JP2012191654A - High-frequency module and receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-frequency module and a receiver capable of discharging electric field and magnetic field to the outside of a shield part, allowing electronic components to be arranged more close to each other in the shield part, and achieving downsizing.SOLUTION: A high-frequency module comprises: integrated circuits IC 112 and 113 each incorporating an oscillator including an inductor; and a shield case 114 as a shield part in a shape for covering the ICs 112 and 113. In the shield case 114 as the shield part, openings 116A and 116B which are one half or more profile size of the ICs 112 and 113 are formed in regions facing the positions where the ICs 112 and 113 are arranged.

Description

  The present invention relates to a high-frequency module and a receiving apparatus that can be applied to a television tuner or the like.

In recent years, a television (TV) tuner, which is an example of a high-frequency module, is built not only in a TV receiver but also in an IT device such as a personal computer (PC).
The receiver is configured as a so-called double tuner receiver equipped with a terrestrial tuner and a satellite tuner in order to be able to receive terrestrial television broadcasts and satellite wave television broadcasts.

  FIG. 1 is a block diagram illustrating a configuration example of a general broadcast wave receiving apparatus of a double tuner applied to an IT device.

  1 includes a satellite tuner 2, a terrestrial tuner 3, an input terminal 4, a splitter 5, a PCI-Express bridge 6, a power source 7, a memory 8, and a card edge connector unit 9.

FIG. 1 is an example of an application in a PC using a computer interface called PCI-Express.
In the circuit of this configuration, the height is standardized so that the circuit is built in a predetermined slot, and it is necessary to make the height within 3.75 mm.

In the receiving apparatus 1, the high-frequency signal input from the input terminal 4 is distributed via the splitter 5, then supplied to the two tuners 2 and 3, and demodulated to output data.
The data is output to the digital data PCI-Express interface via the PCI-Express bridge 6.
At that time, the power supply 7 supplies necessary voltages and currents, and the memory 8 performs an operation of holding necessary storage data.

  By the way, a receiver of a double tuner is required to be downsized and simplified in mounting design. In order to cope with this, a receiving apparatus in which two tuners are arranged in one double tuner module has been put to practical use.

FIG. 2 is a block diagram illustrating a configuration example of a broadcast wave receiving apparatus to which a double tuner module is applied.
In FIG. 2, the receiving apparatus 1 </ b> A has a double tuner module 10.
In addition, the function part which attached | subjected the same number as FIG. 1 performs the same operation | movement similarly to FIG.

  FIG. 3 is a diagram showing a simplified configuration of a double tuner module arranged on a PCI-Express board.

In the example, the double tuner module 10 is designed with a 2.3 mm height as a thinner height on the substrate 11.
As described above, when a thin module is configured, the satellite tuner 12 and the terrestrial tuner 13 are implemented as an integrated circuit (IC) mounted on the substrate 11 and covered with the shield case 14.
Thus, in order to realize a thin tuner, a more integrated IC is preferable in the semiconductor to be used. Similarly, the satellite tuner 12 and the terrestrial tuner 13 in FIG. Incorporates a local oscillator and an inductor used therefor.

  FIG. 4 is a diagram for explaining an example of an inductor built in an IC.

In a semiconductor operating in a high frequency band, a voltage controlled oscillator (VCO: Voltage Controlled Oscillator) generally realized by an external circuit is an on-chip type VCO 21 laid out on the IC chip 20 of FIG. The inductor 22 essential for the VCO 21 is realized by a spiral shape having a concentric shape by aluminum wiring.
This example is an explanatory diagram of a process called QUBIC4 of NXP, and is an example of an IC in which an inductor used for a local oscillator (VCO 21 in the figure) is configured with an IC pattern layout.

In general, since an inductor built in an IC is arranged on a plane, it has a spiral structure in which concentric circles are spirally wound as shown in FIG.
For this reason, an electric field and a magnetic field induced from the inductor are radiated in the vertical direction on the plane of the paper during the operation of the IC.
Therefore, when using a plurality of ICs with a built-in local oscillation circuit and a built-in inductor, it is necessary to consider the influence of the electric field generated around the IC.

  FIGS. 5A and 5B are diagrams showing the concept of an electric field radiated by an IC incorporating an inductor.

FIG. 5A shows an example in which a radio wave 31 is radiated from the IC 30 mounted on the circuit board 11.
In this case, the arc-shaped electric field intensity is in the vicinity of the IC 30, but becomes parallel to the radiation surface as the distance from the IC 30 that is the radiation element increases.

