JP2013141097A - High frequency module and electronic apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve high RF performance.SOLUTION: A high frequency module 10 with a rectangular circuit board 30 comprises: an input section 20 for inputting an RF signal on the circuit board 30; a reception circuit section 22 that receives the RF signal supplied from the input section 20; and a transmission line 21 for transmitting the RF signal from the input section 20 to the reception circuit section 22. The transmission line 21 is linear and has the shortest transmission line length that connects the input section 20 with the reception circuit section 22.

Description

  The present invention relates to a high-frequency module and an electronic device including the high-frequency module.

  Various types of digital terrestrial televisions and Blu-ray disc recorders with different performances are known. For tuners used in such devices, for example, tuners configured to cover a circuit board on which discrete components are mounted with a metal case have been used. As a result, ICs have been integrated.

  Conventionally, a resin mold type module package in which electronic components on a substrate are sealed with a resin mold, and a module in which a tuner circuit and a demodulation circuit are shielded are known (see, for example, Patent Documents 1 and 2). .

JP 2002-261200 A JP 2011-187777 A

  However, in the module as shown in the above-described prior art, the quality of the RF (Radio Frequency) part included in the integrated tuner part cannot be ensured, and the RF performance cannot be improved. It was.

  SUMMARY An advantage of some aspects of the invention is that it provides a high-frequency module that improves RF performance and an electronic device including the high-frequency module.

  In order to achieve the above object, the present invention provides a high frequency module (10) having a rectangular circuit board (30), and an input unit (20) for inputting an RF signal on the circuit board (30). A receiving circuit unit (22) for receiving an RF signal supplied from the input unit (20), and a transmission line (21) for transmitting the RF signal from the input unit (20) to the receiving circuit unit (22). The transmission line (21) is linear and has the shortest transmission line length connecting the input unit (20) and the receiving circuit unit (22).

  Moreover, this invention is an electronic device (100) containing the high frequency module (10) mentioned above.

  In addition, the said reference code is a reference to the last, and this invention is not limited to the aspect of illustration by this.

  According to the present invention, it is possible to improve the RF performance.

It is a figure which shows schematic structure of the electronic device containing the high frequency module which concerns on this embodiment. It is a figure which shows the circuit block of the high frequency module which concerns on this embodiment. It is a figure explaining the layout of the surface layer of the circuit board concerning this embodiment. It is a figure explaining the layout of the 2nd layer of the circuit board concerning this embodiment. It is a figure explaining the layout of the 3rd layer of the circuit board concerning this embodiment. It is a figure explaining the layout of the 4th layer of the circuit board concerning this embodiment. It is a figure explaining the manufacturing method of the high frequency module concerning this embodiment.

  Next, the form for implementing this invention is demonstrated.

<Schematic configuration of electronic equipment including high-frequency module>
FIG. 1 is a diagram illustrating a schematic configuration of an electronic device including the high-frequency module according to the present embodiment. As shown in FIG. 1, an electronic device 100 according to the present embodiment is, for example, a terrestrial digital television or a disk recorder, and is configured to include a high-frequency module 10, an external connector 11, and a line 12. Electronic device 100 includes, for example, a demodulator, a display device, an audio device, and the like when used as a terrestrial digital television in addition to the above-described configuration. In addition, when the electronic device 100 is used as a disk recorder, the electronic device 100 includes, for example, a demodulator, a recording / playback apparatus, and the like.

  The high frequency module 10 receives the RF signal supplied from the antenna 13 via the external connector 11 and the line 12.

  The external connector 11 outputs an RF signal supplied from the antenna 13 to the line 12. Note that the external connector 11 is preferably provided, for example, on an extension of the line 21 included in the high-frequency module 10 described later.

  The line 12 is a straight line connecting the external connector 11 and the high frequency module 10. The line 12 performs impedance matching between the external connector 11 and an input unit 20 of the high-frequency module 10 described later, and transmits an RF signal to the high-frequency module 10.

  The high-frequency module 10 is configured to include an input unit 20, a transmission line 21, a receiving circuit unit 22, and a crystal oscillator 23.

  The input unit 20 outputs an RF signal input via the external connector 11 and the line 12 to the transmission line 21. The input unit 20 is configured to include a filter 24 and a balun 25.

  The transmission line 21 transmits the RF signal output from the input unit 20 to the reception circuit unit 22. Here, in order to improve the transmission performance of the RF signal to the reception circuit unit 22, the transmission line 21 is linear and is configured to have the shortest transmission line length connecting the input unit 20 and the reception circuit unit 22. . The configuration of the transmission line 21 will be described later.

