KR19990043425A - Horizontal phase automatic adjustment circuit of multi-mode monitor - Google Patents

Abstract

The present invention relates to a horizontal phase automatic adjustment circuit of a multi-mode monitor.

According to the present invention, the positive and negative components of the sensed current sensed by the deflection current sensing transformer Ts for detecting the horizontal deflection current flowing through the horizontal deflection coil H.DY are half-waves, respectively. After rectified and smoothed and noise canceled, when the comparator 30 outputs a sense current corresponding to the difference between the positive (+) component and the negative (-) component when inputted to the comparator 20, the A / D converter ( 30 is converted from the comparator 30 to the input sensing current is converted into a digital signal and applied to the microcomputer 40, accordingly, the microcomputer 40 is output from the A / D converter 30 to input the digital signal Outputs a phase correction signal for stepping down the DC level indicated to 0 (Zero), and when the D / A converter 50 converts the phase correction signal into an analog signal and applies it to the horizontal deflection current generator 10, the horizontal deflection current. Phase is automatically adjusted so that it remains constant at all times. There.

Description

Horizontal phase automatic control circuit of a multi-mode monitor

The present invention relates to a horizontal phase adjustment circuit of a multi-mode monitor.

In general, a multi-mode monitor is a monitor that reproduces a predetermined image by automatically changing circuit constants inside the monitor according to a video card type (eg, EGA, VGA, SVGA, XGA, etc.), that is, a video mode. The mode is divided by the frequency of the horizontal synchronous signal or the vertical synchronous signal. When the video mode is changed, the horizontal / vertical deflection circuit, the horizontal / vertical size control circuit, and the deflection compensation are controlled by the control signal output from the microcomputer in the multi-mode monitor. Circuit constants such as circuits are changed. In particular, the memory of the microcomputer stores horizontal phase control information for correcting a phase of a horizontal deflection current that changes according to a plurality of video modes. Such horizontal phase control information is stored in a video mode during monitor production. Each type is stored in the memory of the microcomputer.

However, even if the horizontal phase data is stored in the microcomputer as described above and the horizontal deflection current is phased every time the video mode is changed, there is a limit in actually storing the horizontal phase control information corresponding to all the videos in the microcomputer of the monitor. Therefore, when a video mode without horizontal phase data is stored in the monitor's microcomputer is input to the monitor, it is inconvenient for the user to manually operate the horizontal phase adjustment switch of the monitor. There was a problem in that it takes time to store phase control information in the microcomputer of the monitor.

Therefore, in order to solve the above problems, the present invention detects the horizontal deflection current flowing through the horizontal deflection coil (H.DY) of the monitor and automatically adjusts the phase of the horizontal deflection current even when the video mode is changed to maintain the constant state at all times. It is an object of the present invention to provide a horizontal phase automatic adjustment circuit of a multi-mode monitor.

The present invention devised to achieve the above object, the horizontal deflection current generating unit for generating a horizontal deflection current; A deflection current sensing transformer installed between one side of the horizontal deflection coil (H.DY) and the horizontal deflection current generating unit to sense a change in the horizontal deflection current; A first diode for half-wave rectifying a positive component of the sense current induced in the secondary winding of the deflection current sensing transformer; A second diode half-wave rectifying a negative component of the sense current induced in the secondary winding of the deflection current sensing transformer; A first capacitor that smoothes the positive sensing current half-wave rectified by the first diode; A second capacitor for removing noise mixed in the positive sensing current smoothed by the first capacitor; A third capacitor smoothing the negative sensing current half-wave rectified by the second diode; A fourth capacitor for removing noise mixed in the negative sensing current smoothed by the third capacitor; A comparator for comparing the DC voltage level values of the positive sensed (+) sensed current and the negative sensed (−) sensed current removed by the second capacitor and the fourth capacitor and outputting a sensed current corresponding to the difference; An A / D converter for converting a sense current output from the comparator into a digital signal; A microcomputer for outputting a phase correction signal for keeping the phase of the horizontal deflection current constant by stepping down the DC level value of the sense current indicated by the digital signal output from the A / D converter to 0 (Zero); And a D / A converter for converting a phase correction signal output from the microcomputer into an analog signal and applying the same to the horizontal deflection current generating unit.

