KR19990028838U - High voltage generation circuit of high pressure separate monitor - Google Patents

Abstract

The present invention relates to a high pressure generating circuit of the high pressure detachable monitor.

The present invention is a capacitor (C1) and the high-pressure sensing voltage output from the high-voltage B + voltage sensing winding (Ls) of the phase tuning unit 100 for sensing the high voltage B + voltage applied to the primary winding of the flyback transformer 50 and The derivative is converted into a phase tuning signal by differentiation by the resistor R1, and then the triangular wave output from the triangular wave generator 20 is applied to the signal line input to the horizontal deflection PWM controller 70, so that the high voltage PWM controller 30 and The phase difference of the triangular waves input to the horizontal deflection PWM controller 70 is always kept constant in a range such that the electromagnetic waves emitted from the water pipe can be attenuated below a prescribed value.

Description

Circuit for generating High Voltage in a monitor being separated high voltage section from horizontal deflection section

The present invention relates to a high pressure generating circuit of the high pressure detachable monitor.

In general, the high-voltage separate monitor separates the primary winding of the horizontal deflection unit and the flyback transformer (FBT) and at the same time by using a separately installed switching means, a high voltage B + voltage that is always supplied at a predetermined level to the primary winding of the flyback transformer. A monitor having a high voltage generating circuit configured to generate an anode high voltage (HV) of a water pipe by intermittent control, wherein the flyback is configured as the video mode changes in a monitor in which the horizontal deflection portion and the flyback transformer are integrated. When the high voltage B + voltage and the anode high voltage induced in the primary winding of the transformer are varied together, the anode current of the water pipe is changed, and the vertical / horizontal size and brightness of the screen are abnormally solved.

In the high-voltage separation type monitor as described above, various voltages required for the water pipe are provided from the high-voltage generator circuit as shown in FIG. 1, and the high-voltage generator circuit includes a horizontal oscillator 10, a triangular wave generator 20, and a high voltage. PWM controller 30, first buffer 31, high voltage DC / DC converter 40, flyback transformer 50, high voltage switching unit 60, horizontal deflection PWM controller 70, second buffer 71, a horizontal deflection DC / DC converter 80, and a horizontal deflection portion 90. As shown in FIG.

Here, the triangular wave generator 20 outputs a triangular wave synchronized with the horizontal drive signal output from the horizontal oscillator 10 for outputting a horizontal drive signal corresponding to a specific video mode whenever the video mode is changed. When the triangular wave output from the triangular wave generator 20 is input to the high voltage PWM controller 30 and the horizontal deflection PWM controller 70, the high voltage PWM controller 30 and the horizontal deflection PWM controller 70 may be used. Switching pulses for generating a high voltage B + voltage and a scan B + voltage by switching the driving voltage Vin input to the high voltage DC / DC converter 40 and the horizontal deflection DC / DC converter 80, respectively. Output the signal.

Therefore, the switching pulse signal output from the high voltage PWM controller 30 and the horizontal deflection PWM controller 70 is buffered by the first buffer 31 and the second buffer 71, respectively. When the DC / DC converter 40 and the horizontal deflection DC / DC converter 80 are inputted, the high pressure DC / DC converter 40 and the horizontal deflection DC / DC converter 80 are respectively used for high pressure. The B + voltage and the scan B + voltage are generated and input to the flyback transformer 50 and the horizontal deflection unit 90. At this time, the high voltage B + voltage applied to the primary winding of the flyback transformer 50 is the anode high voltage (induced by the secondary winding of the flyback transformer 50 as the high voltage switching unit 60 performs a switching operation). HV), and the scan B + voltage input to the horizontal deflection unit 90 is applied to the horizontal deflection coil H.DY.

However, the high-voltage generating circuit of the high-voltage separation type monitor as described above is output from the triangular wave generator 20 and the phases of the triangular waves input to the high-voltage PWM controller 30 and the horizontal deflection PWM controller 70 are mutually different. Not only does it coincide, but the phase difference of the triangular wave is increased each time the video mode is changed, there is a disadvantage that the harmful electromagnetic waves emitted from the receiving tube increases. That is, the high-voltage separation type monitor has a negative (-) pulse which is induced from the flyback transformer 50 by the positive (+) electromagnetic wave mainly generated by the horizontal deflection current flowing through the horizontal deflection coil of the horizontal deflection unit 90. Since the phase difference of the triangular wave input to the high voltage PWM controller 30 and the horizontal deflection PWM controller 70 increases, the phase difference between the positive electromagnetic wave and the negative pulse increases. There is a problem that it is difficult to attenuate the electromagnetic wave emitted from the water pipe below the prescribed value.