The reception circuit unit 22 is configured to include a variable frequency oscillation circuit 26, an amplifier 27, and a mixer 28. The receiving circuit unit 22 converts the RF signal obtained from the transmission line 21 into an IF (Intermediate Frequency) signal and outputs it, for example, according to a control signal output from an I ² C (Inter-Integrated Circuit) interface. To do. The receiving circuit unit 22 is supplied with predetermined power necessary for the operation of the receiving circuit unit 22.

  The crystal oscillator 23 oscillates at a reference frequency determined by a crystal resonator.

  The filter 24 is, for example, a notch filter that removes a specific frequency component from the input RF signal, and outputs the RF signal from which the specific frequency component is removed to the balun 25. The configuration of the filter 24 will be described later.

  The balun 25 converts the unbalanced RF signal supplied from the filter 24 into a balanced RF signal and outputs it to the transmission line 21.

  The variable frequency oscillation circuit 26 generates a local oscillation frequency based on the output from the crystal oscillator 23 and supplies the generated local oscillation frequency to the mixer 28.

The amplifier 27 amplifies the balanced RF signal obtained from the transmission line 21 and supplies the amplified RF signal to the mixer 28. The mixer 28 receives the local oscillation frequency supplied from the variable frequency oscillation circuit 26 and the amplifier 27. The supplied RF signal is mixed and an IF signal is output.

The variable frequency oscillation circuit 26 and the crystal oscillator 23 described above are configured as a part of the PLL circuit, and the frequency division ratio of the PLL circuit is controlled by a control signal from I ² C so that the predetermined frequency is changed to the variable frequency. The signal may be output from the oscillation circuit 30.

<Circuit block of high frequency module>
Next, the circuit block of the high frequency module 10 described above will be described. FIG. 2 is a diagram illustrating a circuit block of the high-frequency module according to the present embodiment. As shown in FIG. 2, the high frequency module 10 is mounted on a circuit board 30.

  The circuit board 30 is composed of a rectangular (for example, square) multilayer board. The circuit board 30 is composed of, for example, a four-layer board.

  On the circuit board 30, an input unit 20, a transmission line 21, a receiving circuit unit 22, a crystal oscillator 23-1 constituting a crystal oscillator 23, and a power supply or control electrical component 29 are formed. Yes. For example, on the circuit board 30, the receiving circuit unit 22, the crystal resonator 23-1, and the like are formed in the receiving circuit mounting region 30-1 including one side of the circuit board 30, and the input unit 20, the transmission line 21, and the like. Is formed in the input portion mounting region 30-2 including the other side opposite to the one side.

  In the present embodiment, a receiving circuit mounting region 30-1 and an input unit mounting region 30-2 are provided on the circuit board 30 and the component mounting region is divided, so that an RF signal to the receiving circuit unit 22 as described later is provided. Signal transmission performance can be improved.

  In the region of the input unit 20, two Zener diodes D1, a filter 24, and a balun 25 are connected in series with the ground.

  The filter 24 is configured as a notch filter (trap filter) including capacitors C1 to C3, and a coil L1 and a coil L4. In addition, these electrical components (that is, the capacitors C1 to C3, the coil L1, and the coil L4) are arranged along the side of the circuit board 30.

  The transmission line 21 is formed between the balun 25 and the receiving circuit unit 22, and coils L2 to L3 and capacitors C4 to C5 are arranged on the transmission line 21 as impedance matching electrical components. . As a result, the transmission line 21 performs impedance matching for reducing the insertion loss to the receiving circuit unit 22 with respect to the balanced RF signal converted by the balun 25, and transmits the RF signal to the receiving circuit unit 22.

  In addition, the electrical parts (that is, the coils L2 to L3 and the capacitors C4 to C5) on the transmission line 21 have an input part to which an RF signal is input and an output part to which the RF signal is output in a linear shape of the transmission line 21. It is arranged along.

  Further, the electrical components on the transmission line 21 are arranged so as to have the shortest transmission line length connecting the balun 25 and the receiving circuit unit 22. The electrical components on the transmission line 21 are chip components having a rectangular parallelepiped shape, and are arranged along the transmission line 21 so that the longitudinal direction of each electrical component is parallel to the transmission line 21. Thereby, the loss of the RF signal is minimized, and the transmission performance of the RF signal to the receiving circuit unit 22 is improved.

  The crystal resonator 23-1 that constitutes the crystal oscillator 23 is disposed in a region opposite to one side of the circuit board 30 on which the input unit 20 is disposed. As a result, it is possible to reduce the influence on the RF signal input to the input unit 20 caused by the oscillation from the crystal resonator 23-1.

  The power supply or limiting electrical components 29-1 to 29-2 are electrical components for supplying power or inputting control signals, and are arranged around the reception circuit unit 22.

  As described above, the high-frequency module 10 according to the present embodiment includes the receiving circuit unit according to the arrangement of the input unit 20, the transmission line 21, the receiving circuit unit 22, and the crystal resonator 23-1 in the circuit board 30. The reception performance of the RF signal at 22 can be improved.