The circuit according to the present invention configured as described above, the positive (+) component and the negative polarity of the sense current sensed by the deflection current sensing transformer for detecting the horizontal deflection current flowing in the horizontal deflection coil (H.DY) After the (-) component is half-wave rectified and smoothed and noise canceled, the comparator outputs a sense current corresponding to the difference between the positive and negative components when input to the comparator. The converter converts the sensed current output from the comparator into a digital signal and applies it to the microcomputer. Accordingly, the microcomputer outputs the DC level value indicated by the digital signal output from the A / D converter to 0 ( Outputs a phase correction signal for stepping down to zero, and the D / A converter converts the phase correction signal into an analog signal and applies it to the horizontal deflection current generating unit There is a phase is to be automatically adjusted to be always kept constant.

1 is a view showing a horizontal phase automatic adjustment circuit according to the present invention,

2 is a waveform diagram illustrating the operation of the horizontal phase automatic adjustment circuit according to the present invention.

* Explanation of symbols for main parts of the drawings

10: horizontal deflection current generating unit 20: comparator

30: A / D Converter 40: Micom

50: D / A converter D1, D2: diode

H.DY: Horizontal deflection coil Ts: Transformer for detecting deflection current

C1, C2, C3, C4: Capacitor Q1: Horizontal Size Transistor

R1, R2: resistance

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing a horizontal phase automatic adjustment circuit according to the present invention, Figure 2 is a waveform diagram for explaining the operation of the horizontal phase automatic adjustment circuit according to the present invention.

As shown in FIG. 1, an embodiment according to the present invention includes a horizontal deflection current generating unit 10 for generating a horizontal deflection current; A deflection current sensing transformer (Ts) installed between one side of the horizontal deflection coil (H.DY) and the horizontal deflection current generating unit 10 to detect a change in the horizontal deflection current; A first diode (D1) for half-wave rectifying the positive (+) component of the sense current induced in the secondary winding of the deflection current sensing transformer (Ts); A second diode (D2) for half-wave rectifying a negative component of the sensing current induced in the secondary winding of the deflection current sensing transformer (Ts); A first capacitor (C1) smoothing the positive sensed current that is half-wave rectified by the first diode (D1); A second capacitor C2 for removing noise mixed in the positive sensing current smoothed by the first capacitor C1; A third capacitor C3 smoothing the negative sensing current half-wave rectified by the second diode D2; A fourth capacitor C4 for removing noise mixed in the negative sensing current smoothed by the third capacitor C3; The DC voltage level values of the positive sensed (+) sensed current and the negative sensed (−) sensed current removed by the second capacitor C2 and the fourth capacitor C4 are compared to sense the difference. A comparator 20 for outputting a current; An A / D converter 30 for converting a sense current output from the comparator 20 into a digital signal; A microcomputer 40 for outputting a phase correction signal for keeping the phase of the horizontal deflection current constant by stepping down the DC level value of the sensing current indicated by the digital signal output from the A / D converter 30 to 0 (Zero). ) And; And a D / A converter 50 for converting a phase correction signal output from the microcomputer 40 into an analog signal and applying the same to the horizontal deflection current generating unit 10.

The operation of the embodiment according to the present invention configured as described above is as follows.

If the horizontal deflection current output from the horizontal deflection current generating unit 20 in the specific video mode and flowing in the horizontal deflection coil H.DY shows a normal phase, the secondary winding of the transformer Ts for detecting deflection current Ts is normal. As shown in (a) of FIG. 2, the waveform of the sensed current output through is reduced in size compared to the actual horizontal deflection current, but the positive and negative components have the same magnitude. Appears as a waveform of shape.

In addition, the positive polarity (+) component of the sensing current output from the deflection current sensing transformer Ts is half-wave rectified by the first diode D1 for half-wave rectification, and the first capacitor C1 for smoothing and the noise removal are performed. When the noise is smoothed by the second capacitor C2 and input to the comparator 20 through the resistor R1, as shown in (b) of FIG. 3, it appears as a sensing current having a constant positive DC level. And the negative polarity (−) component of the sensing current output from the deflection current sensing transformer Ts is half-wave rectified by the half-wave rectifying second diode D2, and the smoothing third capacitor C3 and the noise removing agent A negative (-) DC having the same size as the positive (+) DC level value shown in (b) of FIG. With sense current with level value appear.

Therefore, when the sense current having the same magnitude of the positive (+) DC level value and the negative (-) DC level value is input to the comparator 20 as described above, the comparator 20 has a DC level value of 0 (Zero). Outputs a sensing current represented by the control signal, and the sensing current represented by the DC level value 0 (zero) is converted into a digital signal by the A / D converter 30 and input to the microcomputer 40. ) Indicates that the DC level represented by the digital signal is 0 (ZERO), so that the phase correction signal for correcting the phase of the horizontal deflection current is not output.

