JPH0756542Y2 - Input / output circuit for AV equipment with insertion and circuit expansion functions - Google Patents

Description

TECHNICAL FIELD The present invention relates to an input / output circuit for AV equipment, and more particularly to a circuit configuration for input selection and extraction processing thereof.

2. Description of the Related Art In recent years, an input line selector that selectively extracts a plurality of AV device outputs as one AV device input and at least one AV device output have been selected due to the necessity of video information processing. Various input distributors for distributing as AV device inputs, or input / output switch circuits having both functions, so-called matrix switchers, have been developed.

However, these devices selectively distribute the input group assigned to themselves to their output terminals, and the function of simply selecting the AV device output on the input side also has the function of selecting one of the AV device outputs. It has been common to perform the function of selecting the data after passing it through various processors once by increasing the number of input pole contacts of one switch correspondingly.

Therefore, in an input / output switch circuit, a video signal measuring circuit, etc., information from each input terminal is first processed by a processor such as a color corrector, and the number of inputs is greater than the number of input lines. If the functions to be added to the above can be achieved by increasing the required minimum number of parts, a wider range of video input processing will be possible.

The present invention is intended to provide an input / output circuit for AV equipment in which the processor or accessory insertion function and line extension function as described above are configured without using complicated switch elements.

Means for Solving the Problems To achieve the above-mentioned object, the present invention provides a plurality of input lines A, B, which respectively lead to input terminals of an amplifier.
Double throw switches SWA, SWB for selecting one input for C ...
With connecting SWC ... the output-side contact of the main input terminals A ₁ for the first input contact a _1, b _1, c ₁ ... each input line of each double-throw switch, B _1, C ₁ ... and through terminals
, A _T , B _T , C _T , respectively. Further, the second input side contacts a ₂ , b ₂ , c ₂ ... of each of the double throw switches are connected to the sub input terminal A ₂ for each input line. , B _2, C ₂ ... each with connecting to the respective through terminals _{a T, B T, C T} ... respectively turned on between a ground potential - resistor terminating matching through the off switch means R _T1 And an terminating matching resistor R _T2 is directly inserted between each of the sub input terminals A ₂ , B ₂ , C ₂ ... And the ground potential, thereby forming an input / output circuit for AV equipment. It was done.

In this case, if the on-off switch means for inserting the resistor R _T1 is composed of a dummy plug that can be inserted into the corresponding through terminals A _T , B _T , C _T, ... Since it is not necessary to provide an on / off switch for the number of lines, the device can be simplified.

The present invention has the above-mentioned configuration, wherein the first input at the main input terminal and the second input at the sub input terminal are selectively used, or the first input is performed by a processor connected between the through terminal and the sub input terminal. It is possible to select three input states consisting of processing the input and then sending it to the latter stage. Furthermore, by double-connecting two similar input / output circuits of the present invention, the number of input selections can be doubled. Will also be possible.

Embodiment FIG. 1 is a circuit diagram showing the basic configuration of one input line in an embodiment of the present invention. In FIG. 1, (1) is the input line in which the amplifier (2) is inserted, and the line (1)
The output side contact (pole contact) of the double throw switch SWA for 1-input selection is connected to the start end of the, and the main input terminal A ₁ is connected to the first input side contact a ₁ of this double throw switch by line L _1. To be done. The sub input terminal A ₂ is connected to the second input side contact a ₂ of the double throw switch SWA by the line L ₂ . line
A through terminal A _T is connected to L ₁ , and a termination matching resistor R _T1 is inserted between the through terminal A _T and the ground potential via an on-off switch SWT. Further, a second termination matching resistor R is provided between the line L ₂ and the ground potential.
_T2 is directly inserted.

In the above basic input line configuration, main input terminal A ₁
Is connected to the main input (3), and the sub-input terminal A ₂ is usually connected to the sub-input (4) consisting of various external inputs. Further, in another embodiment, instead of connecting the input (4) to the sub-input terminal A _2, to insert the various processors (5) between the through terminal A _T this sub input terminal A _2.

As the first normal operating state of the input line, the double throw switch SWA is turned to the first contact a ₁ side, and the main input is supplied to the subsequent stage via the amplifier (2). At this time, since the through signal is unnecessary, the switch SWT is turned to the on side, that is, the a _r side, and the termination matching resistor R _T1 is connected. In this case, instead of connecting switch SW _T and resistor R _T1 ,
A dummy plug P _D to which the resistor R _T1 is connected and held may be inserted into the terminal A _T.

Next, if you want to correct the signal input from the main input terminal A ₁ by using various processors, such as color corrector, insert the processor between the terminals A _{T and} A ₂ and connect the switch SWA to the a ₂ side. And switch SWT to the a ₀ side. In this mode, the original signal input from the terminal A _{1 is} output from the switch terminal A _T to be supplied to various processors, and after being processed, the original signal is input to the sub input terminal A ₂ to switch the switch.
It is supplied to the amplifier (2) via SWA. This is the so-called accessory insertion function.

If you want to receive another signal in addition to the original signal from the main input terminal A ₁ , connect the required external input to the sub input terminal A ₂ instead of the output of various processors, and switch.
It will be immediately understood that by pulling SWA to the a ₂ side, its external input may be received. Then, the circuit expansion function as described below can be exerted by utilizing such a selection operation of the two-system signals in one line.

