Disclosure of Invention
The invention aims to provide a four-in-one color liquid crystal television which integrates a liquid crystal computer display, a DVD, a television and high-fidelity sound into a whole, saves energy and is convenient to operate.
The purpose of the invention is realized by the following scheme: the four-in-one color liquid crystal television comprises a shell, an infrared remote controller, a key board, an infrared receiver, a main control microprocessor, a television core, a color liquid crystal display, a power circuit, a DVD (digital video disk) machine core, an audio switching circuit, an audio power amplifier and a loudspeaker set, wherein the key board, the infrared receiver, the main control microprocessor, the television core, the color liquid crystal display, the power circuit, the DVD machine core, the audio switching circuit, the; the power circuit supplies power to the units in the shell; the audio signal output of the television core and the audio signal output of the DVD core are selected by the audio switching circuit and are excited by the audio power amplifier to be played; the method is characterized in that: the device also comprises a VGA input interface connected with a computer, a computer and DVD video switching circuit, an external audio interface connected with external audio equipment and a multi-path power supply output control circuit; the video output end of the DVD machine core is connected with the first group of input ends of the computer and the DVD video switching circuit, the output end of the VGA input interface is connected with the second group of input ends of the computer and the DVD video switching circuit, and the video output ends of the computer and the DVD video switching circuit and the video output end of the TV machine core are respectively connected with the color liquid crystal display; the third group of input ends of the audio switching circuit are connected with the output end of the external audio interface; the main control microprocessor controls the multi-channel power output control circuit to supply the electric energy output by the power circuit to the television core, the color liquid crystal display, the DVD core and the audio power amplifier; the main control microprocessor controls the selection of the input signals of the audio switching circuit and the computer and DVD video switching circuit; the main control microprocessor controls the scanning mode and input signal selection of the color liquid crystal display; it has four modes of operation:
A. under the control of a television mode instruction sent to a main control microprocessor by a key on a key board or an infrared remote controller through an infrared receiver, the multi-path power output control circuit enables a television core, a color liquid crystal display and an audio power amplifier to obtain electric energy, the audio switching circuit selects the audio signal output of the television core to excite a loudspeaker set to play, and the color liquid crystal display selects the video signal output of the television core to carry out interlaced scanning display, so that the function of the television is realized;
B. under the control of a key on a key board or an infrared remote controller through a DVD mode instruction sent to a main control microprocessor by an infrared receiver, a multi-path power output control circuit enables a DVD machine core, a color liquid crystal display and an audio power amplifier to obtain electric energy, an audio switching circuit selects the audio signal output of the DVD machine core to excite a loudspeaker set to play, and a computer and a DVD video switching circuit select the video signal output of the DVD machine core to the color liquid crystal display to perform line-by-line scanning display so as to realize the function of the DVD machine;
C. under the control of a computer display mode instruction sent to a main control microprocessor by a key on a key board or an infrared remote controller through an infrared receiver, the multi-path power output control circuit enables the color liquid crystal display to obtain electric energy, and the computer and the DVD video switching circuit select a video signal of the VGA input interface to output to the color liquid crystal display for line-by-line scanning display, so that the function of the computer display is realized;
D. under the control of high-fidelity sound mode instructions sent to a main control microprocessor by keys on a key board or an infrared remote controller through an infrared receiver, the multi-path power output control circuit enables an audio power amplifier to obtain electric energy, and the audio switching circuit selects audio signals of an external audio interface to output and excites a loudspeaker set to play through the audio power amplifier, so that the function of high-fidelity sound is realized.
The television core comprises a high-frequency tuner and a video decoder; under the control of the main control microprocessor, the high frequency tuner selects the TV program signal of the appointed channel from the TV program signals provided by the TV signal interface and separates the analog quantity audio signal of the accompanying sound and the analog quantity video signal of the image, the analog quantity audio signal of the accompanying sound is output to the first group of selection input ends of the audio switching circuit, and the video decoder converts the analog quantity interlaced video signal of the image into a digital interlaced video signal and outputs the digital interlaced video signal to the color liquid crystal display.
