JP2007174540A - Small radio apparatus, printed circuit board of small radio apparatus and, method of mounting component of small radio apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small radio apparatus capable of improving antenna characteristics, preventing electrostatic discharge damage, and improving mounting efficiency of components, a printed circuit board of the small radio apparatus, and a method of mounting the components of the small radio apparatus. <P>SOLUTION: A copper foil pattern 102 of the printed circuit board 100 in which components such as an external interface connector 6 or the like covered with a metal plate are mounted at a lower part of the antenna 1 or the like, and a copper foil pattern 101 of the printed circuit board 100 constituted as a reference ground of electric circuit components 2-5 and the antenna 1 of the device body are electrically divided, and mutually connected by an inductance element 7 being open in a desired radio band. The inductance element 7 suppresses the occurrence of capacitive impedance between the components and the antenna in radio frequencies so as to prevent the antenna characteristics from being deteriorated. Further, the common reference potential upon operation can be secured by the inductance element 7. Furthermore, static electricity impressed on the components is released through the inductance element 7, preventing the electrostatic discharge damage of electric components. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a small wireless device such as a mobile phone and a wireless communication device, and more particularly to a small wireless device capable of mounting components around an antenna, a printed circuit board of the small wireless device, and a component mounting method.

  Small wireless devices typified by mobile phones have achieved miniaturization by efficiently mounting a large number of components in the main unit, but mounting an antenna is indispensable for wireless communication, and there is an electric circuit in the vicinity. Arranging components or the like may deteriorate antenna characteristics and cause deterioration of radio characteristics.

  For this reason, in conventional small wireless devices, electrical circuit components other than the antenna portion are collectively accommodated in a shield case, or the outer surface of an electronic component in the vicinity of the antenna portion is formed by a conductor portion such as a metal case, and the outer surface thereof is formed. The connected case terminal is directly connected to the ground portion of the printed circuit board by solder or the like to perform shielding (see Patent Document 1, FIG. 3, 1, paragraphs 0002 and 0008).

In addition, the ground portion is electrically connected via a coil component between one circuit board having an antenna of a foldable mobile phone and the other circuit board, so that a phase difference is provided to a circuit board without an antenna. It is also known to actively generate a given high-frequency current to reduce an adverse effect on antenna gain (see Patent Document 2, paragraph 0027).
Japanese Patent Laid-Open No. 11-220420 JP 2003-273767 A

  In small wireless devices such as mobile phones, PHS (Personal Handyphone System), PDA (Personal Data Assistance, Personal Digital Assistants), a number of components are included in the main body to achieve downsizing. It is important to implement efficiently using any space.

  In addition, when mounting an electric circuit component or the like made of at least a part of metal, in addition to the shield as described above, an electric circuit including the electric circuit component is formed on a common reference potential. It is indispensable to connect this metal part to the reference ground with solder etc., and to fix it mechanically, due to the necessity of electrical circuit components, the strength of electrical circuit components, and the necessity of electrostatic discharge. There are often.

  However, when such an electric circuit component is placed near the antenna or the like, this metal serves as a reference ground, and a capacitive impedance is generated between the antenna and the metal at a desired high frequency band of the antenna, and the resonance point of the antenna. The antenna characteristics are deteriorated by changing the gain efficiency and the radio characteristics are deteriorated, so that it is not possible to mount an electric circuit component covered with metal particularly near the antenna.

  Specifically, the antenna is typically mounted on the tip or side of the main body of a small wireless device, but a connector for an external interface, a side switch, or the like is often mounted on the tip or side of the main body. For example, the external interface connector is covered with metal sheet metal so as to wrap the connector outer shape from the viewpoint of improving the strength of fixing to the printed circuit board and preventing static electricity, and plugging it into the printed circuit board by soldering the metal sheet metal The signal terminal part of the external interface connector is exposed when interfacing with external devices, and even when the human body static electricity is applied, the static electricity is discharged to the metal sheet metal side. Thus, the discharge to the signal terminal portion is prevented.

