JPH087702Y2 - Television receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a television receiver, and more particularly to a television receiver suitable for a channel selection system using a frequency synthesizer.

(Prior Art) Conventionally, in television receivers, video tape recorders, and the like, there is a strong demand for miniaturization of tuners.
Also, high-definition television receivers such as EDTV and HDTV systems have been developed, and a compact, high-definition and high-performance tuner is required. For this reason, the tuner and its peripheral circuits are combined to reduce the routing of wiring and to reduce the size and performance of the interface by reducing the number of interface components.

That is, in the past, the tuner and its peripheral circuit, the PLL
The (Phase Locked Loop) IC (for frequency synthesizer tuning) was configured on the main board of the device, and the local oscillation output of the local oscillation circuit of the tuner was applied to the PLL IC using a coaxial cable or feedthrough capacitor. . On the other hand, in the integrated structure shown in FIG. 2, the metal shield case 1
The tuner unit 2 and the PLL unit 3 are arranged adjacent to each other.
A local oscillation circuit 4 is formed at the end of the tuner unit 2 on the PLL unit 3 side, and the local oscillation output is given to a PLL IC 5 in the PLL unit 3. By making the tuner section 2 and the PLL section 3 into an integrated structure, it is possible to reduce the number of coaxial cables, feedthrough capacitors, etc., and save space, improve performance, and reduce wiring layout.

FIG. 3 is an explanatory diagram showing an integrated structure of a tuner section and an intermediate frequency amplification section (hereinafter referred to as an IF section) adopted in the voltage synthesizer channel selection system.

In the metal shield case 6, the tuner section 2 and the IF section 7 are arranged adjacent to each other. The tuner unit 2 includes a local oscillator circuit 4 and a high frequency amplifier circuit 8, and an IF unit 7 has an IF
An IC A9 includes an IF AGC circuit and an IF AFT circuit, which are not shown. The output of the IF AFT circuit is given to the local oscillator circuit 4, and the output of the IF AGC circuit is given to the high frequency amplifier circuit 8. In this way, the metal shield case 6 has an integrated structure.
By making the connection inside, the feed-through capacitor of the interface component is not necessary, and the routing of the wiring can be reduced to achieve downsizing and high performance.

By the way, recently, the channel selection system has been shifting from the voltage synthesizer system to the frequency synthesizer system because of its high reliability and no need for channel adjustment at the time of installation. In the frequency synthesizer system, if the tuner part, the IF part, and the PLL part are to be integrated,
The structure shown in FIG. 4 is conceivable. That is, in the metal shield case 10, the tuner section 2, the PLL section 3 and the IF section 7 are provided.
Are arranged side by side in a row.

However, in this arrangement, the PLL unit 3 and the tuner unit 2 and I
It bisects F part 7. Therefore, the tuner unit 2
Interface parts are required to connect the interface with the IF section 7. There was a problem that there were few advantages due to the integrated structure.

(Problems to be solved by the invention) As described above, in the conventional television receiver in which the tuner section, the PLL section, and the IF section are integrated, the PLL section bisects the tuner section and the IF section. However, there was a problem that there were few advantages of integration.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a television receiver that can be downsized and have high performance by having an integrated structure that follows the flow of signals. And

[Configuration of the Invention] (Means for Solving the Problems) A television receiver according to the present invention is a tuner having a high frequency signal processing means and an intermediate frequency converting means, as shown in the basic configuration diagram of FIG. A television receiver having a section, an intermediate frequency amplification section for processing an intermediate frequency signal from the tuner section, and a PLL section for controlling the local oscillation frequency section of the tuner section, the television receiver facing each other. A shield case formed in a frame shape having a first and a second surface, and third and fourth surfaces connecting between both ends of the first and second surfaces; A high frequency signal input terminal provided on the first surface and a first part of the shield case surrounded by the first, third and fourth surfaces, and connected to the high frequency signal input terminal And the edge portion on the side opposite to the input terminal is Of the tuner portion extending toward the surface of the tuner and the remaining portion of the shield case surrounded by the second, third, and fourth surfaces from the third surface to the end edge of the tuner portion. Section, and an intermediate frequency amplification section arranged in one of the two sections, a PLL section arranged in the other section obtained by dividing the remaining section in two, the tuner section, and the intermediate frequency section. In order to connect the amplification section and the PLL section to the external circuit, the third part of the shield case is connected.
A plurality of terminals arranged on the surface of, a wiring member for directly connecting between the tuner unit and the intermediate frequency amplification unit, and between the tuner unit and the PLL unit in the shield case. The tuner section, the intermediate frequency amplification section, and the PLL section are integrally formed in the shield case, and the tuner section and the intermediate frequency amplification section, and the tuner section and the PLL section are connected by short wiring. It is characterized by.

(Operation) In the present invention, one surface of the tuner section is adjacent to one surface of the intermediate frequency amplification section and the PLL section. Therefore, the wiring connecting the tuner unit and the intermediate frequency amplification unit and the wiring connecting the tuner unit and the PLL unit can form the shortest signal path, and no interface component is required. Also, the tuner section,
The intermediate frequency amplification unit and the PLL unit are arranged adjacent to the main substrate connecting surface of the shield case, and wiring arrangements such as supply of power supply voltage from the main substrate are also reduced.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory view showing an embodiment of a tuner of a television receiver according to the present invention and its peripheral circuits.

