JPS62110387A - Switching device - Google Patents

Abstract

PURPOSE:To obtain an image small in ringing color deviation and high in sharpness by providing the amplifier circuit of RGB signal and switching the characteristic of a frequency characteristic switching circuit by interrupting the output of an amplifier circuit by a switch interlocked with the operation of an adapter. CONSTITUTION:RGBAV control signal is amplified by an amplifier circuit constituted of transistors 5, 8 and the output is transmitted to a frequency characteristic switching circuit. A switch 9 is opened when an adapter is connected to a power source terminal and closed when not connected. Accordingly, when the adapter that converts from RGB8 pin input to 21 pin input is connected, the switch 9 opens and sends the switching signal of about 12V to the frequency characteristic switching circuit 10, and frequency characteristic suitable for RGB8 pin input is amplified by an amplifier 1 and supplied to a cathode-ray tube 2. In the case of the equipment of RGB21 pin input that does not use the adapter, the switch 9 is kept closed and the characteristic becomes frequency characteristic suitable for RGB21 pin input.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to a television receiver equipped with only an RGB 21-pin input terminal and an adapter for converting from an RGBs pin input to an RGB 21-pin input. The present invention relates to a switching device that can be used.

Conventional technology In general, in television receivers that can receive RQB signals as input, as shown in Fig. 4, input RGB
The signal is amplified by an amplifier 1 and supplied to a cathode ray tube 2 for display.

Problems to be Solved by the Invention However, in such a configuration, the signals of the RGB 8 pin input or the RGB 21 bin input are similarly amplified.

Many RGBs pin input signals have high frequency components, such as character signals from personal computers. Many of the RGB 21 pin input signals include signals with low frequency components, such as graphic signals from a teletext broadcast reception tap. Therefore, if these are amplified using an amplifier with the same frequency characteristics,
When the characteristics match the RGBs pin input, overshoot and ringing will become noticeable in the character multiplex reception signal, and conversely, when the characteristics match the RGB 21 pin input, the character signal of the personal computer with the RGBs pin input will become noticeable. This results in disadvantages such as decreased sharpness and increased color shift.

The present invention solves these conventional problems, and provides a switching device that can obtain appropriate frequency characteristics for two types of inputs, such as RGB 8-pin input and 21-pin input, with a simple configuration. It provides:

Means for Solving the Problems The switching device of the present invention includes a switch that has an RGB signal amplification circuit and is linked to the operation of an adapter that converts and supplies a signal from a second input terminal to a first input terminal. is connected to the output terminal of the amplifier circuit, and RG
The characteristics of the frequency characteristic switching circuit which receives the B signal as input is switched.

Effect: According to the switching device of the present invention, the frequency characteristic switching circuit can be switched, and for example, when the adapter is not connected to the power connector of the adapter for converting from RGBs bin input to 21-pin input, the amplifier circuit is switched. The characteristics of the frequency characteristic switching circuit are made appropriate for the RGB 21 bin input by closing the switch provided on the power supply connector and grounding the output.

In addition, if an adapter is connected to the power supply connector, by opening the switch on the connector and transmitting the output of the amplifier circuit to the frequency characteristic switching circuit, the characteristics of the frequency switching circuit can be adjusted to suit the RGB 8-bin input. 0 From the above, by switching the circuit to appropriate frequency characteristics at the time of RGBs pin input and 21 pin input,
It is possible to obtain images with little ringing color shift and high sharpness.

Embodiment Hereinafter, a switching circuit according to an embodiment of the present invention will be explained with reference to the drawings.

As shown in FIG. 1, an amplifier circuit formed of transistors 6.8 amplifies the RGBAV control signal and outputs an output to be transmitted to the frequency characteristic switching circuit. The RGBAV control signal is a signal of approximately 3v to 6v, which is approximately 12v.
Amplify to V. Further, an adapter (not shown) for converting RGBs pin input to 21-bin manual input is equipped with a power connector that is connected to a power terminal provided on the TV set body, for example, and this connector is equipped with a switch 9. It's closed.

Therefore, when an adapter that converts from RGBs pin input to 21 pin input is connected, switch 9 opens as shown in Fig. 1 and sends a switching signal of about 12V to frequency characteristic switching circuit 1o, allowing the appropriate RGBa pin input to be input. The frequency characteristics are amplified by an amplifier 1 and supplied to a cathode ray tube 2. Furthermore, in the case of an RGB 21-bin input device that does not use an adapter, the switch 9 remains closed as shown in FIG. 2, resulting in a frequency characteristic suitable for RGB 21-pin manual input.

Another embodiment is shown in FIG. This is different from the one in which the switch 9 in Fig. 1 is provided on the power supply connector.
An example is shown in which the voltage drop caused by the resistor 18 is detected by the transistor 16 and amplified by the transistors 14 and 11 to perform the same function when connecting the conversion adapter from the pin input to the 21 pin input. Terminal 1
9 becomes a lower potential than the 6V terminal, current flows, transistors 16 and 14 become conductive, and transistor 11 is turned off, opening the collector circuit of transistor 8. When the adapter is not connected, terminal 19 is closed. By being opened, transistors 16 and 14 are turned off, transistor 11 becomes conductive, and serves to close the circuit of the collector of transistor 8.

Effects of the Invention As described above, if the switching circuit of the present invention is used, RGB8
By detecting the power status of the conversion adapter for two RGB signal input terminals such as bin input and RGB 21-bin input, the RGB signal supplied to the cathode ray tube can be adjusted to have appropriate frequency characteristics when RGB 8-bin input or RGB 21-pin input is input. It can be very useful.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a switching device in an embodiment of the present invention,
FIG. 2 is a circuit diagram of a main part of the same device, FIG. 3 is a circuit diagram of a main part of a switching device of another embodiment, and FIG. 4 is a block diagram of a conventional switching device. 1...Amplifier, 2...Cathode ray tube, 3,
4,6°7.12,13,16,17,18...
・Resistor, 5゜8, 11.14, 16... Transistor, 9... Switch provided in the power supply connector, 1o... Frequency characteristic switching circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person5,
B---'r-ransisg

Claims (1)

[Claims] an adapter that converts signals from a first RGB signal input terminal and a second RGB signal input terminal and supplies the converted signals to the first RGB signal input terminal; and an RGB signal amplification circuit in conjunction with operation switching of the adapter. A switching device comprising a switching circuit that switches the frequency characteristics of the.