KR20030028001A - Circuit for adjusting synchornization and video signal - Google Patents

Abstract

PURPOSE: A circuit for controlling a synchronous signal and a video signal of a monitor is provided to generate a synchronous signal and a video signal to display the signals on the monitor screen when no signal is inputted to the monitor to allow a user to view the current screen state. CONSTITUTION: A circuit for controlling a synchronous signal and a video signal of a monitor includes a microcomputer(10), a deflection circuit(20), the first and second switches(50,40). The microcomputer uses a self test signal and a horizontal synchronous signal as input signals to recognize a no-signal state of the monitor, and generates a horizontal synchronous signal and a video signal to output the signals to a video signal processing circuit when no signal is inputted to the monitor. The deflection circuit applies electric field or magnetic filed to electron beams transmitted to the monitor screen to control the traveling direction of the electron beams. The first switch uses the horizontal synchronous signals as an input signal to selectively control the horizontal synchronous signal not to be transmitted to the deflection circuit in the no-signal state. The second switch inputs the horizontal synchronous signal generated by the microcomputer to the deflection circuit when no signal is inputted to the monitor.

Description

CIRCUIT FOR ADJUSTING SYNCHORNIZATION AND VIDEO SIGNAL}

The present invention relates to a monitor. More particularly, the present invention relates to a synchronization and video adjustment circuit of a monitor that allows the user to view the current screen state by making a synchronization signal and a video signal on a screen when no signal is input to the monitor.

In the production of the monitor, the monitor screen is adjusted using a monitor screen adjusting device. In other words, the personal computer, monitor and control equipment are connected to each other to perform screen adjustment. At this time, the image displayed on the screen of the monitor is acquired from the control equipment equipped with the camera with preset values for correction of horizontal and vertical positions and sizes, side pincushion, trapezoidal distortion, etc. in the personal computer. The horizontal and vertical position and size information of the information is transmitted to the personal computer. If the personal computer compares the input value with the set value, the personal computer stores the value in the monitor's microcomputer. Otherwise, the personal computer continuously increases or decreases the value until it matches the value set in the personal computer. It is.

However, such a monitor screen adjustment device has a problem that the overall productivity is lowered because the adjustment method is somewhat complicated and the adjustment time is long. Accordingly, an adjustment circuit for performing necessary adjustments without using a personal computer is used.

1 is a schematic block diagram of a synchronization and video adjustment circuit of a conventional monitor. Referring to FIG. 1, a self test (ST) signal is applied to the microcomputer 1, and a horizontal synchronization (HS) signal is applied to the microcomputer 1 and the deflection circuit 2, respectively. If the self-test signal is not applied, that is, the monitor is not connected to the personal computer (PC), the microcomputer 1 recognizes the situation where no signal is input and displays the self-test screen on the screen of the monitor.

At this time, the horizontal synchronization signal is simultaneously applied to the microcomputer 1 and the deflection circuit 2. The microcomputer 1 applies the horizontal synchronizing signal HS to the deflection circuit 2 during self-test, and can adjust the frequency output to the deflection circuit 2 during self-test.

However, the sync and video adjustment circuits of the monitor described above can be said to have no problems when self-testing. However, interference may occur when the user of the monitor is connected to a personal computer and the monitor. That is, when a normal signal is applied to the microcomputer 1 and the deflection circuit 2, since the horizontal synchronization signal HS is applied to the deflection circuit 2 in the microcomputer 1, the deflection circuit and the microcomputer 1 Noise may occur due to mutual interference in (2).

In addition, when the input signal is not input to the monitor, that is, the video signal cannot be displayed on the screen when no signal is input, the oscillation frequency of the deflection circuit 2 becomes too low when the horizontal synchronization signal is not applied. That is, if the frequency inner range of the deflection circuit 2 is set to 30 to 100 KM, the free oscillation frequency of the deflection circuit 2 may be much lower than that to 26 KM, which may cause damage to components of the monitor.

An object of the present invention is to solve the above-mentioned problems of the prior art, the synchronization signal and the video signal is output from the microcomputer to display the monitor screen when no signal is applied to the monitor, the normal signal to the monitor When applied, a synchronization signal is directly received through a signal cable to provide a synchronization and video adjustment circuit of a monitor that can eliminate noise interference occurring in a microcomputer and a deflection circuit.

1 is a schematic block diagram of a synchronization and video adjustment circuit of a conventional monitor.

2 is a synchronization and video adjustment circuit diagram of a monitor according to the present invention.

