JP3110604B2 - Card type electronic tuner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a card type electronic tuner.

[0002]

2. Description of the Related Art A conventional card-type electronic tuner will be described below.

A conventional card-type electronic tuner includes a signal input terminal, a mixer in which a signal from the signal input terminal is supplied to one input and an output of a local oscillator is supplied to the other input. A demodulator to which the output of the demodulator is supplied, an output terminal to which the output of the demodulator is supplied, and a PLL circuit connected to the data input terminal and controlling the oscillation frequency of the local oscillator are provided in a card type case. The signal input terminal, the output terminal, and the data input terminal are both provided on one lateral side of the case. Therefore, following the signal input terminal on one lateral side of the case, a mixer and the like are arranged,
Since the demodulator connected to the output terminal is arranged near the output terminal, the local oscillator and the PLL circuit are mounted at a position apart from one side surface of the case. .

As a technique similar to this, there is, for example, JP-A-5-14133.

[0005]

However, in the above-mentioned conventional configuration, since the PLL circuit is located far from the data input terminal, the tuning data line is connected to the PL from the data input terminal.
The circuit has to be extended to the L circuit, the circuit arrangement is inefficient, and noises are picked up on the selected data line, so that there is a problem that a malfunction is likely to occur.

An object of the present invention is to solve the above-mentioned conventional problems and to realize a card-type electronic tuner with improved malfunction.

[0007]

In order to achieve this object, a card-type electronic tuner according to the present invention has a data input terminal in the vicinity of a PLL circuit, and has an output terminal, a power supply input terminal, and a data input terminal. The signal input terminal is provided on one lateral side of the case, and the signal input terminal is located on the vertical side and near the lateral side.
A set book that will be installed next to this case
The television signal from the side of the body to the signal input terminal
It is configured to be directly introduced into the system.

[0008]

[Action] More this configuration, since provided a PLL circuit in the vicinity of the data input terminal, P channel selection data lines at a short distance
Can be connected to LL circuit. Therefore, there is no need to route digital selection data lines inside the card .
Since there is little possibility that the noise due to the digital signal is applied to other circuits in the case, the malfunction can be improved.

[0009]

An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 are plan views of a card-type electronic tuner according to an embodiment of the present invention, and FIG. 3 is a block diagram thereof.

Hereinafter, a card-type electronic tuner according to the present invention will be described with reference to FIGS. 1, 2 and 3. First, referring to FIGS. 1 and 3, the electronic tuner of the present invention has a signal input terminal 1.
And a mixer 3 in which the signal of the signal input terminal 1 is supplied to one input and the output of the local oscillator 2 is supplied to the other input, and a demodulator 4 to which the output of the mixer 3 is supplied. An A / D converter 8 to which the output of the demodulator 4 is supplied; an output terminal 5 to which the output of the A / D converter 8 is supplied; and a local oscillator connected to the data input terminal 7. 2 and a DC-DC converter 9 connected to a power input terminal 14 and supplying a tuning voltage to the PLL circuit 6 are housed in a card-type case 13 shown in FIG. The output terminal 5, the data input terminal 7, and the power input terminal 14 are provided on one side surface 15 of the case 13, and the signal input terminal 1 is provided on the side surface 15 (FIG. 1) of the case 13.
Alternatively, it is provided on the vertical side surface 16 (FIG. 2) near the horizontal side surface 15.

Thus, the set body 20 (FIG. 4)
When the card 13 is inserted with one lateral side 15 facing forward, in the embodiment of FIG. 1, a high-frequency signal is directly transmitted from a dedicated connector provided for the card-type electronic tuner such as a video camera. It can be introduced to the signal input terminal 1.

Further, in the embodiment shown in FIG. 2, it is not necessary to modify the set body 20 for a connector provided for general use such as a personal computer, for example, and as shown in FIG. A high-frequency signal can be introduced into the signal input terminal 1 from the side.

The internal antennas 10,
Subsequently, the tuner unit 12 including the mixer 3 and the local oscillator 2
Is provided, adjacent to the tuner section 12,
PLL circuit 6 between the side surface 15 and the data input terminal 7 side
There is a compartment. D near the power input terminal 14
A C-DC converter 9 is mounted.