FIG. 5B shows a state where it is mounted on an actual tuner module.
That is, the copper foil surface 33 is covered with the shield case 14 in the lateral direction and the top surface direction on the bottom surface of the IC 30 mounted on the circuit board 11. In this case, since the emitted radio wave 31 is reflected by the shield case 14 and the copper foil surface 33 in the vicinity, the arc-shaped electric field is propagated through the path 32 while being reflected.

  The shield case 14 is made of a thin material and is commonly known as an alloy of copper, nickel and zinc, which is excellent in solderability. In the case where the restrictions are loose, an inexpensive tin plate or a similar product may be used.

6A and 6B are diagrams showing the concept of a magnetic field radiated by an IC incorporating an inductor.
6A and 6B, the same components as those in FIG. 5 are denoted by the same reference numerals.

In FIG. 6A, a loop is formed in which the magnetic field 40 is induced upward from the IC 30 and returns to the bottom surface side.
Similarly, as shown in FIG. 6B, the magnetic field that hits the conductor surface of the copper foil surface 33 on the surface of the shield case 14 and the circuit board 11 generates an eddy current 41. This eddy current propagates in the conductor and is diffused in the conductor.

  FIGS. 7A and 7B are diagrams equivalently showing the propagation of a high-frequency signal by the electric and magnetic fields of FIGS.

In FIG. 7A, when the shield case 14 is in the vicinity of the upper surface of the IC 30, the stray capacitance 50 replaces that an electric field and a magnetic field are transmitted through the shield case by reflection or induction of current.
FIG. 7B is an explanatory diagram applied to the double tuner module of FIG. 3 and shows a state in which the satellite tuner 12 and the terrestrial tuner 13 are connected via the stray capacitance 50.

  It can be easily understood that the inductor built in the IC 30 is an element that generates an electromagnetic field when a current is passed, and conversely an element that induces a current when placed in an electromagnetic field.

JP 2007-103610 A

  By the way, as described above, it is necessary to consider the evolution of the operating frequency of the IC as a factor that facilitates the emission of high-frequency signals.

As shown in FIG. 4, in an IC with a built-in VCO, an inductor suitable for circuit operation is generally used. However, since it is limited by the size of the IC, only a space of several millimeters square is usually provided. is there.
In this case, the inductance value that can be realized is only about 10 nH.
Under this condition, for example, if you configure a parallel resonator and calculate the resonance frequency,
f = 1 / 2π√LC, C = 1 / (2πf) ² L
It becomes. For example, if f = 200 MHz, C = 63 pF is required.

  However, 63 pF is very large as the capacitance created inside the IC, and securing the area of the opposing electrode surfaces constituting the capacitor increases the chip size and increases the cost.

On the other hand, in semiconductor processes that are becoming faster and finer year by year, the operating frequency has entered the gigahertz band, and can operate in a region several times the frequency required for the satellite tuner and the terrestrial tuner.
As a result of the evolution of technology in a manner that balances the semiconductor internal components and the operating frequency of the process, a method of performing frequency conversion by dividing the frequency using a VCO that oscillates at a multiplied frequency of the reception frequency has become mainstream.

In the case of the satellite tuner 12, since the local frequency is around 2 to 4 GHz, the wavelength is about 70 to 140 mm.
At this time, if the double tuner is to be realized with one module, the interval between the tuner ICs easily fits within the size of λ / 4.
A distance of λ / 4 causes an efficient resonance for reception of radio waves, and causes a situation where radio waves are particularly likely to propagate.

  FIG. 8 is a diagram illustrating an example of interference between tuners in this way.

The example shown in FIG. 8 shows the VCO oscillation of one tuner as a local frequency.
Then, sidebands SB1 and SB2 due to electromagnetic spurious generated from another tuner are generated on both sides of the local frequency in the vicinity of the IF where the 1/2 local frequency and the RF signal are frequency-converted. For this reason, frequency conversion is performed on both sides of the IF in the same manner.

Thus, as a result of interference between tuners occurring at a high frequency in the gigahertz band, frequency conversion is performed together with the originally required RF signal and appears in the IF band.
This frequency conversion has a plurality of paths such as interference between VCO circuits or electromagnetic spurious superimposed on other circuits being frequency-converted together in a mixer unit that performs frequency conversion.

