KR920004381B1 - Horizontal size control circuit for brown tube - Google Patents

Abstract

The adjuster expands the horizontal size of a CRT without limit. The adjuster comprises a horizontal deflection signal amplifier (10), a horizontal deflection coil (20), a deflection signal detector (30) for detecting the output signal of the amplifier (10), a rectifier (40) for rectifying the output signal of the deflection signal detector (30), an attenuator (50) for attenuating the output signal of the rectifier (40), a comparator (60) for comparing the output signal of the attenuator to reference signal, a reference signal generator (70) for generating reference signal, a voltage amplifier (80) for amplifying the voltage magnitude of the output signal of the comparator, and a current amplifier (90) for amplifying the current magnitude of the output signal of the amplifier (8) to control the power applied to the amplifier (10).

Description

CRT Horizontal Size Control Circuit

1 is a detailed circuit diagram of the present invention.

* Explanation of symbols for main parts of the drawings

10: horizontal deflection output unit 20: deflection unit

30: deflection power detector 40: rectifier

50: attenuation unit 60: comparison unit

70: reference setting unit 80: voltage amplifier

90: current amplifier

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a circuit around a cathode ray tube (CRT) for controlling an image size, and more particularly to a circuit for adjusting the size of a horizontal size.

In the prior art, the horizontal amplitude was adjusted by changing the value of the variable coil in the horizontal deflection.

That is, as the variable coil value increases, the current flowing in the horizontal deflection coil HDY decreases, so that the horizontal amplitude is small. On the contrary, when the variable coil value decreases, the current flowing in the horizontal deflection coil H-DY increases and the horizontal amplitude increases. Another conventional method is to adjust the horizontal amplitude by changing the capacitor to switch to change the current in the deflection coil. However, in the case of the variable coil LI, a variable bobbin may be impossible to adjust due to internal heat after a long time, and in the method of selecting a cache pattern in a switchable manner, it is unreasonable to the basic circuit due to a momentary surge current during switching. Since energy is supplied, it is a cause of failure of the circuit, and since the values of the variable coil LI and the capacitor are limited, the horizontal amplitude cannot be infinitely changed.

It is therefore an object of the present invention to provide a circuit that can circumvent limitations in the influence of ambient temperature and in the variation of horizontal amplitude.

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

1 is a specific circuit diagram of the present invention, a horizontal output unit 10 for receiving and amplifying and outputting the output of a horizontal drive stage, and a deflection for deflecting the horizontal side of the CRT by inputting the output power of the horizontal output unit 10. A deflection signal detector 30 for detecting the same signal as the output signal of the horizontal output unit 10, a rectifier 40 for rectifying and smoothing the detected output signal of the deflection signal detector; An attenuator 50 for variably attenuating the output signal of the rectifier 40, a comparator 60 for comparing the output signal of the attenuator 50 with a predetermined reference value, and a reference part for generating the predetermined reference value 70 and a current amplifying the output of the voltage amplifier 80 and the voltage amplifier 80 to voltage-amplify the output of the comparator 60 to control the power of the horizontal output unit 10. It consists of an amplifier 90.

The horizontal output unit 10 includes an amplifying transistor Q1, a damping diode D1, and a capacitor C1-C2, and the deflection unit 20 includes a horizontal deflection coil H-DY. The deflection signal detector 30 includes a capacitor C3 and a transformer T1, and the rectifier 40 includes diodes D2 and D5 and a smoothing capacitor C4, a capacitor C9, a load resistor R1, and Comprising resistors R13 and R14, attenuator 50 is composed of " T " type resistance attenuators R2, R3, R4 and variable resistor VR1, and comparator 60 is resistors R5, R6. , R12, and capacitors C5 and C8, a diode D3, and an op amp OP1, and the reference setting unit 70 includes a zener diode ZD1 and a resistor R7. The voltage amplifier 80 includes a voltage amplifier Q2, a bias resistor R8, and an emitter stabilizer R9. The current amplifier 90 includes a base resistor R10 and an amplifying drive transistor Q3. And a current amplifier transistor Q4, a transistor protection diode D4, and a current cut-off resistor R11.

Hereinafter, a specific embodiment of the present invention to realize the object of the above configuration will be described. In FIG. 1, when the horizontal B + voltage is supplied to the primary coil of the transformer T1 of the deflection power detector through the resistor R11 of the current amplifier 90, the amplification transistor Q1 of the horizontal deflection output part is Is turned on. Accordingly, the organic power in proportion to the B + voltage is generated at the secondary T1. The organic power is smoothed by the smoothing capacitor C4 rectified by the diode D2 of the rectifier 40 and output through the load resistor R1.

