JP2018107630A - Electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus with a new structure that contributes to miniaturization.SOLUTION: An electronic apparatus comprises: a first substrate 12A; a second substrate 12B; and a resin housing 11. The resin housing 11 is formed with wiring that includes a signal line for electrically connecting the first substrate 12A and the second substrate 12B. The wiring formed on the resin housing may include the ground. The wiring may further include a connection member that connects at least one of the first substrate 12A and second substrate 12B and the signal line, and a ground member that connects at least one of the first substrate 12A and second substrate 12B and the ground.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic device.

  In recent years, electronic devices such as smartphones and tablet terminals have been made thinner in the thickness direction and smaller in the surface direction different from the thickness direction (hereinafter collectively referred to as miniaturization). As an example, a technique is known in which the size of the main circuit board in the surface direction is about half that of the casing, and the thickness of the casing in a region where the main circuit board is not disposed is reduced. Here, the main circuit board is the largest circuit board among the circuit boards inside the housing.

  Along with miniaturization of the main circuit board, a portable wireless device having a wireless communication function among electronic devices may be designed so that the antenna for wireless communication is as far as possible from the main circuit board. In such a case, in order to electrically connect the main circuit board and the antenna, connection by a coaxial cable is generally performed (for example, Patent Document 1).

JP 2010-258826 A

  Here, when the main circuit board and the antenna are connected by a coaxial cable, a space for passing the coaxial cable is required. In addition, an additional member for fixing the coaxial cable may be required. In other words, when connecting with a coaxial cable, there is a certain restriction on the downsizing of the housing. Therefore, there has been a demand for a new structure that contributes to miniaturization instead of a structure using a coaxial cable.

  An object of the present invention made in view of such circumstances is to provide an electronic apparatus having a new structure that contributes to downsizing.

  An electronic apparatus according to an embodiment of the present invention includes a first substrate, a second substrate, and a resin casing, and the resin casing electrically connects the first substrate and the second substrate. A wiring including a signal line for connection is formed.

  According to one embodiment of the present invention, it is possible to provide an electronic apparatus having a new structure that enables further miniaturization.

It is a schematic internal structure figure of the electronic device which concerns on one Embodiment. It is a schematic sectional drawing of the thickness direction of the electronic device which concerns on one Embodiment. It is a figure which illustrates the connection of the board | substrate and resin housing | casing of the electronic device which concern on one Embodiment. It is a figure which illustrates the passage characteristic of the signal at the time of using one ground pin. It is a figure which illustrates the passage characteristic of the signal at the time of using two ground pins. It is a schematic sectional drawing of the thickness direction of the electronic device which concerns on another embodiment. It is a schematic sectional drawing of the thickness direction of the electronic device of a comparative example.

[First Embodiment]
(Schematic internal structure of electronic equipment)
The electronic device 1 of one embodiment shown in FIG. 1 is a smartphone. As an alternative example, the electronic device 1 may be a portable device (portable wireless device) having a wireless communication function other than a smartphone. For example, the electronic device 1 may be a mobile phone terminal, a Fablet, a tablet PC, a feature phone, a PDA, a remote control terminal, a portable music player, a game machine, an electronic book reader, or the like.

  FIG. 1 is a schematic internal structure diagram schematically showing components incorporated in the electronic apparatus 1. The electronic device 1 includes a front cover 15, a display 14, a battery 13, a first substrate 12 </ b> A, a second substrate 12 </ b> B, a resin housing 11, and a rear cover 10. In the present embodiment, the resin casing 11 includes three separated parts (a resin casing 11A, a resin casing 11B, and a resin casing 11C). Further, in FIG. 1, the front cover 15, the first substrate 12A, and the second substrate 12B are drawn to be transparent so as to allow the components on the back surface to pass therethrough. However, in general, a part of the front cover 15, the first substrate 12A, and the second substrate 12B are opaque.

  As shown in FIG. 1, coordinate axes corresponding to the configuration of the electronic device 1 are determined. When the electronic apparatus 1 is used, the depth direction for the user is the z-axis direction. In another expression, the thickness direction of the electronic device 1 is the z-axis direction. The direction from the front cover 15 to the rear cover 10 of the electronic device 1 is the z-axis positive direction. Further, the longitudinal direction and the lateral direction of the main surface of the electronic device 1 are the y-axis direction and the x-axis direction, respectively. Along the longitudinal direction of the electronic device 1, the direction toward the end provided with a speaker that emits sound during a call is the positive y-axis direction. The direction shown in FIG. 1 is the x-axis positive direction so as to constitute a right-handed coordinate system. Here, the y-axis direction is particularly referred to as a main surface direction.

