside bending the printed wiring circuit, contact the anisotropic conductive the connection terminal facing around 4 surface portion of the electronic component By connecting secured using wood, it is characterized by electrically connecting the ground of the ground and the printed circuit of the printed wiring board.
In the printed circuit manufacturing method of the present invention, the outermost layer serving as the ground of the printed wiring board and the outermost layer serving as the ground of the printed wiring circuit are all solid layers, and the adhesive is formed through a through hole. Are electrically connected to each other.
According to another aspect of the present invention, there is provided a portable communication device including a printed circuit manufactured by using the printed circuit manufacturing method described above.
[0007]
More specifically, the present invention relates to a printed circuit manufacturing method comprising a printed wiring board constituting the bottom surface and a flexible printed wiring circuit that wraps the upper surface portion of the printed wiring circuit, and the printed wiring board constituting the bottom surface is an electronic component. And a pattern layer on which conductive patterns are formed, and a ground layer on the entire outermost layer. In addition, the flexible printed circuit that wraps the upper surface also has a conductive pattern layer on which electronic components are mounted, an insulating layer alternately laminated under the pattern layer, and a pattern layer on which the conductive pattern is formed, and the entire surface is grounded on one outer layer. A wiring circuit that folds an electronic component inward to connect the potential of the entire ground layer of the printed wiring circuit and the entire ground layer of the lowermost outer layer of the printed wiring board in the four surrounding areas. Method of joining the printed wiring board and the printed wiring circuit and the wiring circuit in forming an integrated structure in which the potential of the printed wiring board is connected to the whole surface ground layer in four directions around the ground layer of the printed wiring circuit It is characterized by connecting and fixing using an anisotropic conductive adhesive.
The conductive layer of the ground potential that is located on the outermost periphery and is electrically coupled in a form that encloses the printed wiring circuit and the electronic component shields noise emitted from the printed wiring circuit and electronic component and external noise. Perform the action. Therefore, the malfunction of the circuit of the mobile communication device can be reduced, and the malfunction of the external electronic device can be reduced.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a printed circuit manufacturing method and a portable communication device according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a method of manufacturing a printed circuit according to an embodiment of the present invention. As shown in FIG. 1, the printed circuit manufacturing method according to the present embodiment is configured by integrally forming a planar printed wiring board 10 and a flexible printed wiring circuit 20 constituting the bottom surface.
[0009]
The printed wiring board 10 is formed by alternately laminating a conductive pattern layer (for example, a copper foil layer) on which a wiring circuit for transmitting a power supply voltage and a signal is formed, and an insulating layer, and the outermost layers on both sides are conductive layers. It is formed and the surface is, for example, a known resist film. In addition, the electronic components 12 to 18 are electrically connected to the conductive pattern of the outermost layer, and the end of the wiring circuit on the component surface where these electronic components 12 to 18 are arranged is connected to the printed wiring circuit 20. Terminals for signal connection are provided. Further, the conductive pattern of the lowermost outer layer is connected to the ground potential of the component surface by a self-wiring via a via hole (or a through hole), and the entire surface layer is at the ground potential.
[0010]
The flexible printed wiring circuit 20 is a known one in which a conductive pattern layer (for example, a copper foil layer) on which a wiring circuit for transmitting a power supply voltage and a signal is formed and an insulating layer are alternately stacked. The shape is set such that the connected electronic components 22 to 28 are folded back and wrapped on the side where the electronic components 22 to 28 are provided. In addition, a terminal for signal connection with the printed wiring board 10 is provided in the connection fixing portion 30 at the end of the wiring circuit. Further, the outermost conductive layer is a solid layer on the entire surface, and is at a ground potential by electrical connection via a connection terminal with the ground entire surface layer of the printed wiring circuit 20.
[0011]
In the connection fixing part 30, the printed wiring board 10 and the printed wiring circuit 20 are structurally connected and fixed to each other by using an anisotropic conductive adhesive. Here, the anisotropically conductive adhesive is a known adhesive having a property of conducting electricity only in a direction perpendicular to the surface of the printed wiring board 10, that is, in a vertical direction in the drawing. Therefore, contact conduction is possible between the signal terminals of the printed wiring circuit 20 facing the signal terminals of the printed wiring board 10, but electrical connection is made between other signal terminals arranged on the plane of the printed wiring board 10. Insulated.
