Video input and the method for component input interface multiplexing in a kind of television receiver
Technical field
The present invention relates to the field of TV input interface, and in particular to video input and component are defeated in a kind of television receiver
The method of incoming interface multiplexing.
Background technology
With the continuous renewal of Display Technique, domestic TV continues to develop towards thinner more flat trend.With LCD TV
Traditional CRT TVs have been substituted for the flat panel TV of new generation of representative, have turned into the main flow of Polarizations for Target Discrimination in Clutter.It is handsome in appearance in emphasis
While, with set top box, DVD, media player etc. for represent it is all kinds of it is consumer enter into average family depending on, audio-frequence player device,
It is indispensable " peripheral hardware " just to turn into domestic TV.User is continuously increased to the demand of television information source interface quantity, single AV
(Video)Or YPBPR(Component)Information source interface is difficult to meet the needs of active user, it is necessary to increase the information source of multichannel multiple format
Input port.And flat panel TV due to shape itself structure the characteristics of, limitation often is proposed to the quantity of information source Interface Terminal.
Therefore, the research of docking port terminal multiplexing mode, the new direction in TV input interface field is become.
The content of the invention
Goal of the invention:In order to solve the problems, such as Interface Terminal quantity limitation in the prior art, the present invention provides a kind of TV
Video input and the method for component input interface multiplexing, are switched by signal behavior and circuit in receiver, make two kinds it is different
Signal can share same Interface Terminal, overcome the deficiencies in the prior art.
Technical scheme:Video input and the method for component input interface multiplexing, vision signal bag in a kind of television receiver
Vision signal all the way and left and right two-way audio signal are included, component signal includes luminance signal and two-way colour difference signal all the way;It is special
Sign is that vision signal and component signal share one group of terminal, and this method comprises the following steps:
1.1)For three road signals of vision signal per an input terminal is respectively equipped with all the way, three road signals of component signal are every
Share an input terminal of vision signal respectively all the way;Wherein, it is bright in the vision signal and component signal in vision signal
Spend signal and share a terminal;
1.2)Setting signal channel switching circuit, when signal is 1, circuit selection vision signal, three-line connects respectively
By from vision signal and left and right two-way audio signal;When signal is 0, circuit selection component signal, three-line is changed to connect
By luminance signal and two-way colour difference signal;
1.3)Impedance switching circuit is set, two groups of impedances, basis in work are set respectively to vision signal and component signal
Impedance corresponding to signal behavior enters circuit, when signal is 1, selects vision signal input impedance;When signal is 0, selection
Component signal input impedance.
The switching control after level conversion is carried out in circuit using switch metal-oxide-semiconductor, uses binary channels selection circuit
PI5V330Q。
Wherein, the terminal of selection is RCA signal terminals;Video input impedance is 75 Ω in vision signal, left and right two-way sound
The input impedance of frequency signal is more than 10K Ω;The input impedance of 3 interfaces in component signal is all 75 Ω.
Beneficial effect:Using same group of RCA signal terminal, by signalling channel switching circuit, realize to vision signal and
Sharing for component signal input terminal, on the premise of signalling channel quantity is ensured, is greatly reduced the number of signal input terminal
Amount, meets flat television structure demand.
Brief description of the drawings
Fig. 1 signalling channels switch schematic diagram
Fig. 2 input impedance switches schematic diagram
Embodiment
Further description is done to the present invention below in conjunction with the accompanying drawings.
Video input and the method for component input interface multiplexing, vision signal include video all the way in a kind of television receiver
Signal and left and right two-way audio signal, component signal include luminance signal and two-way colour difference signal all the way;At present, television reception
The input terminal of vision signal and component signal on machine is all to use RCA-type interface, so completely can be by two kinds of signals
Input combines, and shares a terminal, reaches the purpose for reducing by one group of terminal.
This method comprises the following steps:
1.1)For three road signals of vision signal per an input terminal is respectively equipped with all the way, three road signals of component signal are every
Share an input terminal of vision signal respectively all the way;Wherein, it is bright in the vision signal and component signal in vision signal
Spend signal and share a terminal;
1.2)Although the interface of vision signal and component signal has same physical, needed inside television receiver
Two kinds of signals are carried out with different processing, therefore, it is necessary to increase signalling channel selection circuit, as shown in figure 1, being set in this example
Signalling channel switching circuit, when signal is 1, circuit selection vision signal, three-line receives to come from vision signal respectively
(Video)An and left side(L), it is right(R)Two-way audio signal;When signal is 0, circuit selection component signal, three-line is changed to connect
By luminance signal(Y)With two-way aberration(Pb and Pr)Signal;
The a width of 6MHz of band of vision signal, a width of 40MHz of component signal band, therefore in modelled signal channel selection circuit
Fully take into account this point.This example selects core circuits of the binary channels selection circuit PI5V330Q as signalling channel,
PI5V330Q bandwidth chahnel is 200MHz, can meet the needs of this circuit completely.
1.3)Impedance switching circuit is set, two groups of impedances, basis in work are set respectively to vision signal and component signal
Impedance corresponding to signal behavior enters circuit, when signal is 1, selects vision signal input impedance;When signal is 0, selection
Component signal input impedance.
The input impedance of video and component signal is different.Video input impedance is 75 Ω in vision signal, two-way sound
Frequency signal input impedance requirement is more than 10K Ω;The input impedance of 3 interfaces in component signal is all 75 Ω.It is therefore it is necessary to right
Signaling interface input impedance switches over, as shown in Figure 2.This example switchs metal-oxide-semiconductor from 2 2N7002 types, realizes impedance
Mapping function., it is necessary to which MCU offer switch-over control signals, pass through 1 2N7002 type and switch MOS when the circuit enters row of channels conversion
Pipe switches over control after realizing level conversion to the circuit.
Switched by signalling channel, realize vision signal and component signal shares the purpose of one group of input terminal, save
One group of input terminal, the interface for improving flat panel TV are set, and save resource.
Described above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications also should
It is considered as protection scope of the present invention.