JP2008199238A - Signal processing device, and signal playback device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To speedily select a desired input system in a signal playback device which has a plurality of input systems and switches the input systems in a sequential switching manner. <P>SOLUTION: The signal playback device is provided with a rectifier 31a having a diode 33 and a capacitor 34 between an A/D converter 16a and a controller 14. The anode of the diode 33 is connected to an output terminal of the A/D converter 16a. One end of the capacitor 34 and the controller 14 are connected to the cathode of the diode 33, and the other end of the capacitor 34 is grounded, where the rectifier 31a is composed of the diode 33 and capacitor 34. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a signal processing apparatus and a signal reproduction apparatus that include a plurality of signal input terminals and that can be switched sequentially.

  A signal reproducing device such as a CRT (Cathode Ray Tube) or a liquid crystal display device or a television equipped with such a signal reproducing device is provided with a plurality of audio / video signal input terminals, such as a video deck or a DVD player. Some AV (Audio Visual) devices can be connected. In such a display device or the like, a changeover switch such as a button for selecting a desired terminal or display is provided on the main body or the remote control, and a user selects and outputs an input from the desired terminal. Become.

  As the selection method, for example, the applicant of the present application has proposed a method using a screen display of OSD (On Screen Display) (Patent Document 1). In this method, the terminal and the connection status of the device to the terminal are displayed on the screen as the OSD, and it becomes easy to select a desired terminal.

  Patent Document 1 proposes a method of displaying a terminal and the connection status of the device to the terminal on an screen as an OSD (On Screen Display), and facilitating selection of a desired terminal.

  However, even if the method of Patent Document 1 is used, when the change-over switch is of a sequentially switchable type, it is unlikely to be selected like a terminal to which no device is connected or a terminal to which no signal is input. Switching is possible including terminals. For this reason, the number of times the changeover switch is pressed increases until a terminal to which a device for reproducing desired images and sounds is connected is selected. Therefore, a method of skipping a terminal to which no device is connected (Patent Document 2) and a method of skipping a terminal to which no video signal is input (Patent Document 3) have been proposed.

Furthermore, even if a device is connected, a terminal that does not receive a signal from the device because it is not turned on is unlikely to be selected. A method has been proposed in which a terminal to which no video signal is input is skipped at the time of switching by detecting a synchronized signal.
JP 2006-03356 A Japanese Patent Laid-Open No. 10-262190 Japanese Patent Laid-Open No. 5-207386

  However, in the method proposed in Patent Document 3, the synchronization signal must be detected from the video signal, and a special circuit needs to be provided.

  Therefore, the present invention provides a sequential switching type change-over switch that can quickly select a desired input system by skipping an input system to which no signal is input when selecting an input system by simply providing a simple circuit. It is an object of the present invention to provide a signal processing apparatus having the above and a signal reproducing apparatus including the same.

  To achieve the above object, the present invention provides a plurality of input systems, an A / D converter that converts an analog signal input to each of the input systems into a digital signal, and an output from the A / D converter. The signal processing unit that receives the digital signal, the reproduction output unit that outputs one of the signals input to the signal processing unit, and the input system of the signal that is output to the reproduction output unit are sequentially switched. An input switching unit; an operation unit that outputs a switching signal that is operated by a user to switch the input system; and a control device that receives the switching signal from the operation unit and causes the input switching unit to switch the input system. A diode having an anode connected to the output of the A / D converter and a cathode connected to the control device between the A / D converter and the control device. And a capacitor having one end connected to the anode of the diode and the other end grounded, and when the voltage output from the rectifier is less than a predetermined voltage, input the corresponding input system It is characterized by skipping when the system is switched.