Further, a compartment for the demodulator 4 is provided between the tuner section 12, the output terminal 5 side of the lateral side surface 15 and the other vertical side surface 17 side, and the A / D conversion is performed near the output terminal 5. Vessel 8 is arranged.

Note that an audio multiplexing circuit may be provided between the demodulator 4 and the output terminal 5, and the audio multiplexing circuit may be arranged near the output terminal 5. This is for enjoying a stereo broadcast.

Here, as the antenna input, the signal input terminal 1 is provided on the lateral side surface 15 or on the vertical side surface 16 near the lateral side surface 15. Then, the internal antenna 10 is mounted in the case 13, the internal antenna 10 is connected to the signal input terminal 1, and the antenna 10 is provided near the signal input terminal 1. If the antenna 10 is housed in the case 13 in this way, reception becomes possible without an external antenna.

Here, the tuner unit 12 is separated from the PLL circuit 6 and the demodulation unit 4 by a metal partition plate. PL
The L circuit 6 is provided adjacent to the data input terminal 7 so that a digital signal such as a clock does not affect the tuner 12.

Further, a demodulator 4 is provided near the output terminal 5 and an A / D is provided between the demodulator 4 and the output terminal 5.
A D converter 8 is connected, and the A / D converter 8 is arranged between the demodulator 4 and the output terminal 5.

As for the power supply, in order to use a single power supply,
The DC-DC converter 9 is used to connect the DC-DC converter 9 to the power input terminal 14 and
The output of the C-DC converter 9 is connected to a tuning voltage generation circuit of the PLL circuit 6 to obtain a tuning voltage to be supplied to the local oscillator 2. In addition, the power input from the power input terminal 14 is converted into a required voltage and supplied to the mixer 3, the local oscillator 2, the demodulator 4, the A / D converter 8, and the like.

Next, the implementation of the antenna will be described. First, a bar antenna may be used, which may be arranged substantially parallel to the vertical side surface 16 of the case 13.

Next, a rod antenna 11 may be used and provided outside the case 13 on the side of the longitudinal side 16 and attached to the signal input terminal.

Of course, an antenna cable 21 may be inserted instead of the rod antenna 11. FIG. 4 is a plan view of a main part using such a method.

The operation of the card-type electronic tuner configured as described above will be described below.

Television video and audio signals inputted from the signal input terminal 1 by the internal antenna 10 or the external rod antenna 11 are transmitted to a desired channel by a tuner 12 comprising a mixer 3 and a local oscillator 2. Tuned. Next, the video signal is demodulated by the demodulator 4, and the demodulated video signal is YC-separated by the A / D converter 8 and becomes RGB output, which can be directly output to the set main body screen. The audio signal can be directly output from the main body speaker.

As described above, according to the embodiment shown in FIG.
Insert the card-type electronic tuner of the present invention into a set body such as a personal computer or video camera,
Television images and audio can be received.
Further, according to the embodiment shown in FIG. 2, the signal can be received without providing the signal input terminal 1 as a special terminal on the set body side.

The antenna 10 is connected to the signal input terminal 1 and provided near the signal input terminal 1.
It is stored in the case 13. Therefore, in a strong electric field area, it is possible to receive television video and audio and AM radio broadcast without the trouble of separately using an external antenna. The antenna 10 is connected to a card 13
Because it is stored inside, the antenna can be easily protected when not in use.

Since the tuner section 12 is disposed near the signal input terminal 1, the attenuation of the input level of the television signal supplied from the signal input terminal 1 can be suppressed as much as possible. Further, it is possible to suppress a signal other than a desired channel at the time of reception from interfering with other circuits such as the demodulator 4.

If the antenna 10 is constituted by a bar antenna integrated substantially in parallel with the vertical side surface 16 of the card 13, it can receive AM radio broadcasting without using an external antenna and supplies a highly sensitive signal to the mixer 3. be able to.

As shown in FIG. 2, if an external rod antenna 11 is used outside the card 13 as an antenna, television video and audio can be received, and a highly sensitive television signal can be supplied to the mixer 3. Can be.

If the rod antenna 11 is detachable, the antenna can be easily protected when not in use.