  For this reason, when the external interface connector is mounted in the vicinity, such as under the antenna, the metal sheet metal covering the external interface connector exists as a metal conductor having a reference ground potential. An external interface connector or the like could not be mounted at such a location.

  In addition, such problems relating to deterioration of antenna characteristics and electrostatic breakdown are not limited to metal sheet metal that covers electrical circuit components, but are common to any component that is at least partially made of metal to be placed near the antenna. I can say that.

  By the way, although it is shown in the above-mentioned patent document 2 that the antenna gain is improved by using a coil component, this does not cut off the high-frequency current by the coil component, but there is no antenna from the circuit board with the antenna. The circuit board is actively energized, and there is a problem in high-density mounting in which an electric circuit component or the like, at least part of which is made of metal, is mounted under the antenna or the like. There is no recognition about the problem of changing the point and degrading the antenna characteristics, the problem of electrostatic breakdown, and the like, and the problem cannot be solved.

(the purpose)
The object of the present invention is to solve the above-mentioned problems, without deteriorating the antenna characteristics even when a part made of metal, such as an electric circuit part coated with metal, is mounted near the antenna. It is an object of the present invention to provide a small wireless device, a printed circuit board of a small wireless device, and a component mounting method that can improve mounting efficiency.

  Another object of the present invention is to secure a common reference potential and to operate an electric circuit in the DC band even when a component made of metal, such as an electric circuit component coated with metal, is mounted near the antenna. It is another object of the present invention to provide a small wireless device, a printed circuit board for a small wireless device, and a component mounting method that can prevent electrical components and electric circuits from being damaged by the application of static electricity.

  Another object of the present invention is that even when an external interface connector or side switch component is mounted near the antenna, a common reference potential can be secured, and the mounting efficiency can be improved without degrading the antenna characteristics. An object of the present invention is to provide a small wireless device capable of preventing destruction, a printed circuit board of the small wireless device, and a component mounting method.

  In the small wireless device of the present invention, an antenna (for example, 1 in FIGS. 1 and 6) is mounted on a main body, and a part (for example, 6 in FIGS. The grounding ground of the component is electrically divided from the reference ground to which the antenna is connected, and connected to each other by an inductance element (for example, 7 in FIGS. 1 and 7) that is open in a desired high frequency band. It is characterized by that. For example, the antenna is mounted on a copper foil pattern (for example, 101 in FIGS. 1 and 7) of a printed board serving as the reference ground inside the housing of the main body, and the component is a copper foil of the printed board serving as the ground ground. It is characterized by being mounted on a pattern (for example, 102 in FIGS. 1 and 7), and the antenna is mounted on the outside of the casing of the main body and the copper foil pattern (for example, FIG. 2) of the printed circuit board serving as the reference ground. 101), the component is mounted on a casing around the antenna, and is connected to a copper foil pattern (for example, 102 in FIG. 7) of the printed circuit board that serves as the ground ground.

  In the printed circuit board of the present invention, one of the electrically divided copper foil patterns is used as a reference ground for connecting the antenna, and the other copper foil pattern is disposed around the antenna, and at least a part of the ground ground is a metal ground. The copper foil patterns are connected to each other by an inductance element that is open in a desired high frequency band, the antenna is mounted on the outside of the main body casing, and the component is a casing around the antenna. It is characterized by being mounted on.

  According to another aspect of the present invention, there is provided a component mounting method for a small wireless device in which an antenna is arranged with one of electrically divided copper foil patterns as a reference ground, and at least a part connected to the other copper foil pattern is made of metal. The antenna characteristics and the electrostatic characteristics are improved by disposing the copper foil patterns around each other and connecting the two copper foil patterns to each other by an inductance element so as to be opened in a high frequency band and short-circuited in a low frequency band. The antenna is mounted on the outside of the housing of the main body, and the component is mounted on a housing around the antenna.

