JP2003150276A - Electronic device mounted equipment and its noise radiation suppressing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device mounted equipment whose reliability is improved by satisfying noise radiation specification value. SOLUTION: When the basic wave frequency of a clock signal or the 1/2 wavelength of the higher harmonic frequency is made coincident to the length of a keyboard plate, resonance with the coincident frequency is generated, and a radiation noise is increased. This increase quantity is suppressed so as not to be more than the radiation noise specification value specified by information processing equipment by mounting a radio absorber 2 between electronic device 6 and a keyboard plate 7, so that resonance due to the length made coincident to the 1/2 wavelength of the keyboard plate 7 can be prevented from being generated. Therefore, any radiation noise can be prevented from being generated in the basic wave of the clock signal or the higher harmonic signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device equipped with an electronic device and a method for suppressing noise emission thereof, and more particularly to an electronic device which operates by a clock signal and an information input function of the electronic device provided in the electronic device. The present invention relates to an electronic device-equipped device including a keyboard plate on which a keyboard is arranged, in which suppression of noise emission due to a clock signal conducted and radiated from the electronic device to the keyboard plate is improved, and a noise emission suppression method thereof.

[0002]

2. Description of the Related Art Electronic devices used in information processing equipment such as personal digital assistants and personal computers and having a clock signal circuit have a higher clock signal frequency in order to realize high-speed processing capability. Further, an electronic device-equipped device equipped with this electronic device can be equipped with or incorporates a circuit having a communication function in order to communicate with another device. The circuit having the communication function may have a wireless communication function in order to improve the portability of the electronic device-equipped device.

Electronic device-equipped equipment in which the electronic device having the clock signal circuit is mounted will be described below. Referring to FIG. 16 showing a front view of a conventional electronic device-equipped device equipped with a communication card having a wireless communication function, the electronic device-equipped device includes an electronic device-equipped device body 51 and a display unit 52. . A keyboard 53 is mounted on the main body 51, and a communication card 54 is mounted.
The communication card 54 has an antenna 55 for performing wireless communication.

Further, referring to FIG. 17 which is a sectional view of the electronic device-mounted apparatus shown in FIG. 16 taken along the section line AA ′, an electronic device including a printed circuit board is provided in a main body 51 of the electronic device-mounted device. A device 56 is arranged, and a communication card 54 having an antenna 55 is mounted in the main body 51.

A keyboard 53 is mounted on the upper part of the main body 51, and a keyboard plate 57 for supporting the keyboard 53 is mounted on the lower part of the keyboard 53 in order to maintain the strength of the keyboard 53.

On the other hand, Japanese Utility Model Laid-Open No. 04-025298 discloses a structure of an electronic device in which a radio wave absorber is provided on the inner surface of a case enclosing an electronic circuit.

[0007]

The structure of the conventional electronic device shown in FIG. 17 described above has the following problems. That is, in an electronic device that operates in synchronization with a predetermined clock signal, the clock signal includes a signal component having a harmonic frequency of an integral multiple, in addition to the fundamental wave frequency signal.

The clock signal containing the above-mentioned harmonic component is transmitted to the keyboard plate 5 inside the electronic device 56.
7 is conducted by electrostatic coupling and is radiated as noise from the keyboard plate 57. Depending on the amount of radiation noise, the radiation noise standard value defined by the information processing device may not be satisfied.

The reason for this is that when a clock signal containing a harmonic component is radiated at a radiation noise level depending on the shape of the keyboard plate 57, the fundamental frequency of the clock signal or a half wavelength of the harmonic frequency thereof. This is because when the length of the keyboard plate 57 matches, the resonance noise increases due to resonance at the matched frequency.

This can be explained by the current and voltage waveforms due to the resonance of the keyboard plate 57 shown in FIG.

That is, referring to FIG. 19 showing the shape of the keyboard plate 57, the keyboard plate 57 is shown.
Has a dimension L and a dimension W.

For example, the dimension L of the keyboard plate 57
Assuming that the length is 15 cm, when a 1 GHz signal whose length is 15 cm is ½ wavelength is transmitted to the keyboard plate 57, both ends of the keyboard plate 57 are in an open state, so that the maximum voltage is V at both ends. The maximum current I is obtained at the central length L / 2 of the keyboard plate 57. Under such conditions, the 1 GHz signal resonates at the length L of the keyboard plate 57.