  The present invention also receives a plurality of input systems, an A / D converter that converts an analog signal input to each of the input systems into a digital signal, and the digital signal output from the A / D converter. A signal processing unit, an input switching unit that sequentially switches the input system of the signal output from the signal processing unit, an operation unit that outputs a switching signal that is operated by a user to switch the input system, And a control device that receives the switching signal from the operation unit and causes the input switching unit to switch the input system. An anode is provided between the A / D converter and the control device. A diode connected to the output of the D / D converter and having a cathode connected to the control device and a capacitor having one end connected to the anode of the diode and the other end grounded. Comprising a rectifier, when the voltage output from the rectifier is less than the predetermined voltage, characterized by skipping the input lines corresponding to the time of switching of the input system.

  According to the present invention, in the signal processing device having the above configuration, an OR circuit is provided between the A / D converter and the rectifier.

  A signal processing apparatus according to the present invention includes the signal processing apparatus having the above-described configuration and a reproduction output unit that outputs any of the signals input to the signal processing unit.

  According to the present invention, it is possible to detect that a signal is input to the input system only by providing a simple circuit composed of a comparator, a diode, and a capacitor in a signal reproducing device having a conventional configuration. Since an input system to which no AV device is connected or an input system to which a signal from the AV device is not input can be skipped, a desired input system can be quickly selected.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a display device which is a signal reproducing device according to the present invention, and FIG. 2 is a circuit diagram of a signal detection circuit.

  As shown in FIG. 1, the display device 10 can be connected to a playback output unit 11 composed of a device for displaying images such as a liquid crystal panel or a CRT, or a device for outputting sound such as a speaker, or a AV device such as a video deck or a DVD player. A / D converters 16a, 16b, 16c, 16d that receive analog signals input from the input systems 12a, 12b, 12c, 12d, and input systems 12a, 12b, 12c, 12d, respectively, and convert them into digital signals Controls the overall operation of the display device 10 and the signal processing unit 13 that receives signals output from the A / D converters 16a, 16b, 16c, and 16d and outputs a signal based on one of the signals to the reproduction output unit 11. The control device 14 that receives the signals from the operation unit 15 and the remote controller 20 for the user to directly operate the display device 10 such as volume control. Comprising a remote control signal control unit 17 for transmitting a signal based on the signal to the controller 14.

  The operation unit 15 and the remote controller 20 are provided with input system switching buttons 15a and 20a for selecting an input system to be output from the reproduction output unit 11 by the user from any of the input systems 12a, 12b, 12c, and 12d. The signal processing unit 13 is provided with an input switching unit 13a for switching the output from the reproduction output unit 11 to any one of the input systems 12a, 12b, 12c, and 12d based on the operation of the input system switching buttons 15a and 20a. It has been.

  Each input system 12a, 12b, 12c, 12d is provided with a video signal input terminal to which a video signal is input and an audio signal input terminal to which an audio signal is input. The video signal input terminal is an S terminal, a CVBS (Composite Video Burst Signal) terminal, or the like, and each of the input systems 12a, 12b, 12c, and 12d may include a plurality of these terminals.

  The input system switching of the display device 10 is a sequential switching type. Each time the input system switching buttons 15a and 20a are pressed, the control device 14 receives the signal and switches the input system to the input switching unit 13a of the signal processing unit 13. The input switching unit 13a switches the input system in the order of the input system 12a, the input system 12b, the input system 12c, the input system 12d, and the input system 12a.

  In the present embodiment, rectifiers 31a, 31b, 31c, and 31d are provided between the A / D converters 16a, 16b, 16c, and 16d and the control device 14, respectively. The rectifiers 31a, 31b, 31c, and 31d include a diode 33 and a capacitor 34 as shown in FIG. FIG. 2 shows only the A / D converter 16a. Hereinafter, the A / D converter 16a will be described as an example, but the same applies to other A / D converters.

  The anode of the diode 33 is connected to the output terminal of the A / D converter 16a. The cathode of the diode 33 is connected to one end of the capacitor 34 and the control device 14, and the other end of the capacitor 34 is grounded.

  The digital signal output from the output terminal of the A / D converter 16 a is smoothed by the rectifier 31 a and input to the control device 14. In the control device 14, when a voltage equal to or higher than a predetermined voltage V1 (for example, 0.5 V) is input from the signal detection circuit 30a, it is recognized that a signal is input to the corresponding input system (in this case, the input system 12a).