  The component is a component corresponding to an external interface connector or a side switch, and the antenna and the component are arranged at any one of four ends of the printed circuit board, and the antenna is an inverted F antenna. Configured as

  More specifically, for example, the inductance element 7 is inserted between the copper foil pattern 102 of the printed circuit board 100 on which the external interface connector 6 is mounted and the reference ground pattern 101 of the main body printed circuit board. In the desired high frequency band of the antenna, the metal sheet metal that covers the external interface connector 6 does not act as a reference ground potential by the inductance element 7 and can be regarded as a metal object that does not have an electrical potential. Can be reduced.

  As for the electric circuit operation, since the inductance element 7 acts as a zero impedance in a DC manner, there is no potential drop of the DC reference potential, a common reference potential can be secured, and the circuit operation of the external interface connector 6 operates normally.

  Further, when static electricity is applied, the static electricity is discharged to the metal sheet metal side and passes through the inductance element 7 to the reference ground pattern 101, so that the discharge to the signal terminal portion of the external interface connector 6 can be prevented. (Figure 1)

  According to the present invention, even if a component including a metal is mounted close to the periphery of the antenna so as to increase the mounting density of the components of the small wireless device, the ground for grounding the component and the reference for mounting the antenna of the main body are mounted. By electrically dividing the ground and connecting each other with an inductance element that is open in a desired high frequency band, it is possible to suppress the generation of capacitive impedance due to the above-mentioned components that are close to the antenna and prevent deterioration of the antenna characteristics In addition, even when static electricity is applied to the component, the inductance element that is short-circuited in a direct current can surely flow static electricity to the reference ground, and electrostatic breakdown and the like can be prevented. In other words, by electrically separating the grounding ground pattern for mounting the electric circuit parts covered with metal in the vicinity of the antenna and the reference ground pattern for mounting the antenna, and connecting the inductance element between both patterns, It is possible to improve the mounting density, improve the antenna characteristics and prevent electrostatic breakdown at the same time, and operate normally without voltage drop of the reference potential of the parts by the inductance element that acts as zero impedance in DC. .

  In particular, as with the built-in antenna, it is often placed at the tip or side of the housing, and even if an external interface connector or the like that can be placed at the same location when mounted at high density is placed under the antenna, Does not adversely affect the characteristics. In addition, the conductor part such as a metal sheet metal that covers the external interface connector is exposed to the outside of the housing at least during use. However, when static electricity is applied from the outside, the static electricity is transferred from the conductor part such as the metal sheet metal via the inductance element to the reference ground. It is possible to maintain the same level of static electricity resistance as before.

(Embodiment 1)
An embodiment of a small wireless device of the present invention will be described in detail with reference to a configuration example of a mobile phone.
(Description of configuration)
FIG. 1 is a diagram showing a configuration of a printed circuit board and a mounting component on the printed circuit board of the mobile phone according to the present embodiment. FIG. 2 is a diagram showing an electric circuit composed of mounted components on the printed board shown in FIG.

  The printed circuit board 100 uses a multilayer board or the like to be described later, and is formed with copper foil patterns 101 and 102 divided into two on the upper surface (surface layer) as a wiring and a ground ground. On the copper foil pattern, the antenna 1 and the antenna Various electric circuit components such as a matching circuit 2, a wireless communication circuit 3, a control circuit 4, an external interface circuit 5, an external interface connector 6, an inductance element 7, and a switch component 8 are mounted.

  In the example shown in FIG. 1, the copper foil pattern 101 occupying most of the printed circuit board 100 on which the antenna 1, the antenna matching circuit 2, the wireless communication circuit 3, the control circuit 4, the switch component 8, and the like are mounted, and the external interface connector 6 And an inductance element 7 connected (mounted) between the copper foil pattern 101 and a copper foil pattern 102 on the end side of the printed circuit board 100 having a shape entering the copper foil pattern 101. Here, the antenna 1 is composed of a metal sheet metal or the like, and has a feeding point with the pattern as a reference ground on the copper foil pattern 101, and the copper foil pattern 102 and the external interface connector 6 are disposed below the antenna sheet metal. Located and achieves high-density mounting.

