JP4586522B2 - Tuner device - Google Patents

Description

  The present invention relates to a tuner device suitable for use in, for example, a BS digital satellite broadcast receiver.

  In recent years, the progress of semiconductor technology has been remarkable, and a large number of small high-frequency integrated circuit elements capable of processing a frequency of several GHz band have been developed. A tuner device applicable to, for example, a BS digital satellite broadcast receiver that incorporates not only a high-frequency amplifier and mixer but also an electronically tuned PLL (phase-locked loop) oscillator (high-frequency oscillator) in the small-sized high-frequency integrated circuit element thus developed. There is something that can be used.

  By the way, this small high-frequency integrated circuit element generates very large heat due to the integration of the circuit and high-frequency operation.

  Therefore, when a tuner device is configured using this small high-frequency integrated circuit element, a heat exhaust structure is required.

Conventionally, as a tuner device provided with an exhaust heat structure, as shown in FIGS. 7 and 8, in order to dissipate heat generated by the integrated circuit element 3 mounted on the circuit board 2 disposed in the metal shield case 1 of the tuner device, The one side metal case cover 1a is provided with a tongue piece 4 by cutting corresponding to the integrated circuit element 3 mounted on the circuit board 2, and the tongue piece 4 is pressed against the upper surface of the integrated circuit element 3. Has been proposed in which heat is radiated by the metal case cover 1a through the metal tongue 4 (Patent Document 1).
Japanese Patent Laid-Open No. 2001-244689

  By the way, when the exhaust heat structure as shown in Patent Document 1 is applied to a tuner device in which a high-frequency integrated circuit element incorporating a high-frequency oscillator is mounted, the tongue piece 4 of the one-side metal shield case 1a is metal, and this tongue piece 4 Causes inductive coupling or capacitive coupling with the inductance constituting the high frequency oscillator built in the upper surface side of this high frequency integrated circuit element, which causes the inductance value to change, and the phase noise due to the shift of the oscillation frequency range and the decrease of the Q value There is a disadvantage that high frequency characteristics are deteriorated.

  Furthermore, when, for example, two high-frequency integrated circuit elements are shielded from each other in this metal shield case, and two tuners are arranged in parallel, for example, the high-frequency oscillation power induced in the tongue 4 There is a disadvantage in that the high frequency characteristics deteriorate due to the mutual influence of the radiation.

  In view of this point, an object of the present invention is to maintain good high-frequency characteristics and exhaust heat well.

A tuner device according to the present invention is a tuner device on which a high-frequency integrated circuit element having a built-in high-frequency oscillator is mounted. The tuner device is fixed in a metal shield case and the metal shield case, and the high-frequency integrated circuit element is mounted on one surface. A printed wiring board to be mounted, provided at a position where the high-frequency integrated circuit element is mounted, penetrating from the one surface of the printed wiring board to the other surface, and from a mounting area of the high-frequency integrated circuit element A printed wiring board having a through hole having a small hole area; and a heat radiating sheet that is provided on the other surface of the printed wiring board through the through hole and is in contact with the metal shield case.

  According to the present invention, a heat radiating sheet is provided through the through hole of the printed wiring board, and the heat of the high frequency integrated circuit element is conducted from the heat radiating sheet on the other side of the printed wiring board to the metal shield case to radiate heat. Exhaust heat can be performed.

  Further, according to the present invention, the heat radiation sheet is brought into contact with the substrate side of the high frequency integrated circuit element that is less affected by the high frequency signal, and the heat of the high frequency integrated circuit element is transferred from the heat radiation sheet on the other side of the printed wiring board to the metal shield case. Since it conducts and dissipates heat, the inductance for the high-frequency oscillator of this high-frequency integrated circuit element is not inductively coupled or capacitively coupled to the heat-dissipating sheet and is not subject to high-frequency radiation, so that high-frequency characteristics can be maintained well.

  Hereinafter, an example of the best mode for carrying out the tuner device of the present invention will be described with reference to the drawings. This example is a tuner device provided with two tuners that can simultaneously receive two channels of BS digital satellite broadcasting.