  As described above, when an IC with an RF circuit such as an oscillator such as a VCO is covered with a thin metal casing, the smaller the casing, the more electromagnetic waves propagate around it, generating spurious noise in the reception band. It becomes easy to let you.

Patent Document 1 describes an electronic device configured to deform a shield case so that noise generated on a circuit board is efficiently released to the shield case and reduces the influence on adjacent circuits. .
In this electronic device, the metal part of the shield case is subjected to a drawing process so as to be close to an IC having a frequency conversion circuit inside the tuner, and the shield case is used as a ground conductor that absorbs radio waves emitted from the IC. Used.
A slit for heat dissipation is formed in the aperture portion.
Although this electronic device has a function of absorbing electromagnetic waves and preventing leakage in the shield case, it is difficult to prevent interference between tuners due to the influence of electric and magnetic fields.

  The present invention can discharge an electric field and a magnetic field to the outside of a shield part, can arrange electronic parts in the shield part closer to each other, and can achieve downsizing, and thus can be downsized. Is to provide.

  A high-frequency module according to a first aspect of the present invention includes an integrated circuit incorporating an oscillator, and a shield portion shaped to cover the integrated circuit, and the shield portion is a region facing an arrangement position of the integrated circuit. In addition, an opening having a size of ½ or more of the shape size of the integrated circuit is formed.

  A receiving apparatus according to a second aspect of the present invention includes a satellite broadcast receiving circuit including an input terminal to which a satellite wave broadcast signal or a terrestrial broadcast signal is input, a satellite tuner having a frequency conversion function of the satellite wave broadcast signal, A terrestrial broadcast receiving circuit including a terrestrial tuner having a frequency conversion function of the terrestrial broadcast signal, a satellite wave broadcast signal input from the input terminal is distributed to the satellite broadcast receiving circuit, and the terrestrial broadcast signal is A demultiplexing circuit for demultiplexing to the terrestrial broadcast receiving circuit, and the satellite tuner and the terrestrial tuner are formed as a satellite tuner integrated circuit and a terrestrial tuner integrated circuit with a built-in oscillator. A satellite tuner integrated circuit and a shield portion shaped to cover the terrestrial tuner integrated circuit, the shield portion comprising the satellite tuner integrated circuit and Serial in a region facing the position of at least one integrated circuit of the terrestrial tuner integrated circuit, the opening of 1/2 or more the size of the feature size of the integrated circuit is formed.

  According to the present invention, the electric field and the magnetic field can be discharged to the outside of the shield part, the electronic components in the shield part can be arranged closer to each other, and the module can be downsized.

It is a block diagram which shows the structural example of the general broadcast wave receiver of a double tuner applied to IT apparatus etc. It is a block diagram which shows the structural example of the broadcast wave receiver which applied the double tuner module. It is a figure which shows the simple structure of the double tuner module arrange | positioned on a PCI-Express board | substrate. It is a figure for demonstrating an example of the inductor incorporated in IC. It is a figure which shows the concept of the electric field which IC which incorporates an inductor radiates | emits. It is a figure which shows the concept of the magnetic field which IC which incorporates an inductor radiates | emits. It is a figure which shows equivalently the propagation of the high frequency signal by the electric field of FIG. 5 and FIG. 6, and a magnetic field. It is a figure which shows an example in which the interference between tuners has arisen. It is a figure which shows the structural example of the broadcast signal receiver which employ | adopted the high frequency module which concerns on the 1st Embodiment of this invention. It is a figure which shows the simple structure of the principal part of the double tuner module employ | adopted as an example of the high frequency module which concerns on this 1st Embodiment. It is a figure which shows the specific structural example of the double tuner module employ | adopted as an example of the high frequency module which concerns on this embodiment. It is a figure for demonstrating the principle of the high frequency module which has an opening part concerning the 1st embodiment. It is a figure for demonstrating the specific structural example of the opening part formed in the shield case which concerns on the present embodiment. It is a figure for demonstrating the other specific structural example of the opening part formed in the shield case which concerns on this embodiment. It is a figure which shows the example which measured the interference with respect to a satellite tuner from a terrestrial tuner. It is a figure which shows the structural example of the double tuner module in the broadcast signal receiver which concerns on the 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The description will be given in the following order.
1. First Embodiment 2. FIG. Second embodiment

<1. First Embodiment>
FIG. 9 is a diagram illustrating a configuration example of a broadcast signal receiving apparatus employing the high frequency module according to the first embodiment of the present invention.
FIG. 10 is a diagram illustrating a simplified configuration of a main part of a double tuner module employed as an example of the high-frequency module according to the first embodiment.
FIG. 11 is a diagram illustrating a specific configuration example of a double tuner module employed as an example of the high-frequency module according to the present embodiment.