The color liquid crystal display comprises a color liquid crystal screen driving circuit and a color liquid crystal screen connected with the output end of the color liquid crystal screen driving circuit; the color liquid crystal screen driving circuit is provided with a digital interlaced scanning input end, a built-in video A/D converter and an analog quantity input end thereof; the color liquid crystal display has two working states:
E. under the control of the main control microprocessor, the color LCD screen driving circuit selects the built-in video A/D converter to work, and converts the progressive scanning analog image signals received by the analog input end of the color LCD screen driving circuit and output by the DVD video switching circuit into digital progressive scanning driving signals to be sent to the color LCD screen for display; or,
F. under the control of the main control microprocessor, the color LCD screen driving circuit converts the digital interlaced video signal from the video decoder of the TV core received by the digital interlaced input terminal into digital interlaced driving signal for display on the color LCD screen.
The DVD player core comprises a DVD decoding servo circuit, a DVD driving and reading device, a three-primary-color RGB and line-field output circuit, an audio D/A converter and an audio amplifying circuit; under the control of main control microprocessor, DVD decoding servo circuit receives the command from the key on the key board or the infrared remote controller via the infrared receiver to control the DVD driver and reader and read out the information on CD, the DVD decoding servo circuit separates the read out CD information to obtain the digital audio signal of the accompanying sound and the analog video signal of the image, the audio D/A converter converts the digital audio signal of the accompanying sound into analog audio signal, the analog audio signal is amplified in the audio amplifier circuit and output to the second group of selecting input ends of the audio switch circuit, and the three-primary color RGB and line-field output circuit amplifies the analog video signal of the image and sends to the first group of selecting input ends of the computer and DVD video switch circuit.
In the high fidelity sound operating mode, images input by external videos can be displayed, and one implementation mode is as follows: the video decoder of the television core is also connected with an external video input interface; under the control of high fidelity sound mode command sent from the key or infrared remote controller to the main control microprocessor through the infrared receiver, the main control microprocessor also controls the multi-channel power output control circuit to make the color LCD obtain electric energy and make the video decoder convert the image analog quantity interlaced video signal provided by the external video input interface into digital interlaced video signal and output it to the color LCD.
In the working mode of the computer display, the sound information output by the computer audio interface can also be played, and one implementation mode is as follows: the audio switching circuit is also provided with a group of selecting ends connected with the computer audio interface; under the control of keys on the key board or an infrared remote controller through a computer display mode instruction sent to the main control microprocessor by the infrared receiver, the multi-path power output control circuit also enables the audio power amplifier to obtain electric energy, and the main control microprocessor controls the audio switching circuit to select audio signals provided by the computer audio interface to be output and then to excite the loudspeaker set to play through the audio power amplifier.
After the whole machine enters each working mode, specific operation in the working mode can be completed by using specific operation instructions sent by the key board or the infrared remote controller. One embodiment is: the output of the infrared receiver is sent to a remote control signal switching circuit, and two output ends of the remote control signal switching circuit are respectively connected with a DVD decoding servo circuit and a main control microprocessor; the output of the key board is also connected with a DVD decoding servo circuit;
G. under the control of a DVD mode instruction sent to the main control microprocessor by a key or an infrared remote controller on the key board through the infrared receiver, after the whole machine enters the state of the DVD machine to work, the main control microprocessor controls the remote control signal switching circuit to send the output of the infrared receiver to the DVD decoding servo circuit, and under the control of a specific DVD machine operation instruction sent to the DVD decoding servo circuit by the key or the infrared remote controller on the key board through the infrared receiver, the DVD decoding servo circuit controls the DVD driving and reading device to respectively execute specific DVD machine operations including warehouse-out, playing and stopping operations; or H, under the control of the television mode command sent to the main control microprocessor by the keys on the key board or the infrared remote controller through the infrared receiver, after the whole machine enters the television state to work, the master control microprocessor controls the remote control signal switching circuit to still send the output of the infrared receiver to the master control microprocessor, under the control of specific TV operation command sent to the main control microprocessor by the infrared receiver via keys on the key board or the infrared remote controller, the main control microprocessor controls the TV core to execute specific TV program operation including channel switching and system switching, or the main control microprocessor controls the color LCD to execute specific display parameter adjustment operations including brightness adjustment and contrast adjustment, or the main control microprocessor controls the audio power amplifier to respectively execute specific sound parameter adjustment operations including volume adjustment and tone adjustment operations; or,
I. under the control of computer display mode instructions sent to the main control microprocessor by keys or an infrared remote controller on the key board through the infrared receiver, after the whole computer enters the state of the computer display to work, the main control microprocessor controls the remote control signal switching circuit to still send the output of the infrared receiver to the main control microprocessor, and under the control of specific computer display operation instructions sent to the main control microprocessor by the keys or the infrared remote controller on the key board through the infrared receiver, the main control microprocessor controls the color liquid crystal display to respectively execute specific display parameter adjustment operations including brightness adjustment and contrast adjustment operations; or,
J. under the control of high-fidelity sound mode command sent from the key or infrared remote controller to the main control microprocessor through the infrared receiver, the main control microprocessor controls the remote control signal switching circuit to still send the output of the infrared receiver to the main control microprocessor after the whole machine enters into high-fidelity sound state to work, and under the control of specific high-fidelity sound operation command sent from the key or infrared remote controller to the main control microprocessor through the infrared receiver, the main control microprocessor controls the audio power amplifier to respectively execute specific sound parameter adjustment operations including volume adjustment and tone adjustment operations.