Since the PLL circuit 6 is provided adjacent to the data input terminal 7, radiation of control signals such as a clock signal, a data signal, and an enable signal from the data input terminal 7 can be minimized. Further, it is possible to suppress interference from another oscillation circuit to the control signal line.

Since the demodulator 4 is provided in the vicinity of the output terminal 5, it is possible to minimize the interference of the demodulated video and audio signals such as harmonics of other circuits such as the oscillation circuit 2.

Since the A / D converter 8 is provided between the demodulator 4 and the output terminal 5 in the card 13, the television picture can be provided without disposing the A / D converter 8 on the set body. Can be output directly to the display of the set body. Therefore, it is not necessary to provide the A / D converter 8 in the set main body, and the burden on the set main body can be reduced. Further, since the demodulated video signal is far from the oscillation circuit 2, interference such as harmonics can be suppressed as much as possible.
Further, since the A / D converter 8 and the output terminal 5 are provided adjacent to each other, it is possible to minimize disturbance of harmonics and the like from other circuits such as the oscillation circuit 2 to the signal after the A / D conversion. Can be.

Finally, the DC-DC converter 9 is connected to the power supply input terminal 14 and the output of the DC-DC converter 9 is connected to the PLL circuit 6 provided in the vicinity. The DC power supply (30 volts) can suppress a disturbance of noise from other circuits and can supply a stable power supply. Further, since the DC-DC converter 9 is built in, there is no need to provide the DC-DC converter 9 on the set main body side, and the burden on the set main body side can be reduced.

[0036]

As described above, according to the card-type electronic tuner of the present invention, the data input terminal is provided near the PLL circuit, and the output terminal, the power input terminal, and the data input terminal are connected to one lateral side of the case. And the signal input terminal is on the vertical side.
On the side and near the lateral side,
From the side of the set body into which the base is inserted.
Signal is directly introduced into the signal input terminal, so that the PLL
The circuit is provided near the data input terminal, and can connect the selected data line to the PLL circuit over a short distance. Therefore,
The tuning data line, which is a digital signal, is not routed inside the card, and noise due to the digital signal is less likely to get on other circuits in the case, so that malfunction can be improved. Also, since a PLL circuit is provided close to the 30 volt output of the DC-DC converter,
The possibility that noise enters the tuning voltage in the L circuit is small. Further, since the television signal is introduced directly from the side of the set, no special electrical changes need to be made on the set side.

[Brief description of the drawings]

FIG. 1 is a plan view of a card-type electronic tuner according to an embodiment of the present invention.

FIG. 2 is a plan view of a card-type electronic tuner according to another embodiment of the present invention.

FIG. 3 is a block diagram of a card-type electronic tuner according to an embodiment of the present invention.

FIG. 4 is a plan view of a card-type electronic tuner when inserted into a set according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Signal input terminal 2 Local oscillator 3 Mixer 4 Demodulator 5 Output terminal 6 PLL circuit 7 Data input terminal 13 Case

Continuation of the front page (56) References JP-A-5-14133 (JP, A) JP-A-5-22163 (JP, A) JP-A-5-136655 (JP, A) JP-A-61-150410 (JP) JP-A-4-295886 (JP, A) JP-A-4-47732 (JP, U) JP-A-5-501032 (JP, A)

Claims (1)

(57) [Claims] 1. A signal input terminal to which a television signal is input, a mixer to which a signal of the signal input terminal is supplied to one input and an output of a local oscillator is supplied to the other input, A demodulator to which the output of the mixer is supplied, an analog / digital converter (hereinafter, referred to as an A / D converter) to which the output of the demodulator is supplied, an output of the A / D converter,
An output terminal provided near the / D converter, a power input terminal to which a DC voltage is input, and a DC voltage of approximately 30 volts connected to the power input terminal to output a single power supply. Voltage boost converter (hereinafter, referred to as a DC / DC converter) provided between the DC / DC converter and a PL provided near the output of the DC / DC converter.
The L circuit is housed in a card type case, a data input terminal is provided near the PLL circuit, and the output terminal, the power supply input terminal, and the data input terminal are provided on one lateral side of the case, The signal input terminal is located on the vertical side.
And in the vicinity of the side surface, and this case
The television signal from the side of the set body
A card-type electronic tuner directly introduced into the signal input terminal .