KR100706738B1 - Display unit for a flat panel display apparatus - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display unit of a flat panel display device, and implements to transmit color data in a reduced swing differential signaling (RSDS) method, and wires and components to a control board. This is an improvement to the rules implemented. In the display unit, the control board having a multi-layer structure has a wire for transmitting data to the column drive integrated circuit in a swing attenuated differential signal manner on one side, and a ground panel layer on the lower layer of the wire, Wires are formed on the lower layers to apply other signals including a gray voltage and a power source.

Therefore, while electromagnetic waves and noise are prevented on the display unit of the flat panel display device, signal interference between wires can be prevented and timing margin can be secured. In addition, noise may be prevented without adding a separate component, and the flat area of the control board may be reduced, thereby making the flat panel display device slim.

Description

Display unit for a flat panel display apparatus

1 is a block diagram showing a driving circuit of a flat panel display device according to the present invention.

2 is a plan view of a display unit of a flat panel display device according to the present invention;

3 is a circuit diagram illustrating a swing attenuated differential signal transmission method between a controller and a column drive integrated circuit.

4 is a waveform diagram illustrating an example of a swing attenuated differential signal transmitted by FIG. 3;

5 is a partial cross-sectional view illustrating an example of a control board configured in the display unit of FIG. 2.

6 is a partial cross-sectional view showing another example of a control board configured in the display unit of FIG.

FIG. 7 is a partial cross-sectional view illustrating still another example of a control board configured in the display unit of FIG. 2. FIG.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display unit of a flat panel display device, and more particularly, to transmit color data in a reduced swing differential signaling (RSDS) method and to wire the control board. The display unit of the flat panel display device with improved rules for mounting the components and components.

Recently, a flat panel display device is rapidly replacing a display device using a cathode ray tube, and various technologies have been developed and applied to realize a high quality and a large screen in a flat panel display device.

In the development of a flat panel display device, the electromagnetic interference problem and the timing margin problem are intrinsic problems to be solved. To solve this problem, enormous development costs and development time are required, and the above-mentioned problems require loss due to mass defects at the time of mass production. It is pointed out as the main cause.

In particular, the electromagnetic interference problem occurs most frequently in the wiring for transmitting data signals between the timing controller mounted on the printed circuit board and the column drive integrated circuit, and then occurs in the signal input portion between the user connector and the interface integrated circuit.

In order to solve this problem, various methods have been taken for flat panel display devices, and currently, efforts to solve the electromagnetic interference problem have been made in four ways as follows.                         

First, the most basic countermeasure may be to effectively design the ground panel of the circuit board, but the electromagnetic wave through the design change of the ground panel in the trend that the technology is developed in the direction of reducing the size of the printed circuit board to reduce the cost There is a limit to measures.

Second, in order to reinforce the limitation of the first method, a method of suppressing the signal itself by configuring a data filter in which a resistor, a capacitor, and an inductor are combined in a data transmission line is used.

Third, after applying the above method, additional materials for preventing electromagnetic interference such as metal tape or gasket are additionally mounted on the printed circuit board.

Fourth, the method of dividing the data to lower the frequency is applied.

However, the actual flat panel display apparatus has a problem due to the above-described methods themselves.

In the first method, when high-density wiring is formed on the inner layer of a printed circuit board, timing errors are likely to occur due to interference caused by magnetic fields generated by current flow between signals.

In the second method, the effect of electromagnetic interference can be improved by adding a filter to the data line, but the timing margin is greatly reduced due to the shift phenomenon due to the characteristics of the filter. In addition, since two or three filters are applied to each line, the number of parts is greatly increased.

In addition, the third method has a problem that the productivity is greatly reduced and the cost increases.

Finally, in the fourth method, data division requires the formation of a number of data lines proportional to the division ratio, and accordingly, an increase in the number of data filters, the timing controller and the number of input pins of the column drive integrated circuit is required. Problems such as raising the cost while increasing the area of the circuit board is caused.

Therefore, it is desired to propose a method of reducing the area of a printed circuit board while reducing the number of wirings while solving the above problems.

An object of the present invention is to prevent the mutual signal interference by improving the design rules of the wiring while reducing the influence of electromagnetic interference by the data transmission of the display unit of the flat panel display device to the RSDS method.

Another object of the present invention is to secure timing margins and solve electromagnetic interference without adding parts or distributing data by improving the design rule of the wiring.

Another object of the present invention is to reduce the manufacturing cost while slimming a printed circuit board on which wiring for transmitting signals for driving a flat panel display device is formed.