[0012]
The connection fixing part 30 is provided in the four directions around the printed wiring circuit 20 and is configured to wrap around the printed wiring circuit and electronic components in the shape of a quadrangular prism. In addition, in the quadrangular prism-shaped quadrangular portion formed by the printed wiring circuit 20, a gap (slit) is slightly generated without being overlapped with the ground potential layer, but the width of the slit is blocked by the width. If it is less than 1/4 to 1 / 3.3 of the required noise wavelength, it is sufficient as practical shielding performance and does not cause a problem. This gap may be further fixed with a conductive tape.
In the printed circuit manufacturing method according to the embodiment of the present invention described above, the ground potential electrically coupled to the outermost peripheral layer of the printed wiring board 10 and the flexible printed wiring circuit 20 so as to enclose the printed wiring circuit and the electronic component. The conductive layer is provided. Therefore, the conductive layer of the ground potential, which is located on the outermost periphery and is electrically coupled in the form of enclosing the printed wiring circuit and the electronic component, shields the noise emitted from the printed wiring circuit and the electronic component and the external noise. It becomes.
[0014]
Therefore, by incorporating a printed wiring circuit with such a shielding measure into a portable communication device, it is possible to reduce malfunction of the circuit of the portable communication device and to reduce malfunction of an external electronic device. Moreover, since a metal cover is not required as in the prior art, the device can be reduced in size and weight. Furthermore, in this embodiment, the structure of the printed wiring board 10 and the printed wiring circuit 20 and the connection at the connection fixing portion 30 of the wiring circuit terminals are connected and fixed using an anisotropic conductive adhesive. The manufacturability of the device can also be improved.
[0015]
【The invention's effect】
As described above, according to the present invention, a conductive layer having a ground potential that is electrically coupled to the outermost peripheral layer of the printed wiring board and the flexible printed wiring circuit so as to wrap the printed wiring circuit and the electronic component is provided. Therefore, the conductive layer of the ground potential that is located on the outermost periphery and is electrically coupled in a form that encloses the printed wiring circuit and the electronic component is resistant to noise emitted from the printed wiring circuit and the electronic component and external noise. It becomes shielding. Therefore, the malfunction of the circuit of the mobile communication device can be reduced, and the malfunction of the external electronic device can be reduced. In addition, there is an effect that the device can be reduced in size and weight. In addition, since the connection fixing portion between the printed wiring board and the printed wiring circuit is connected and fixed using an anisotropic conductive adhesive, there is an effect that the manufacturability of the device can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a method for manufacturing a printed circuit according to an embodiment of the present invention.
FIG. 2 is a perspective view of a conventional printed wiring circuit in which electrostatic noise shielding is enhanced.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Printed wiring board 12-18 Electronic component 20 Printed wiring circuit 22-28 Electronic component 30 Connection fixing part

Claims (3)

A printed wiring board provided with electronic components , in which conductive pattern layers and insulating layers are alternately stacked and connection terminals are formed on a component surface on which the electronic components are arranged ,
An electronic component is provided, and a conductive printed layer and an insulating layer are alternately stacked, and a flexible printed wiring circuit in which connection terminals are formed in the four peripheral portions of the electronic component ,
The connection terminals formed on each Rutotomoni are opposed to the electronic components formed on said printed circuit board to form electronic components the printed circuit are opposed around 4 surface portion of the electronic component, and wherein Bending the printed wiring circuit so that each electronic component is placed inside,
By electrically connecting and fixing the connection terminals facing each other in the four peripheral areas of the electronic component using an anisotropic conductive adhesive , the ground of the printed wiring board and the ground of the printed wiring circuit are electrically connected. A method of manufacturing a printed circuit, characterized by connecting. The outermost layer serving as the ground of the printed wiring board and the outermost layer serving as the ground of the printed wiring circuit are all solid layers, and each is electrically connected by the adhesive through a through hole. A method of manufacturing a printed circuit according to claim 1. A portable communication device comprising a printed circuit manufactured using the printed circuit manufacturing method according to claim 1.

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