The signal output through the load resistor R1 of the rectifier 40 is attenuated by changing the values of the T-type attenuator and variable resistor VR1 of the attenuator 50. The output of the attenuator 50 is supplied to the negative input terminal of the op amp OP1 of the comparator 60 and compared with a predetermined reference value supplied to the positive input terminal. Is output by the off-amp OP1.

The predetermined reference value of the off amplifier OP1 is determined by the value of the zener diode ZD1 of the reference setting unit 70 and is supplied to the positive input terminal of the op amp OP1. The signal output from the comparator 60 is applied as a bias voltage of the voltage amplifier transistor Q2 of the voltage amplifier 80 to determine and output a collector current of the voltage amplifier transistor Q2. The output signal of the voltage amplifying part is applied to the base of the amplifying drive transistor Q3 of the current amplifying part 90 through a base resistor R16 to determine the bias of the amplifying drive transistor Q3 and at the same time the current amplifying transistor. The bias of Q4 is determined to determine the collector current of the current amplifier transistor Q4.

That is, when the bias voltage of the amplifying drive transistor is small, the collector current of the current amplifying transistor Q4 is small. On the contrary, when the bias of the amplifying drive transistor Q3 is large, the collector current of the current amplifying transistor Q4 is large and the transistor T1 is increased. ) And the voltage at node D, which is the connection point of the collector of current amplifying means Q4. Therefore, the current flowing in the horizontal deflection coil can be adjusted.

In addition, even though the amplifying transistor Q1 malfunctions due to external noise input to the horizontal deflection output unit 10 and the current decreases in the horizontal deflection coil H-DY, the deflection current detection unit 10 receives the current. By detecting and repeatedly performing the operation from the rectifier 40 to the rectifier amplifier 90, the current flows through the original horizontal deflection coil H-DY, and the variable resistor of the controller 50 can be recovered. If the VR1 is adjusted, the operation from the comparator 60 to the current amplifier 90 is repeated so that the horizontal size can be arbitrarily changed by adjusting the current flowing through the horizontal deflection coil H-DY. Can be.

By adjusting the current, the horizontal size can be arbitrarily changed.

Therefore, as can be seen through the above embodiment, the horizontal size can be infinitely expanded as compared to the method of varying the horizontal size by varying the conventional coil or by switching the condenser in a conventional manner. There is an advantage to protect the basic circuit from the danger of sudden surge current.

Claims (2)

In the CRT horizontal deflection circuit, a horizontal output unit 10 for receiving and amplifying and outputting the output of the horizontal drive stage, and a deflection unit for deflecting the horizontal direction of the CRT by inputting the output power of the horizontal output unit 10 ( 20), a deflection signal detection unit 30 for detecting the same signal as the output signal of the horizontal output unit 10, a rectifying unit 40 for rectifying and smoothing the signal output from the detection of the deflection signal detection unit 30, An attenuator 50 for variably attenuating the output signal of the rectifier 40, a comparator 60 for comparing the output signal of the attenuator 50 with a predetermined reference value and outputting a comparison value; The reference unit 70 generating a reference value, the voltage amplifier 80 for voltage amplifying the output of the comparator 60, and the current amplified output of the voltage amplifier 80 to the horizontal output unit 10 Circuit comprising a current amplifier for controlling the power supply (90). The horizontal output unit 10 includes an amplifying transistor Q1, a damping diode D1, and a capacitor C1-C2, and the deflection unit 20 includes a horizontal deflection coil H-. DY), the deflection signal detector 30 includes a capacitor C3 and a transistor T1, and the rectifier 40 includes diodes D2 and D5 and smoothing capacitors C4 and C9 and a load. The resistor R1 and the resistors R13 and R14 are configured, the attenuation unit 50 is composed of "T" type resistance attenuators R2, R3 and R4 and the variable resistor VR1, and the comparison unit 60 is Resistor R5, R6, R12, capacitor C5-C8, diode D3, and op amp OP1, and the reference setting unit 70 is composed of control diode ZD1 and resistor R7. The voltage amplifier 80 includes an emitter stability resistor R9 and a bias resistor R8, and the current amplifier 90 includes a base resistor R10, an amplification drive transistor Q3, and a current amplifier transistor ( Q4) and transistor protection A horizontal deflection circuit, characterized by consisting of a Eau (D4) and the current blocking resistance (R11).

Images