A display unit of a flat panel display device according to the present invention includes a liquid crystal panel for displaying a predetermined screen, a tape carrier package having one end connected to one end of the liquid crystal panel by mounting a column drive integrated circuit and the other end of the tape carrier package. And a control board that is physically and electrically connected to the liquid crystal panel, wherein the control board is formed of a multi-layered insulating material between layers, and a swing attenuated differential signal type data transmission is performed on the column drive integrated circuit at the uppermost layer. Wiring is formed, a ground panel is formed at a lower layer of the wiring for data transmission, a wiring for applying a gray voltage or power is formed at the lower layer of the ground panel, and a lower layer is electrically connected to the tape carrier package. Pad to be connected to It is sex.

A display unit of another flat panel display device according to the present invention includes a liquid crystal panel for displaying a predetermined screen, a tape carrier package having one end connected to one end of the liquid crystal panel by mounting a column drive integrated circuit, and the other end of the tape carrier package. And a control board connected to the liquid crystal panel and physically and electrically connected to the liquid crystal panel, wherein the control board is formed of a multilayer and has an insulating material between layers, and a wiring for red data transmission of a swing attenuated differential signal type on a top layer. A pad for connecting to the tape carrier package is formed, a wire for green data transmission of a swing attenuated differential signaling method is formed on a lower layer of the wire for red data transmission, and a wire for the green data transmission. Swing attenuated differential signaling on bottom layer The wiring for the blue color data is formed.

Hereinafter, exemplary embodiments of a display unit of a flat panel display device according to the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, the data is configured to be transmitted in the RSDS method, and the data transmission in the RSDS method reduces the amplitude of the signal to a level of 0.2V and transmits it as a pair of differential signals. Differential signal transmission transmits two signals in opposite phases in pairs, and this method is good for immunity such as noise commonly applied to both signals.

In addition, the RSDS scheme is a bi-division driving method that triggers on both the rising edge and the falling edge of the clock, and thus, phase synchronization is not applied and one-to-many data transmission is performed. Since this one-to-many data transmission is possible, the number of wires configured in the RSDS scheme is smaller than that of the TTL scheme. Specifically, tens of bit TTL signals may be transmitted as RSDS signals of several channels.                     

In the present specification, an embodiment will be described with reference to the configuration of a liquid crystal display device employing the above-described RSDS method as an example of a flat panel display device.

Referring to FIG. 1, a liquid crystal display device displays an image by driving the liquid crystal panel 10 by using driving data, driving control signals, and driving power provided from a predetermined image supply source.

The drive data, the drive control signal, and the drive power supply are provided from a predetermined image source such as a computer main body, the drive data includes R, G, and B data for representing a given screen, and the drive control signal is a vertical synchronization signal and a vertical synchronization signal. A signal, a data enable signal, and the like, and a DC voltage of a predetermined level is applied as a driving power source.

Among these, the drive data and the drive control signal are input to the controller 12 which generates column data and various control signals and then adjusts and outputs the timing, the drive power is input to the power supply unit 14, and the power supply unit 14 is level. Are applied to the controller 12, the gray voltage generator 16 and the gate voltage generator 18.

The controller 12 controls and outputs a timing format of the column data, generates a column control signal and a scan control signal for the column data, and outputs the column data and the column control signal to the column drive integrated circuits 20. The control signal is output to the scan drive integrated circuits 20.

Meanwhile, the gray voltage generator 18 generates a plurality of DC voltages having different values corresponding to the number of grays to be expressed as a voltage of a predetermined level applied from the power supply unit 14, thereby generating respective column drive integrated circuits. And to supply 20.

The gate voltage generator 18 generates a gate on / off voltage of a level for turning on / off a gate of the thin film transistor constituting each pixel of the liquid crystal panel 10 as a voltage applied from the power source 14. And to supply to the scan drive integrated circuit 22.

The liquid crystal panel 10 includes a plurality of column drive integrated circuits 20 for providing a column signal and a plurality of scan drive integrated circuits 22 for providing a scan signal, the number of which is the liquid crystal panel 10. ) Is determined by the resolution and size of the screen to be implemented.

The embodiment having the configuration as shown in FIG. 1 is configured as shown in FIG. 2, and the display unit is configured by the combination of the liquid crystal panel 10, the control board 30, and the tape carrier packages 32 and 34.

Referring to FIG. 2, the tape carrier packages 32 and 34 are physically and electrically connected in the longitudinal direction and the transverse direction of the liquid crystal panel 10, and the physical and electrical connection is made by an adhesive member such as an anisotropic conductive film. The scan drive integrated circuit 22 is mounted on the tape carrier package 32 in the longitudinal direction, and the column drive integrated circuit 20 is mounted on the tape carrier package 34 in the lateral direction.

Then, on the control board 30 which is a printed circuit board, a connector 36 for electrical connection with a predetermined image source is mounted at an arbitrary position, and the controller 12, the power supply unit 14, and the gray voltage generator are disposed on one surface. 16, components 38 constituting the gate voltage generator 18 are mounted, and wirings (not shown) for electrical connection therebetween are formed.

