KR880000992B1 - Monitor for a computer - Google Patents

Abstract

This invention relates to a computer monitor which can be operated by both the composite signal mode and the TTL signal mode. By the selection of composite amplification circuit (2) and TTL imaging signal drive circuit (20), the first switch terminal (6) is connected between them in order to be connected to the imaging signal output circuit (5). By the selection of the horizontal oscillation circuit and TTL vertical signal drive circuit (21), the second switch terminal (17) is connected between them so as to be connected to the vertical oscillation output circuit (7). The third switch terminal (18) is connected between (6) and (22) in the same manner.

Description

Computer monitor

1 is a block diagram of a computer monitor of a conventional composite signal system.

2 is a block diagram of a conventional TTL signal type computer monitor.

3 is a block diagram of a computer monitor of the present invention which can be operated in combination in a composite signal method and a TTL signal method of a conventional computer.

4 is a detailed view of one embodiment of the present invention shown in FIG.

5 is a signal waveform diagram of an embodiment of the present invention.

6 (a) to 6 (c) are peripheral correction circuits of a computer monitor applied to an embodiment of the present invention, where (a) is a horizontal shift circuit, (b) is a vertical shift circuit, and (c) Is an FBT circuit diagram.

* Explanation of symbols for main parts of the drawings

2: composite signal amplification circuit 3: synchronous separation circuit

4: pedestal clamp circuit 5: video signal output circuit

6: horizontal oscillation and drive circuit 7: vertical oscillation and output circuit

8: horizontal output circuit 9: blanking circuit

10: FBT 11: CRT

12: power supply circuit 16: the first switch

17: second switch 18: third switch

19: fourth switch 26: fifth switch

25: circuit select switch 23: horizontal shift circuit

24: vertical shift circuit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a computer monitor, and more particularly, to a computer monitor capable of operating in both a composite signal mode and a TTL signal (Transistor Transistor Logic Signal mode) of a conventional computer.

Depending on the computer's circuit design, the computer's output signal is divided into a composite signal or a TTL signal, each of which must be equipped with a monitor configured with a circuit suitable for their own unique signal time chart. . In addition, as the demand for computers is rapidly increasing, it is necessary to develop convenient monitors that can increase consumer preferences due to the increased demand for the monitors.

SUMMARY OF THE INVENTION The present invention solves the above problems, and an object thereof is to provide a computer monitor capable of freely selecting and operating output signals of different types of computers.

Another object of the present invention is to provide a computer monitor having a circuit configuration and characteristics suitable for output signals of different computers.

In order to achieve the above object, according to the present invention, a monitor circuit operated according to an output signal method of a computer, that is, a composite signal method and a TTL signal method, includes a horizontal shift circuit and a vertical oscillation circuit included in a horizontal oscillation drive circuit of the monitor circuit. A peripheral correction circuit is set up including a vertical shift circuit included in an output circuit and a flyback transformer suitable for a signal time chart. The plurality of switch terminals may be connected to one circuit select switch, and the circuit select switches may freely select and operate output signals of different computers.

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

FIG. 1 is a block diagram showing a computer monitor operating in a conventional composite signal method, in which 1 is a composite signal output through an RCA jack of a computer, a composite signal mixed with a video signal, a horizontal and a vertical signal, and 2 Since the level of the composite signal (1) is usually 1V, the composite signal amplifying circuit for amplifying the composite level to drive the video output stage without a bandwidth reduction, 3 is a composite signal (1) output from the composite signal amplifying circuit (2) ) Is a synchronous separation circuit for separating the video signal into horizontal and vertical synchronization signals, 4 is a pedestal clamp circuit for stabilizing the brightness of the video signal using the synchronous separation signal, and 5 is a composite signal amplification circuit ( The signal output from 2) is stably output by the bias voltage controlled by the pedestal clamp circuit (4) A video signal output circuit for supplying a cathode of a cathode ray tube (CRT), 6 further separates a horizontal synchronizing signal and a vertical synchronizing signal from the synchronizing signal outputted to the synchronizing separation circuit 3, and a vertical synchronizing signal. Is a horizontal oscillation and drive circuit which outputs to a vertical oscillation and output circuit and a horizontal synchronous signal is applied to a self oscillation circuit so that a horizontal output stage can drive a synchronized horizontal deflection signal, and 7 is a horizontal oscillation and a drive circuit 6 Vertical oscillation and output circuit driving 8 separate vertical synchronous signals and amplifying the current and outputting them to the vertical deflection yoke (V-DY) of the CRT and outputting them to the blanking circuit (9). A horizontal output circuit for outputting to the synchronized horizontal deflection yoke (H-DY) output from the oscillation and drive circuit 6, where 9 is used for scanning during the horizontal and vertical retrace periods. Is a retrace circuit for canceling retraces by applying a negative pulse to the first grid, and 10 is an FBT that provides the design and operating voltage required for the CRT by receiving the output signal of the horizontal output circuit 8. .