  The electric circuit shown in FIG. 2 is configured by wiring with a copper foil pattern on the printed circuit board 100. As can be seen from the figure, only the external interface connector 6 is grounded via an inductance element 7 with respect to a ground ground of another circuit or the like. The printed circuit board 100 is housed in a housing case (not shown) and covered with a housing cover (not shown), thereby constituting the main body of the mobile phone as a whole. The detailed configuration and function of each part are as follows.

  The antenna 1 is mounted on the printed circuit board 100 directly or via a connection terminal, a connection connector, or the like at the end of a metallic sheet metal. In small wireless devices in recent years, built-in antennas have become mainstream, and inverted F-shaped antennas that can be configured on a printed circuit board are often used.

  The external interface connector 6 is provided around the casing for connecting an external peripheral device and a mobile phone, and these are for an external connector (not shown) when not in use in order to prevent external appearance and design of static electricity. The external interface connector 6 is covered with a cover so as not to be exposed to the outside.

  In general, a mobile phone includes an earphone / microphone connector, a data communication connector, and a charging connector as the external interface connector 6. In addition, as an external memory, an external memory slot for inserting a miniSD or Memorystick is provided. In the present invention, the external memory slot is also handled as the external interface connector 6.

  The control circuit 4 includes a CPU and a memory, and controls the operation of the mobile phone. When performing wireless communication with the base station, the control circuit 4 controls the wireless communication circuit 3 to propagate radio waves of communication data via the antenna 1. The control circuit 4 monitors the switch component 8 and controls the operation of the mobile phone according to the operation when the mobile phone is operated by the switch component 8. The control circuit 4 monitors and controls the external interface circuit 5. When an external device is connected to the external interface connector 6, the control circuit 4 controls the operation according to the external device.

  Note that the mobile phone actually includes electric circuit components such as a display unit, a microphone, a speaker, and a vibrator, but is omitted in the description of the present embodiment.

(Description of operation)
Next, the operation of the embodiment of the present invention will be described.
The external interface connector 6 of the mobile phone is mounted on one of the four side edges of the printed circuit board 100 to perform interface communication with an external connection device. The external interface connector 6 includes a housing cover (not shown) and a housing case. Even when incorporated in the body, the external interface connector 6 is exposed from the side of the housing. The metal sheet metal and the ground terminal covering the external interface connector 6 are soldered to the copper foil pattern 102 on the printed board 100. Here, the copper foil pattern 102 is electrically separated from the reference ground pattern 101 of the electric circuit of the mobile phone as described above, and is connected by the inductance element 7.

  The antenna 1 is made of a metal sheet metal or the like, and is mounted so that a feeding point is provided on the copper foil pattern 102 beside the external interface connector 6 and is disposed directly above the external interface connector 6. The ground of the antenna 1 is connected to the reference ground pattern 101 of the electric circuit of the mobile phone.

  FIG. 3 is a view showing a cross section of the printed circuit board taken along the alternate long and short dash line Aa shown in FIG. The configuration of the printed circuit board 100 will be described using a four-layer printed circuit board as an example.

  In FIG. 3, a wireless communication circuit 3, a control circuit 4, an external interface connector 6, and an inductance element 7 are mounted on a printed board 100. Although not shown in FIG. 3, the antenna 1, the antenna matching circuit 2, the external interface circuit 5, and the switch component 8 shown in FIG. 1 are also mounted on the printed board 100. The reference ground pattern 101 electrically connects the surface layer and the inner layer of the printed circuit board 100 with an inner layer reference ground pattern 101a and a reference ground pattern Via (via) 101b. The copper foil pattern 102 electrically connects the surface layer and the inner layer of the printed circuit board 100 with the inner layer copper foil pattern 102a and the copper foil pattern Via 102b.

  As shown in FIG. 3, the reference ground pattern 101 of this embodiment and the copper foil pattern 102 to which the external interface connector 6 is soldered are also separated on the substrate surface and the copper foil on the inner layer of the substrate. Are mounted between the copper foil pattern 102 under the divided external interface connector 6 and the reference ground pattern 101 of the electric circuit of the mobile phone. Due to the inductance element 7, the copper foil pattern 102 and the reference ground pattern 101 under the external interface connector 6 act as an open pattern in a desired high frequency band (radio frequency band) of the antenna 1, and as a short pattern in the DC band. Works.

