KR0155592B1 - Horizontal size correction circuit - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

monitor

2. The technical problem to be solved by the invention

Adjust the horizontal size of the monitor

3. Summary of the Solution of the Invention

When adjusting the horizontal size on the monitor, adjust the horizontal size to maintain the same size at all times according to the change in the flyback transformer voltage.

To this end, when the flyback transformer voltage is input, the flyback transformer voltage is detected to generate a control signal corresponding to the variation level. The peak voltage of the voltage outputting the flyback transformer is detected.

After that, when the level of the control signal is large, the path of the peak voltage is largely adjusted to make the horizontal size small. When the level of the control signal is small, the level of the peak voltage is adjusted small to make the horizontal size large. do.

4. Important uses of the invention

Maintain horizontal size on the monitor regardless of load fluctuation.

Description

Horizontal size correction circuit and method according to load

1 is a circuit diagram for controlling a horizontal size in a conventional monitor.

2 is a circuit diagram for correcting the horizontal size to the change of the load in the monitor according to the invention.

* Explanation of symbols for main parts of the drawings

R1-R10: Resistor C1-C7: Capacitor

OP1-OP2: Operational Amplifier D1-D2: Diode

VR1: Variable resistor L1-l4: Coil

The present invention relates to a circuit and a method for correcting the horizontal size of the monitor, and more particularly to a circuit and a method that can automatically correct the horizontal size in accordance with the load.

In general, the flyback transformer of a monitor performs a function of deflecting a horizontal position and a vertical position of a displayed screen. Looking at the generation process of the voltage supplied to the flyback transformer in the monitor as described above, the signal waveform is determined by determining the frequency according to the signal.

The voltage discrimination signal according to the load and the waveform-formed signal are differentially amplified to form a pulse according to frequency conversion, and then converted into a DC voltage to generate a supply voltage of the flyback transformer.

The flyback transformer supply voltage generated as described above is applied to the flyback transformer, and this voltage is greatly changed in accordance with the load. That is, it appears as a change in high voltage according to the load, and the change is caused by the difference in the horizontal size.

1 shows the configuration of a circuit for controlling the horizontal size in a conventional monitor. Referring to FIG. 1, the flyback transformer voltage FBTV is applied to the first node N1. A flyback transformer L4 and a horizontal DY L3 are connected in series between the first node N1 and the second node N2.

A linear damping resistor R4 and a linear damping capacitor C5 are connected in series to the second node N2, and a linear coil L2 (linearity coil) is connected in parallel, and a capacitor C5 and a coil L2 are connected in common. The other end of the capacitor C4 is connected to the third node N3.

In addition, the capacitor C2 and the diode D1 are connected in parallel between the second node N2 and the third node N3, and the capacitor C3 and the diode D2 are connected in parallel between the third node N3 and the ground terminal. A coil L1 is connected in series with the third node N3, and a smoothing capacitor C1 is connected between the other end of the coil L1 and the ground terminal. The other end of the coil L1 is also connected to the emitter of transistor Q2 of the Darlington connection, and the base end of the transistor Q2 is connected to the emitter terminal of transistor Q1.

The collector terminal of the transistor Q1 is connected to the ground terminal through a current limiting resistor R3, and the base terminal is connected to the variable resistor VR1. The voltage distribution resistor R1, the variable resistor VR1, and the resistor R2 are connected in series between the power supply voltage and the ground terminal.

In the conventional horizontal size control circuit having the above configuration, as described above, since the flyback trans voltage FBTV applied to the first node N1 is changed depending on the load at the same frequency, the peak-to-peak generated at the third node N3 ( peak to peak) voltage will vary.

That is, if the flyback trans voltage FBTV applied to the first node N1 is high, the peak-to-peak voltage generated at the third node N3 becomes high, and if the flyback trans voltage FBTV applied to the first node N is low, The peak-to-peak voltage generated at the third node N is lowered.

The AC voltage generated at the third node N3 is rectified to the DC voltage by the horizontal choke coil L1 and the smoothing capacitor C1, and the DC voltage is applied to the emitter terminal of the transistor Q2.

That is, the voltage of the DC component that changes according to the load is generated at the emitter terminal of the transistor Q2. At this time, the voltage applied to the bass stage of the transistor Q1 of the Darlington connection is fixed at a predetermined level by voltage divided by the resistor R1, the variable resistor VR1 and the resistor R2. However, since the voltage applied to the emitter terminal of the transistor Q2 varies depending on the load, it has a voltage difference.

