KR20000001357U - Voltage control circuit using power transformer - Google Patents

Abstract

The present invention relates to a voltage (B +) control circuit using a power transformer for stable horizontal deflection by adjusting the voltage applied to the horizontal output circuit of the monitor from a low frequency to a high frequency, and more specifically, to receive a voltage A power transformer consisting of a secondary side and a tertiary side transformer for outputting a constant voltage irrespective of the frequency of the primary side and the primary side connected to the primary side, and the power transformer according to the frequency output from the microcomputer. Receives a voltage control stage for driving, a horizontal drive transformer stage for driving a horizontal output transistor stage by receiving the voltage regulated by the voltage control stage and output through the power transformer, and receives the current output to the horizontal drive transformer stage It consists of a horizontal deflection stage with horizontal deflection.

Description

Voltage control circuit using power transformer

The present invention relates to a voltage (B +) control circuit of the monitor, more specifically, a voltage (B +) using a power transformer for stable horizontal deflection by adjusting the voltage applied to the horizontal output circuit of the monitor from a low frequency to a high frequency ) Control circuit.

In general, a monitor, a device for displaying data created on a computer by a user, is a representative peripheral device.

In order to display an image on such a monitor, image signals R, G, and B applied from a video card of a computer are input, and horizontal and vertical synchronization signals are received and formed through an electron beam projected on a fluorescent surface of a CRT, a display device. At this time, a circuit for changing the deflection of the electron beam is called a deflection circuit.

Among the deflection circuits, a general configuration of the horizontal deflection circuit is shown in FIG. 1 by using a horizontal oscillation circuit 30 mainly using a blocking oscillation circuit, and using a transistor TR or a field effect transistor FET. A horizontal drive circuit 40 for supplying a base current sufficient to turn on / off an output transistor of the horizontal output circuit 50 by performing two-stage amplification and performing waveform correction, and a sawtooth current through a deflection coil using a switching operation of the transistor. It consists of a horizontal output circuit 50 for generating a.

In addition, a horizontal size control circuit 20 is connected to the horizontal output circuit 50, thereby maintaining a constant size of the horizontal size of the display device at all times.

FIG. 2 is a circuit illustrating the horizontal output circuit in more detail. As shown in FIG. 2, the power applied to the first transformer of the power transformer T is output through the second transformer by the switching operation. The diode D1 and the capacitor are shown in FIG. After rectification by C1, the voltage is applied to the first transistor Q1 and turned on.

Accordingly, a current is induced in the horizontal drive transformer T1 to turn on the second transistor Q2, which is a horizontal output transistor, and a voltage is applied to the horizontal deflection yoke (hereinafter, referred to as DY).

That is, since the B ⁺ voltage of the first transistor Q1 is used only as a power source for inducing the horizontal drive transformer T1, the second transistor Q2 is not sufficiently operated at a specific frequency, thereby turning on / off the power supply. In this case, when the mode is changed or the mode is changed, a transient phenomenon occurs in which the second transistor Q2 or a peripheral part may fail.

The present invention aims to provide a circuit for stable horizontal deflection by supplying sufficient current from a low frequency to a high frequency input to a horizontal output transistor.

1 shows a block diagram of a conventional general conventional horizontal deflection circuit,

2 shows a horizontal deflection circuit according to FIG.

3 is a voltage (B ⁺ ) control circuit using a power transformer according to the present invention.

Hereinafter, with reference to the accompanying drawings, the configuration and operation of the subject innovation in detail as follows.

2 shows a detailed circuit diagram according to an embodiment of the present invention, which is used to output a constant voltage irrespective of the frequency of the primary side for receiving voltage and the reverse side connected to the primary side. A power supply transformer composed of a secondary side and a tertiary side transformer, a voltage adjusting stage for driving the power transformer according to a frequency output from a microcomputer, and a voltage controlled by the voltage adjusting stage and applied with a voltage output through the power transformer A horizontal drive transformer stage for driving an output transistor stage, and a horizontal deflection stage for performing a horizontal deflection by receiving the current output to the horizontal drive transformer stage.

Looking at the operation process according to this configuration in more detail as follows.

First, the power transformer stage 100 receives power through the primary transformer T11 and outputs a high voltage from a low voltage through a secondary transformer T12 or a tertiary transformer T13 connected in reverse phase.

That is, according to the frequency input from the microcomputer 120, the third transistor Q3 and the fourth transistor Q4 configured in the voltage adjusting stage 110 are adjusted in accordance with on / off driving.

In more detail, when the voltage output from the microcomputer 120 and input to the third transistor Q3 of the voltage adjusting stage 110 is low, the third transistor Q3 is turned on at a horizontal frequency. Therefore, the fourth transistor Q4 is turned on.

Accordingly, a low voltage is output from the tertiary side transformer T13 of the power supply stage 100, the low voltage is applied to the diode D1, and the fourth transistor Q4 is turned on. Since it is a state that is) is supplied to the horizontal drive transformer stage 130 through the diode (D2).

On the other hand, when a high voltage is input from the microcomputer 120 and input to the third transistor Q3 of the voltage adjusting stage 110, the fourth transistor Q4 is turned off as the third transistor Q3 is turned off. Off).

Therefore, a high voltage is output through the second transformer T12, rectified by the diodes D3 and D4, and then supplied to the horizontal drive transformer stage 130.

As such, since the low voltage and the high voltage are supplied to the horizontal drive transformer stage, stable current is supplied to the horizontal output transistor Q2, thereby achieving stable horizontal deflection.

As described above, there is an effect of achieving a stable horizontal deflection by supplying a sufficient current to the horizontal output stage from a low voltage to a high voltage.

Claims (2)

A power transformer composed of a primary side for receiving a voltage, a secondary side and a tertiary side transformer for outputting a constant voltage irrespective of a frequency applied by being connected in reverse phase to the primary side; A voltage adjusting stage for driving the power transformer according to the voltage output from the microcomputer; A horizontal drive transformer stage for driving the horizontal output transistor stage by receiving the voltage controlled by the voltage adjusting stage and output through the power transformer; Voltage (B ⁺ ) control circuit using a power supply transformer, characterized in that consisting of a horizontal deflection stage for performing a horizontal deflection by receiving the current output to the horizontal drive transformer stage. The method of claim 1; The voltage regulating stage includes a third transistor for outputting a low voltage, and a fourth transistor for outputting a high voltage. A voltage (B ⁺ ) control circuit using a power transformer.