  The front cover 15 constitutes the outer peripheral portion of the front surface of the electronic device 1. The front cover 15 is made of resin, for example. For example, the front cover 15 may include a hole (space) in a portion that transmits sound from a speaker and a portion that corresponds to a physical button used by the user. Further, the front cover 15 may be transparent at a portion corresponding to the display 14 or may be provided with a hole (space). The front cover 15 may have a metal part. For example, the front cover 15 may be formed by insert molding a resin into a metal.

  The display 14 displays a screen. The display 14 may be, for example, a liquid crystal display. The display 14 may be an organic EL panel (Organic Electro-Luminescence Panel) or an inorganic EL panel (Inorganic Electro-Luminescence Panel). In the present embodiment, the display 14 is a touch screen display. The touch screen display detects a contact of a finger or a stylus pen and specifies the contact position.

  The battery 13 supplies power to the electronic device 1. The battery 13 is a lithium ion battery, for example. As another example, the battery 13 may be a nickel cadmium battery or a nickel metal hydride battery.

  The first substrate 12 </ b> A and the second substrate 12 </ b> B fix (mount) electronic components used in the electronic circuit in order to realize various functions of the electronic device 1. In the present embodiment, the first substrate 12A is a main circuit substrate that is larger than the second substrate 12B. Moreover, although the electronic device 1 according to the present embodiment includes the two substrates, the first substrate 12A and the second substrate 12B, it may include three or more substrates.

  The resin casing 11 (resin casing 11A, resin casing 11B, and resin casing 11C) is a resin casing. The resin casing 11 is formed with wiring including a signal line and a ground for electrically connecting the first substrate 12A and the second substrate 12B. In the present embodiment, the signal line transmits a high frequency signal (hereinafter also referred to as an RF signal). The wiring is formed by, for example, LDS (Laser Direct Structuring). FIG. 1 illustrates a signal line (RF signal line 23) for transmitting an RF signal formed in the resin casing 11C. The RF signal line of the first substrate 12A is electrically connected to the RF signal line 23 via the pin 16C. The RF signal line of the second substrate 12B is electrically connected to the RF signal line 23 via the pin 16D. That is, the first substrate 12A is electrically connected to the second substrate 12B by the RF signal line 23 formed in the resin casing 11C. Here, the wiring is formed not only in the resin casing 11C but also in the resin casing 11A and the resin casing 11B. In addition, a first antenna 21A (see FIG. 2) is formed on the surface in the z-axis positive direction in the resin casing 11A located at the end in the y-axis negative direction of the electronic device 1. Similarly, a second antenna 21B (see FIG. 2) is formed on the surface in the z-axis positive direction on the resin casing 11B located at the end in the y-axis positive direction of the electronic device 1.

  The rear cover 10 constitutes the outer peripheral portion of the back surface of the electronic device 1. The rear cover 10 is made of resin, for example. The rear cover 10 may be subjected to surface processing so that the user can easily grip it. The rear cover 10 may have a metal part. For example, the rear cover 10 may be formed by insert molding a metal into a resin.

  Further, the pins 16A, 16B, 16C, 16D, 17C, 17D, 18C and 18D in FIG. 1 have conductivity. The pin 16A is a conductive pin for transmitting an RF signal between the first substrate 12A and the resin casing 11A. The pin 16B is a conductive pin for transmitting an RF signal between the second substrate 12B and the resin casing 11B. The pin 16C is a conductive pin for transmitting an RF signal between the first substrate 12A and the resin casing 11C. The pin 16D is a conductive pin for transmitting an RF signal between the second substrate 12B and the resin casing 11C. The pins 17C and 18C are used to connect the ground of the first substrate 12A and the ground of the resin housing 11C. The pins 17D and 18D are used to connect the ground of the second substrate 12B and the ground of the resin casing 11C.

  Here, FIG. 1 schematically shows components built in the electronic apparatus 1. The electronic device 1 may not include all of the components shown in FIG. Further, the electronic device 1 may include components not shown in FIG.

(Cross-sectional structure of electronic equipment)
FIG. 2 is a schematic cross-sectional view of the electronic device 1 in the thickness direction (z-axis direction). FIG. 2 shows a cross section of the electronic device 1 cut to include the pins 16A, 16B, 16C, and 16D. FIG. 2 shows a cross section of a portion excluding the front cover 15 and the rear cover 10. 2 is the back side of the electronic device 1, and the lower side of the paper is the front side of the electronic device 1.