Here, the keyboard plate 57 is 15c
In the case of m, since the resonance circuit is configured at 1 GHz, the keyboard plate 57 acts as a half-wave antenna and
This will cause an increase in radiated noise at GHz.

In addition, the above-mentioned actual Kaihei 04-025298
In the gazette, the structure in which the electromagnetic wave absorber is placed on the inner surface of the case enclosing the electronic circuit requires that the shield material be placed in all places when the case is connected to the outside or a keyboard is installed. However, if the keyboard plate resonates and noise at the resonance frequency is radiated due to the resonance, the noise cannot be suppressed and the radiation noise increases.

The present invention has been made in view of the above-mentioned conventional drawbacks, and in an electronic device which operates in synchronization with a clock signal, a clock signal containing a harmonic component is
A structure for suppressing further increase in noise amount due to resonance with a harmonic frequency of a clock signal when radiated at a radiated noise level depending on the shape of a keyboard plate, and a method for suppressing the noise radiation by the structure. The purpose of this is to provide an electronic device-equipped device that satisfies the noise emission standard value and has improved reliability.

[0016]

In an electronic device-equipped device of the present invention, a keyboard for giving a control instruction to an electronic device operating in synchronization with a clock is attached to a keyboard plate on the lower surface of the keyboard, and noise radiation attached to the lower surface of the keyboard. It is characterized by having a structure provided with a suppressing means together.

Another feature of the electronic device-equipped equipment of the present invention is that
An electronic device that operates in synchronization with a clock signal, a keyboard mounting keyboard plate that is arranged so as to face the electronic device, and noise emission suppressing means that is mounted on the keyboard plate surface so as to face the electronic device. And at least.

Another feature of the electronic device-equipped device of the present invention is an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, a keyboard plate that supports the keyboard, and Noise radiation suppressing means for suppressing the noise resonating at the harmonic frequency of the clock signal from being radiated from the keyboard plate, wherein the noise radiation suppressing means is provided on the side opposite to the keyboard arranging surface of the keyboard plate. It has a structure mounted on the plate surface.

Still another feature of the electronic device-equipped device of the present invention comprises an electronic device which operates in synchronization with a clock signal, a keyboard which gives a control instruction to the electronic device, and a keyboard plate which supports the keyboard. In the electronic device-equipped equipment, noise radiation suppressing means for suppressing the noise resonating at the harmonic frequency of the clock signal from being radiated from the keyboard plate is provided, and the noise radiation suppressing means is in non-contact with the electronic device. It is characterized in that it is provided with a structure to be mounted within a predetermined range of the keyboard plate surface which is arranged in a state and facing each other.

Still another feature of the electronic device-equipped device of the present invention is to provide an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and a keyboard plate that supports the keyboard. In a device equipped with an electronic device, a radio wave absorber for suppressing resonance due to a harmonic frequency of the clock signal is mounted between the electronic device and the keyboard plate, and the radio wave absorber is the keyboard plate. It has a structure that covers more than 1/3 of the mounting surface.

Another feature of the electronic device-equipped equipment of the present invention is that
In an electronic device-equipped device including an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and a keyboard plate that supports the keyboard, the harmonic frequency of the clock signal is 70.
When the frequency is 0 MHz or more, a radio wave absorber for suppressing resonance due to the harmonic frequency of the clock signal is mounted between the electronic device and the keyboard plate, and the radio wave absorber has a length of 0.1 mm or more. It has a structure having a thickness.

Still another feature of the electronic device-equipped device of the present invention is to include an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and a keyboard plate that supports the keyboard. In the electronic device-equipped device, a radio wave absorber for suppressing resonance due to the harmonic frequency of the clock signal is provided between the electronic device and the keyboard plate when the harmonic frequency of the clock signal is 700 MHz or more. Installed,
In addition, the electromagnetic wave absorber covers 1/3 or more of the mounting surface of the keyboard plate, and the thickness of the electromagnetic wave absorber is 0.1 mm or more.

The radio wave absorber is mounted on the central portion of the mounting surface of the keyboard plate.

Further, each of the plurality of electronic devices may have one radio wave absorber.

