WO2002015568A1

WO2002015568A1 - Signal processor and electronic apparatus comprising it

Info

Publication number: WO2002015568A1
Application number: PCT/JP2001/007012
Authority: WO
Inventors: Takeshi Ikeda; Hiroshi Miyagi
Original assignee: Niigata Seimitsu Co., Ltd.
Priority date: 2000-08-14
Filing date: 2001-08-14
Publication date: 2002-02-21
Also published as: TW566038B; JP2002057950A

Abstract

When a tuner section (3) outputting an intermediate frequency signal corresponding to a desired receiving frequency by processing a high frequency signal inputted from a connector (2) specifically and other circuits (4, 5) for processing the intermediate frequency signal outputted from the tuner section (3) are mounted on the same printed circuit board (1), the tuner section (3) is located in the vicinity of the connector (2) and the other circuits (4, 5) are located away from the connector (2). Consequently, an undesired electromagnetic field emitted based on the high frequency signal inputted from a connector (2) is prevented from spreading to the circuits (4, 5) other than the tuner section (3) thus causing noise trouble or oscillation. Since an electromagnetic shield is not required, a plurality of circuits (3-5) can be mounted at high density on one printed circuit board (1).

Description

Description Signal processing device and electronic equipment using the same

The present invention relates to a signal processing device and an electronic device using the same, and is suitable for use, for example, in a receiver that receives television broadcasting and performs predetermined processing. Background art

FIG. 1 is a diagram showing a general configuration of a television receiver for receiving a television broadcast. In FIG. 1, a radio wave for television broadcasting received by an antenna 41 is input to a tuner 42. The tuner 42 generates an intermediate frequency (IF) signal by mixing the high-frequency television signal input from the antenna 41 with a signal of a local oscillation frequency controlled according to a desired reception frequency. I do.

The IF signal extracted by the tuner 42 is amplified by an intermediate frequency amplifier (IF amplifier) 43, and then video-detected by a video detection circuit 44 and audio-detected by an audio detection circuit 45. The signal output from the video detection circuit 44 is separated into a luminance signal and a chrominance signal by a video processing circuit 46, and further subjected to predetermined video signal processing to become a video signal. And the like. The signal output from the sound detection circuit 45 is subjected to processing such as FM demodulation by a sound processing circuit 47 to be a sound signal, and is appropriately amplified and output to a speaker (not shown) or the like.

FIG. 2 is a diagram showing the configuration of the tuner 42. In FIG. The high-frequency television signal for television broadcasting received by the antenna 41 is passed through a band-pass filter (BPF) 51, a high-frequency amplifier (RF amplifier) 52, and a band-pass filter (BPF) 53 to one of the mixers 54. Is input to the input terminal. A local oscillation signal having a local oscillation frequency output from a frequency conversion oscillator (VCO) 55 is input to the other input terminal of the mixer 54. The local oscillation frequency of the signal output from the VC 55 is controlled by a PLL (Phase Locked Loop) circuit 56 in accordance with the set desired reception frequency. The mixer 54 generates an intermediate frequency (IF) signal by mixing the high-frequency television signal output from the BPF 53 and the local oscillation signal output from the VC 555, and generates an intermediate frequency (IF) signal. Output to amplifier 43. The tuner 42 may include an IF amplifier 43.

By the way, in recent years, television receivers are being developed at a rapid pace for miniaturization and thinning. In this context, the integration of tuners has been promoted, and passive elements such as band-pass filters, RF amplifiers, and mixer circuits, which have been realized as external components of semiconductor integrated circuits, have been combined with digital circuits such as PLL circuits. LSIs integrated on a single semiconductor substrate (chip) have also been developed.

However, as described above, although the integration of tuners has been advanced to some extent, the integration of other functional components necessary for constructing a television receiver has been insufficient. For this reason, at present, as described above, a tuner chip integrated on a single semiconductor substrate, a video processing circuit that performs video processing on the output signal, and an audio processing that performs audio processing System processing circuits and the like are modularized and used on one large motherboard.

In a television broadcasting receiver, unnecessary electromagnetic fields may be emitted because high-frequency signals are handled in the tuner section. At this time, released If an unnecessary electromagnetic field is applied to another circuit, the other circuit may be affected by the influence and cause noise disturbance or oscillation. For example, if a video processing circuit or an audio processing circuit receives unnecessary noise of the emitted high-frequency component, the image quality of the television screen may be degraded, or the sound quality of the reproduced sound may be degraded.