  Since the digital signal output from the output terminal of the A / D converter 16a is composed of Hi and Lo, when this signal is directly input to the control device 14, the Hi part is input to the terminal of the corresponding input system. Can be detected by the control device 14, but cannot be detected at the Lo portion because the voltage is low. However, in the present embodiment, a signal obtained by smoothing the digital signal is input to the control device 14 by the rectifier 31a having a simple configuration including the diode 33 and the capacitor 34, so that the signal is input to the terminal of the input system 12a. The control device 14 can reliably detect that a digital signal is being output from the output terminal of the A / D converter 16a, that is, that a signal is being input to the terminal of the input system 12a. .

  With this configuration, when the input system switching buttons 15a and 20a are pressed to switch the input system, it is possible to skip the input system in which no signal is input by the control device 14.

 For example, it is assumed that the input system 12c is selected at the present time, the signals are input to the input systems 12b and 12c, and no video signal is input to the input systems 12a and 12d. In this case, assuming that the input system 12b is desired, conventionally, the input system switching buttons 15a and 20a have to be pressed a total of three times to switch from the input system 12c to the input systems 12d, 12a and 12b. However, according to the present invention, since the input systems 12a and 12d to which no signal is input are skipped, the input system 12b can be quickly selected by simply pressing one of the input system switching buttons 15a and 20a. .

  Further, in the present embodiment, when image playback is started on a device connected to any of the input systems 12a, 12b, 12c, and 12d, the control device 14 of the display device 10 detects a signal from the device and You may make it select the input system to which the apparatus was connected. Thereby, even if it does not operate input system change button 15a, 20a, the input system to which the apparatus was connected can be selected automatically only by operating a desired apparatus. In this case, another input system may already be selected and a signal may be input through a plurality of input systems, and the input system in which input was last started may be selected with priority.

  In the present embodiment, when the display device 10 is in a standby state, when playback of an image is started with a device connected to any of the input systems 12a, 12b, 12c, and 12d, the control device 14 starts from the device. May be detected to turn on the main power of the display device 10 and select an input system to which the device is connected. Thereby, even if it does not operate the display apparatus 10, the main power supply of the display apparatus 10 can be turned on only by operating a desired apparatus, and the input system | strain to which the apparatus was connected can be selected automatically.

  In any of the above cases, the control device 14 may display an OSD to indicate which of the input systems 12a, 12b, 12c, and 12d is input.

  In the present embodiment, an OR circuit 18 may be provided between the A / D converter 16a and the rectifier 31a as shown in the circuit diagram of FIG. The OR circuit 18 has the same number of input terminals as the number of bits of the A / D converter 16a, and one output terminal of the A / D converter 16a is connected to each input terminal. With this configuration, if a signal is output from one of the output terminals of the A / D converter 16a, the signal is output from the OR circuit 18, and therefore, the signal is input to the terminal of the input system 12a. It can be reliably detected by the control device 14. Although only the input system 12a is shown in FIG. 3, an OR circuit may be provided similarly for other input systems. FIG. 3 shows an example in which the number of bits is 4, but the number of bits is not limited to this.

  In the present embodiment, the display device 10 is provided with an output terminal such as a headphone jack, the A / D converter having the above-described configuration is provided between the output terminal and the signal processing unit 13, and the A / D converter. A rectifier having the above-described configuration may be provided between the control device 14 and the control device 14. When it is detected that a signal is input to the output terminal, the control device 14 switches the input system to the output terminal, thereby connecting a headphone stereo, an MP3 player, or the like using the output terminal as an input terminal. In addition, audio can be output from the reproduction output unit 11.