  FIG. 4 is a diagram showing antenna impedance characteristics when the copper foil pattern 102 under the external interface connector 6 and the reference ground pattern 101 of the electric circuit of the small wireless device are connected by a resistance element having a resistance value = 0Ω.

  FIG. 5 is a diagram showing antenna impedance characteristics when the copper foil pattern 102 under the external interface connector 6 and the reference ground pattern 101 of the electric circuit of the small wireless device are connected by the inductance element 7.

  The desired characteristics of the antenna impedance shown in FIGS. 4 and 5 are, for example, that the desired band of the antenna is 2.4 GHz to 2.6 GHz (between Δ mark 1 and Δ mark 3 in the figure), and one antenna band within the desired band. This characteristic requires a resonance point.

  In FIG. 4, resonance points A and B exist in a desired antenna band of 2.4 GHz to 2.6 GHz. The resonance point A is obtained by matching the resonance point to a desired band by the antenna 1 and the antenna matching circuit 2. The resonance point B is not intended and is an unnecessary resonance point appearing on the antenna impedance characteristics due to the influence of a component mounted near the antenna, and the resonance point B exists in a desired antenna band. Thus, the radiation efficiency of the antenna is lowered, and the antenna characteristics are deteriorated.

  That is, in FIG. 4, the copper foil pattern 102 under the external interface connector 6 has the same potential as the reference ground pattern 101, and the metal sheet metal covering the external interface connector 6 has the same potential as the reference ground. A large capacitive impedance is generated between the antenna 1 and the metal sheet metal of the external interface connector 6 in the band, and an unnecessary resonance point B exists in a desired frequency band, which causes deterioration of the antenna characteristics. Yes.

  In FIG. 5, only the resonance point A exists in the desired antenna band 2.4 GHz to 2.6 GHz, and the resonance point B is greatly deviated from the desired antenna band 2.4 GHz to 2.6 GHz. (Existing at about 3.3 GHz) In a desired antenna band of 2.4 GHz to 2.6 GHz, good antenna characteristics can be obtained without reducing the radiation efficiency.

  That is, in FIG. 5, since the copper foil pattern 102 under the external interface connector 6 does not have the same potential as the reference ground pattern 101, the metal sheet metal of the external interface connector 6 does not have the same potential as the reference ground. , The capacitive impedance between the antenna 1 and the metal plate of the external interface connector 6 can be reduced, unnecessary resonance points can be removed from the desired frequency band, and no components are mounted near the antenna. Antenna characteristics equivalent to the above can be obtained.

  Thus, in the present invention, since the inductance element 7 is inserted between the copper foil pattern 102 under the external interface connector 6 and the reference ground pattern 101, the metal of the external interface connector 6 is used in the frequency band transmitted and received by the antenna. Since the sheet metal does not operate as the reference ground potential, the antenna characteristics are not deteriorated.

  Further, since the copper foil pattern 102 and the metal sheet metal under the external interface connector 6 are grounded to the reference ground pattern 101 via the inductance element 7, they have the same potential as a DC electric circuit, and are common reference in a low frequency band. Potential is secured.

  Further, the external interface connector 6 is normally covered with an external connector cover (not shown) so as not to be exposed to the outside. However, the external interface cover 6 is opened during use, and the external interface connector 6 is exposed. Is easily applied.

  However, since the copper foil pattern 102 and the metal sheet metal under the external interface connector 6 are grounded to the reference ground pattern 101 via the inductance element 7, the applied static electricity flows to the reference ground with a low impedance. Thus, it is possible to prevent static electricity from flowing into the external interface circuit 5 from the terminal portion 6 and prevent the circuit from being damaged by static electricity.