The four-in-one color LCD TV integrates color LCD computer display, TV, DVD player and high fidelity audio, and can play DVD, VCD, CD and other discs. The shared circuit part is fully utilized in the composition structure, so that the repeated arrangement of circuits is avoided, a set of key board and infrared remote controller are matched with a main control microprocessor to control each functional circuit part, and each signal switching circuit and each multi-path power output control circuit are controlled according to the use function to complete the combination of in-service circuits, so that the whole machine has the advantages of small occupied space, light weight and energy conservation; the user is completely liberated from complex signal line connection and complex operation of using functions, so that: the use is convenient, the operation is simple, and the device can be widely applied to occasions such as families, hotels, institutions, groups, schools, enterprises and public institutions and the like.
Detailed Description
The general structure of the four-in-one color liquid crystal television of the present invention is shown in fig. 1.
The four-in-one color liquid crystal television integrates a color liquid crystal computer display, a television, a DVD and a high-fidelity sound box into a whole and has various audio and video functions. The television comprises a shell, an infrared remote controller 53, a television core 1, a DVD (digital video disk) core 2, a color liquid crystal display 3, an audio power amplifier 4, a loudspeaker group 41, a main control microprocessor 5, a key board 51, an infrared receiver 52, a power supply circuit 6, a multi-path power supply output control circuit 7, a computer and DVD (digital video disk) video switching circuit 81, an audio switching circuit 82, a VGA (video graphics array) input interface 93 connected with a computer and an external audio interface 94 connected with external audio equipment, wherein the television core 1, the DVD core 2, the color liquid crystal display 3, the audio power amplifier 4. The power supply circuit 6 supplies power to the above-described units in the housing. The audio signal output end of the television core 1 is connected with the first group of input ends of the audio switching circuit 82, the audio signal output end of the DVD player core 2 is connected with the second group of input ends of the audio switching circuit 82, and the output end of the external audio interface 94 is connected with the third group of input ends of the audio switching circuit 82. The audio signal output of the television core 1, the audio signal output of the DVD player core 2 and the audio signal output of the external audio interface 94 are selected by the audio switching circuit 82 and excited by the audio power amplifier 4 to be played by the speaker group 41. The video output end of the DVD machine core 2 is connected with the first group of input ends of the computer and DVD video switching circuit 81, the output end of the VGA input interface 93 is connected with the second group of input ends of the computer and DVD video switching circuit 81, and the video output ends of the computer and DVD video switching circuit 81 and the video output end of the TV machine core 1 are respectively connected with the color liquid crystal display 3. The main control microprocessor 5 controls the multi-channel power output control circuit 7 to supply the electric energy output by the power circuit 6 to the television core 1, the DVD core 2, the color liquid crystal display 3 and the audio power amplifier 4. The main control microprocessor 5 controls the selection of the input signals of the audio switching circuit 82 and the computer and DVD video switching circuit 81. The main control microprocessor 5 controls the scanning mode and input signal selection of the color liquid crystal display 3.
The four-in-one color liquid crystal television has four working modes:
A. television mode. Under the control of a television mode instruction sent to the main control microprocessor 5 by a key on the key board 51 or an infrared remote controller 53 through an infrared receiver 52, the multi-path power output control circuit 7 enables the television core 1, the color liquid crystal display 3 and the audio power amplifier 4 to obtain electric energy, the audio switching circuit 82 selects the audio signal output of the television core 1 to excite the loudspeaker group 41 to play through the audio power amplifier 4, and the color liquid crystal display 3 selects the video signal output of the television core 1 to carry out interlaced scanning display, thereby realizing the television function.