Furthermore, the radio wave absorber may have a rectangular flat plate shape, and the width, length and / or thickness of the radio wave absorber may be determined according to an increase in noise due to resonance. it can.

Further, it has a structure in which a circuit having a wireless communication function can be mounted.

Further, it may have a structure in which a circuit having a wireless communication function is incorporated.

Furthermore, it may have a structure in which a plate having no keyboard is provided.

A noise radiation suppressing method for an electronic device-equipped device according to the present invention comprises: an electronic device which operates in synchronization with a clock signal; a keyboard for giving a control instruction to the electronic device; a keyboard plate for supporting the keyboard; In the facing surface of the keyboard plate facing the electronic device and arranged in a non-contact state, with a noise radiation suppressing means mounted within a predetermined range,
The noise radiation suppressing means is used to attenuate noise resonating at a harmonic frequency of the clock signal to suppress noise radiation from the keyboard plate.

Another feature of the noise emission suppressing method for electronic device-equipped equipment of the present invention is an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to this electronic device, and a keyboard that supports the keyboard. A plate, and between the electronic device and the keyboard plate, 1/3 of a mounting surface of the keyboard plate.
It is to suppress the resonance due to the harmonic frequency of the clock signal by using the radio wave absorber mounted so as to cover the above.

Still another feature of the noise emission suppressing method for electronic device-equipped equipment of the present invention is that an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and the keyboard is supported. A keyboard plate and having a thickness of 0.1 mm mounted between the electronic device and the keyboard plate when the harmonic frequency of the clock signal is 700 MHz or more.
The above-mentioned radio wave absorber is used to suppress the resonance due to the harmonic frequency of the clock signal.

Still another feature of the noise emission suppressing method for electronic device-equipped equipment of the present invention is that an electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to this electronic device, and the keyboard is supported. A keyboard plate, which is mounted between the electronic device and the keyboard plate and covers 1/3 or more of the mounting surface of the keyboard plate when the harmonic frequency of the clock signal is 700 MHz or more. At the same time, a radio wave absorber having a thickness of 0.1 mm or more is used to suppress resonance due to the harmonic frequency of the clock signal.

Further, according to the increase of noise due to resonance,
Resonance due to the harmonic frequency of the clock signal can be suppressed by using the radio wave absorber having a rectangular flat plate shape and having a determined width, length and / or thickness.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a first electronic device-equipped device of the present invention.
3 is a cross-sectional view of the embodiment of FIG. Referring to FIG. 1, in the first embodiment, an electronic device 6 including a printed circuit board is provided in a main body 1. A communication card 4 having an antenna 5 is mounted in the main body 1. A keyboard 3 is arranged above the main body 1, and a keyboard plate 7 for supporting a keyboard is arranged below the keyboard 3 in order to maintain the strength of the keyboard 3. The radio wave absorber 2 is disposed on the electronic device 6 side of the keyboard plate 7.

Next, the operation of the first embodiment of the present invention having the above configuration will be described.

A clock signal is used to operate the electronic device 6. This clock signal includes a signal component having a harmonic frequency that is an integral multiple, in addition to the fundamental wave frequency signal.

In FIG. 1, a clock signal used inside the electronic device 6 and containing a harmonic component is conducted by electrostatic coupling to the keyboard plate 7 and radiated as noise from the keyboard plate 7.

When a clock signal including a harmonic component, for example, a clock signal having a fundamental frequency of 100 MHz and a signal component having a harmonic frequency of 1 GHz that is 10 times higher, 1 GHz
1/2 wavelength is 15 cm.

When the dimension L, which is the shape of the keyboard plate 7, is 15 cm, since the electromagnetic wave absorber 2 is arranged between the electronic device 6 and the keyboard plate 7,
Resonance does not occur due to the size corresponding to the half wavelength of the keyboard plate 7.

Therefore, the harmonic signal of the clock signal 1GH
Radiated noise does not increase at z.

Next, the increase in resonance and radiation noise due to the ½ wavelength of the keyboard plate 7 will be described.

Under the resonance condition of FIG. 18, the 1 GHz signal is radiated as noise from the keyboard plate 7.

Referring to FIG. 2 showing the radiation noise increase characteristic due to resonance, this figure shows a graph of the radiation noise amount measured from the keyboard plate having the resonance characteristic around 1 GHz.