  In the above configuration example, the external interface connector 6 has been described as an example of the component mounted under the antenna 1, but the switch component 8 can also be applied as an object of the present invention in a cellular phone. Hereinafter, an example in which the switch component is mounted on the copper foil pattern under the antenna 1 will be described.

  The number of mobile phones equipped with side switches on the side of the main body is also increasing, and the switch parts 8 constituting the side switches are not exposed from the main body, but the case fits on the main body structure of the side switch portion when operated by the user. It is a part where static electricity easily enters from the gap. In particular, the switch component 8 used for the side switch has a durability against pressing of the switch, and like the external interface connector 6, part or the periphery of the component is covered with a metal sheet metal, and the metal sheet metal is applied to the copper on the printed circuit board 100. Soldering to the foil pattern. Conventionally, since the copper foil pattern on the printed circuit board 100 is integrated with the reference ground pattern 101, it cannot be mounted near the antenna 1 for the same reason as the external interface connector 6 described above.

  Also for the switch component 8 constituting the side switch, the present invention is applied, and the soldering of the metal sheet metal is not directly connected to the reference ground pattern 101 but separated from the reference ground pattern 101 and connected via the inductance element 7. Connect to the copper foil pattern 102. Accordingly, the switch 1 operates normally as a switch without affecting the antenna 1 and passes static electricity from the metal sheet metal of the switch component 8 through the inductance element 7 to the reference ground even when static electricity is applied. Static electricity can be prevented from flowing into the control circuit 4 being controlled.

(Embodiment 2)
In the first embodiment, an example in which an antenna and electrical components are mounted inside the main body has been described. However, as a second embodiment of the present invention, a cellular phone applied to components such as an antenna and a metal sheet metal mounted outside the main body. An example will be described.

FIG. 6 is a diagram showing an appearance of a main body of a mobile phone according to another embodiment of the present invention.
The casing of the cellular phone is configured by fitting the casing cover 21 and the casing case 22, and a printed circuit board is accommodated therein, so that the main body of the cellular phone is configured as a whole. Here, in addition to the antenna 1, the camera window 9 a, and the display unit window 13 a, a metal sheet metal 12 is attached to the housing cover 21. In particular, the antenna 1 is composed of a conductive sheet metal, a metal rod, or the like, and is provided so that the tip is exposed to the outside of the main body. Arranged nearby, the strength of the main body is ensured, the camera 9 and the display unit 13 are reinforced, and the appearance is improved.

  FIG. 7 is a diagram showing the configuration of the printed circuit board and the mounted components on the printed circuit board. FIG. 8 is a diagram showing an electric circuit constituted by mounting components on the printed board shown in FIG.

  The printed circuit board 100 of the cellular phone has various electrical devices such as an antenna matching circuit 2, a wireless communication circuit 3, a control circuit 4, an impedance element 7, a camera 9, an antenna connection connector 10, a metal sheet metal connection terminal 11, a display unit 13, and the like. Although circuit components are mounted, the pattern of the printed circuit board 100 has an opening shape (opening) formed in the reference ground pattern 101, and a copper foil pattern 102 that connects the metal sheet metal connection terminals 11 is formed in the opening. The impedance element 7 is connected between both patterns. The electric circuit shown in FIG. 8 is configured by each electric circuit component and the wiring pattern of the copper foil on the printed board. As can be seen from FIG. 8, the metal sheet metal 12 is connected to the reference ground pattern 101 via the metal sheet metal connection terminal 11 and the impedance element 7.

  In the configuration of the cellular phone, since the metal sheet metal 12 is mounted outside the housing case 21, static electricity is easily applied. When static electricity is applied, the camera 9 and the display unit 13 near or in contact with the metal sheet metal 12. There is a risk of destroying. When the metal sheet metal 12 is directly connected to the reference ground of the printed circuit board to protect the camera 9 and the display unit 13 when static electricity is applied, the metal sheet metal 12 becomes a potential of the reference ground even at high frequencies, and the antenna 1 and the metal Since a capacitive impedance with the sheet metal 12 is formed, an unnecessary resonance point is generated in a specific high frequency band of the antenna, and the antenna characteristics are deteriorated.