<Layout of each layer of circuit board 30: surface layer (first layer)>
Next, the layout of each layer constituting the circuit board 30 described above will be described. FIG. 3 is a diagram for explaining the layout of the surface layer (first layer) of the circuit board according to the present embodiment.

  As shown in FIG. 3, on the surface layer 30A of the circuit board 30, as described above, the input unit 20, the transmission line 21, the reception circuit unit 22, the crystal resonator 23-1, and the power supply or control electrical component. 29 is implemented. The receiving circuit unit 22 includes an IC unit 22-1 and a terminal unit 22-2.

  A GND pattern (ground pattern) 31A is formed on the surface layer 30A of the circuit board. For example, the GND pattern 31A is formed over the entire area excluding the area necessary for component mounting. Here, the GND pattern 31A-1 adjacent to the transmission line 21 is arranged so as to be separated from the transmission line 21 so as to provide a certain distance (for example, arrows d1 and d2 shown in FIG. 3).

  As described above, by arranging the GND pattern 31A-1, a predetermined impedance in the transmission line 21 can be secured.

<Layout of each layer of circuit board 30: second layer>
Next, FIG. 4 is a diagram for explaining the layout of the second layer of the circuit board according to the present embodiment.
The second layer 30B of the circuit board 30 constitutes a layer below the surface layer 30A of the circuit board 30 shown in FIG. 3 when the layers 30A to 30D of the circuit board 30 are overlapped.

  As shown in FIG. 4, a GND pattern 31 </ b> B and a through hole 32 are formed in the second layer 30 </ b> B of the circuit board 30. The GND pattern 31B shown in FIG. 4 is formed on the entire surface except the region where the through hole 32 shown in FIG. 4 is formed.

  Note that the through hole 32 shown in FIG. 4 is used to electrically connect terminals provided in the respective layers 30 </ b> A to 30 </ b> D constituting the circuit board 30, for example.

  By the second layer 30B of the circuit board 30 described above, it is possible to suppress the influence of noise on the receiving circuit section 22 of the surface layer 30A that is generated from a power supply pattern or the like formed on the third layer 30C of the circuit board 30 described later. It becomes.

<Layout of each layer of circuit board 30: third layer>
Next, FIG. 5 is a diagram for explaining the layout of the third layer of the circuit board according to the present embodiment. As shown in FIG. 5, a GND pattern 31 </ b> C, a through hole 32 </ b> C, and a power supply pattern (power supply wiring) 40 are formed in the third layer 30 </ b> C of the circuit board 30.

  Here, when the power supply pattern 40-1 and the power supply pattern 40-2 are overlapped with each layer (30A to 30D) of the circuit board 30, the area of the IC part 22-1 in the reception circuit part 22 of the surface layer 30A. It is formed in a region avoiding the region 22C of the overlapping third layer 30C. The power supply pattern 40-1 and the power supply pattern 40-2 are arranged so as to surround the region 22C.

  The power supply pattern 40-1 and the power supply pattern 40-2 supply power to the receiving circuit unit 22 mounted on the surface layer 30A.

  Further, GND patterns 31C-1 to 31C-3 are formed around the power supply pattern 40-1 and the power supply pattern 40-2.

  As described above, since the power supply pattern 40 is formed in a region avoiding the region 22C, it is possible to suppress the influence of noise from the power supply pattern 40 to the receiving circuit unit 22 on the surface layer 30A. In addition, it is possible to suppress interference between the second layer 30B and the fourth layer 30D of the circuit board 30 by the arrangement of the GND patterns 31C-1 to 31C-3.

<Layout of each layer of circuit board 30: fourth layer>
Next, FIG. 6 is a diagram for explaining the layout of the fourth layer (the back surface of the circuit board) of the circuit board according to the present embodiment. As shown in FIG. 6, the fourth layer 30D of the circuit board 30 includes a GND pattern 31D, an input terminal 41, a power supply terminal 42, a GND terminal 43, an output terminal 44, and a control signal terminal 45. Is formed.

  For example, the RF signal transmitted from the transmission line 21 described above is input to the input unit 20 of the surface layer 30 </ b> A through the through hole 32 of each layer via the input terminal 41. In addition, power to the receiving circuit unit 22 on the surface layer 30 </ b> A is input through the power terminal 42 and supplied through the power pattern 40 and the through hole 32.

  The GND pattern 31 formed in each layer is grounded through the GND terminals 43-1 to 43-13.

  As described above, the high-frequency module 10 of this embodiment is formed so that the circuit board 30 has a square shape. Therefore, for example, when the high frequency module 10 is mounted on the electronic device 100 or the like, the power supply terminal 42, the GND terminal 43, the output terminal 44, and the control signal terminal 45 are soldered onto a circuit board such as the electronic device 100 or the like. The stress becomes even. Thereby, the high frequency module 10 can be reliably mounted on a circuit board such as the electronic device 100.