  The appearance of the tuner device according to this example is shown in FIG. 2, where FIG. 2A is a top view, FIG. 2B is a bottom view, and FIG. 2C is a side view. In FIG. 2, 10 is a metal shield case, 10a is an upper case of this metal shield case 10, and this upper case 10a is provided with a predetermined air hole 10b. Reference numeral 10 c denotes a lower case of the metal shield case 10.

  In FIG. 2, reference numeral 11 denotes an input terminal for a high frequency signal of, for example, 1 to 2 GHz of a BS digital satellite broadcast signal from an antenna, and 12 denotes an input / output pin. A printed wiring board 13 provided with predetermined wiring is fixed at an intermediate position between the upper case 10a and the lower case 10c in the metal shield case 10.

  FIG. 3A is a plan view showing a state where the upper case 10a as shown in FIG. 3B of the tuner device according to this example is removed. In this example, the printed wiring board 13 of the first shield chamber 14a following the input terminal 11 is shown. A distributor 15 is mounted on one side surface.

  Following the first shield chamber 14a, second and third shield chambers 14b and 14c that are shielded from each other in parallel are provided, and the printed wiring board 13 in the second and third shield chambers 14b and 14c is provided. High-frequency integrated circuit elements 16 and 17 each incorporating a high-frequency oscillator for receiving BS digital satellite broadcasting are mounted on one side. In this case, the BS digital satellite broadcast signal from the distributor 15 is supplied to the high frequency integrated circuit elements 16 and 17, respectively. The high-frequency integrated circuit elements 16 and 17 constitute, for example, a direct conversion type tuner.

  Subsequent to the second and third shield chambers 14b and 14c, a fourth shield chamber 14d is provided, and a well-known demodulated integrated circuit element is provided on one side of the printed wiring board 13 in the fourth shield chamber 14d. 18 is mounted, and an output signal of the high-frequency integrated circuit element 16 is supplied to the integrated circuit element 18 for demodulation.

  Further, a fifth shield chamber 14e, which is the last shield chamber, is provided following the fourth shield chamber 14d, and a well-known demodulation circuit is provided on one side of the printed wiring board 13 in the fifth shield chamber 14e. The integrated circuit element 19 is mounted, and the output signal of the high frequency integrated circuit element 17 is supplied to the demodulating integrated circuit element 19.

  The circuit configuration of FIG. 3A is as shown in FIG. The circuit configuration shown in FIG. 4 is well known, and detailed description thereof is omitted. In FIG. 4, reference numerals 16a and 17a denote high frequency oscillators.

  In this example, as shown in FIGS. 1 and 5A, the high-frequency integrated circuit elements 16 and 17 that pass from one side to the other side of the printed wiring board 13 corresponding to the mounting portions of the high-frequency integrated circuit elements 16 and 17 are provided. Through holes 20 and 21 having a predetermined size smaller than the shape are formed.

  In this example, a heat radiating sheet 22 made of, for example, a heat radiating silicon rubber sheet is provided through the through holes 20 and 21. In this example, as shown in FIG. 1 and FIG. 5B, the heat radiation sheets 22, 22 are disposed inside the lower case 10 c of the metal shield case 10 at portions corresponding to the heat radiation sheets 22, 22 on the other side of the printed wiring board 13. The heat-dissipating sheets 23 and 23 of a predetermined size made of, for example, heat-dissipating silicon rubber having a thickness in contact with are fixed and adhered.

  In this case, the heat of the high-frequency integrated circuit elements 16 and 17 is conducted to the lower case 10c of the metal shield case 10 through the heat radiating sheets 22 and 22 and the heat radiating sheets 23 and 23 to radiate heat. Other than this, the tuner device is configured in the same manner as in the prior art.

  Since this example is configured as described above, heat radiation sheets 22 and 22 are provided through the through holes 20 and 21 of the printed wiring board 13, and the heat of the high frequency integrated circuit elements 16 and 17 is transferred to the printed wiring board 13. Since the heat radiation sheets 22 and 22 on the other side are conducted to the lower case 10c of the metal shield case 10 through the heat radiation sheets 23 and 23 to dissipate heat, heat can be discharged well.