The receiving apparatus 100 includes a double tuner module 110, an input terminal 120, a PCI-Express bridge 130, a power source 140, a memory 150, and a card edge connector unit 160.
The receiving apparatus 100 in FIG. 9 is an example of an application in a PC using a computer interface called PCI-Express.

  In the present embodiment, a double tuner module 110 shown as an example of a high-frequency module is configured to be able to receive satellite TV broadcast and terrestrial TV broadcast.

[Configuration example of double tuner module]
As shown in FIG. 10, the double tuner module 110 shows an example in which the double tuner module 110 is designed with a height of 2.3 mm as a thinner thickness on the tuner substrate 111.
The double tuner module 110 configured as a thin module is configured such that a satellite tuner 112 and a terrestrial tuner 113 are mounted as an IC on a tuner substrate 111 and covered with a shield case 114 as a shield part.
Thus, in order to realize a thin tuner, an integrated IC is preferable in the semiconductor to be used.
In order to improve the degree of integration, the satellite tuner 112 and the terrestrial tuner 113 of the present embodiment incorporate a local oscillator and an inductor used therefor as shown in FIG. 4, for example.
Moreover, the code | symbol 115 in FIG. 10 has shown the copper foil surface which is a ground surface.

As shown in FIG. 10, the double tuner module 110 has a satellite case IC 112 formed by an IC and a shield case 114 positioned above the terrestrial tuner IC 113, and has a size of ½ or more of the IC shape size. Openings 116A and 116B are formed.
The openings 116A and 116B are formed so that the electric field and magnetic field generated in the shield case 114 can be efficiently discharged to the outside.
As can be seen from FIG. 10, the use of the shield case 114 with openings formed on the satellite tuner IC 112 and the terrestrial tuner IC 113 can prevent the stray capacitance shown in FIG.
In the double tuner module 110 having this structure, even when a plurality of tuner ICs that cannot take a sufficient distance compared with the wavelength of the oscillation frequency of the VCO are mounted, it is possible to avoid interference of high-frequency signals with each other.
The size, shape, function, and the like of the opening 116 of the high-frequency module (in this embodiment, a double tuner module) will be described in detail later.

The shield case 114 according to the first embodiment is made of a thin material and a metal called “white”, which is an alloy of copper, nickel, and zinc, which is excellent in solderability.
However, as the shield case 114, there is generally no problem as long as the conductivity is excellent. Therefore, an inexpensive tin plate or a similar product can be used when the shape restriction is loose.

Further, the inductor used for the oscillator built in the IC is configured to have concentric wiring.
In addition, an inductor used in an oscillator with a built-in IC is configured to have a plurality of concentric wirings.
For example, it is possible to form a spiral inductor on the mask pattern inside the IC.
The IC can also employ a structure in which concentric inductors are arranged in a wiring pattern, an electronic component, or a wiring.

[Functional explanation of double tuner module]
Here, the circuit configuration and functions in the double tuner module 110 will be described with reference to FIG.
Here, the double tuner module is denoted by reference numeral 200.

The double tuner module 200 of FIG. 11 includes an input terminal 201, a branching circuit 202, a high pass filter (HPF) 203, a low noise amplifier (LNA) 204, a satellite tuner 205, and a satellite demodulation unit 206. Have
The double tuner module 200 includes a band pass filter (BPF) 207, an attenuator circuit (ATT) 208, an LNA 209, a terrestrial tuner 210, and a terrestrial demodulation unit 211.
The double tuner module 200 includes an output matrix unit 212, switches 213 and 214, and transport stream (TS) output ports 215 and 216.
The double tuner module 200 has an inductor 217 and a low noise block down converter (LNB) terminal 218.
Double tuner module 200 has VCCA1 terminal 219 for satellite tuner and VCCA2 terminal 220 for terrestrial tuner as power terminals.
The double tuner module 200 has a VDDH terminal 221 and a VDDL terminal 222 for satellite and terrestrial demodulation and output matrix.
The double tuner module 200 has an I ² C terminal 223.