* Description of the symbols for the main parts of the drawings *

10: microcomputer

20: deflection circuit

30: video signal processing circuit

40: second switching unit

50: first switching unit

R1-R6: resistance

D1-D2: Diode

TR1-TR2: Transistor

ST signal: Self test signal

HS signal: Horizontal synchronization signal

In order to achieve the above object, the synchronization and video adjustment circuit of the monitor according to the present invention recognizes the non-signal state of the monitor using the self test signal and the horizontal synchronization signal as input signals, A microcomputer for generating a horizontal synchronous signal and a video signal and outputting the video signal to a video signal processing circuit; A first switching unit for selectively switching and controlling the horizontal synchronization signal to not be transmitted to the deflection circuit in the non-signal state as an input signal, and the self-leveling horizontal synchronization signal output from the microcomputer upon the non-signal input And a second switching unit for inputting the circuit.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the synchronization and video adjustment circuit of the monitor according to the present invention.

2 is a synchronization and video adjustment circuit diagram of a monitor according to the present invention. Referring to FIG. 2, the synchronization and video adjustment circuit of the monitor according to the present invention recognizes a non-signal state of the monitor using the self test (ST) signal and the horizontal synchronization (HS) signal as input signals. The microcomputer 10 generates its own horizontal synchronizing signal and video signal at the time of input and outputs it to the video signal processing circuit 30, and applies an electric field or a magnetic field to the electron beam delivered to the screen of the monitor to adjust the direction of movement of the electron beam. A deflection circuit 20 and a first switching unit 50 for selectively switching and controlling the horizontal synchronous signal not to be transmitted to the deflection circuit 20 in the non-signal state using the horizontal synchronous signal as an input signal; A second switching unit 40 for inputting the self-aligned horizontal synchronization signal output from the microcomputer 10 to the deflection circuit 20 when no signal is input, and output from the microcomputer 10. It receives its own video signal consists of a video signal processing circuit 30 for processing the signal.

Here, the first switching unit 50 includes a transistor TR2, resistors R4 and R5 connected in parallel to the base of the transistor TR2, a resistor R6 and a diode connected in parallel to the collector of the transistor TR2. It consists of (D2).

In addition, the second switching unit 40 is the same as the first switching unit 50, the transistor TR1, the resistors R1 and R2 connected in parallel to the base of the transistor TR1, and the collector of the transistor TR1. It consists of a resistor (R3) and a diode (D1) connected in parallel to.

Referring to the operation of the synchronization and video adjustment circuit of the monitor according to the present invention having such a configuration as follows.

First, a self test (ST) signal and a horizontal synchronization (HS) signal are applied to the microcomputer 10 in the same manner as in the related art.

At this time, when no signal is applied to the monitor, the horizontal synchronization signal is not output. Therefore, since the transistor TR2 of the first switching unit 50 is turned off, there is no horizontal synchronization signal applied to the deflection circuit 20. Therefore, the self horizontal synchronizing signal output from the microcomputer 10 is supplied to the deflection circuit 20 through the transistor TR1 of the second switching unit 40.

In this case, the frequency may be converted into a desired frequency band according to software embedded in the microcomputer 10, and the video signal output to the video signal processing circuit 30 may also be synchronized according to the frequency. That is, when no signal is applied to the monitor, the microcomputer 10 may generate a self-synchronization signal and a video signal and display the signal on the screen. In addition, since its own signal is displayed on the monitor screen during production, a Heat Run Test can be executed without a separate normal signal.

The synchronization and video adjustment circuit of the monitor according to the present invention described above can perform a sufficient heat run test (Heat Run Test) because the frequency can be outputted when no signal is applied to the monitor. When a signal is input, the synchronous signal may be separated from the microcomputer to eliminate noise generated between the microcomputer and the deflection circuit.

In addition, even when no signal is applied to the monitor, the screen state can be seen, and it provides an effect of greatly improving productivity because it provides a condition for applying a load.

Although the present invention described above has been described by taking a monitor as an example, the present invention may be similarly applied to an image display apparatus that scans an electron beam on a screen like a monitor.

Claims (1)

A microcomputer that recognizes the signal-free state of the monitor using the self-test signal and the horizontal synchronous signal as input signals, and generates its own horizontal synchronous signal and video signal and outputs them to the video signal processing circuit when such a signal is input; A deflection circuit for adjusting an advancing direction of the electron beam by applying an electric field or a magnetic field to the electron beam delivered to the screen of the monitor; A first switching unit for selectively switching and controlling the horizontal synchronous signal not to be transmitted to the deflection circuit in the non-signal state using the horizontal synchronous signal as an input signal; And a second switching unit for inputting the self-aligned horizontal synchronizing signal output from the microcomputer to the deflection circuit when the signal is not input.