Therefore, when the semiconductor chip of the tuner section that handles high-frequency signals and other video processing circuits and audio processing circuits are mounted on the same motherboard, the electromagnetic field that causes noise is generated by the video processing circuit. It is necessary to devise ways to avoid giving it to audio and processing circuits. One way to achieve this is to electromagnetically shield the circuit, such as by forming a wall around a video processing circuit or audio processing circuit using a conductive material. This electromagnetic shielding is usually performed by covering the outer periphery of the target circuit with a metal case. This makes it difficult to mount the semiconductor chip of the tuner section and its peripheral circuits on the same mother board at a high density, and has a problem in reducing the size and thickness of the device. When a video processing circuit and an audio processing circuit are mounted on the same motherboard in addition to the semiconductor chip of the tuner section that handles high-frequency signals, depending on the arrangement of these circuits on the port, the tuner section However, the high-frequency characteristics may be degraded due to the influence on the video processing circuit, the audio processing circuit, etc., or the wiring. In this case as well, the image quality of the TV screen is degraded, and the sound quality of the reproduced sound is also degraded.

The present invention has been made to solve such a problem, and can reduce the circuit scale required for configuring an electronic device such as a television receiver. The purpose is to enable miniaturization and thinning. It is another object of the present invention to suppress deterioration of image quality and sound quality due to mounting a plurality of functional circuit units of an electronic device on the same substrate. Disclosure of the invention

The signal processing device of the present invention is a signal processing device in which a plurality of circuits for processing a signal received by wireless communication are mounted on the same printed circuit board, and the received high-frequency signal is printed on the printed circuit board. A connector to be input into the circuit board; a tuner for outputting an intermediate frequency signal corresponding to a desired reception frequency by performing predetermined processing on a high-frequency signal input from the connector; And a signal processing unit for performing predetermined processing on the intermediate frequency signal output from the control unit. The connector, the tuner unit, and the signal processing unit are mounted on the same printed circuit board. The tuner section is arranged near the connector.

In another aspect of the present invention, the signal processing unit is disposed on the opposite side of the tuner unit from the connector.

In another aspect of the present invention, the signal processing unit includes a circuit that generates a video signal by performing a predetermined process on the video.

Alternatively, the signal processing unit includes a circuit that generates a sound signal by performing predetermined processing related to sound.

Alternatively, the signal processing unit includes a circuit that generates a video signal by performing predetermined processing related to video and a circuit that generates an audio signal by performing predetermined processing related to audio.

In another aspect of the present invention, the high-frequency signal received by the wireless communication is a television broadcast signal.

Further, the electronic device of the present invention may be arranged such that the received high-frequency signal A connector to be input into the board; a tuner section that performs an predetermined process on a high-frequency signal input from the connector to output an intermediate frequency signal corresponding to a desired reception frequency; and a tuner section that outputs the tuner section. A signal processing unit for performing predetermined processing on the intermediate frequency signal is mounted on the same printed circuit board, and the connector is fixed to a predetermined position of the housing, thereby mounting the printed circuit board on the printed circuit board. It is designed to be mounted on a housing.

In another aspect of the present invention, the tuner section is arranged near the connector.

Since the present invention comprises the above technical means, the signal processing unit in addition to the tuner unit is integrated on the same semiconductor substrate, and the semiconductor substrate is integrated with the connector, so that the television receiver and the like are integrated. This makes it possible to further reduce the circuit scale required to configure the electronic device. Further, according to the present invention, unnecessary electromagnetic fields emitted based on the high-frequency signal input from the connector are less likely to be given to the circuit that handles the intermediate frequency signal other than the tuner section, and the noise interference due to the electromagnetic field is reduced. And inconvenience of causing oscillation can be suppressed. Therefore, it is not necessary to provide an electromagnetic shield around the video processing circuit or the audio processing circuit, or around the tuner.

As a result, various circuits that handle high-frequency signals and intermediate-frequency signals can be mounted on a single printed circuit board with high density, further reducing the size and thickness of electronic devices such as television receivers. Can be realized. In addition, deterioration of image quality and sound quality can be suppressed by reducing the influence of unnecessary electromagnetic waves and deterioration of high-frequency characteristics.

In addition, by disposing a tuner for handling high-frequency signals input from the connector near the connector, etc. There is no need to arrange a video processing circuit or an audio processing circuit, etc., and the wiring between the connector and the tuner can be shortened. This makes it possible to suppress the inconvenience of deteriorating high-frequency characteristics due to the influence on the video processing circuit, audio processing circuit, or wiring.

Further, according to the electronic apparatus of the present invention, the connector, the tuner section, and the signal processing section are mounted on the same printed circuit board at a high density, and the printed circuit board itself forms the housing. The tuner and the signal processing unit are arranged on a mother board with connectors, and the mother pod is mounted on the housing. This eliminates the need for mounting, and eliminates the need for a large motherboard. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram illustrating a general configuration example of a conventional television receiver. FIG. 2 is a diagram illustrating a configuration example of a tuner.