In order to solve the above problem, the present invention has a phase difference of the triangular wave output from the triangular wave generator and input to the high voltage PWM controller and the horizontal deflection PWM controller, respectively, to be less than the prescribed value. It is an object of the present invention to provide a high-voltage generating circuit of a high-voltage separation type monitor that is always kept constant in a range that can be attenuated.

The present invention devised to achieve the above object comprises: a horizontal oscillator for outputting a horizontal drive signal corresponding to a specific video mode whenever the video mode is changed; A triangular wave generator for outputting a triangular wave synchronized with a horizontal drive signal output from the horizontal oscillator; A high voltage PWM controller for outputting a switching pulse signal for generating a high voltage B + voltage when the triangle wave output from the triangle wave generator is input; A horizontal deflection PWM controller for outputting a switching pulse signal for generating a scan B + voltage when the triangle wave output from the triangle wave generator is input; A high voltage DC / DC converter for switching a driving voltage Vin to output a high voltage B + voltage to be applied to a primary winding of a flyback transformer when a switching pulse signal output from the high voltage PWM controller is input; A horizontal deflection DC / DC converter for switching the driving voltage Vin to output a scan B + voltage and applying the voltage to the horizontal deflection unit when a switching pulse signal output from the horizontal deflection PWM controller is input; A high voltage switching unit for switching the high voltage B + voltage applied to the primary winding of the flyback transformer to induce an anode high voltage (H.V) to the secondary winding of the flyback transformer; The high-voltage sensing voltage output from the high-voltage B + voltage sensing winding for sensing the high voltage B + voltage applied to the primary winding of the flyback transformer is output from the triangular wave generator by differentiating using a differential circuit composed of a capacitor and a resistor. And a phase tuning unit for outputting a phase tuning signal for maintaining a constant phase difference of the triangular wave input to each of the high voltage PWM controller and the horizontal deflection PWM controller.

The circuit of the present invention configured as described above, the high-voltage sensing voltage output from the high-voltage B + voltage sensing winding of the phase tuning unit for sensing the high voltage B + voltage applied to the primary winding of the flyback transformer by the capacitor and the resistor. After converting into a phase tuning signal by differentiating, the triangular wave output from the triangular wave generating unit is applied to the signal line input to the horizontal deflection PWM controller, so that the triangular wave is input to the high voltage PWM controller and the horizontal deflection PWM controller, respectively. The phase difference is always kept constant in a range such that the electromagnetic waves emitted from the water pipe can be attenuated below a specified value.

1 is a view showing a high pressure generating circuit of a general high pressure detachable monitor;

2 is a view showing a high-pressure generating circuit of the high-voltage separation monitor according to the present invention,

3 is a waveform diagram illustrating the operation of the high voltage generation circuit shown in FIG. 2.

Explanation of symbols on the main parts of the drawings

10: horizontal oscillation unit 20: triangle wave generator

30: high pressure PWM controller 31: first buffer

40: high voltage DC / DC converter 50: flyback transformer

60: high pressure switching unit 70: horizontal deflection PWM controller

71: second buffer 80: DC / DC converter for horizontal deflection

90: horizontal deflection portion 100: phase tuning portion

C1: capacitor R1: resistor

Ls: High voltage B + voltage sensing winding

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

2 is a view showing a high-voltage generating circuit of the high-voltage separation monitor according to the present invention, Figure 3 is a waveform diagram for explaining the operation of the high-voltage generating circuit shown in FIG.

As shown in FIG. 2, an embodiment according to the present invention includes a horizontal oscillator 10 for outputting a horizontal driving signal corresponding to a specific video mode whenever a video mode is changed; A triangular wave generator 20 for outputting a triangular wave synchronized with a horizontal drive signal output from the horizontal oscillator 10; A high voltage PWM controller 30 outputting a switching pulse signal for generating a high voltage B + voltage when the triangle wave output from the triangle wave generator 20 is input; A horizontal deflection PWM controller 70 for outputting a switching pulse signal for generating a scan B + voltage when the triangular wave output from the triangular wave generator 20 is input; When the switching pulse signal output from the high voltage PWM controller 30 is input, the high voltage DC / DC converter for switching the driving voltage Vin to output the high voltage B + voltage and applying it to the primary winding of the flyback transformer 50. 40; When the switching pulse signal output from the horizontal deflection PWM controller 70 is input, a horizontal deflection DC / DC converter for switching the driving voltage Vin to output the scan B + voltage and applying it to the horizontal deflection unit 90 ( 80); A high pressure switching unit 60 for switching the high voltage B + voltage applied to the primary winding of the flyback transformer 50 to induce an anode high voltage (H.V) to the secondary winding of the flyback transformer 50; A differential circuit consisting of a capacitor (C1) and a resistor (R1) is a high voltage sensing voltage output from the high voltage B + voltage sensing winding (Ls) for sensing the high voltage B + voltage applied to the primary winding of the flyback transformer (50). The phase tuning signal is outputted from the triangular wave generating unit 20 by differentiation to maintain a constant phase difference between the triangular waves respectively input to the high voltage PWM controller 30 and the horizontal deflection PWM controller 70. It comprises a phase tuning unit 100 to output.