  Here, the first antenna 21A formed on the resin casing 11A and the second antenna 21B formed on the resin casing 11B are used to realize the wireless communication function of the electronic device 1 that is a smartphone. For example, the first antenna 21A and the second antenna 21B may be different from each other in at least one of a frequency band of a radio signal to be handled and a radio communication standard. As another example, the first antenna 21A and the second antenna 21B may constitute a diversity antenna.

  The processor 22 is an IC for wireless communication. The processor 22 performs various types of signal processing on signals transmitted and received via the first antenna 21A and the second antenna 21B, and realizes a function (for example, a call function, a data transmission / reception function, etc.) as a smartphone of the electronic device 1. The processor 22 is electrically connected to the pins 16A and 16C via an RF signal line formed on the first substrate 12A. Further, the pin 16D and the pin 16B are electrically connected by an RF signal line formed on the second substrate 12B. The processor 22 is electrically connected to the pins 17C and 18C through the ground formed on the first substrate 12A. The pins 17D and 18D are electrically connected via a ground formed on the second substrate 12B.

  The pin 16A is electrically connected to the first antenna 21A through a through hole formed in the resin casing 11A. The pin 16B is electrically connected to the second antenna 21B through a through hole formed in the resin casing 11B. Other elements shown in FIG. 2 are the same as those in FIG. The same elements as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

  Here, with the recent demand for miniaturization, antennas (first antenna 21A and second antenna 21B) and substrates (first substrate 12A and second substrate 12B) on which electronic components are mounted are arranged in the thickness direction. In many cases, it is difficult to prevent overlap in the z-axis direction. In the present embodiment, the antenna overlaps at least one of the first substrate 12A and the second substrate 12B in the thickness direction of the electronic device 1. More specifically, the second antenna 21B and the second substrate 12B overlap in the z-axis direction. The second substrate 12B needs to be spaced apart from the second antenna 21B in the z-axis direction in order to avoid interference with the electronic component to be mounted. And the pin 16B has the length of the z-axis direction corresponding to a fixed space | interval.

  On the other hand, the first antenna 21 </ b> A and the first substrate 12 </ b> A do not substantially overlap in the thickness direction of the electronic device 1. Therefore, the first substrate 12A can be brought closer to the first antenna 21A than the second substrate 12B. The length of the pin 16A in the z-axis direction is shorter than that of the pin 16B. As shown in FIG. 2, the distance between the first substrate 12 </ b> A and the display 14 in the z-axis direction is wider than the distance between the second substrate 12 </ b> B and the display 14 in the z-axis direction. By disposing the battery 13 between the first substrate 12A and the display 14, the thickness of the electronic device 1 can be suppressed. As shown in FIG. 2, the thickness from the display 14 of the electronic device 1 to the antenna (the first antenna 21A and the second antenna 21B) is t1.

(Comparative example)
Here, with reference to FIG. 7, the effect of downsizing in the thickness direction of the electronic device 1 according to the present embodiment will be described while showing a schematic cross-sectional view in the thickness direction of the electronic device of the comparative example.

  As shown in FIG. 7, the electronic device of the comparative example includes one substrate 12C. The substrate 12C corresponds to a combination of the first substrate 12A and the second substrate 12B of the electronic device 1 according to this embodiment. Since the substrate 12C overlaps with the second antenna 21B in the z-axis direction, the substrate 12C needs to be spaced apart from the second antenna 21B in the z-axis direction. And since the board | substrate 12C is one and is not isolate | separated, it arrange | positions with the 1st antenna 21A at a fixed space | interval. As shown in FIG. 7, the substrate 12 </ b> C is connected not only to the second antenna 21 </ b> B but also to the first antenna 21 </ b> A with pins 16. Here, the length of the pin 16 in the z-axis direction is equal to the length of the pin 16B of the electronic device 1 according to the present embodiment in the z-axis direction.

  In the electronic device of the comparative example, the battery 13 is disposed between the substrate 12 </ b> C and the display 14. The thickness from the display 14 of the electronic device of the comparative example to the antenna (the first antenna 21A and the second antenna 21B) is t0. The thickness t0 corresponds to the thickness when the battery 13 is disposed between the second substrate 12B and the display 14 in the electronic apparatus 1 according to the present embodiment. Therefore, the thickness t1 of the electronic device 1 according to the present embodiment is smaller than the thickness t0 of the electronic device of the comparative example.