Measuring frequency is from 700 MHz to 2.7 GH
The graph shows the characteristics when the range of z is set, the noise radiation amount when there is no keyboard plate is 0 dB, and when there is a keyboard plate.

It can be seen that the presence of the keyboard plate increases the radiated noise by 24 dB near 1 GHz.

Next, graphs of the characteristics when the electromagnetic wave absorber is arranged on the keyboard plate are shown in FIGS. Referring to FIG. 3, the noise increase amount is reduced by 12 dB in the vicinity of 1 GHz due to the absorption effect of the radio wave absorber 2 having a thickness of 0.25 mm.

Further, referring to FIG. 4, the noise increase amount is 1 G due to the absorption effect of the radio wave absorber having a thickness of 0.5 mm.
It is reduced by 17 dB near Hz.

Further, referring to FIG. 5, the noise increase amount is 1 GH due to the absorption effect of the radio wave absorber having a thickness of 1 mm.
It is reduced by 20 dB near z.

Referring to FIG. 6, the noise increase amount is reduced by 23 dB in the vicinity of 1 GHz due to the absorption effect of the radio wave absorber having a thickness of 2.5 mm.

Referring to FIG. 7 showing the radiation noise increase characteristic due to resonance, this figure is a graph showing the radiation noise amount measured from the keyboard plate having the resonance characteristic around 2 GHz.

That is, the graph shows the characteristics when the measurement frequency is in the range of 700 MHz to 2.7 GHz, the noise radiation amount when the keyboard plate 7 is not present is 0 dB, and the keyboard plate 7 is present.

It can be seen that the presence of the keyboard plate 7 increases the radiation noise by 29 dB near 2 GHz.

Next, graphs of characteristics in which the radio wave absorber 2 is arranged on the keyboard plate 7 are shown in FIGS. Referring to FIG. 8, due to the absorption effect of the electromagnetic wave absorber having a thickness of 0.25 mm, the noise increase amount is 1 at around 2 GHz.
It is reduced by 2 dB.

Further, referring to FIG. 9, the noise increase amount is 2 G due to the absorption effect of the radio wave absorber having a thickness of 0.5 mm.
It is reduced by 17.5 dB near Hz.

Further, referring to FIG. 10, the noise increase amount is 2 G due to the absorption effect of the radio wave absorber having a thickness of 1 mm.
It is reduced by 22 dB in the vicinity of Hz.

Furthermore, referring to FIG. 11, 2.5
Due to the absorption effect of the mm-thick radio wave absorber, the noise increase amount is reduced by 27 dB in the vicinity of 2 GHz.

On the other hand, referring to FIG. 12 showing the noise reduction characteristics with respect to the thickness change of the electromagnetic wave absorber, this figure shows 1G.
The effect amounts at two frequencies of Hz and 2 GHz are shown. The effect amount at 1 GHz is from 0 dB without a radio wave absorber to 12 dB and 0.5 m at a thickness of 0.25 mm.
17 dB at m thickness, 20 dB at 2.5 mm thickness, 2.5
It can be seen that there is a noise reduction effect of 23 dB when the thickness is mm.

This makes it possible to provide a radio wave absorber having a thickness corresponding to the amount of increase in radiation noise due to the keyboard plate.

Next, a second embodiment of the electronic device mounting apparatus of the present invention will be described. Referring to FIG. 13 showing a cross-sectional view of the electronic device-equipped equipment of the second embodiment, the above-mentioned first
1 is different from the structure of the embodiment in that the electromagnetic wave absorber is mounted on the entire surface of the keyboard plate in FIG. 1, whereas the electromagnetic wave absorber is mounted not on the entire surface of the keyboard plate but in the center of the keyboard plate. Is.

In FIG. 13, the electronic device-equipped equipment has an electronic device 6 including a printed circuit board in the main body 1. A communication card 4 having an antenna 5 is mounted in the main body 1. A keyboard 3 is arranged above the main body 1, and a keyboard plate 7 is arranged below the keyboard 3 in order to maintain the strength of the keyboard 3. On the electronic device 6 side of the keyboard plate 7, a radio wave absorber 8 is attached in the center.