11 is a CRT, which consists of an electron gun that connects the electrons controlled by the Youngsan signal to form a thin beam, and a fluorescent film that emits light when the electrons collide. It is an electron tube. 12 is a power supply circuit for converting the AC voltage input from the external power supply terminal to a DC voltage suitable for the monitor circuit.

2 is a block diagram of a computer monitor of a conventional TTL signal system. 13, 14, and 15 are TTL video signals, TTL vertical sync signals, and TTL horizontal sync signals, respectively, which are output from the computer connector.

Since the level of the TTL video signal 13 outputted through the connector of the computer is usually 4V, the level of the TTL video signal 13 is not suitable for driving the video signal output circuit 5 because the signal level is high in this state. Is a TTL video signal driving circuit for driving the video signal output circuit 5 by adjusting a signal level voltage suitable for driving the video signal output circuit 5, 21 is a TTL vertical pulse signal 14 outputted through a connector of the computer. Is a TTL vertical signal drive circuit for driving the vertical oscillation and output circuits 7 as the synchronous differential waveforms required for the operation of the vertical oscillation and output circuits 7, and 22 is a horizontal (+) pulse which is a TTL horizontal synchronization signal 15. It is a TTL horizontal signal driving circuit for driving the horizontal output circuit 8 by converting a signal into a current amplification and a negative pulse signal necessary for driving the horizontal output circuit 8. The role of the following block diagram is the same as that of the composite signal method, but since the signal methods are different from each other, each of them has a unique circuit design.

3 is a block diagram showing a computer monitor of the present invention which can operate a composite signal method and a TTL signal method of a conventional computer. In the present invention, the composite amplification circuit 2 of FIG. 1 and the TTL video signal driving circuit 20 of FIG. 2 are selected and connected to the video signal output circuit 5. To the first oscillation terminal 16, and to select the horizontal oscillation and drive circuit 6 of FIG. 1 and the TTL vertical signal driver circuit 21 of FIG. The second switch 17 is connected between them, and the horizontal oscillation of FIG. 1 and the drive circuit 6 of FIG. 1 and the TTL horizontal signal driving circuit 22 of FIG. 2 are selected and connected to the horizontal output circuit. Since the output signal type of the FBT 10 is different from the composite signal type and the TTL signal type, the fourth switch terminal 19 is connected to the three switch terminals 18 so as to selectively connect them to the FBT designed in the present invention. With horizontal output circuit (8) The connection was made between the FBTs 10.

However, these first, second, third, and fourth switch terminals 16, 17, 18, and 19 are all connected to one circuit selector switch 5, and the circuit selector switch is switched to a TTL method or a composite method. As a result, the first, second, third and fourth switch terminals are simultaneously switched to a TTL or composite method. In addition, the circuit selection switch 25 includes a fifth switch terminal (Fig. 6) included in the vertical shift circuit.

Further, in the present invention, the resin shift circuit 24 and the horizontal shift 23 are interposed therebetween in order to fit the vertical oscillation and output circuits 7 and the horizontal oscillation and drive circuits 6 to the TTL signal system and the composite signal system. The FBT 10 was modified to be suitable for the present invention using the fourth switch terminal 19. The vertical shift circuit 24, the horizontal shift circuit 23 and the FBT 10 are defined as peripheral correction circuits in the present invention, which will be described later with reference to FIG.

4 is a detailed block diagram of FIG. 3, which is an embodiment of the present invention, and FIG. 5 is a signal waveform diagram of the present invention.