FIG. 2A doubles the number of input selections by cross-connecting two input / output circuits of, for example, three lines according to the configuration of the present invention in order to exert the above-mentioned circuit expansion function. This is the state in which the above is done. Second
In FIG. A, a first input / output circuit (6) and a second input / output circuit (7) both have basic input / output lines similar to those in FIG. 1 in blocks (6a), (6b), (6c) and (7
As shown in a), (7b), and (7c), three sets are provided.
However, the second line (6b), (7b) and the third line (6
In c) and (7c), the terminal groups corresponding to the terminal groups A ₁ , _AT , and A ₂ of the first line are B ₁ , B _T , B ₂ and C ₁ , C _T , C ₂ for convenience of description.
Display as. In this example, the main input terminals A ₁ , B ₁ and C ₁ of the first input / output circuit (6) have input signals S ₁ , S ₂ and
Main input terminal of the second input / output circuit (7) by connecting S ₃
Input signals S ₄ , S ₅ , and S ₆ are connected to A ₁ , B ₁ , and C ₁ , respectively. The S ₁ , S ₂ , and S ₃ input to the first input / output circuit (6) are sub-connected to the second input / output circuit (7) via corresponding through terminals A _T , B _T , and C _T in the circuit. Connected to input terminals A ₂ , B ₂ , and C ₂ , respectively. In addition, the signal input to the second input / output circuit (7)
S _4, S _5, S ₆ are through terminals A _T corresponding during its circuit, B
Sub input terminals A ₂ and B of the first input / output circuit (6) via _T and C _T
2 and C ₂ , respectively. Therefore, the switches SWA and SA are connected from the line output terminals of the first input / output circuit (6).
The main inputs S ₁ , S ₂ , S ₃ are output via B and SWC, respectively, or S ₄ , S which are the main inputs of the second input / output circuit (7).
₅ , selected to output S ₆ . Similarly, each line of the second input / output circuit (7) outputs the main inputs S ₄ , S ₅ , S ₆ via the switches SWA, SAB, SWC, respectively, or the first input / output circuit (6) Are selected to output the main inputs S ₁ , S ₂ , S ₃ at.

The connection shown in FIG. 2A is an example in which each input between corresponding lines is cross-connected in a pair of input / output circuits. However, as shown in FIG. If the circuit is constructed in a cascaded manner by connecting one input line, eg the through terminal of (6a), to the next line of the circuit (6), eg the main input terminal of (6b), then for a particular input, eg S ₁ It is also possible to configure a distributor that allows more distribution. If the number of sub-input terminals is increased to A ₂ , A ₃ , A _4, ... and the number of input contacts of the input selection switch SWA is increased to a ₂ , a ₃ , a _4, ... It is possible to develop a multi-input, multi-distribution matrix switcher.

FIG. 3 shows two 3 × 3 cross connections of the pair of 3 line input / output circuits (6) and (7) described in FIG. 2A.
This shows the mode used as the input circuit of the matrix switcher (however, the switches SWA, SAB, and SWC are schematically shown by lines), and according to this, only the input signal originally assigned to itself can be selectively distributed. It is also possible to selectively extract the input signals assigned to other matrix switchers from the input and output terminals of each matrix switcher, which has the same effect as configuring a matrix switcher that doubles the number of matrix elements. Is shown.

Effect of the Invention As described above, according to the circuit configuration of the present invention, since it is an input / output system in which three system terminals including a main input, a through output, and a sub input are set, an insertion circuit may be configured in addition to the main input. The sub-input can be taken out from other equipment signals, and further, the input / output circuit can be added with the input / output circuit expansion function, and thus it can be extremely effective as an input processing device for video signals.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a basic circuit configuration in an embodiment of the present invention, and FIGS. 2A and 2B are schematic diagrams showing a state in which two sets of multisystem input / output circuits having the basic circuit shown in FIG. 1 are cross-connected. A diagram, FIG. 3 is a schematic diagram showing two sets of matrix switchers with input / output circuits consisting of the connections of FIG. (1) …… Input line (2) …… Amplifier (3) …… Main input (4) …… Sub input (5) …… Processor (6) …… First input / output circuit (7) …… First 2 I / O circuit

Claims (2)

[Scope of utility model registration request] 1. Output terminals of double throw switches SWA, SWB, SWC ... for selecting one input are respectively connected to a plurality of input lines A, B, C, ... First input side contacts a ₁ , b ₁ , c _1, ...
Was connected to the main input terminal _{A 1, B 1, C 1} ... respectively and through the terminal A _T of, B _T, C _T ... each for each input line,
Further, the second input side contacts a ₂ , b ₂ , c _{2 of} each of the double throw switches
Is connected to each of the sub-input terminals A ₂ , B ₂ , C ₂ for each input line, and each of the through terminals A _T , B _T , C _T ... and the ground potential is turned on- Insert the termination matching resistor R _T1 through the off switch means, the sub-input terminal A ₂ ,
An input / output circuit for AV equipment, wherein a termination matching resistor R _T2 is directly inserted between B ₂ , C ₂ ... and the ground potential. 2. The on-off switch means for inserting the resistor R _T1 comprises a dummy plug which can be inserted into the corresponding through terminals A _T , B _T , C _T.
Switch circuit described in.