A clock signal used as a synchronizing signal inside the electronic device 6 and containing a harmonic component is conducted by electrostatic coupling to the keyboard plate 7 and radiated as noise from the keyboard plate 7.

When a clock signal including a harmonic component, for example, a clock signal having a fundamental frequency of 100 MHz and a signal component having a harmonic frequency of 1 GHz that is 10 times higher, 1 GHz
1/2 wavelength is 15 cm.

When the dimension L is 15 cm in the shape of the keyboard plate 7, since the electromagnetic wave absorber 8 is installed in the center of the keyboard plate 7 between the electronic device 6 and the keyboard plate 7, The resonance due to the size corresponding to the / 2 wavelength does not occur because the maximum current in the center of the keyboard 7 is absorbed by the radio wave absorber 8.

Therefore, the harmonic signal of the clock signal is 1 GHz.
Radiated noise does not increase at z.

Next, a third embodiment of the electronic device-mounted equipment of the present invention will be described. Referring to FIG. 14, which is a sectional view of an electronic device-equipped device according to the third embodiment, the difference from the first embodiment described above is that one electronic device is shown in FIG. It is an electronic device.

That is, in FIG. 14, an electronic device 6 and an electronic device 9 each composed of a printed circuit board are provided in the main body 1 of the electronic device mounting apparatus. A communication card 4 having an antenna 5 is also mounted in the main body 1.
A keyboard 3 is arranged above the main body 1, and a keyboard plate 7 is arranged below the keyboard 3 in order to maintain the strength of the keyboard 3. Further, the radio wave absorber 2 is disposed on the electronic device 6 and electronic device 9 sides of the keyboard plate 7.

In the above-mentioned structure, the clock signal used as a synchronizing signal in the electronic device 6 or the electronic device 9 and containing a harmonic component is conducted by electrostatic coupling to the keyboard plate 7 and is transmitted as noise from the keyboard plate 7. Is emitted.

When a clock signal including a harmonic component, for example, a clock signal having a fundamental frequency of 100 MHz and a signal component having a harmonic frequency of 1 GHz that is 10 times higher, 1 GHz
1/2 wavelength is 15 cm.

Dimension L which is the shape of the keyboard plate 7.
When the distance is 15 cm, the electromagnetic wave absorber 2 is installed between the electronic device 6 and the keyboard plate 7, so that resonance due to the size corresponding to the half wavelength of the keyboard plate 7 is generated by the electromagnetic wave absorber 2. do not do. Therefore, the radiation noise does not increase at the harmonic signal of 1 GHz of the clock signal.

Next, a fourth embodiment of the electronic device-mounted equipment of the present invention will be described. Referring to FIG. 15 showing a cross-sectional view of an electronic device-equipped device according to a fourth embodiment, the difference from the above-described first embodiment is that a keyboard and a keyboard plate are arranged in FIG. The electromagnetic wave absorber is attached to the plate without the keyboard, while the absorber is attached.

In FIG. 15, an electronic device 6 composed of a printed circuit board is installed in the main body 1 of the electronic device mounting equipment. A communication card 4 having an antenna 5 is also mounted in the main body 1. Further, a plate 10 is disposed on the upper part of the main body 1, and the electronic device 6 of the plate 10 is provided.
The radio wave absorber 2 is arranged in the center on the side.

In the above-mentioned structure, the clock signal used as a synchronizing signal inside the electronic device 6 and containing a harmonic component is conducted by electrostatic coupling to the plate 10 and radiated as noise from the plate 10.

When a clock signal containing a harmonic component, for example, a clock signal having a fundamental frequency of 100 MHz and a signal component having a harmonic frequency of 1 GHz, which is 10 times higher, is 1 GHz.
1/2 wavelength is 15 cm.

The dimension L which is the shape of the plate 10 is 15c.
In the case of m, since the electromagnetic wave absorber 2 is installed on the plate 10 between the electronic device 6 and the plate 10, the electromagnetic wave absorber 2 absorbs the resonance due to the size matching the half wavelength of the plate 10. And does not occur. Therefore, the radiation noise does not increase at the harmonic signal of 1 GHz of the clock signal.

