KR20090010801A - Printed circuit board having separate ground, and mobile terminal using thereof - Google Patents

Abstract

A PCB and mobile terminal using the same are provided to control ground length of a PCB by controlling inductance or capacitance of a connection device. A PCB comprises a substrate ground and connection devices(130, 131, 132). The substrate ground comprises main grounds(110, 111, 112) and isolation grounds(120, 121, 122). The isolation ground is separated from the main ground. The connection device is an inductor or a capacitor. A size of the main ground is larger than a size of the isolation ground. A ground length of the PCB is controlled according to inductance of the inductor or capacitance of the capacitor. If the inductance of the inductor increases, the ground length is increased. If the inductance of the inductor decreases, the ground length is decreased. If the capacitance of the capacitor increases, the ground length is decreased. If the capacitance of the capacitor decreases, the ground length is increased.

Description

Printed circuit board having separate ground, and mobile terminal using Technical Field

The present invention relates to a printed circuit board, and more particularly, to a printed circuit board that divides the substrate ground of the printed circuit board into a main ground and a separation ground, and connects the main ground and the separation ground through a connecting element.

A printed circuit board (PCB) is a circuit board in which many parts of various types are packed on a flat plate made of phenol resin or epoxy resin and the circuits connecting the parts are densely packed and fixed on the surface of the resin flat plate. to be. Printed circuit board is attached with thin plate such as copper on one side of phenol resin insulation board or epoxy resin insulation board and etched according to the wiring pattern of the circuit (corrosion and removal leaving only the circuit on the line) to construct necessary circuit and attach parts Make a hole for mounting.

In addition, flexible printed circuit boards (FPCBs), which can be flexibly handled when circuit boards such as automation devices and camcorders require movement, and when circuit boards are required to be inserted and configured, are called flexible printed circuit boards (FPCBs). do. Flexible printed circuit boards are electronic components developed as electronic products become smaller and lighter, and have excellent workability, heat resistance, and chemical resistance. Accordingly, flexible printed circuit boards are widely used in cameras, computers and peripherals, portable terminals, video and audio equipment, camcorders, printers, DVDs, TFT LCDs, satellite equipment, military equipment, and medical equipment as essential parts of all electronic products.

1 is a view showing the ground of various types of printed circuit board according to the prior art.

The printed circuit board may be formed in a structure having a plurality of layers, one of which is a ground layer serving as ground. As shown in FIG. 1, the ground of the printed circuit board may be in various forms according to the shape of the printed circuit board.

 In the case of an antenna, in particular in the case of a portable terminal, performance may depend on the ground length. The ground length of the printed circuit board is the distance between the feeding point of the antenna and the furthest distance from the feeding point. Looking at the length of each ground shown in Fig. 1, it becomes a in the case of Fig. 1A, b in the case of Fig. 1B, and c in the case of Fig. 1C. .

In order to improve the performance of the portable terminal, especially the antenna, it is important to increase the ground length. However, in the case of a printed circuit board, the length is limited, so it is very difficult to increase the ground length. In order to solve this problem, conventionally, a method of changing the physical ground length mechanically by using an electromagnetic (Electromagnetic Interference) tape or paint is used as the ground of the printed circuit board. However, this method has a problem in that the number of components of the portable terminal is required, and the manufacturing cost is added to increase the unit cost. In addition, there is a problem that a variation occurs in the characteristics of the mobile terminal due to manufacturing process error.

It is an object of the present invention to adjust the ground length of a printed circuit board by using a connection element, so that the ground length can be adjusted without changing the size of the printed circuit board.

In addition, by manufacturing a portable terminal using such a printed circuit board, it is possible to lower the manufacturing cost of the portable terminal and to reduce the process error.

In order to achieve the above objects, the printed circuit board according to the present invention includes a substrate ground and a connection element. Substrate ground includes a main ground and a separate ground. The main and separation grounds are located with gaps and are electrically connected through connecting elements. The connection element may be an inductor or a capacitor. The main ground can be larger than the isolated ground.