DVD player mode. Under the control of the button on the button board 51 or the mode command of the DVD player sent from the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, the multi-channel power output control circuit 7 makes the core 2 of the DVD player, the color liquid crystal display 3 and the audio power amplifier 4 obtain electric energy, the audio switching circuit 82 selects the audio signal output of the core 2 of the DVD player to excite the speaker group 41 to play, and the computer and DVD video switching circuit 81 selects the video signal output of the core 1 of the DVD player to the color liquid crystal display 3 to perform progressive scanning display, thereby realizing the function of the DVD player.
C. Computer monitor mode. Under the control of the computer display mode command sent from the key on the key board 51 or the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, the multi-path power output control circuit 7 makes the color liquid crystal display 3 obtain electric energy, and the computer and DVD video switching circuit 81 selects the video signal of the VGA input interface 93 to output to the color liquid crystal display 3 for progressive scanning display, thereby realizing the function of the computer display.
D. High fidelity sound mode. Under the control of high fidelity sound mode command sent from the key on the key board 51 or the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, the multi-channel power output control circuit 7 makes the audio power amplifier 4 obtain electric energy, and the audio switching circuit 82 selects the audio signal output of the external audio interface 94 to be excited by the audio power amplifier 4 to the speaker group 41 for playing, so as to realize the high fidelity sound function.
The principle block structure of an embodiment of the four-in-one color liquid crystal television of the present invention is shown in fig. 2. The composition and connection relationship of the present embodiment follow the basic structure shown in fig. 1, and the operation is also the same as described above, and will not be described repeatedly below. A description will now be made of matters requiring supplementation.
The television set core 1 in this embodiment includes two parts, a high frequency tuner 11 and a video decoder 12. The high frequency tuner 11 under the control of the main control microprocessor 5 selects a television program signal of a specified channel from among television program signals supplied from the television signal interface 91 and separates an analog audio signal of an accompanying sound output to the first group of selection input terminals of the audio switching circuit 82 and an analog video signal of an image. Under the control of the main control microprocessor 5, the video decoder 12 converts the analog interlaced video signal of the picture into a digital interlaced video signal and outputs the digital interlaced video signal to the color liquid crystal display 3.
The color liquid crystal display 3 in this embodiment includes a color liquid crystal panel driving circuit 32 and a color liquid crystal panel 31 connected to an output terminal thereof. The color liquid crystal panel driving circuit 32 has a digital interlaced scanning input terminal and a built-in video a/D converter and an analog input terminal thereof. The color liquid crystal display 3 has two operating states:
1. under the control of the main control microprocessor 5, the color liquid crystal panel driving circuit 32 selects the video A/D converter in it to work, and converts the progressive scanning analog image signal received by the analog input end of the color liquid crystal panel driving circuit into the digital progressive scanning driving signal to be displayed on the color liquid crystal panel 31, and the progressive scanning analog image signal is output by the computer and DVD video switching circuit 81.
2. Under the control of the main control microprocessor 5, the color liquid crystal panel driving circuit 32 selectively converts the digital interlaced video signal outputted from the video decoder 12 of the television set core 1 received at the digital interlaced input terminal thereof into a digital interlaced driving signal, and sends the digital interlaced driving signal to the color liquid crystal panel 31 for display.
The DVD player deck 2 in this embodiment includes a DVD decoding servo circuit 21, a DVD drive and readout device 22, a three primary RGB and line field output circuit 23, an audio D/a converter 24, and an audio amplifier circuit 25. Under the control of the main control microprocessor 5, the DVD decoding servo circuit 21 receives the instruction from the key on the key board 51 or the infrared remote controller 53 via the infrared receiver 52 to operate the DVD drive and read device 22 and read the information on the CD, the DVD decoding servo circuit 21 separates the read CD information to process the digital audio signal of the accompanying sound and the analog video signal of the image, the audio D/A converter 24 converts the digital audio signal of the accompanying sound into the analog audio signal, the analog audio signal is amplified and output to the second group of selection input ends of the audio switching circuit 82 by the audio amplifying circuit 25, and the three-primary-color RGB and line-field output circuit 23 amplifies the analog line-by-line scanning video signal of the image and sends to the first group of selection input ends of the computer and the DVD video switching circuit 81.
The audio power amplifier 4 of the present embodiment is composed of a two-channel integrated circuit, and can perform volume adjustment and tone adjustment under the control of the main control microprocessor 5.