  Here, with reference to FIG. 2 again, the electronic apparatus 1 according to the present embodiment will be described. As described above, the electronic apparatus 1 according to the present embodiment includes a plurality of substrates (first substrate 12A and second substrate 12B), and at least one substrate (first substrate 12A) is an antenna in the thickness direction of the electronic device 1. Does not overlap. And the battery 13 is arrange | positioned so that it may overlap with the board | substrate (1st board | substrate 12A) which does not overlap with an antenna in the thickness direction of the electronic device 1. FIG. With this structure, it is possible to reduce the size as compared with the electronic device of the comparative example. Here, since the electronic device 1 includes a plurality of substrates (the first substrate 12A and the second substrate 12B), wiring for electrically connecting the substrates is necessary. As described above, the electronic device 1 forms wiring on the resin casing 11C in order to electrically connect the first substrate 12A and the second substrate 12B. By using the wiring formed in the resin casing 11C, the electronic device 1 does not require a space for passing the coaxial cable and an additional member. As described above, the electronic apparatus 1 according to the present embodiment contributes to downsizing.

(Pin arrangement)
FIG. 3 is an enlarged perspective view showing the connection between the first substrate 12A and the resin casing 11C of the electronic apparatus 1 according to the present embodiment. The electronic device 1 uses pins 16A to 16D, 17C to 17D, and 18C to 18D to connect the first substrate 12A or the second substrate 12B and the resin casing 11 (see FIG. 1). These pins are arranged as a set of three pins as in the example of pins 16C, 17C and 18C in FIG. That is, the electronic device 1 includes connection members (pins 16A to 16D) that connect at least one RF signal line of the first substrate 12A and the second substrate 12B and the RF signal line of the resin housing 11. In addition, the electronic device 1 connects at least one ground of the first substrate 12A and the second substrate 12B and the ground of the resin housing 11 and has two grounds arranged with a connection member (pins 16C to 16D) interposed therebetween. Members (pins 17C to 17D and 18C to 18D). The configurations of the connecting member and the ground member will be described below. Here, as shown in FIG. 3, the width of the substrate (the length of the first substrate 12A in the x-axis direction in the example of FIG. 3) is WS.

  The pin 16A shown in FIG. 3 is a connection member that transmits an RF signal. A ground member (ground pin) having a ground potential may be disposed near the RF signal connection member. This is because the impedance change in the RF signal line is reduced to reduce the reflection loss, and the power leaked into the air by the ground member is suppressed. That is, by arranging the grounding member near the RF signal connecting member, it is possible to expect a reduction in the RF signal passing loss. Here, it is preferable that the grounding member is disposed closer to the connection member.

  FIG. 4 is a diagram illustrating RF signal pass characteristics when one ground member having a ground potential is disposed near the RF signal connection member. The RF signal connection member and the ground member are arranged side by side in the width direction of the substrate (in the example of FIG. 3, the direction of WS). The vertical axis in FIG. 4 represents the transmission coefficient. The horizontal axis indicates the frequency of the high frequency signal. As shown in FIG. 4, a passage loss depending on WS, which is the width of the substrate, is seen at a frequency of 1500 MHz or higher that can be used in a smartphone. In the example of FIG. 4, when a substrate with WS = 60 mm is used, there is a large passage loss that peaks at a frequency near 2000 MHz. Further, when a substrate with WS = 48 mm is used, there is a large passage loss that takes a peak at a frequency near 2500 MHz. That is, when one grounding member is arranged, a singular point is generated according to WS which is the width of the substrate. This singular point is thought to be due to an increase in loss due to the parallel plate mode resonance occurring in the width direction of the substrate.

  FIG. 5 is a diagram illustrating RF signal pass characteristics when two ground members having a ground potential are arranged near the RF signal connection member. The RF signal connection member and the ground member are arranged side by side in the width direction of the substrate (in the example of FIG. 3, the direction of WS). The two ground members are arranged with an RF signal connection member interposed therebetween. In FIG. 5, the vertical axis represents the transmission coefficient. The horizontal axis represents the frequency of the RF signal. As shown in FIG. 5, when two ground members are arranged, singular points corresponding to WS do not occur at all frequencies. This is presumably because resonance does not occur by arranging grounding members at both ends of the RF signal connecting member.

  The electronic device 1 according to the present embodiment is configured to include two grounding members (pins 17C to 17D and 18C to 18D) that are arranged with a connection member (pins 16C to 16D) interposed therebetween. Therefore, regardless of the width of the substrate (the first substrate 12A or the second substrate 12B) to which the connecting member and the ground member are connected, there is no abrupt transmission loss (singular point) of the RF signal depending on the frequency. That is, the electronic device 1 according to the present embodiment can ensure a stable pass characteristic of a high-frequency signal.