First, in FIG. 4, the AC voltage input from the external power supply terminal is converted into a DC voltage in the power supply circuit 12 and supplied to the monitor circuit. That is, when a power supply voltage enters the power supply circuit 12 from an external power supply terminal, it is input to the transformer 12b through the high frequency signal filter 12a. In this transformer 12b, the AC voltage is reduced to about 20V. .

The downed AC voltage is converted into a DC voltage via the diode rectifying circuit 12c, and then made into a DC 15V in the voltage stabilizing IC circuit 12d and supplied to each circuit of the monitor. When the circuit selection switch 25 is switched to the composite signal method, the first, second, third, and fourth switch terminals 16, 17, 18, and 19 are simultaneously selected as the composite signal method.

The composite signal 1 (see also fifth (a)) from the RCA jack of the computer is input to the composite signal amplifying circuit 2.

The two transistors TR ₁ and TR _{2 of} the composite signal amplifying circuit 2 perform two-stage amplification to increase the composite signal 1 of about 1V _PP (voltage of peak to peak value) to about 2.5V _PP . It works.

The resistors R ₁ and R ₂ are for applying the bias voltage of the transistor TR ₁ , and C ₁ is a coupling capacitor. Transistors TR ₁ and TR ₂ combine NPN and PNP transistors in a complementary state to improve frequency characteristics and stabilize them.

C ₂ is a coupling capacitor for connecting the amplified composite signal to the video signal output circuit 5. The output waveform of this coupling capacitor C ₂ is the same as that of the fifth (b).

The signal output from the composite signal amplifying circuit 2 is input to the video signal output circuit 5 and the synchronous separation circuit 3. The signal input to the image signal 5 is driven by the transistor TR ₅ and signal amplified by the transistor TR _{4. The} current voltage obtained from the FBT secondary side is converted into the peak coil L ₁ and the load resistance R ₂₂ . Is supplied to the cathode K of the CRT 11, and an image amplification signal is loaded on the current voltage to determine the degree of luminance.

On the other hand, via a signal from the transient substation emitter (TR ₃₎ is input to a sync separation circuit 3. The horizontal and vertical synchronous signals are separated from the synchronous separation circuit 3, and the vertical synchronous signals are separated from the oscillation and driving at the horizontal oscillation and drive circuit 6, and the vertical synchronous signals are represented as shown in the waveform of FIG. 5 (d). It is input to the vertical oscillation and output circuit 7 via ba of the second switch terminal 17. On the other hand, the horizontal synchronous signal is input to the horizontal output circuit 8 via the horizontal oscillation drive circuit 6 through the ba of the third switch terminal 18 as shown in the waveform shown in FIG.

The horizontal synchronizing signal input to the horizontal output circuit 8 is input to the primary side and the blanking circuit 9 of the FBT via the fourth switch terminal 19 and at the same time the horizontal deflection yoke H-DY of the CRT 11. Is entered. The vertical synchronization signal from the horizontal oscillation and the b terminal of the drive circuit 6 is inputted to the IC terminal d of the vertical oscillation and output circuit 7 via the second switch terminal 17 and simultaneously oscillated and driven amplified. The signals output from the output terminals e and f are respectively input to the blanking cancel circuit 9 and the vertical deflection circuit V-DY of the CRT 11. The waveform of the terminal e of the vertical oscillation and output circuit 7 is shown in FIG. 5 (f). Since the horizontal deflection signal and the vertical deflection signal inputted to the retrace clear circuit 9 are separated by the retrace clear circuit 9 and inverted by only the positive pulse at the time of retrace, they are applied to the first league G ₁ . During the trace period, the electron beam is cut so that no return occurs. On the other hand, the horizontal synchronous signal input through the fourth terminal 19 is resonated by the capacitance of the selected capacitor and the electrical characteristics of the FBT 10 to generate a high voltage, and induces the secondary voltage of the FBT to induce each of the CRTs 11. The information by the composite signal system is displayed by supplying the power required for the electrodes G ₁ , G ₂ , G ₄ , HV and the image signal output circuit 5 to enable the electron beam shape.