In the double tuner module 200, the HPF 203, the LNA 204, the satellite tuner 205, and the satellite demodulation unit 206 form a satellite broadcast receiving circuit 230.
The BPF 207, the attenuator circuit 208, the LNA 209, the terrestrial tuner 210, and the terrestrial demodulation unit 211 form a terrestrial broadcast receiving circuit 240.

In the double tuner module 200, the high frequency signal applied to the input terminal 201 is separated into a satellite broadcast receiving side and a terrestrial broadcast receiving side by a branching circuit 202.
In the satellite broadcast receiving circuit 230, the satellite broadcast signal is amplified by the LNA 204 via the HPF 203, input to the satellite tuner 205, and frequency-converted. Thereafter, the satellite demodulating unit 206 transmits the TS data to the output matrix unit 212.

On the other hand, in the terrestrial broadcast receiving circuit 240, the terrestrial broadcast signal is demultiplexed by the demultiplexing circuit 202, band-limited by the BPF 207, adjusted to an appropriate signal level by the attenuator circuit 208, amplified by the LNA 209, and terrestrial Input to the tuner 210.
After the frequency is changed by the terrestrial tuner 210, the terrestrial demodulator 211 converts the TS data to the same TS data as the satellite demodulator, and sends it to the output matrix unit 212 as described above.
The output matrix unit 212 includes switches 213 and 214, and can select and output the TS required for the TS output ports 215 and 216.

The inductor 217 has a role of DC supply to the LNB and cutoff of the high frequency signal. The inductor 217 is connected to the terminal 218 and the satellite line of the branching circuit (distributor) 202, and passes through the branching circuit 202 in a DC manner for input. A DC voltage is supplied from the terminal 201 to the outside.
The terminal 223 is an input terminal of an I ² C bus that controls the satellite demodulation unit 206 and the terrestrial demodulation unit 211, respectively, and is configured to control the satellite tuner 205 and the terrestrial tuner 210 through the respective demodulation units. ing.

The overall configuration of the broadcast signal receiving apparatus 100 according to the present embodiment has been described above centering on the double tuner module 110 that is an example of a high-frequency module.
Below, the characteristic of the high frequency module which has an opening part concerning this embodiment is explained.

[Description of the principle of a high-frequency module having an opening]
FIGS. 12A and 12B are views for explaining the principle of the high-frequency module having an opening according to the first embodiment.
Here, in order to facilitate understanding, the same components as the double tuner module are represented by the same reference numerals.
In FIG. 12A, 300 indicates an IC incorporating an oscillator including an inductor, and 301 indicates a radio wave.
In FIG. 12B, reference numeral 400 denotes a magnetic field.

FIG. 12A shows radio wave radiation by the high-frequency module in the present embodiment.
As the radio wave 301 is radiated to the outside from the opening part 116 of the shield case 114 having the opening part of the present embodiment, the opening part 116 is formed with its position and opening degree determined, so that the radio wave 301 is shielded from the shield case. No reflection occurs at 114, and no lateral propagation occurs.

In FIG. 12B, similarly, the opening 116 is formed with its position and opening ratio determined so that the shield case 114 having the opening 116 does not generate an eddy current with respect to the magnetic field 400.
This opening 116 diffuses the magnetic field 400 to the outside of the module, and can prevent the generation of eddy currents propagating through the shield case 114.

Based on the above principle, the double tuner module 110 using the shield case of FIG. 10 is formed.
As described above, as is apparent from FIG. 10, the stray capacitance shown in FIG. 7 is prevented from being generated by using the shield cases provided with openings on the upper surfaces of the satellite tuner IC 112 and the terrestrial tuner IC 113. I understand.
In the tuner module having this structure, even when a plurality of tuner ICs that cannot take a sufficient distance compared with the wavelength of the oscillation frequency of the VCO are mounted, it is possible to avoid interference of high-frequency signals with each other.

  FIGS. 13A and 13B are views for explaining a specific configuration example of the opening formed in the shield case 114 according to the present embodiment.

FIG. 13A shows an example in which square holes are formed as openings 116C and 116D on the upper surface of the mounted IC, and the center position is the same as each IC.
The aperture ratio is significant when the size has one side or more of each side of the chip size of the IC. The aperture ratio in this case is (1/2) ² = 1/4 or more. Desirably, it is 25% or more of the IC size.
In this example, the size of the square hole is 4.7 mm × 4.7 mm, and the size of the tuner IC is 4.3 mm × 4.3 mm.
The shield case 114 has a size of 23 mm × 23 mm.