The control board 30 has a multilayer board structure in order to reduce the area while the above-described wirings are formed, and the wirings are formed on the same layer or another layer as the surface on which the components are mounted, as described later with reference to FIGS. 5, 6, and 7. Can be.

Pads (not shown) selectively connected to the wires are formed on one surface of the control board 32, and one ends of the tape carrier packages 34 in which the column drive integrated circuit 20 is mounted are overlapped. While being physically and electrically connected to the anisotropic conductive film. The other end of the tape carrier package 34 is physically and electrically connected to the anisotropic conductive film while overlapping the transverse edge of the liquid crystal panel 10.

Meanwhile, the scan drive integrated circuit 22 is mounted on the tape carrier package 32, and the tape carrier package 32 is physically and electrically connected to the anisotropic conductive film while overlapping the longitudinal edge of the liquid crystal panel 10. .

As described above, the components 38 are mounted on the control board 32, and the wirings for data transmission, the ground panel, and the wirings for supplying the gray voltage and power are formed on the surface or inside of the printed circuit board having a multilayer structure. Is formed.

In the above-described control board 32, the R, G, B data and the control signal is transmitted in the RSDS method, for this purpose, a wire for differential signal transmission is formed.

Specifically, an example of the wiring between the controller 12 and the column drive integrated circuit 20 for transmitting an RSDS signal is shown in FIG. 3, and an example of a waveform of the RSDS signal is shown in FIG. 4.

Referring to FIG. 3, in order to transmit an RSDS signal between the controller 12 and the column drive integrated circuit 20, a pair of wires connected to both ends of the termination resistor Rt is configured, and the pair of wires is configured on the controller 12. The inverted output terminal and the non-inverted output terminal of the buffer 40 are respectively connected.

The column drive integrated circuit 20 includes a buffer 44 and an input buffer 46 for receiving an output thereof. The buffer 44 has an inverting input terminal and a non-inverting input terminal to selectively select the inverted signal and the non-inverted signal. Is configured to output.

By the above-described configuration, the non-inverting signal D1 and the inverting signal D0 in Fig. 4 are output through the pair of wirings. D1 and D0 are the same signal and are out of phase. Therefore, it is resistant to noise due to differential signal characteristics.

As described above, the control board 32 may be configured as a design rule as shown in FIGS. 5, 6, and 7 as an embodiment of a circuit board for transmitting signals in the RSDS scheme.

Referring to FIG. 5, the circuit board has a multi-layer structure having four wiring layers, and wirings 50 for transmitting R, G, and B data of RSDS type are formed in the uppermost layer, and a part for driving in some regions 38) is mounted. In the lower layer, a ground panel 52 is formed, and in the lower layer, a wiring 54 for applying a gradation voltage or power is formed, and in the lower layer, a pad for electrically connecting with a tape carrier package in which a column drive is mounted. 56 is formed. Each layer is divided into a state in which layers 58, 60, and 62 of insulating resin are interposed therebetween.                     

Alternatively, the component 38 may be mounted on the lowermost layer. In this case, as shown in FIG. 6, wires 64 for R, G, and B data transmission in the RSDS scheme are formed. In the lower layer, a ground panel 66 is formed, and in the lower layer, a wiring 68 for applying a gradation voltage or power is formed, and in the lower layer, a pad for electrically connecting to a tape carrier package in which a column drive is mounted. 70 is formed and a part 34 for driving is mounted in a partial region. Each layer is divided into a state in which layers 72, 74, and 76 of insulating resin material are interposed therebetween.

5 and 6 described above, wiring for RSDS signal transmission is disposed on a different layer from other wirings, and in particular, separated by a ground panel, thereby preventing interference of RSDS signals by other signals. Therefore, electromagnetic interference can be prevented.

5 and 6, when the width W of each wiring is formed to be 0.11 mm, the separation distance D between the wiring pairs is preferably 0.13 mm, and the separation distance P between the wiring pairs is 0.26. It is preferably formed in mm.

The above values are for minimizing the value of the floating capacitance. When the wiring is actually larger than 0.12 mm, the data transmission speed is greatly reduced, and the separation distance D between the wirings of each pair is determined by the following equation (1). It is determined in consideration of the influence of the induced magnetic field, and the coupling between the wirings of each pair is also preferably determined at a level of about 1/4 of the influence of the coupling between the wirings included in the pair.

Here, dB is the density change of the magnetic field, μ is the permeablity, I is the amount of current, r is the radius vector, dl is the variable length variable (Length vector).

In view of the above Equation 1, the distance T1 between the wirings and the component or the distance T2 between the layers is preferably kept at least 0.26 mm, and at least 0.5 mm if possible.