<High-frequency module manufacturing method>
Next, a method for manufacturing the above-described high-frequency module 10 will be described. FIG. 7 is a view for explaining the method for manufacturing the high-frequency module according to the present embodiment. The high-frequency module 10 in the present embodiment is manufactured by the steps shown in FIGS.

  In the step shown in FIG. 7A, the above-described mounting components (for example, the electrical components constituting the input unit 20 and the transmission line 21, the IC of the receiving circuit unit 22, the crystal resonator 23- 1)).

  Next, in the step shown in FIG. 7B, the entire substrate on which the above-described mounting components are mounted is transfer-molded by resin molding. Here, for example, a thermoplastic resin may be used for the resin mold.

  Next, in the step shown in FIG. 7C, a dicing line on the transfer-molded substrate is diced (cut) into pieces by using a dicing blade.

  Next, in the step shown in FIG. 7D, aluminum is deposited on the surface of the separated module by vapor deposition (for example, ion plating), and an aluminum layer is formed on the top and side surfaces of the separated module. And make it a shield.

  Next, in the step shown in FIG. 7E, a resist is printed on the lower surface of the module on which aluminum is deposited. Next, in the step shown in FIG. 7F, the resist is laser-marked with a laser to engrave characters (such as a model number) and inspected.

  As described above, according to the embodiment of the present invention, it is possible to improve the RF performance by arranging each electrical component mounted on the circuit board and the GND pattern formed on the circuit board. In addition, a multi-tuner can be realized by a high-frequency module with improved RF performance.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Can be changed.

DESCRIPTION OF SYMBOLS 10 High frequency module 11 External connector 12 Line 13 Antenna 20 Input part 21 Transmission line 22 Reception circuit part 22-1 IC part 22-2 Terminal part 23 Crystal oscillator 23-1 Crystal oscillator 24 Filter 25 Balun 26 Variable frequency oscillation circuit 27 Amplifier 28 mixer 29 power supply circuit section 30 circuit board 30-1 receiving circuit mounting area 30-2 input section mounting area 30A surface layer (first layer)
30B Second layer 30C Third layer 30D Fourth layer 31 GND pattern 32 Through hole 40 Power supply pattern 41 Input terminal 42 Power supply terminal 43 GND terminal 44 Output terminal 45 Control signal terminal 100 Electronic device

Claims (13)

A high-frequency module having a rectangular circuit board,
On the circuit board,
An input unit for inputting an RF signal;
A receiving circuit unit that receives an RF signal supplied from the input unit;
A transmission line for transmitting the RF signal from the input unit to the receiving circuit unit;
The transmission line is
A high-frequency module which is linear and has a shortest transmission line length connecting the input unit and the receiving circuit unit.   The high-frequency module according to claim 1, wherein an electrical component is disposed on the transmission line. The electrical component is
The high-frequency module according to claim 2, wherein an input unit to which the RF signal is input and an output unit to which the RF signal is output are arranged along the transmission line. The electrical component has a substantially rectangular parallelepiped shape,
4. The high-frequency module according to claim 2, wherein the electrical component is disposed along the transmission line so that a longitudinal direction of the electrical component is substantially parallel to the transmission line. 5. A ground pattern on the circuit board;
The ground pattern is
5. The high-frequency module according to claim 1, wherein the high-frequency module is disposed so as to be spaced apart from the transmission line by a certain distance. The receiving circuit has an oscillation unit,
Having a crystal resonator for determining the frequency of the oscillation unit on the circuit board;
The crystal resonator is
The high-frequency module according to claim 1, wherein the high-frequency module is disposed on a side opposite to one side of the circuit board on which the input unit is disposed. The receiving circuit unit includes an IC unit and a terminal unit,
The power supply wiring for supplying power to the receiving circuit unit is:
Arranged to surround the IC part,
The high-frequency module according to claim 1, wherein the ground pattern is formed around the power supply wiring.   8. The high-frequency module according to claim 1, wherein the RF signal is supplied to the input unit via an external connector provided on an extension line of the transmission line. 9.   The notch filter which removes a specific frequency component from the RF signal is disposed along the side of the circuit board on which the input unit is disposed. The high frequency module described in 1.   The high-frequency module according to claim 1, wherein the circuit board includes a square shape. The receiving circuit unit is
Formed in a region including one side of the circuit board;
The input unit is
The high-frequency module according to claim 1, wherein the high-frequency module is formed in a region including the other side opposite to the one side.   The electronic device containing the high frequency module as described in any one of Claims 1 thru | or 11. An external connector to which an RF signal is supplied from an antenna;
The external connector is
The electronic apparatus according to claim 12, wherein the electronic apparatus is provided on an extension line of the transmission line.

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