In FIG. 13B, the shape of the openings 116E and 116F of the shield case 114 of the present embodiment is a round hole shape.
In this case, a sufficient effect can be expected if the aperture ratio is 25% or more of the IC size.
In this example, the diameters of the round hole-shaped openings 116E and 116F are 6 mm.

  FIGS. 14A and 14B are diagrams for explaining another specific configuration example of the opening formed in the shield case 114 according to the present embodiment.

In FIG. 14A, square holes corresponding to the configuration example of FIG. 13A are denoted by reference numerals 116C and 116D. In this example, an elliptical oblong hole opening 116G including both of them is shown. Is formed.
Also with this configuration, the generation of stray capacitance described above can be avoided, so that mutual interference of high-frequency signals can be prevented.

Similarly, in the example of FIG. 14B, the rectangular hole portions 116C and 116D are included in the opening portion 116H of the elongated hole,
FIG. 14C is an example of a plurality of holes under the condition that the same center as the position of the IC is not taken by the openings 116I and 116J of the same hole.
FIG. 14D shows a case where only one opening 116K is provided.

  In the tuner module having the above configuration, the actual performance difference appears in the bit error rate (BER).

FIG. 15 is a diagram illustrating an example in which interference from a terrestrial tuner to a satellite tuner is measured.
In FIG. 15, the horizontal axis indicates the channel name, and the vertical axis indicates the CN value.
The CN ratio on the vertical axis is shown normalized by the ratio of Carrier to Noise of the input signal necessary to achieve a very good BER called required CN.
In FIG. 15, the characteristic indicated by A is a case where two holes having an opening are formed, the characteristic indicated by B is a case where one hole being an opening is formed, and the characteristic indicated by C is an opening. This is a case where a certain hole is not formed.

In particular, the effect of holes near the BS15 channel used in Japanese satellite broadcasting is shown.
When two holes that are openings are formed, interference can be sufficiently suppressed.
Even when only one hole, which is an opening, is formed, the interference suppressing effect is sufficiently exhibited as compared with the case where no hole is formed.

That is, the required CN in FIG. 15 is the result of countermeasures at a local frequency 2636 MHz that is twice the input frequency 1318 MHz near the BS-15 channel, and is most suitable when the number of holes is the same as the number of ICs to be mounted. It shows that the effect comes out.
Of course, it is obvious that only one is effective.

<2. Second Embodiment>
FIG. 16 is a diagram illustrating a configuration example of a double tuner module in the broadcast signal receiving apparatus according to the second embodiment of the present invention.

  The double tuner module 110A according to the second embodiment is different from the double tuner module 110 according to the first embodiment in that a conductive paste 117 is applied as a shield portion instead of the shield case to form a conductive coating film. It is to be formed by.

That is, the double tuner module 110A protects the periphery of the satellite tuner IC 112 and the terrestrial tuner IC 113 mounted on the tuner substrate 111 with the mold filler 118.
The double tuner module 110A has a structure having the same effect as the shield case described above by applying the conductive paste 117 to the outer periphery of the seal.
At that time, an opening 116A and an opening 116B are formed in the coating film 117A of the conductive paste 117 that performs the same action as the shield case so that radio waves and magnetic lines of force are discharged to the outside of the shield body by the conductive paste.
Since the detailed operation principle is the same as that when the shield case is used, the description thereof is omitted here.
The ground surface 115 on the substrate 111 and the conductive paste 117 are electrically connected at the wall surface to constitute a shield body.

As described above, according to the present embodiment, the following effects can be obtained. The electric field and the magnetic field can be discharged to the outside of the shield part, the electronic components in the shield part can be arranged closer to each other, and the size can be reduced.
For example, this is effective when a satellite tuner IC or a terrestrial tuner IC using a shield case incorporates an oscillator such as a VCO using a spiral inductance.
In other words, the electric field and magnetic field radiated by the oscillation circuit are close enough that it is not negligible to generate spurious noise or deteriorate the phase noise of the oscillator by electromagnetic coupling or magnetic coupling of the surrounding circuits. Effective when mounted.
In particular, since the shield case is attached, the above-mentioned noise group that is generated more strongly can be radiated to the outside of the shield portion, so that it is possible to arrange components that are very close to each other.
In particular, when a plurality of tuners are configured on the same substrate, the effect is the same as that of discharging the electric field and magnetic field to the outside of the shield part, and is particularly noticeable when operated simultaneously.
It is also effective when using independent oscillators with transmission and reception functions like a transceiver.
Furthermore, even if there is only one oscillator, noise can be generated in a separate path to the mixer circuit or the input circuit. Therefore, an effect can be expected by providing a shield part structure having this opening.
In addition, it is also effective for a transmitter / receiver having a plurality of bands such as 2.4 GHz band and 5 GHz band such as a wireless LAN.