The printed circuit board according to the present invention can have a plurality of separation grounds. The main ground and the separated ground may be connected through adjacent ground and connecting elements, respectively.

The portable terminal according to the present invention includes a printed circuit board and an antenna. The printed circuit board has a substrate ground and a connecting element. The substrate ground has a main ground and a separation ground positioned at a gap with the main ground. The main ground and the separating ground are electrically connected via connecting elements. The antenna is connected to the board ground. The connection element may be an inductor or a capacitor.

In the portable terminal according to the present invention, the main ground may be located closer to the antenna than the separate ground. In this case, the antenna may be connected to the main ground.

According to the present invention, by separating a substrate ground of a printed circuit board into a main ground and a separation ground and electrically connecting the substrate ground, the ground length can be adjusted without changing the size of the printed circuit board. In particular, the ground length can be adjusted by adjusting the inductance or capacitance of the connecting element.

In addition, the use of such a printed circuit board in the portable terminal can reduce the manufacturing cost of the portable terminal and reduce the process error. In terms of the performance of the antenna, the ground is extended so that the performance of the antenna is improved.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings such that those skilled in the art may easily implement the present invention.

In describing the embodiments, descriptions of technical contents which are well known in the technical field to which the present invention belongs and are not directly related to the present invention will be omitted. This is to more clearly communicate without obscure the subject matter of the present invention by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. In addition, the size of each component does not fully reflect the actual size. The same or corresponding components in each drawing are given the same reference numerals.

2 is a diagram illustrating a ground of various types of printed circuit boards according to an exemplary embodiment of the present disclosure.

As shown in FIG. 2, the substrate ground of the printed circuit board includes main grounds 110, 111, and 112 and isolation grounds 120, 121, and 122. The separation grounds 120, 121, and 122 are located next to the main ground 110, 111, and 112 with a gap therebetween. The gap between the main grounds 110, 111, 112 and the separation grounds 120, 121, 122 is about 1 mm. Preferably, the size of the main grounds 110, 111, and 112 may be larger than that of the separation grounds 120, 121, and 122.

The main grounds 110, 111, and 112 and the separation grounds 120, 121, and 122 are electrically connected to each other through the connection elements 130, 131, and 132. The connection elements 130, 131, and 132 may be inductors or capacitors. Whether the connection elements 130, 131, and 132 are used as an inductor or a capacitor is determined depending on the frequency characteristics, the use of the printed circuit board, and the like. In particular, capacitors are suitable for high frequencies.

In order to adjust the length of the ground of the printed circuit board, the value of the inductance (L) of the inductor or the capacitance (C) of the capacitor is adjusted. In the case of an inductor, the larger the inductance value, the longer the ground, and the smaller the inductance value, the shorter the ground length. For capacitors, the larger the capacitance value, the shorter the ground length, and the smaller the capacitance value, the longer the ground length.

In this case, the length of the ground is not only lengthened by the connection elements 130, 131, and 132, but also by the change in the structure of the ground. When comparing (a) of FIG. 1 and (a) of FIG. 2, although the magnitude | size of all grounds is the same, the length of the ground changed from a to a1 + a2 + a3. a2 is a value determined by the connection element as described above. Obviously, a1 + a2 + a3 is larger than a.

Comparing FIG. 2 (b) and FIG. 1 (b), it can be seen that the length of the ground is the same, but the length of the ground is increased from b to b1 + b2 + b3. Even when comparing (c) of FIG. 2 and (c) of FIG. 1, it can be seen that the length of the ground has elongated from c to c1 + c2 + c3.

In this way, the substrate ground is divided into main grounds 110, 111, and 112 and separation grounds 120, 121, and 122, and in the case of connecting the main ground and the separation ground to the connection elements 130, 131, and 132, the substrate ground. The overall ground length can be made longer without changing the size of.

3 is a diagram illustrating a ground of a printed circuit board according to another exemplary embodiment of the present disclosure.