  Further, according to this example, the heat radiation sheets 22 and 22 are brought into contact with the substrate side of the high frequency integrated circuit elements 16 and 17 where the influence of the high frequency signal is small, and the heat of the high frequency integrated circuit elements 16 and 17 is transferred to the printed wiring board 13. Since the heat radiation sheets 22 and 22 on the other side conduct heat to the lower case 10c of the metal shield case 10 through the heat radiation sheets 23 and 23, the high frequency oscillator inductance of the high frequency integrated circuit elements 16 and 17 becomes the heat radiation sheet. Since there is no inductive coupling or capacitive coupling and no high frequency radiation is received, high frequency characteristics can be maintained satisfactorily.

  Further, even if the high frequency integrated circuit elements 16 and 17 are provided in parallel as in this example, there is no inductive coupling or capacitive coupling, so that there is no inconvenience due to mutual high frequency signal radiation.

  6A and 6B show other examples of the best mode for carrying out the present invention. 6A and 6B, portions corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the above-described example, heat from the heat radiation sheets 22 and 22 on the other side of the printed wiring board 13 from the high frequency integrated circuit elements 16 and 17 is conducted to the lower case 10c of the metal shield case 10 through the heat radiation sheets 23 and 23 to dissipate heat. However, in FIG. 6A, recesses 10d and 10d are formed in the lower case 10c, and the bottoms of the recesses 10d and 10d are brought into contact with the heat radiation sheets 22 and 22, respectively.

  In the example of FIG. 6A, it can be easily understood that the same effect as the above example can be obtained.

  In FIG. 6B, tongue pieces 10e and 10e are provided in the lower case 10c by cutting corresponding to the heat radiation sheets 22 and 22 on the other side of the printed wiring board 13, and the tongue pieces 10e and 10e are provided with the heat radiation sheets 22 and 22 respectively. It is intended to be pressed against.

  It can be easily understood that the effect of the above example can also be obtained in the example of FIG. 6B.

  In the above example, the present invention is applied to a tuner device that receives BS digital satellite broadcasting. However, it is needless to say that the present invention can be applied to a tuner device that receives other broadcasts such as UHF / VHF terrestrial broadcasting.

  In the above example, an example in which two identical tuners are provided has been described. However, different types of tuners may be used, and the number of tuners is not limited to two and may be one or three or more.

  Further, the present invention is not limited to the above-described examples, and various other configurations can be adopted without departing from the gist of the present invention.

It is sectional drawing which shows the example of the best form for implementing this invention tuner apparatus. 1 shows a tuner device according to the present invention, in which A is a top view, B is a bottom view, and C is a side view. It is a top view which shows the example of the principal part of this invention. It is a circuit block diagram of the example of a tuner apparatus. It is a top view which shows the example of the principal part of this invention. It is sectional drawing which shows the other example of the best form for implementing this invention. It is a perspective view which shows the example of the principal part of the conventional tuner apparatus. It is a perspective view which shows the example of the conventional tuner apparatus.

Explanation of symbols

  10 ... Metal shield case, 10a ... Upper case, 10b ... Vent hole, 10c ... Lower case, 10d ... Recess, 10e ... Tongue piece, 11 ... Input terminal, 13 ... Printed wiring board, 14a , 14b, 14c, 14d, 14e... Shield room, 15... Distributor, 16, 17 .. High frequency integrated circuit element, 18, 19 .. Demodulation integrated circuit element, 20, 21. 23 ... Heat dissipation sheet

Claims (2)

A tuner device on which a high-frequency integrated circuit element incorporating a high-frequency oscillator is mounted,
A metal shield case,
A printed wiring board which is fixed in the metal shield case and mounts the high-frequency integrated circuit element on one surface, and is located from the one surface of the printed wiring board at a position where the high-frequency integrated circuit element is mounted. A printed wiring board provided with a through hole provided through the other surface and having a hole area smaller than the mounting area of the high-frequency integrated circuit element;
A heat dissipation sheet that penetrates the through hole and is provided on the other surface of the printed wiring board and is in contact with the metal shield case;
With
Tuner device. A plurality of the high-frequency integrated circuit elements are shielded from each other on the one surface of the printed wiring board .
The tuner device according to claim 1 .

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