The main control microprocessor 5 of this embodiment selects an 8051 microprocessor as a platform for software work development. For software, the priority order of processing the keys on the keypad 51 or the commands sent by the ir remote 53 to the main control microprocessor 5 via the ir receiver 52 is as follows:
1. power state change (user switch power key)
2. Working mode change (user switching working mode)
3. General key state change (user operation menu caption setting key)
Lower priority events are only handled if higher priority external events do not occur.
After the whole machine enters each working mode, specific operation in the working mode can be completed by using specific operation instructions sent by the key board 51 or the infrared remote controller 53. For this purpose, the output of the infrared receiver 52 is supplied to a remote control signal switching circuit 54, and two output terminals of the remote control signal switching circuit 54 are connected to the DVD decoding servo circuit 21 and the main control microprocessor 5, respectively. The output of the keypad 51 is also connected to the DVD decoding servo circuit 21.
The present embodiment enters the operation control relationship of the television mode, the computer display mode and the hi-fi sound mode, please refer to fig. 3.
Under the control of the television mode command sent to the main control microprocessor 5 by the key or infrared remote controller 53 on the key board 51 through the infrared receiver 52, after the complete machine enters the television state and works, the main control microprocessor 5 controls the remote control signal switching circuit 54 to still send the output of the infrared receiver 53 to the main control microprocessor 5, under the control of the specific television operation command sent to the main control microprocessor 5 by the key or infrared remote controller 53 on the key board 51 through the infrared receiver 52, the main control microprocessor 5 controls the high-frequency tuner 11 of the television core 1 to respectively execute the specific television program operation including the channel switching and the system switching operation; or the main control microprocessor 5 controls the color LCD driving circuit 32 to respectively execute the display parameter adjustment operations of the specific color LCD 3 including the brightness adjustment and the contrast adjustment operations; or the main control microprocessor 5 controls the audio power amplifier 4 to respectively execute specific sound parameter adjusting operations including volume adjusting and tone adjusting operations.
Under the control of computer display mode command sent from the key on the key board 51 or the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, after the whole computer enters the computer display state and works, the main control microprocessor 5 controls the remote control signal switching circuit 54 to still send the output of the infrared receiver 53 to the main control microprocessor 5, and under the control of specific computer display operation command sent from the key on the key board 51 or the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, the main control microprocessor 5 controls the color liquid crystal screen driving circuit 32 to respectively execute specific color liquid crystal display 3 display parameter adjustment operations including brightness adjustment and contrast adjustment operations.
Under the control of the high fidelity sound mode command sent from the key or infrared remote controller 53 on the key board 51 to the main control microprocessor 5 through the infrared receiver 52, after the whole set enters the high fidelity sound state to work, the main control microprocessor 5 controls the remote control signal switching circuit 54 to still send the output of the infrared receiver 53 to the main control microprocessor 5, and under the control of the specific high fidelity sound operation command sent from the key or infrared remote controller 53 on the key board 51 to the main control microprocessor 5 through the infrared receiver 52, the main control microprocessor 5 controls the audio power amplifier 4 to respectively execute the specific sound parameter adjustment operations including the volume adjustment and the tone adjustment operations.
Please refer to fig. 4 for the operation control relationship after entering the DVD mode.
Under the control of the button on the button board 51 or the mode instruction of the DVD player sent from the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, after the complete machine enters the state of the DVD player and works, the main control microprocessor 5 controls the remote control signal switching circuit 54 to send the output of the infrared receiver 52 to the DVD decoding servo circuit 21, and under the control of the specific DVD player operation instruction sent from the button on the button board 51 or the infrared remote controller 53 to the DVD decoding servo circuit 21 through the infrared receiver 52, the DVD decoding servo circuit 21 controls the DVD drive and readout device 22 to respectively execute the specific DVD player operation including the bin-out operation, the playing operation and the stopping operation. After the whole machine enters the DVD machine state to work, the main control microprocessor 5 also monitors the keys on the key board 51 or the control operation instructions of the color liquid crystal display 3 and the audio power amplifier 4 sent by the infrared remote controller 53 through the infrared receiver 52; once receiving the above instruction, the color lcd panel driving circuit 32 is controlled to perform specific display parameter adjustment operations including brightness adjustment and contrast adjustment operations, respectively; or control the audio power amplifier 4 to perform specific sound parameter adjustment operations including volume adjustment and tone adjustment operations, respectively.