[Second Embodiment]
An electronic apparatus 1 according to the second embodiment will be described with reference to FIG. In the present embodiment, the electronic device 1 can be further reduced in size by the cross-sectional structure described below.

(Cross-sectional structure of electronic equipment)
FIG. 6 is a schematic cross-sectional view in the thickness direction (z-axis direction) of the electronic apparatus 1 according to the present embodiment. FIG. 6 shows a cross section in which the electronic device 1 is cut so as to include the pins 16A and 16B as in the first embodiment.

  Unlike the first embodiment, the electronic device 1 according to the present embodiment has a cross-sectional structure in which the battery 13 and the first substrate 12A do not overlap in the thickness direction (z-axis direction) of the electronic device 1. Unlike the first embodiment, the processor 22 is mounted on the second substrate 12B, and is electrically connected to the pins 16B and 16D by the RF signal lines provided on the second substrate 12B. As shown in FIG. 6, the first board 12 </ b> A, the second board 12 </ b> B, and the battery 13 are arranged in parallel in the main surface direction (y-axis direction) of the electronic device 1. The thickness t2 of the electronic device 1 according to the present embodiment is smaller than the thickness t1 of the electronic device 1 according to the first embodiment because there is no overlap in the z-axis direction between the battery 13 and the first substrate 12A.

  Also in the electronic apparatus 1 according to the present embodiment, the wiring to the resin casing 11 is integrally formed by, for example, LDS. Therefore, the electronic device 1 according to the present embodiment does not require a space for passing the coaxial cable and an additional member, and contributes to downsizing similarly to the first embodiment.

  Moreover, the electronic device 1 according to the present embodiment can be configured to include two grounding members (pins 17C to 17D and 18C to 18D) that are disposed with the connection member (pins 16C to 16D) interposed therebetween. At this time, the electronic device 1 according to the present embodiment can ensure a stable pass characteristic of the RF signal as in the first embodiment.

(Other embodiments)
Although the present invention has been described based on the drawings and embodiments, it should be noted that those skilled in the art can easily make various variations and modifications based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, each component can be rearranged so as not to be logically contradictory, and a plurality of components can be combined into one or divided.

  For example, the electronic device 1 according to the embodiment includes two ground members (pins 17C to 17D and 18C to 18D) that are arranged with the connection member (pins 16C to 16D) interposed therebetween. Here, two grounding members are not necessarily provided for one connection member. For example, referring to FIG. 4, it is possible to provide one grounding member for one connecting member by limiting the frequency band to a range where passage loss does not occur much.

  For example, in the electronic apparatus 1 according to the second embodiment, the first substrate 12A, the second substrate 12B, and the battery 13 are one of these surfaces (the surface on the lower side in FIG. 6 and facing the display 14). Are arranged in parallel in the main surface direction so that the surfaces to be aligned are aligned. However, the first substrate 12A that does not substantially overlap in the thickness direction (z-axis direction) of the first antenna 21A and the electronic device 1 can be closer to the first antenna 21A than the position shown in FIG. . That is, the electronic device 1 can have a configuration in which at least one of the first substrate 12A and the second substrate 12B is arranged in parallel with the battery 13 in the main surface direction.

1 Electronic device 10 Rear cover 11, 11A, 11B, 11C Resin housing 12A First substrate 12B Second substrate 12C Substrate 13 Battery 14 Display 15 Front cover 16, 16A, 16B, 16C, 16D Pin 17C, 17D Pin 18C, 18D Pin 21A First antenna 21B Second antenna 22 Processor 23 RF signal line

Claims (6)

A first substrate, a second substrate, and a resin housing;
An electronic apparatus, wherein a wiring including a signal line for electrically connecting the first substrate and the second substrate is formed in the resin casing.   The electronic device according to claim 1, wherein the wiring formed in the resin casing includes a ground. A connection member connecting at least one of the first substrate and the second substrate and the signal line;
The electronic device according to claim 2, further comprising: a grounding member that connects at least one of the first substrate and the second substrate and the ground.   The electronic device according to claim 3, wherein the number of the grounding members is two, and the grounding members are arranged with the connection member interposed therebetween. With an antenna,
5. The electronic device according to claim 1, wherein the antenna overlaps at least one of the first substrate and the second substrate in a thickness direction of the electronic device. Equipped with a battery
6. The electronic device according to claim 1, wherein the first substrate, the second substrate, and the battery are arranged in parallel in a main surface direction of the electronic device.

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