FIG. 3 is a diagram illustrating a configuration example of a signal processing device of a television receiver according to the present embodiment.

FIG. 4 is a diagram showing a state in which the signal processing device (printed circuit board) configured as shown in FIG. 3 is attached to a housing of a television receiver. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a diagram illustrating a configuration example of a signal processing device of a television receiver according to the present embodiment. As shown in FIG. 3, the signal processing device of the television receiver according to the present embodiment receives and processes a television broadcast. It is configured by mounting multiple functional circuits required for a single printed circuit board (PCB) 1.

In the present embodiment, a connector 2, a tuner unit 3, a video processing circuit 4, and an audio processing circuit 5 are mounted on the printed circuit board 1. The connector 2 is for inputting a radio wave (high-frequency television signal) for television broadcasting received by a receiving antenna (not shown), and is fixed to a housing of the television receiver as an external terminal of the television receiver. You.

The tuner unit 3 has almost the same function as the tuner 42 and the IF amplifier 43 shown in FIG. That is, by mixing the high-frequency television signal received by the receiving antenna (not shown) and input via the connector 2 with the signal of the local oscillation frequency controlled according to the set desired receiving frequency, the intermediate frequency Extract the (IF) signal. Then, the extracted IF signal is amplified.

The video processing circuit 4 performs predetermined video processing on the IF signal output from the tuner unit 3 and generates a video signal that can be displayed on a display device such as a CRT or LCD (not shown). is there. For example, the video signal is generated by performing demodulation processing on the IF signal output from the tuner unit 3 and then performing predetermined video signal processing by separating the signal into a luminance signal and a color signal. The generated video signal is output from a video output terminal 6 to a display device such as a CRT or LCD not shown.

The audio processing circuit 5 performs a predetermined process related to audio on the IF signal output from the tuner unit 3, and generates an audio signal that can be output to a speaker (not shown). For example, after performing a demodulation process on the IF signal output from the tuner unit 3, the audio signal is generated by performing a predetermined audio signal process such as volume adjustment and amplification. The generated audio signal is output from an audio output terminal 7 to a speaker (not shown). In the signal processing device of the television receiver configured as shown in FIG. 3 above, at least the tuner unit 3 includes passive elements such as a band-pass filter, an RF amplifier, and a mixer circuit together with a PLL circuit on a single semiconductor substrate. It is configured as a semiconductor chip. Also, the video processing circuit 4 and the audio processing circuit 5 can be configured as semiconductor chips integrated on one semiconductor substrate, respectively.

In the present embodiment, as a method of arranging the tuner section 3, the video processing circuit 4, and the audio processing circuit 5 on the printed circuit board 1, the tuner section 3 for handling a high-frequency signal input from the connector 2 is used. A circuit that handles the intermediate frequency signal other than the tuner unit 3 is arranged near the connector 2 and is located downstream of the tuner unit 3 and separated from the connector 2. That is, they are arranged on the printed circuit board 1 in the order of the connector 2, the tuner section 3, and other circuits.

By arranging in this way, unnecessary electromagnetic fields emitted based on the high-frequency signal input from the connector 2 are less likely to be given to circuits other than the tuner section 3 that handle intermediate frequency signals, and the influence of the electromagnetic field is reduced. As a result, inconveniences such as noise disturbance and oscillation can be suppressed. Therefore, it is not necessary to provide an electromagnetic shield around the video processing circuit 4 and the audio processing circuit 5 or around the tuner section 3, and various functional circuits for handling high-frequency signals and intermediate frequency signals are provided. It can be mounted on the printed circuit board 1 with high density.

In addition, by disposing a tuner section 3 for handling a high-frequency signal input from the connector 2 near the connector 2, a video processing circuit 4, an audio processing circuit 5, and the like are provided between the connector 2 and the tuner section 3. And the wiring between the connector 2 and the tuner 3 can be shortened. As a result, there is an influence on the video processing circuit 4, the audio processing circuit 5, or the wiring. In addition, the disadvantage that the high-frequency characteristics are deteriorated can be suppressed.

FIG. 4 is a diagram showing a state in which the signal processing device (printed circuit board 1) configured as shown in FIG. 3 is attached to a casing of a television receiver. As shown in FIG. 4, in the printed circuit board 1 of the present embodiment, the connector 2 is fixed to a predetermined position of the housing 10 using a fixing member 11 such as a port and a nut. At this time, the printed circuit board 1 is attached to the housing 10 by fixing at least a part of the connector 2 so as to protrude outside the housing 10.

As described above, in the present embodiment, the connector 2 is mounted on the same printed circuit board 1 together with the tuner unit 3, the video processing circuit 4, and the audio processing circuit 5, so that each circuit is connected to the connector 2. Integrated, for example, with the printed circuit board 1 floating in the housing. In this way, the tuner 3, the video processing circuit 4, and the audio processing circuit 5 need not be arranged on a mother board with connectors, and the mother board does not need to be attached to the housing. One port can be eliminated.