[0076]

As described above, according to the present invention, by disposing the electromagnetic wave absorber between the electronic device and the keyboard plate, the electronic device which operates in synchronization with the clock signal is electrostatically coupled to the keyboard plate. The clock signal containing the higher harmonic component conducted by means of the electromagnetic wave absorber does not emit noise from the keyboard due to the resonance suppression of the keyboard plate. Therefore, the radiation noise standard value defined by the information processing device can be satisfied, which contributes to the improvement of the reliability of the electronic device-equipped device.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a first embodiment of an electronic device-equipped device of the present invention.

FIG. 2 is a diagram showing a radiation noise increase characteristic due to resonance.

FIG. 3 is a graph of characteristics when a radio wave absorber having a thickness of 0.25 mm is arranged on a keyboard plate.

FIG. 4 is a graph of characteristics when a 0.5 mm-thick electromagnetic wave absorber is arranged on a keyboard plate.

FIG. 5 is a graph of characteristics when a 1 mm-thick electromagnetic wave absorber is arranged on a keyboard plate.

FIG. 6 is a graph of characteristics when a 2.5 mm-thick electromagnetic wave absorber is arranged on a keyboard plate.

FIG. 7 is a diagram showing a radiation noise increase characteristic due to resonance.

FIG. 8 is a graph of characteristics in which the electromagnetic wave absorber 2 having a thickness of 0.25 mm is arranged on the keyboard plate 7.

FIG. 9 is a graph of characteristics in which the electromagnetic wave absorber 2 having a thickness of 0.5 mm is arranged on the keyboard plate 7.

FIG. 10 is a graph of characteristics in which the 1 mm-thick electromagnetic wave absorber 2 is arranged on the keyboard plate 7.

FIG. 11 is a graph of characteristics in which the radio wave absorber 2 having a thickness of 2.5 mm is arranged on the keyboard plate 7.

FIG. 12 is a diagram showing noise reduction characteristics with respect to changes in the thickness of the radio wave absorber.

FIG. 13 is a cross-sectional view of an electronic device mounting apparatus according to a second embodiment.

FIG. 14 is a sectional view of an electronic device-mounted apparatus according to a third embodiment.

FIG. 15 is a cross-sectional view of a device equipped with an electronic device according to a fourth embodiment.

FIG. 16 is a front view showing an example of a conventional electronic device-equipped device.

FIG. 17 is a section line A of the electronic device-equipped device shown in FIG.
It is sectional drawing by -A '.

FIG. 18 is a current caused by resonance of the keyboard plate 57,
It is a voltage waveform diagram.

FIG. 19 is a view showing the shape of a keyboard plate 57.

[Explanation of symbols]

1,51 body 2,8 Radio wave absorber 3,53 keyboard 4,54 communication card 5,55 antenna 6, 9, 56 Electronic device 7,57 keyboard plate 10 plates 52 display

Claims (18)