Referring to the operation of the embodiment according to the present invention configured as described above are as follows.

The horizontal oscillator 10 shown in Figure 2, the triangular wave generator 20, the high-voltage PWM controller 30, the first buffer 31, the high-voltage DC / DC converter 40, the Flyback transformer 50, the high voltage switching unit 60, the horizontal deflection PWM controller 70, the second buffer 71, the horizontal deflection DC / DC converter 80, and the horizontal deflection The operation of 90 is the same as that of the prior art, so detailed description thereof is omitted.

If the waveform of the horizontal drive signal output from the horizontal oscillator 10 appears as shown in FIG. 3A, the waveform of the triangular wave output from the triangular wave oscillator 20 is shown in FIG. This triangular wave is branched at the point A shown in FIG. 2 and input to the high voltage PWM controller 30 and the horizontal deflection PWM controller 90. The horizontal deflection PWM controller 90 outputs a switching pulse signal, and the high voltage DC / DC converter 40 generates a high voltage B + voltage to be applied to the primary winding of the flyback transformer 50. The horizontal deflection DC / DC converter 80 generates the scan B + voltage and applies it to the horizontal deflection unit 90.

Subsequently, when the B + voltage sensing winding Ls in the phase tuning unit 100 senses the B + voltage applied to the primary winding of the flyback transformer 50 and outputs a high voltage sensing voltage, the high voltage sensing voltage is output. 3 is a waveform as shown in (c) of FIG. 3, and the high voltage sensed voltage output from the B + voltage sense winding Ls is differentiated by the capacitor C1 and the resistor R1 and converted into a phase tuning signal. When the waveform as shown in (d) of Figure 3 appears at point B of FIG.

Therefore, when the waveform shown in (d) of FIG. 3 is applied to point C of FIG. 2, the triangular wave finally output from the triangular wave generator 20 and applied to the horizontal deflection PWM controller 70 is shown in FIG. As shown in (e) of FIG. 3, the waveform shown in FIG. 3 (a) maintains a constant phase difference, and the phase difference is determined by the time constants of the capacitor C1 and the resistor R1. It is decided. In other words, the time constant may be adjusted to keep the electromagnetic wave emitted from the water pipe at all times constant in a range sufficient to attenuate below a prescribed value.

As described above, according to the present invention, the phase difference of the triangular wave output from the triangular wave generator and input to the high voltage PWM controller and the horizontal deflection PWM controller may be attenuated below the specified value. If it is kept constant in the range as much as possible, there exists an effect which can attenuate the electromagnetic wave emitted from the front surface of a water pipe below a predetermined value.

Claims (1)

A horizontal oscillator 10 for outputting a horizontal driving signal corresponding to a specific video mode whenever the video mode is changed; A triangular wave generator 20 for outputting a triangular wave synchronized with a horizontal drive signal output from the horizontal oscillator 10; A high voltage PWM controller 30 outputting a switching pulse signal for generating a high voltage B + voltage when the triangle wave output from the triangle wave generator 20 is input; A horizontal deflection PWM controller 70 outputting a switching pulse signal for generating a scan B + voltage when the triangle wave output from the triangle wave generator 20 is input; When the switching pulse signal output from the high voltage PWM controller 30 is input, the high voltage DC / DC converter for switching the driving voltage Vin to output the high voltage B + voltage and applying it to the primary winding of the flyback transformer 50. 40; When the switching pulse signal output from the horizontal deflection PWM controller 70 is input, a horizontal deflection DC / DC converter for switching the driving voltage Vin to output the scan B + voltage and applying it to the horizontal deflection unit 90 ( 80); A high pressure switching unit 60 for switching the high voltage B + voltage applied to the primary winding of the flyback transformer 50 to induce an anode high voltage (H.V) to the secondary winding of the flyback transformer 50; A differential circuit consisting of a capacitor (C1) and a resistor (R1) is a high voltage sensing voltage output from the high voltage B + voltage sensing winding (Ls) for sensing the high voltage B + voltage applied to the primary winding of the flyback transformer (50). The phase tuning signal is outputted from the triangular wave generating unit 20 by differentiation to maintain a constant phase difference between the triangular waves respectively input to the high voltage PWM controller 30 and the horizontal deflection PWM controller 70. High pressure generation circuit of the high-voltage separation type monitor, characterized in that it comprises a phase tuning unit 100 for outputting.