As described above, according to the present embodiment, a plurality of functional circuits can be mounted on the printed circuit board 1 at a high density, so that the television receiver can be further reduced in size and thickness. At the same time, deterioration of image quality and sound quality can be suppressed by reducing the influence of unnecessary electromagnetic waves and deterioration of high frequency characteristics. In the above embodiment, the case where the tuner unit 3, the video processing circuit 4, and the audio processing circuit 5 are mounted on one printed circuit board 1 has been described, but the present invention is not limited to this. Absent. For example, when the tuner section 3 and the video processing circuit 4 are mounted on one print circuit board 1, or the tuner section 3 and the audio processing circuit 5 are mounted on one print circuit board 1. The same can be applied to the case where the above is performed. Circuits other than the video processing circuit 4 and the audio processing circuit 5 are connected to the tuner section. The same can be applied to the case of mounting on a single printed circuit board 1 together with 3. For example, a microcomputer that controls the operations of the tuner section 3, the video processing circuit 4, and the audio processing circuit 5, and a flash memory and a RAM that are used when receiving and processing digital broadcast waves are the same. It can also be mounted on the small printed circuit board 1. In this case, similarly, by arranging the tuner section 3 near the connector 2 and arranging other circuits away from the connector 2, the same effect as described above can be obtained.

Further, in the above-described embodiment, the connector 2 is mounted on the printed circuit board 1, and a high-frequency signal received by an antenna (not shown) is input into the printed circuit board 1 via the connector 2. The antenna itself may be mounted on the printed circuit board 1 instead of the connector 2. In this case, the tuner 3 is arranged near the antenna, and the other video processing circuit 4 and audio processing circuit 5 are arranged on the opposite side of the antenna with the tuner 3 interposed therebetween.

In the above embodiment, the case where the signal processing device of the present invention is applied to a television receiver has been described. However, the present invention is not limited to this, and at least a video signal or an audio signal can be obtained by wireless communication. The same can be applied to any device that receives one of them and performs predetermined processing and outputs it. For example, the present invention can be applied to a wireless communication terminal such as a mobile phone or a PHS having an RF filter or the like, a radio receiver for an AM broadcast, an FM broadcast, a short wave broadcast, or the like.

In addition, the above-described embodiments are merely examples of embodying the present invention, and the technical scope of the present invention should not be limitedly interpreted. is there. That is, the present invention may be embodied in various forms without departing from its spirit or its main features. be able to. Industrial applicability

INDUSTRIAL APPLICABILITY The present invention makes it possible to further reduce the circuit scale required for configuring an electronic device such as a television receiver, and is useful for further reducing the size and thickness of the electronic device.

Further, the present invention is also useful for suppressing deterioration of image quality and sound quality due to mounting a plurality of functional circuit units of an electronic device on the same substrate.

Claims

The scope of the claims

1. A signal processing device in which a plurality of circuits for processing a signal received by wireless communication are mounted on the same printed circuit board,

A connector for inputting the received high-frequency signal into the printed circuit board; and a tuner section for performing a predetermined process on the high-frequency signal input from the connector to output an intermediate frequency signal corresponding to a desired reception frequency. ,

A signal processing unit for performing predetermined processing on the intermediate frequency signal output from the tuner unit,

A signal processing device, wherein the connector, the tuner unit, and the signal processing unit are mounted on the same printed circuit board, and the tuner unit is disposed near the connector.

2. The signal processing device according to claim 1, wherein the signal processing unit is arranged on a side opposite to the connector with the tuner unit interposed therebetween.

3. The signal processing device according to claim 1, wherein the signal processing unit includes a circuit that generates a video signal by performing a predetermined process on a video.

4. The signal processing device according to claim 1, wherein the signal processing unit consumes a circuit that generates a voice signal by performing a predetermined process on voice.

5. The signal processing unit includes a circuit that generates a video signal by performing predetermined processing related to video, and a circuit that generates an audio signal by performing predetermined processing related to audio. The signal processing device according to claim 1.

6. The signal processing device according to claim 1, wherein the high-frequency signal received by the wireless communication is a television broadcast signal.

7. A connector for inputting the received high-frequency signal into the printed circuit board, and a tuner section for performing a predetermined process on the high-frequency signal input from the connector to output an intermediate frequency signal corresponding to a desired reception frequency. And a signal processing unit for performing predetermined processing on the intermediate frequency signal output from the tuner unit are mounted on the same printed circuit board, and the connector is fixed at a predetermined position of the housing. An electronic device, wherein the printed circuit board is attached to the housing.

8. The electronic device according to claim 7, wherein the tuner is disposed near the connector.