Tuner 2 and PLL 12 in the metal shield case 11.
And the IF unit 13 are configured. The tuner portion 2 occupies from one end of the metal shield case 11 to a substantially central portion thereof, and the antenna terminal 14 is disposed at the end so as to project from the metal shield case 11. Tuner unit 2 is VHF
And a high frequency amplifier circuit 8 for UHF, a local oscillator circuit 4, a mixer (not shown) and an IF output circuit 15,
The RF input signal from the antenna terminal 14 is converted into an IF signal.
The high frequency amplifier circuit 8 is arranged in the vicinity of the antenna terminal 14, and the local oscillation circuit 4 and the IF output circuit 15 are arranged on the center side of the metal shield case 11 of the tuner unit 2.

One surface of the PLL section 12 and the IF section 13 is adjacent to one surface of the tuner section 2 on the center side of the metal shield case 11. That is, the PLL section 12 and the IF section 13 occupy about half of the other end of the metal shield case 11 from the substantially central portion,
The PLL unit 12 has an L shape, and the IF unit 13 is arranged so as to be surrounded by the PLL unit 12, the tuner unit 2, and the metal shield case 11. The PLL IC 5 is configured in the PLL unit 12, and the local oscillation frequency is directly controlled to perform tuning by the frequency synthesizer method. IF in IF section 13
The IC9 is configured to amplify and detect the IF signal and to amplify and detect the audio intermediate frequency signal.

One surface of the tuner section 2, the PLL section 12, and the IF section 13 faces the main board connecting surface 16 of the metal shield case 11, and the connection with the main board 17 of the main body of the apparatus can reduce the wiring. It's easy. The main board 17 has a power supply terminal 18 for supplying a power supply voltage to the tuner section 2, a power supply terminal 19 for supplying a power supply voltage to the PLL section 12, and a lock to the PLL section 12,
Control terminal that supplies control voltage such as data and enable
20, power supply terminal 21 for applying power supply voltage to IF section 13, IF section
A control terminal 22, a video terminal 23, and an audio terminal 24 for supplying a control voltage such as an audio mute to the 13 are provided.

In the embodiment thus configured, the local oscillation output from the local oscillation circuit 4 is given to the PLL IC 5 and the PLL
In order to apply the tuning voltage from IC5 to the local oscillator circuit 4,
Connections are made in the metal shield case 11 by patterns or jumper wires 25 or the like. Also, from the IF output circuit 15
In order to apply the IF signal to the IF IC9 and the IF AGC voltage from the IF IC9 to the high frequency amplifier circuit 8, connection is made in the metal shield case 11 by a pattern or a jumper wire 26 or the like. In addition, the tuner unit 2, the PLL unit 12, and the IF unit 13
On the main board connecting surface 16 of the metal shield case 11, each power supply terminal 18, 19, 21 of the main board 17 and each control terminal 2
0, 22, a video terminal 23 and an audio terminal 24 are connected.

As described above, in this embodiment, the PLL unit 12 is formed in the L-shape so that one surface of the tuner unit 2 and the PLL unit 1 are
The tuner section 2 and the PLL section 12 and the tuner section 2 and the IF section 13 can be connected to each other without interposing the main board 17 so that the tuner section 2 and the IF section 13 face each other. Since one surface of the PLL section 12 and the IF section 13 is arranged so as to face the main board connecting surface 16 of the metal shield case 11, the connection with the main board 17 is easy and the routing of wiring can be reduced. You can With an integrated structure,
By obtaining the shortest signal path and reducing the routing of wiring, it is possible to reduce the size and improve the performance. In addition, the number of interface parts can be reduced and the structure is inexpensive.

[Advantages of the Invention] As described above, according to the present invention, the shortest signal path is configured to reduce the routing of wiring, and it is possible to achieve miniaturization and high performance.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a tuner of a television receiver and its peripheral circuit according to the present invention, and FIGS. 2 to 4
FIG. 1 is an explanatory diagram showing a tuner of a conventional television receiver and its peripheral circuits, and FIG. 5 is a basic configuration diagram of the present invention. 2 ... Tuner part, 11 ... Metal shield case, 12 ... PLL
Section, 13 ... IF section, 16 ... Main board connecting surface, 17 ... Main board.

Claims (1)

[Scope of utility model registration request] 1. A tuner unit having a high frequency signal processing unit and an intermediate frequency converting unit, an intermediate frequency amplifier unit for processing an intermediate frequency signal from the tuner unit, and a local oscillation frequency unit of the tuner unit. A television receiver having a PLL section for connecting the first and second surfaces facing each other, and the third and fourth surfaces connecting between both ends of the first and second surfaces. A frame-shaped shield case, a high-frequency signal input terminal provided on the first surface of the shield case, and the first, third, and fourth surfaces in the shield case. A tuner portion that is disposed in the enclosed first portion and that is connected to the high-frequency signal input terminal, and that has an end edge opposite to the input terminal that extends toward the second surface side; , The remaining part surrounded by the second, third and fourth surfaces An intermediate frequency amplifying section that is bisected from the third surface toward the edge portion of the tuner section and that is disposed in one of the two sections, and the other section that is bisected in the remaining section. PLL located at
Section, the tuner section, the intermediate frequency amplifier section, and the PLL section, and a plurality of terminals arranged on the third surface of the shield case for connecting the external circuit, the tuner section, and the intermediate frequency section. A wiring member that directly connects between the amplification units and between the tuner unit and the PLL unit in the shield case, wherein the tuner unit, the intermediate frequency amplification unit, and the PLL unit are provided in the shield case. A television receiver in which the tuner section and the intermediate frequency amplifier section, and the tuner section and the PLL section are connected by a short wiring.