[Claims] 1. A keyboard for giving a control instruction to an electronic device operating in synchronization with a clock has a structure including a keyboard plate mounted on the lower surface of the keyboard and a noise emission suppressing means mounted on the lower surface of the keyboard. A device equipped with an electronic device. 2. An electronic device that operates in synchronization with a clock signal, a keyboard mounting keyboard plate that is arranged so as to face the electronic device, and a keyboard plate surface that is mounted so as to face the electronic device. A device equipped with an electronic device, comprising: 3. An electronic device that operates in synchronization with a clock signal, and a keyboard that gives control instructions to the electronic device.
A keyboard plate that supports the keyboard, and a noise radiation suppressing unit that suppresses noise that resonates at a harmonic frequency of the clock signal from being emitted from the keyboard plate, and the noise radiation suppressing unit is the keyboard plate. 2. An electronic device-equipped device having a structure mounted on a plate surface on the side opposite to the keyboard arrangement surface. 4. An electronic device that operates in synchronization with a clock signal, and a keyboard that gives control instructions to the electronic device.
In an electronic device-equipped device that includes a keyboard plate that supports the keyboard, a noise radiation suppressing unit that suppresses noise resonating at a harmonic frequency of the clock signal from being radiated from the keyboard plate,
The electronic device mounting apparatus, wherein the noise radiation suppressing means has a structure that is mounted within a predetermined range of the keyboard plate surface arranged in a non-contact state and facing the electronic device. . 5. An electronic device that operates in synchronization with a clock signal, and a keyboard that gives control instructions to the electronic device.
In an electronic device-equipped device including a keyboard plate supporting the keyboard, a radio wave absorber for suppressing resonance due to a higher harmonic frequency of the clock signal is mounted between the electronic device and the keyboard plate, and This electronic wave absorber has a structure that covers one third or more of the mounting surface of the keyboard plate. 6. An electronic device that operates in synchronization with a clock signal, and a keyboard that gives control instructions to the electronic device.
In a device equipped with an electronic device including a keyboard plate that supports the keyboard, when the harmonic frequency of the clock signal is 700 MHz or more, a harmonic frequency of the clock signal is generated between the electronic device and the keyboard plate. An electronic device-equipped device having a structure in which a radio wave absorber for suppressing resonance is mounted, and the radio wave absorber has a thickness of 0.1 mm or more. 7. An electronic device that operates in synchronization with a clock signal, and a keyboard that gives control instructions to the electronic device.
In a device equipped with an electronic device including a keyboard plate that supports the keyboard, when the harmonic frequency of the clock signal is 700 MHz or more, a harmonic frequency of the clock signal is generated between the electronic device and the keyboard plate. A structure in which a radio wave absorber for suppressing resonance is attached, the radio wave absorber covers 1/3 or more of the mounting surface of the keyboard plate, and the radio wave absorber has a thickness of 0.1 mm or more. An electronic device-equipped device comprising: 8. The electronic device-equipped device according to claim 5, having a structure in which the radio wave absorber is mounted on a central portion of a mounting surface of the keyboard plate. 9. The electronic device-equipped device according to claim 5, wherein each of the plurality of electronic devices has one of the radio wave absorbers. 10. The electromagnetic wave absorber has a rectangular flat plate shape,
8. The electronic device-equipped device according to claim 5, 6 or 7, further comprising a structure in which the width, length and / or thickness of the radio wave absorber is determined according to an increase in noise due to resonance. 11. The electronic device-equipped device according to claim 1, which has a structure capable of mounting a circuit having a wireless communication function. 12. The electronic device-equipped device according to claim 1, which has a structure having a built-in circuit having a wireless communication function. 13. The electronic device-equipped device according to claim 1, which has a structure in which a plate having no keyboard is provided. 14. An electronic device that operates in synchronization with a clock signal, a keyboard that gives control instructions to the electronic device, and a keyboard plate that supports the keyboard.
The noise radiation suppressing means is provided on the facing surface of the keyboard plate facing the electronic device in a non-contact state, the noise radiation suppressing means being mounted within a predetermined range, and using the noise radiation suppressing means. A method for suppressing noise radiation in an electronic device-equipped device, comprising: attenuating noise that resonates at a harmonic frequency of the clock signal to suppress noise radiation from the keyboard plate. 15. An electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and a keyboard plate that supports the keyboard, and between the electronic device and the keyboard plate. A method for suppressing noise radiation in an electronic device-equipped device, which suppresses resonance due to a harmonic frequency of the clock signal, using a radio wave absorber that covers at least 1/3 of a mounting surface of the keyboard plate. 16. An electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and a keyboard plate that supports the keyboard, and a harmonic frequency of the clock signal is 7
When the frequency is 00 MHz or more, a radio wave absorber having a thickness of 0.1 mm or more mounted between the electronic device and the keyboard plate is used to suppress resonance due to a harmonic frequency of the clock signal. Noise suppression method for electronic device-equipped equipment. 17. An electronic device that operates in synchronization with a clock signal, a keyboard that gives a control instruction to the electronic device, and a keyboard plate that supports the keyboard, the harmonic frequency of the clock signal being 7
A radio wave absorber mounted between the electronic device and the keyboard plate, covering 1/3 or more of the mounting surface of the keyboard plate and having a thickness of 0.1 mm or more when the frequency is 00 MHz or more. A method for suppressing noise radiation in an electronic device-equipped device, wherein resonance due to a harmonic frequency of the clock signal is suppressed. 18. A resonance according to a harmonic frequency of the clock signal using the radio wave absorber having a rectangular flat plate shape and having a width, a length and / or a thickness determined according to an increase in noise due to the resonance. 15. The method for suppressing noise radiation of electronic device-equipped equipment according to claim 12, 13 or 14.