Therefore, when the load is large, since a high voltage is applied to the emitter terminal of the transistor Q2, the transistor Q1 and the transistor Q2 conduct and flow a lot of current, thereby increasing the horizontal size.

On the contrary, when the load is small, since a low voltage is applied to the emitter terminal of the transistor Q2, the transistor Q1 and the transistor Q2 conduct a small amount of current and allow a small current to flow, thereby reducing the horizontal size.

Therefore, even when the fixed voltage is generated at the base terminal of the transistor Q1 to maintain the horizontal size, the horizontal size is not desired as described above when the flyback transformer voltage FBTV is input in response to a load. It can be seen that the variable.

Accordingly, an object of the present invention is to provide a circuit and a method capable of maintaining a horizontal size at a constant size regardless of a load change in a circuit for controlling the horizontal size of a monitor.

Another object of the present invention is to provide a circuit and a method for adaptively correcting a horizontal size in a monitor in response to a change in load.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the same parts in the figures represent the same reference signs wherever possible.

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

2 is a configuration diagram of a horizontal size correction circuit of a monitor according to the present invention, in which a flyback transformer voltage FBTV is applied to a first node N1. A flyback transformer L4 and a horizontal DY L3 are connected in series between the first node N1 and the second node N2.

A linear damping resistor R4 and a linear damping capacitor C5 are connected in series to the second node N2, and a linear coil L2 (linearity coil) is connected in parallel, and a capacitor C5 and a coil L2 are connected in common. The other end of the capacitor C4 is connected to the third node third.

In addition, the capacitor C2 and the diode D1 are connected in parallel between the second node N2 and the third node N3, and the capacitor C3 and the diode D2 are connected in parallel between the third node N3 and the ground terminal. The above configuration becomes a means for detecting the peak voltage.

A coil L1 is connected in series with the third node N3, and a smoothing capacitor C1 is connected between the other end of the coil L1 and the ground terminal. The other end of the coil L1 is also connected to the emitter of transistor Q2 of Darlington connection, and the bass end of transistor Q2 is connected to the emitter end of transistor Q1.

The collector terminal of the transistor Q1 is connected to the ground terminal through the current limiting resistor R3, and the base terminal is connected to the fourth node N4. The configuration is a means for adjusting the horizontal size.

The voltage distribution resistor R1, the variable resistor VR1, and the resistor R2 are connected in series between the power supply voltage and the ground terminal, and the volume control terminal of the variable resistor VR1 is connected to the fourth node N4. The configuration is a means for generating the first control signal.

A capacitor C7 and a resistor R9 are connected in parallel to the first node N, and a resistor R8 connected in common with the capacitor C7 and the resistor R9 is connected to the other end of the ground terminal. In addition, the operational amplifier OP2 having the non-inverting terminal commonly connected to the capacitor C7 and the resistor R9 and the inverting terminal connected to the output terminal has a buffer form.

Resistor R7 and resistor R7 connected in series between the supply voltage and the ground terminal generate a reference voltage. The operational amplifier OP1 has a non-inverting terminal connected to the output terminal of the operational amplifier OP2, an inverting terminal connected to the reference voltage, and an output terminal connected to the fourth node N4.

A resistor R5 and a capacitor C6 are connected in parallel between the non-inverting terminal and the output terminal of the operational amplifier OP1. The configuration is a means for generating a second control signal.

Referring to the operation of the present invention in detail based on the above configuration, the flyback transformer voltage FBTV is applied to the first node N1 through the resistor R10. The flyback transformer voltage FBTV applied to the first node N1 is supplied to the flyback transformer L4 as described above to operate as described above.

In addition, the flyback transformer voltage FBTV applied to the first node N is divided through the surge protection capacitor C7, the resistor R9 and the resistor R8, and then applied to the non-inverting terminal of the operational amplifier OP2 having the buffer configuration. Therefore, the flyback transformer voltage FBTV outputting the operational amplifier OP2 is divided by the voltage according to the variation.

The flyback transformer voltage FBTV outputting the operational amplifier OP2 is applied to the non-inverting terminal of the operational amplifier OP1. The operational amplifier OP1 is offset adjusted to the reference voltage set by the resistors R6 and R7, and is applied to the resistors R4 and the capacitor C6. The amplification degree is determined and output.

Therefore, the signal outputting the operational amplifier OP1 is represented by the value of the flyback transformer voltage FBTV according to the load variation.

Since the output of the operational amplifier OP1 is applied to the fourth node N4, the transistors Q1 and Q2 adjust the horizontal size according to the variation of the flyback transformer voltage FBTV applied to the fourth node N4.