  Here, FIG. 4 shows a signal output from the A / D converter 16a when an audio signal having a period of 1 μsec (frequency of 1 kHz) and an amplitude of 0.3 V is input to the audio signal input terminal of the input system 12a. The graph of the change of the voltage of the signal input into the control apparatus 14 from the rectifier 31a is shown. In the graph of FIG. 4, the horizontal axis represents time, and the vertical axis represents voltage. In addition to the signal output from the A / D converter 16a indicated by the broken line and the signal input to the control device 14 indicated by the solid line, the voice A signal input to the signal input terminal is indicated by a one-dot chain line. Similar results were obtained with the input systems 12b, 12c, and 12d.

  As can be seen from FIG. 4, when the signal input to the audio signal input terminal is a positive voltage, a voltage of about 5 V is output from the A / D converter 16a, and the signal input to the audio signal input terminal is negative. Is not output from the A / D converter 16a. Thus, a voltage of about 4.2 V obtained by smoothing the signal composed of Hi and Lo output from the A / D converter 16 a by the rectifier 31 a is input to the control device 14. Since the control device 14 recognizes that a signal is input to the terminal when a voltage equal to or higher than a predetermined voltage V1 (for example, 0.5 V) is input, during the period in which the signal is input to the terminal of the input system 12a. The control device 14 can reliably detect that a signal is input to the terminal of the input system 12a.

  The display device 10 may include a television signal receiving unit, or may reproduce and output only audio. When the television signal receiving unit is provided, the television signal receiving unit may be handled as one of the input systems.

  The present invention can be used for an electronic apparatus having an input system that is switched by a sequential changeover type changeover switch.

The block diagram of the display apparatus which is the signal reproducing | regenerating apparatus concerning this invention Circuit diagram of a signal detection circuit according to the present invention Circuit diagram of signal detection circuit provided with OR circuit Graph of change in voltage of signal input to control device from signal detection circuit

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Display apparatus 11 Reproduction | regeneration output part 12a Input system 12b Input system 12c Input system 12d Input system 13 Signal processing part 13a Input switching part 14 Controller 15 Operation part 15a Input system switching button 16a A / D converter 16b A / D converter 16c A / D converter 16d A / D converter 17 Remote control signal controller 18 OR circuit 20 Remote control 20a Input system switching button 31a Rectifier 31b Rectifier 31c Rectifier 31d Rectifier 33 Diode 34 Capacitor

Claims (4)

A plurality of input systems; an A / D converter that converts an analog signal input to each of the input systems into a digital signal; and a signal processing unit that receives the digital signal output from the A / D converter; A reproduction output unit that outputs one of the signals input to the signal processing unit, an input switching unit that sequentially switches the input system of the signal output to the reproduction output unit, and a user operating In a signal reproduction device comprising: an operation unit that outputs a switching signal for switching the input system; and a control device that receives the switching signal from the operation unit and causes the input switching unit to switch the input system.
Between the A / D converter and the control device, the anode is connected to the output of the A / D converter and the cathode is connected to the control device, and one end is connected to the anode of the diode. It has a rectifier consisting of a capacitor with a grounded end,
When the voltage output from the rectifier is less than a predetermined voltage, the corresponding input system is skipped when the input system is switched. A plurality of input systems; an A / D converter that converts an analog signal input to each of the input systems into a digital signal; and a signal processing unit that receives the digital signal output from the A / D converter; An input switching unit that sequentially switches the input system of the signal output from the signal processing unit, an operation unit that outputs a switching signal that is operated by a user to switch the input system, and the operation unit from the operation unit In a signal processing device including a control device that receives a switching signal and causes the input switching unit to switch the input system,
Between the A / D converter and the control device, the anode is connected to the output of the A / D converter and the cathode is connected to the control device, and one end is connected to the anode of the diode. It has a rectifier consisting of a capacitor with a grounded end,
When the voltage output from the said rectifier is less than predetermined voltage, the said input system is skipped in the case of switching of an input system, The signal processing apparatus characterized by the above-mentioned.   The signal processing apparatus according to claim 2, further comprising an OR circuit between the A / D converter and the rectifier.   A signal reproduction device comprising: the signal processing device according to claim 2 or 3; and a reproduction output unit that outputs any of the signals input to the signal processing unit.

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