As shown in FIG. 3, the ground of the printed circuit board includes a main ground 210, a first separation ground 220, and a second separation ground 221. Each ground 210, 220, 221 is located side by side with a gap. The main ground 210 and the first separation ground 220 are electrically connected to each other through the first connection element 230. The first separation ground 220 and the second separation ground 221 are electrically connected to each other through the second connection element 231. In this case, the length of the entire ground is d1 + d2 + d3 + d4 + d5. d2 and d4 are values determined by the connection elements. Comparing this with FIG. 1B, it can be seen that the ground length is longer from b to d1 + d2 + d3 + d4 + d5.

In the present embodiment, although there are two separation grounds, three or more separation grounds may be used in consideration of the performance and structure of the printed circuit board. In this case, the connecting element should be used according to the number of separating grounds.

4 is a view showing that the ground of the printed circuit board according to the embodiment of the present invention is mounted on the portable terminal.

As shown in FIG. 4, the portable terminal 400 includes a printed circuit board and an antenna. The printed circuit board includes a substrate ground including a main ground 111 and a separation ground 121. The main ground 111 and the separation ground 121 are positioned with a gap therebetween, and are electrically connected through the connection element 131.

An external antenna may be used for the antenna of the portable terminal 400, but in recent years, an antenna, which is an internal antenna, is mainly used in consideration of the design of the portable terminal. The intenna is in a form in which the intenna pattern 411 is formed on the carrier 410. The carrier 410 on which the antenna pattern 411 is formed is mounted inside the portable terminal 400 so that the antenna is not visible from the outside. One end of the antenna pattern 411 is connected to the substrate ground of the printed circuit board.

In this embodiment, the antenna is mounted at the end of the portable terminal 400. At this time, the main ground 111 is located closer to the intenna than the separation ground 121. Thus, one end of the antenna pattern 411 is connected to the main ground 111. The reason why the separation ground 121 is located far from the antenna is because the space where the carrier 410 is mounted is insufficient to make the separation ground 121 and the connection element 131 difficult to locate.

For antennas, the required ground length depends on the frequency band and radiation performance. As in the present embodiment, when using a substrate ground in which the main ground 111 and the separation ground 121 are electrically connected using the connection element 131, the connection element 131 is appropriately adjusted so that You can create the length of the ground you want without changing its size.

A mobile terminal according to an embodiment of the present invention refers to a portable electronic device such as a mobile phone, a personal digital assistant (PDA), a portable multimedia player (PMP), a global post system (GPS) device, a navigation device, a digital broadcast receiver, and the like.

As described above, the present specification and drawings have been described with respect to preferred embodiments of the present invention, although specific terms are used, it is only used in a general sense to easily explain the technical contents of the present invention and to help the understanding of the present invention. It is not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be carried out in addition to the embodiments disclosed herein.

1 illustrates a ground of various types of printed circuit boards according to the prior art;

2 illustrates a ground of various types of printed circuit boards according to embodiments of the present invention.

3 illustrates a ground of a printed circuit board according to another embodiment of the present invention.

4 is a view showing that the ground of the printed circuit board according to the embodiment of the present invention is mounted on the portable terminal.

Claims (8)

A substrate ground having a main ground and a separation ground positioned at a gap with the main ground; And And a connection element electrically connecting the main ground and the separation ground. The method of claim 1, The connecting element is a printed circuit board, characterized in that the inductor or capacitor. The method of claim 2, And the main ground is larger than the isolation ground. The method according to claim 1 or 2, The printed circuit board, characterized in that the plurality of separation ground. The method of claim 4, wherein And the main ground and the separation ground are each connected to an adjacent ground through a connection element. A printed circuit board having a main ground and a substrate ground having a separation ground disposed to be spaced apart from the main ground, and a connection element electrically connecting the main ground and the separation ground; And And an antenna connected to the substrate ground. The method of claim 6, The connection element is a mobile terminal, characterized in that the inductor or capacitor. The method according to claim 6 or 7, The main ground is located closer to the antenna than the isolation ground, And the antenna is connected to the main ground.

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