Therefore, when the flyback transformer voltage FBTV is increased or decreased due to the load variation, one side is supplied with the supply voltage of the flyback transformer L4 and the other side is applied as a control signal for adjusting it.

Therefore, when the load is large, the flyback transformer voltage FBTV applied to the non-inverting terminal of the operational amplifier OP1 is sensed as a voltage corresponding to the variation of the load. Therefore, the operational amplifier OP1 amplifies the sensed voltage and converts the high voltage into the fourth voltage. It is applied to the node N4.

As a result, the bias voltage applied to the base terminal of the transistor Q1 increases. Therefore, the current discharged from the capacitor C1 becomes smaller because the amount of current flowing from the emitter of the transistor Q1 to the collector through the emitter stage of the transistor Q2 becomes smaller, and thus a voltage higher than the set voltage is applied. As a result, the horizontal size of the image displayed on the screen is reduced.

On the contrary, when the load decreases, the flyback transformer voltage FBTV applied to the non-inverting terminal of the operational amplifier OP1 is also lowered, so that the operational amplifier OP1 applies a low voltage to the fourth node N4. Then, since a low voltage is applied to the base end of the transistor Q1, the amount of current flowing from the emitter to the collector increases, so that the transistor Q1 becomes largely conductive. Therefore, the current flowing through the transistor Q1 increases, so that the horizontal size increases.

Therefore, by detecting the flyback transformer voltage FBTV, it is possible to detect the change in load, and if the load fluctuates large, the horizontal size is adjusted small, and if the load fluctuates small, the horizontal scale is large and irrelevant to the load variation. In this way, the horizontal size of the monitor can be constantly maintained.

Claims (8)

A horizontal size correction circuit of a monitor, comprising: a flyback transformer connected to an input node of a flyback transformer voltage, and connected between the voltage input node and a control node, and detecting a voltage difference according to a load variation of the flyback transformer voltage. Means for generating a control signal, and connected between the flyback transformer and the control node, and means for adjusting the amount of current by controlling the amount of current by the control signal, so that the horizontal size is increased when the flyback voltage is increased. And correcting a smaller value and a larger horizontal size at which the flyback transformer voltage can be lowered. 2. The apparatus of claim 1, wherein the means for generating the control signal is connected to the voltage input node, means for dividing the flyback transformer voltage to detect a voltage change, means for generating a reference voltage, and the sensed voltage. And a means for amplifying a difference between a reference voltage and a reference voltage to generate a control signal. The apparatus of claim 1, wherein the means for adjusting the horizontal size is connected to the flyback transformer and generates a peak voltage for outputting the flyback transformer, receives the peak voltage, and applies the control voltage to the control node. And a means for adjusting the horizontal size by switching the control signal to form a current path of the peak voltage. A horizontal size correction circuit of a monitor, comprising: a flyback transformer connected between a first node and a second node for inputting a flyback transformer voltage, and connected between the first node and a fourth node, and the flyback transformer Means for detecting a voltage difference according to a change in voltage and outputting it as a control signal to the fourth node, and detecting a peak voltage of a voltage connected between the second node and a third node and outputting the flyback transformer. Means and connected between the third node and the fourth node, and means for adjusting a horizontal size by adjusting a passage of the peak voltage according to the control signal, wherein the horizontal size is increased when the flyback voltage is increased. And a small correction and a large correction of the horizontal size when the flyback transformer voltage is lowered. 5. The apparatus of claim 4, wherein the means for generating the control signal is connected to the first node, means for dividing the flyback transformer voltage to detect a voltage change, means for generating a reference voltage, and the sensed voltage. And a means for amplifying a difference between a reference voltage and a reference voltage to generate a control signal. The control signal according to claim 4, wherein the means for adjusting the horizontal size is connected to the third node to convert the peak voltage into a direct current voltage, and a control signal applied to the control node as a switching element in Darlington. And a means for adjusting the horizontal size by switching by means of forming a current path of the peak voltage. A method of correcting a horizontal size of a monitor, the method comprising: inputting a flyback transformer voltage, detecting a flyback transformer voltage to generate a control signal corresponding to a variation level, and outputting the flyback transformer; Detecting the peak voltage of the voltage; correcting the horizontal size by adjusting the path of the peak voltage large when the level of the control signal is large; and reducing the path of the peak voltage when the control signal level is small. Horizontal size correction circuit, characterized in that the process consists of a process for largely correcting the horizontal size. The method of claim 7, wherein the generating of the control signal comprises: dividing the flyback transformer voltage to detect a voltage change, and amplifying the difference between the detected voltage and the high reference voltage to generate the control signal. Horizontal size correction circuit, characterized in that.