  In order to solve this problem, the metal plate 12 mounted on the housing cover 21 and the reference ground pattern 101 of the printed circuit board 100 are separated in a desired high frequency band. Specifically, as shown in FIG. 7, the copper foil pattern under the metal sheet metal connection terminal 11 mounted on the printed circuit board 100 is divided from the reference ground to form a copper foil pattern 102, which is electrically connected to the reference ground pattern 101. The copper foil pattern 102 and the reference ground pattern 101 are separated and connected by an inductance element 7.

  Thereby, in the inductance element 7, the metal sheet metal 12 mounted on the housing cover 21 in the desired high frequency band of the antenna and the reference ground pattern 101 of the printed circuit board 100 act as an open pattern, and act as a short pattern in the DC band. .

  That is, in the high frequency band transmitted and received by the antenna, the metal sheet metal 12 mounted on the housing cover 21 does not have the potential of the reference ground, but the capacitive impedance between the antenna 1 and the metal sheet metal 12 mounted on the housing cover 21. Thus, it is possible to secure the same antenna characteristics as when there is no metal sheet near the antenna, and it is possible to secure a common reference potential in the low frequency band.

  The metal sheet metal 12 mounted on the housing cover 21 is easily applied with static electricity, but is grounded to the reference ground via the inductance element 7, and thus the discharged static electricity flows to the reference ground. Static electricity can be prevented from flowing from the metal sheet metal 12 mounted to the camera 9 mounted under the metal sheet metal 12 and the display unit 13 mounted beside the metal sheet metal 12.

  In the second embodiment, the example of the metal sheet metal 12 has been described as the metal part. However, the present invention is not limited to the metal sheet metal but can be applied to metal parts such as decorative parts obtained by vapor deposition and plating of metal.

  In the above embodiment, the ground pattern is divided into the copper foil pattern 102 and the reference ground pattern 101 by one printed circuit board, and each pattern is connected by an inductance element. However, two or more printed circuit boards are used. In a small wireless device configured to electrically connect two printed circuit boards, one of which is formed of the copper foil pattern 102 and the other of the reference ground pattern 101, the printed circuit boards are connected via the inductance element. It can be configured as follows.

  Further, when mounting several types of antennas on a printed circuit board, the copper foil pattern 102 is separated for each desired frequency, and inductance elements having inductance values corresponding to the respective frequencies are mounted for each frequency. Also good. Furthermore, the reference ground pattern 101 may be composed of two or more types according to the configuration of the electric circuit, and the divided copper foil pattern and the reference ground pattern can be connected by an inductance element.

  Furthermore, the inductance element 7 can be formed as a high-frequency pattern having a desired inductance characteristic formed by a copper foil pattern on a printed board instead of being constituted by an electric component such as a coil.

  A small wireless device in which an antenna is mounted inside or outside a main body, such as a mobile phone, PHS (Personal Handyphone System), PDA (Personal Data Assistance, Personal Digital Assistants).

It is a figure which shows the structure of the printed circuit board of the mobile telephone based on 1st Embodiment which concerns on this invention, and the mounting components on a printed circuit board. It is a figure which shows the electric circuit comprised by the mounting components on the printed circuit board shown in FIG. It is a figure which shows the cross section which cut the printed circuit board between the dashed-dotted line Aa shown in FIG. The configuration of the printed board will be described by taking a four-layer printed board as an example. It is a figure which shows the characteristic of the antenna impedance at the time of connecting between the copper foil pattern under an external interface connector, and the reference | standard ground pattern of the electric circuit of a small radio | wireless apparatus with the resistance element of resistance value = 0ohm. It is a figure which shows the characteristic of the antenna impedance at the time of connecting between the copper foil pattern under an external interface connector, and the reference | standard ground pattern of the electric circuit of a small radio | wireless apparatus with an inductance element. It is a figure which shows the main body external appearance of the mobile telephone of 2nd Embodiment in this invention. It is a figure which shows the structure of the mounting component on a printed circuit board and a printed circuit board. It is a figure which shows the electric circuit comprised by the mounting components on the printed circuit board shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna 2 Antenna matching circuit 3 Wireless communication circuit 4 Control circuit 5 External interface circuit 6 External interface connector 7 Impedance element 8 Switch circuit 9 Camera 9a Camera window 10 Antenna connection terminal (power supply terminal)
DESCRIPTION OF SYMBOLS 11 Metal sheet metal connector 12 Metal sheet metal 13 Display part 13a Display part window 21 Case cover 22 Case case 100 Printed circuit board 101 Reference ground pattern 101a Inner layer reference ground pattern 101b Reference ground pattern Via
102 Copper foil pattern 102a Inner layer copper foil pattern 102b Copper foil pattern Via