On the other hand, if the horizontal deflection current output from the horizontal deflection current generation unit 20 in the specific video mode and flowing in the horizontal deflection coil H.DY does not exhibit a normal phase, the secondary of the deflection current detecting transformer Ts is secondary. As shown in (a) of FIG. 2, the waveform of the sensed current output through the side winding is reduced in size compared to the actual horizontal deflection current, but the magnitude of the positive (+) component and the negative (-) component is different. Appears as another b-shaped waveform. Here, the b-shaped waveform shown in (a) of FIG. 2 is a sensing current in which the positive (+) component is larger than the negative (-) component.

In addition, the positive polarity (+) component of the sensing current output from the deflection current sensing transformer Ts is half-wave rectified by the first diode D1 for half-wave rectification, and the first capacitor C1 for smoothing and the noise removal are performed. When the noise is smoothed by the second capacitor C2 and input to the comparator 20 through the resistor R1, as shown in (b) of FIG. 3, it appears as a sensing current having a constant positive DC level. And a negative polarity (−) component of the sense current output from the deflection current sensing transformer Ts is half-wave rectified by the second diode D2 for half-wave rectification, and the smoothing third capacitor C3 and the noise removing agent When it is smoothed by the four capacitors C4 and the noise is removed and input to the comparator 20 through the resistor R2, as shown in (c) of FIG.

Therefore, when a sense current having a different magnitude from the positive DC voltage value and the negative DC voltage value is input to the comparator 20, the comparator 20 is configured to generate positive polarity (+) of the sense current. Outputs a sensing current representing a DC level value corresponding to the difference between the DC level value and the negative DC level value, and outputs a difference between the positive and negative DC level values. When a sensing current indicating a corresponding DC level value is converted into a digital signal by the A / D converter 30 and input to the microcomputer 40, the microcomputer 40 sets the DC level value represented by the digital signal to 0 ( ZERO outputs a phase correction signal for voltage drop, and when the phase correction signal is converted into an analog signal by the D / A converter 50 and input to the horizontal deflection current generating unit 10, Phase is automatically corrected so that the secondary of the deflection current sensing transformer Ts Positive (+) component of the sensed current that is output through the winding and the negative (-), the size of the component is displayed in the same manner.

As described above, according to the present invention, if the horizontal deflection current flowing through the horizontal deflection coil (H.DY) of the monitor is detected and the video mode is changed, the horizontal deflection current is automatically adjusted so that it is always kept constant. In order to adjust the phase of the horizontal deflection current, the user does not need to directly operate the monitor for adjusting the horizontal phase of the monitor, and it is not necessary to save the horizontal phase control information according to the video mode in the monitor microcomputer when the monitor is produced. It is effective to shorten the time.

Claims (1)

A horizontal deflection current generating unit 10 generating a horizontal deflection current; A deflection current sensing transformer (Ts) installed between one side of the horizontal deflection coil (H.DY) and the horizontal deflection current generating unit 10 to detect a change in the horizontal deflection current; A first diode (D1) for half-wave rectifying the positive (+) component of the sense current induced in the secondary winding of the deflection current sensing transformer (Ts); A second diode (D2) for half-wave rectifying a negative component of the sensing current induced in the secondary winding of the deflection current sensing transformer (Ts); A first capacitor (C1) smoothing the positive sensed current that is half-wave rectified by the first diode (D1); A second capacitor C2 for removing noise mixed in the positive sensing current smoothed by the first capacitor C1; A third capacitor C3 smoothing the negative sensing current half-wave rectified by the second diode D2; A fourth capacitor C4 for removing noise mixed in the negative sensing current smoothed by the third capacitor C3; The DC voltage level values of the positive sensed (+) sensed current and the negative sensed (−) sensed current removed by the second capacitor C2 and the fourth capacitor C4 are compared to sense the difference. A comparator 20 for outputting a current; An A / D converter 30 for converting a sense current output from the comparator 20 into a digital signal; A microcomputer 40 for outputting a phase correction signal for keeping the phase of the horizontal deflection current constant by stepping down the DC level value of the sensing current indicated by the digital signal output from the A / D converter 30 to 0 (Zero). ) And; Horizontal phase of the multi-mode monitor comprising a D / A converter 50 for converting the phase correction signal output from the microcomputer 40 to an analog signal and applied to the horizontal deflection current generation unit 10 Automatic control circuit.