The power supply circuit 6 of the present embodiment is a dc conversion circuit that converts a 12V dc input into a 12V dc output and a 5V dc output. Wherein, the normally open 5V DC output supplies power to the main control microprocessor 5, the computer and DVD video switching circuit 81 and the audio switching circuit 82, and the other 5V DC output supplies power to the multi-channel power output control circuit 7. In addition, a power adapter with AC85-240V input and DC12V output is selected for matching with an AC power occasion.
The multi-channel power output control circuit 7 of the present embodiment supplies power to the television core 1, the DVD core 2, the color liquid crystal display 3, the audio power amplifier 4, and the VGA input interface 93, respectively, under the control of the control lines of the power control I/O port of the main control microprocessor 5. To facilitate understanding of the operation of the multi-channel power output control circuit 7, a simplified representation of the MOS transistor control circuit 71 with control terminal for supplying power to the DVD player deck 2 and the panel power supply 72 for supplying power to the color liquid crystal display 3 is given in fig. 2, 5, 6, 7 and 8. The MOS tube control circuit 71 with a control terminal for supplying power to the DVD player deck 2 is supplied with electric power from the 5V dc output of the power supply circuit 6, and supplies power to the DVD decoding servo circuit 21, the DVD drive and readout device 22, the three primary color RGB and line-field output circuit 23, the audio D/a converter 24, and the audio amplifier circuit 25 of the DVD player deck 2 under the control of the power supply control I/O port DVD control line of the main control microprocessor 5. The panel power supply 72 for supplying power to the color liquid crystal display 3 is supplied with electric power from the 12V dc output and the 5V dc output of the power supply circuit 6, and supplies power to the color liquid crystal panel 31 and the color liquid crystal panel drive circuit 32 of the color liquid crystal display 3 under the control of the power supply control line of the power supply control I/O port of the main control microprocessor 5.
In the present embodiment, in the working mode of the computer monitor, the audio information outputted from the computer audio interface 95 can also be played. The computer audio interface 95 is connected to the fourth set of selection terminals of the audio switching circuit 82. Under the control of the key on the key board 51 or the computer display mode command sent from the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, the multi-channel power output control circuit 7 also makes the audio power amplifier 4 obtain power, and the main control microprocessor 5 controls the audio switching circuit 82 to select the audio signal output provided by the computer audio interface 95 to be played through the audio power amplifier 4 to drive the speaker group 41.
In the embodiment, in the working mode of the hi-fi sound, the image input by the external video can be displayed, and the adopted method is as follows: the video decoder 12 of the television set core 1 is also connected to an external video input interface 96. Under the control of high fidelity audio mode commands sent from the buttons on the button board 51 or the infrared remote controller 53 to the main control microprocessor 5 through the infrared receiver 52, the main control microprocessor 5 also controls the multi-channel power output control circuit 7 to make the color liquid crystal display 3 obtain power, and makes the video decoder 12 convert the image analog quantity interlaced video signals provided by the external video input interface 96 into digital interlaced video signals to be output to the color liquid crystal display 3.
Corresponding to the four working modes, the present embodiment can be used as a device with four modes of television, DVD player, computer display, computer sound, hi-fi sound and external video playing. The effective block structure of these four modes of devices, please refer to fig. 5, fig. 6, fig. 7 and fig. 8, respectively.
When in use, only required external signal sources such as VGA signals and audio signals of a computer host, antenna or cable closed circuit television signals, external video (AV) signals and external audio signals need to be accessed into corresponding interfaces according to the specification. Pressing the MODE (MODE) key of the keypad 51 or the infrared remote controller 53 can select different operation MODEs: TV program is watched in TV mode, CD, VCD or DVD program is listened and watched in DVD mode, computer monitor mode is used as computer monitor and sound, and program of external video camera, video and audio is listened and watched in Hi-Fi sound mode. The manual connection of signals is not needed to be carried out on different mode selections, and the multiple purposes of one machine are really realized.
When different working modes are selected, the same key board 51 and the infrared remote controller 53 are used for operation, and the internal main control microprocessor 5 switches corresponding circuit combination and control combination according to the selected working modes. When the power supply is in work, the main control microprocessor 5 carries out timely and effective tracking control on the power supply part, and the unnecessary power supply part is turned off through the multi-path power supply output control circuit 7 under different working modes so as to realize low power consumption to the maximum extent. The user does not need to consider the internal switching relation, and only uses the embodiment as a television, a DVD player, a computer display, a computer sound, a high-fidelity sound and an external video playing device according to the requirement, so that the operation is simple and convenient.