Claims (22)

An antenna is mounted on the main body, and at least a part made of metal is mounted around the antenna, and the grounding ground of the component is electrically divided from the reference ground of the antenna, and the grounding ground and the reference ground Are connected to each other by an inductance element that is open in a desired high frequency band. The antenna is mounted on a copper foil pattern of a printed board serving as the reference ground inside a housing of a main body, and the component is mounted on a copper foil pattern of a printed board serving as the ground ground. The small wireless device according to 1. The small wireless device according to claim 1, wherein the antenna is mounted outside a housing of the main body, and the component is mounted on a housing around the antenna. The small wireless device according to claim 1 or 2, wherein the component is a component corresponding to an external interface connector. The small wireless device according to claim 1, wherein the component is a component corresponding to a side switch. The small wireless device according to any one of claims 1, 2, 4, and 5, wherein the antenna and the component are mounted on any one of four ends of a printed circuit board. The small wireless device according to any one of claims 1, 2, 4, 5 and 6, wherein the antenna is configured as an inverted F-type antenna. The small wireless device according to any one of claims 1 to 7, wherein the small wireless device is applied to a mobile phone terminal or a PHS terminal. One of the electrically divided copper foil patterns is used as a reference ground for connecting the antenna, and the other copper foil pattern is used as a ground ground for a part made of metal at least partially arranged around the antenna. A printed circuit board for a small wireless device, wherein the printed circuit boards are connected to each other by an inductance element that is open in a desired high frequency band. The printed circuit board according to claim 9, wherein the antenna is mounted outside a housing of the main body, and the component is mounted on a housing around the antenna. The printed circuit board according to claim 9, wherein the component is a component corresponding to an external interface connector. The printed circuit board according to claim 9, wherein the component is a component corresponding to a side switch. 13. The printed circuit board according to claim 9, wherein the antenna and the component are arranged at any one end of the printed circuit board. The printed circuit board according to claim 9, 11, 12, or 13, wherein the antenna is configured as an inverted F-type antenna. The printed circuit board according to claim 9, wherein the small wireless device is a mobile phone terminal or a PHS terminal. An antenna is placed using one of the electrically divided copper foil patterns as a reference ground, and a part of the metal that is connected to the other copper foil pattern is made of metal. A component mounting method for a small wireless device characterized in that antenna characteristics and electrostatic characteristics are improved by connecting to each other by an element, opening in a high frequency band, and short-circuiting in a low frequency band. 17. The component mounting method for a small wireless device according to claim 16, wherein the antenna is mounted outside a housing of the main body, and the component is mounted on a housing around the antenna. 17. The component mounting method for a small wireless device according to claim 16, wherein the component is a component corresponding to an external interface connector. 17. The component mounting method for a small wireless device according to claim 16, wherein the component is a component corresponding to a side switch. 20. The component mounting method for a small wireless device according to claim 16, 18 or 19, wherein the antenna and the component are arranged at any one end of the printed circuit board. 21. The component mounting method of the small wireless device according to claim 16, wherein the antenna is configured as an inverted F-type antenna. The component mounting method for a small wireless device according to any one of claims 16 to 21, wherein the small wireless device is a mobile phone terminal or a PHS terminal.

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