The following describes the TTL signal monitor circuit. As described above, when the circuit selection switch 25 is switched to the TTL signal method, the first, second, third, and fourth switch terminals 16, 17, 18, and 19 are simultaneously selected as the TTL signal method. The TTL image signal 13 from the connector of the computer is input to the image signal output circuit 5 through the first switch terminal 16 via the TTL image signal driving circuit 20, which is a transistor (as described above). TR ₅ ) to be amplified by transistor TR ₄ , and to supply the DC voltage obtained from the FBT secondary side to the cathode K through the peak coil L ₁ and the load resistor R ₂₂ . The image amplification signal is loaded on the voltage to determine the degree of luminance.

The vertical synchronous signal 14 from the connector of the computer is input to the IC terminal d of the vertical oscillation and output circuit 7 via the second switch terminal 17 via the TTL vertical signal driving circuit 21. The vertical synchronous signal input to the terminal (d) is oscillated, driven, and amplified by the vertical oscillation and output circuit (7), and the signal output from the terminals (e, f) is fed to the blanking circuit (9) and the vertical deflection yoke (V). -DY) respectively.

On the other hand, the horizontal synchronizing signal 15 from the connector of the computer is sent to the horizontal output circuit 8 via the third switch terminal via the TTL horizontal signal driving circuit. Here, a horizontal deflection signal is generated and input to the blanking cancellation circuit 9 and the horizontal deflection yoke H-DY of the CRT. In addition, the fourth switch terminal 19 induces a high voltage to the CRT by the first resonance of the capacitor and the FBT 10 and the capacitor already selected by the TTL signal method, and the electrodes G ₁ , G ₂ , G ₄ and HV of the CRT. And a secondary power source necessary for the video signal output circuit 5 to accelerate the connection of the electronic beam, the video signal from the video signal output circuit 5, the vertical deflection current of the vertical deflection yoke (V-DY), According to the horizontal deflection current of the horizontal deflection yoke H-DY, information by the TTL signal system is displayed on the CRT 11.

6 (a) to 6 (c) show the horizontal shift circuit, the vertical shift circuit, and the FBT circuit of FIG. 3, which are one embodiment of the present invention, in detail. These are the periphery of the computer monitor applied to the embodiment of the present invention. Configure the correction circuit.

First, the horizontal shift circuit in FIG. 6 (a) will be described. The pin P ₅ of the horizontal oscillation and drive circuit 6 compares the fly back pulse with the oscillator waveform to adjust the current. The adjustment is made by limiting and shifting the output phase by a filter consisting of a resistor R ₃₀₅ and a capacitor C ₃₀₅ . The horizontal frequency of the composite signal method and the TTL signal method is 15.75KHz and 18.449KHz, respectively, so the flyback time of the horizontal output is different and the video section is different, so the image horizontal center is not exactly matched. Therefore, in the TTL signal system, the horizontal image center is adjusted to a ring magnet of a horizontal deflection yoke (H-DY), and in the composite signal system, the horizontal horizontal shift circuit is used to match the image horizontal center. The following describes the vertical shift circuit in FIG. 6 (b).

The sawtooth wave current is formed and supplied to the vertical deflection yoke V-DY by the pins P ₄ and P ₁₀ of the vertical oscillation and output circuit 7. Since the vertical shift circuit 24 has a vertical frequency of 50 Hz or 60 Hz in the composite signal method and the TTL signal method, the vertical vertical center of the vertical shift circuit 24 does not exactly match. The problem is that there is no problem in centering the image vertically with the ring magnet of the vertical deflection yoke (V-DY) in one output signal method, but there is no problem in using the composite signal method and the TTL signal method. Accurate adjustment cannot be solved with ring magnets for vertical deflection yoke (V-DY). Therefore, composite signal type video signal is centered vertically with ring magnet, and TTL signal type moves the raster itself by applying potential of power supply voltage (B +) to sawtooth current applied to vertical deflection yoke (V-DY). Accurately align the vertical center of the image.

In addition, the vertical deflection signal has a different vertical signal width according to the vertical frequency difference between the TTL signal method and the composite signal method. The conventional vertical signal width adjustment in one type of output signal system adjusts the vertical oscillation and pin P ₇ output voltage levels of the output circuit 7 as the variable resistor P ₅₂₈ .

However, in the TTL and composite signal systems of the present invention, since the vertical frequencies are 50 Hz and 60 Hz, the difference in the frequencies varies depending on the voltage difference at the pin P ₇ . Substantially, about 50 m / m is large in the TTL signal system. Therefore, in TTL signaling, a resistor (R ₅₂₃ ) is added to make the vertical-to-horizontal width generally meet the ideal specification (vertical: horizontal = 3: 4).