The semiconductor to which this configuration is applied includes a monolithic IC in which a spiral inductance is built in the mask pattern of the IC.
Further, it includes an IC having an inductance configured on a small substrate on which a silicon bare chip called SIP (System In Package) is mounted.
Alternatively, an IC using spiral inductance is included as a normal external device. Any of these ICs is effective and can be adapted.

  DESCRIPTION OF SYMBOLS 100 ... Broadcast signal receiver 110 ... Double tuner module 111 ... Tuner board | substrate 112 ... Satellite tuner IC, 113 ... Terrestrial tuner IC, 114 ... Shield case, 116, 116A to 116K, opening, 117, conductive paste, 120, input terminal, 130, PCI-Express bridge, 140, power supply, 150, memory, 160, card Edge connector part.

Claims (12)

An integrated circuit with a built-in oscillator;
A shield portion that covers the integrated circuit,
The shield part is
A high frequency module, wherein an opening having a size equal to or larger than a half of a shape size of the integrated circuit is formed in a region facing the arrangement position of the integrated circuit. A plurality of the integrated circuits,
The shield part is
The high-frequency module according to claim 1, wherein an opening having a size equal to or larger than ½ of a shape size of the integrated circuit is formed in a region facing the arrangement position of at least one integrated circuit. The shield part is
The high-frequency module according to claim 2, wherein an opening having a size equal to or larger than ½ of the shape size of each integrated circuit is formed in each region facing the arrangement positions of the plurality of integrated circuits. The shield part is
An opening is formed in the shape of a long hole in a shape including the opening having a size of 1/2 or more of the shape size of each integrated circuit over a region facing the arrangement position of the plurality of integrated circuits. 2. The high frequency module according to 2. The plurality of integrated circuits are:
A satellite tuner integrated circuit for processing satellite wave broadcast signals;
A high-frequency module according to any one of claims 2 to 4, further comprising: a terrestrial tuner integrated circuit that processes a terrestrial broadcast signal. The shield part is
The high frequency module according to claim 1, wherein the high frequency module is formed of a metal shield case. The shield part is
The high frequency module according to claim 1, wherein the high frequency module is formed of a conductive coating film. An input terminal for inputting a satellite broadcast signal or a terrestrial broadcast signal;
A satellite broadcast receiving circuit including a satellite tuner having a frequency conversion function of the satellite wave broadcast signal;
A terrestrial broadcast receiving circuit including a terrestrial tuner having a frequency conversion function of the terrestrial broadcast signal;
A demultiplexing circuit that distributes the satellite wave broadcast signal input from the input terminal to the satellite broadcast reception circuit, and demultiplexes the terrestrial broadcast signal to the terrestrial broadcast reception circuit;
The satellite tuner and the terrestrial tuner are
Built-in oscillator, formed as satellite tuner integrated circuit and terrestrial tuner integrated circuit,
Including at least a shield portion shaped to cover the satellite tuner integrated circuit and the terrestrial tuner integrated circuit,
The shield part is
An opening having a size equal to or larger than ½ of the shape size of the integrated circuit is formed in a region facing an arrangement position of at least one of the satellite tuner integrated circuit and the terrestrial tuner integrated circuit. The receiving device. The shield part is
9. The reception according to claim 8, wherein an opening having a size equal to or larger than a half of a shape size of each integrated circuit is formed in a region facing an arrangement position of the satellite tuner integrated circuit and the terrestrial tuner integrated circuit. apparatus. The shield part is
An opening in the shape of a long hole including the opening having a size of 1/2 or more of the shape size of each integrated circuit over a region facing the arrangement position of the satellite tuner integrated circuit and the terrestrial tuner integrated circuit. The receiving device according to claim 8. The shield part is
The receiving device according to claim 8, wherein the receiving device is formed by a metal shield case. The shield part is
The receiving apparatus according to claim 8, wherein the receiving apparatus is formed of a conductive coating film.

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