Next, a circuit diagram of the FBT of FIG. 6 (c) will be described. In general, the FBT 10 is operated by a characteristic design value of a single output signal system. Here, general circuit characteristics of the FBT 10 of the present invention are described, and the circuit operation is omitted. The characteristic design value of the composite signal method and the characteristic design value of the TTL signal method solved the different output signal methods as one FBT as shown in the following Table 1. This prevents the characteristics of each output signal method from operating in the reverse direction and The solution was solved by selecting the capacitance value of the primary-side resonant capacitor of the FBT to satisfy the characteristics of the signaling system.

In more detail, the integer of FBT and H-DY, which are applied in the present invention, are fixed by experimental adjustments to suit two signal types, and as can be seen in Table 1 below, the present invention is simple. It is also measured by the monitor.

Thus, the present invention determines the time constant of the resonant capacitor by the constant of the FBT and the horizontal deflection yoke (H-DY), and determines the secondary voltage, retrace period and horizontal width according to the characteristics of each signal type. At the same time, the appropriate sawtooth waveform of the horizontal deflection yoke (H-DY) is formed.

Accordingly, the secondary winding of the FBT generates the voltage of the high voltage electrode HV through the diode D ₆₀₆ , determines the second grid voltage through the resistor R ₆₀₂ and the diode D ₆₀₃ , and determines the diode D. The voltage of the first grid is determined by the voltage of ₆₀₂ and the voltage of the diode D ₆₀₄ . Of course, the power supply of the FBT is passed through the switchgear (C ₆₀₄ ) to provide a boosted voltage to the primary winding.

TABLE 1

The characteristics of the reverse direction described above can be displayed within the conventional raster range when the horizontal frequency of the TTL output signal type is 18.449 KHz and the retrace time is 7.3 μS. The median of variable width should be 204m / m and the capacitance of resonant capacitor should be 0.039μF. Here, the characteristics of the TTL output signal type as FBT of one circuit are not matched with 180m / m because the high voltage rises to 19KV when the composite signal type is applied. Thus, by adjusting the primary and secondary windings of the FBT 10 of the present invention to match the screen width, the capacitance of the resonant capacitor satisfying the characteristic value is converted.

As described above, the conventional computer monitor has to select a correction circuit suitable for the circuit configuration and characteristics of the monitor itself according to the output signal method of the computer, but the present invention provides an output signal method of a computer having different types and functions. There is an effect that can provide a monitor circuit that can operate irrespective of, and increase the preference of consumers according to the increasing demand for computer monitors that are spreading around the world.

Claims (5)

In the computer monitor operated according to the output signal type of computer having different kinds and functions, a plurality of switches for combining the composite signal type computer monitor circuit and the TTL signal type computer monitor circuit without overlapping each other. A circuit selection switch 25 having integrated terminals 16, 17, 18, 19 and 26, and a horizontal shift circuit 23 connected to a horizontal oscillation and drive circuit 6, a vertical oscillation and an output circuit 7 And a peripheral correction circuit comprising a vertical shift circuit (24) and a flyback transformer (10) for selectively outputting a composite video signal and a TTL video signal. 2. The computer monitor according to claim 1, wherein a plurality of switch terminals of the circuit selection switch are simultaneously switched to a composite signal method or a TTL signal method. The computer as claimed in claim 1, wherein the horizontal shift circuit (23) comprises a filter comprising a resistor (R ₃₀₅ ) and a capacitor (C ₃₀₅ ) for limiting and shifting the output phase of the horizontal oscillation and drive circuits. monitor. The method of claim 1, wherein the vertical shift circuit 24 by installing a composite signal method and the terminal of the vertical oscillation and output circuitry for selective vertical signal width adjustment of the TTL signaling switch 26 to the (P _7), variable A monitor for a computer, characterized in that it selectively connects a resistor (R ₅₂₃ ) to a resistor (R ₅₀₈ ). 2. The flyback transformer (10) according to claim 1, wherein the flyback transformer (10) comprises a switch (19) and a capacitor (19) for the capacitance value of the primary side resonant capacitor of the transformer to satisfy each of the composite and TTL signal output signals. C ₆₀₁ , C ₆₀₂ ).

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