In the above-described configuration, the embodiment according to the present invention transmits a signal in a RSDS scheme, and since the phase of the signal transmitted through the paired wiring is reversed and the amplitude is small, in each wiring due to the coupling effect between the paired wiring. The generated electromagnetic waves have an effect of canceling each other, and as a result, the emitted electromagnetic waves can be minimized.

In addition, as shown in FIGS. 5 and 6, the wirings 50 and 64 for transmitting the RSDS signal are formed on the uppermost layer while being formed on the layer on which the ground panels 52 and 66 are formed. Therefore, the RSDS signal can be transmitted at high speed because the wirings 50 and 64 are coupled only in one direction, i.e., in the direction in which the ground panels 52 and 66 are formed. As a result, the timing margin can be secured. In addition, since the RSDS signal is not affected by a signal transmitted through any other wiring formed in the lower layer by the ground panels 52 and 66 formed in the lower layer, the RSDS signal is not affected by the electromagnetic waves emitted by the other wiring.

In addition, RSDS signals are triggered at the rising and falling edges of the clock to be synchronized so that one-to-many (multidrop) data transmission is performed, thereby reducing the area occupied by the wiring, thus reducing wiring as compared to control boards using other signal transmission methods. The overall area can be reduced.

When the wiring width 'W' for transmitting the RSDS signal formed on the control board is formed to be 0.11 mm (5% or less in error range), as described above, the separation distance 'D' between the wirings in the differential relationship is equal to 0.13 mm. The distance 'P' between the pairs of wires formed in the error range and forming a differential relationship is 0.26 mm, and is formed in the same error range.

In addition, the distance 'T1' between the wiring and the adjacent parts forming the differential relationship and the distance between the ground panel and the distance 'T2' should be 0.26 mm and formed within the same error range, and should be kept at least 0.5 mm if possible.

In addition, a wire (not shown) of an inlet connected to the column drive integrated circuit 20 in the controller 12 maintains an obtuse angle. In addition, the bent portion of the wiring (not shown) of the data bus connecting the column drive integrated circuits 20 may be maintained at an obtuse angle as much as possible. Such obtuse angle maintenance of the wiring has an effect of preventing the signal from being scattered or distorted in the lead portion or the curved portion.

Meanwhile, as shown in FIG. 7, the size of the control board can be reduced by distributing wiring for transmitting data by RSDS.

Specifically, an RSDS signal wire 80 for transmitting R data and a pad 88 for connection with the tape carrier package 86 are formed on the uppermost layer, and an RSDS signal wire 82 for transmitting G data to the lower layer. And a power supply line 90 and a gamma line 92 are formed, and an RSDS signal line 84 and a TTL signal transmission line 94 and an extra gamma line 96 for transmitting B data are formed on the lower layer. The clock line 98 may be formed at the lowermost layer, and components may be mounted at the lowermost layer.

Therefore, when RSDS signals are divided into colors such as R, G, and B and arranged on different layers of a control board having a multilayer structure, a slimmer control board can be designed.

Therefore, according to the present invention, while preventing electromagnetic waves and noise on the display unit of the flat panel display device, signal interference between wires can be prevented and timing margin can be secured.

In addition, noise may be prevented without adding a separate component, and the flat area of the control board may be reduced, thereby making the flat panel display device slim.

Claims (8)

A liquid crystal panel displaying a predetermined screen; A tape carrier package mounted with a column drive integrated circuit and having one end connected to one end of the liquid crystal panel; And A control board connected to the other end of the tape carrier package and physically and electrically connected to the liquid crystal panel; The control board is formed of a multilayer and an insulating material is interposed between layers, and a wiring for data transmission of a swing attenuated differential signal type is formed in the column drive integrated circuit at a top layer, and a ground is formed at a lower layer of the wiring for data transmission. A panel is formed, a wiring for applying a gradation voltage or power is formed in the lower layer of the ground panel, and a pad for electrically connecting the tape carrier package is formed in a lowermost layer. . The method of claim 1, The control board is a display unit of the flat panel display device, characterized in that the component for driving the liquid crystal panel is mounted on the surface on which the wire for transmitting the data is formed. delete delete The method of claim 2, The wires for transmitting the swing attenuated differential signal are paired, and the separation distance between the paired wires and the other paired wires is greater than the separation distance from the other wires of the same pair. Display unit of flat panel display device. The method of claim 2, The wires for transmitting the swing attenuated differential signal are paired, and the distance between the wires for transmitting the data and the components to be mounted and the distance between the layers are greater than the distance between the other wires of the same pair. A display unit of a flat panel display device, characterized in that. The method of claim 1, The display unit of the flat panel display device, characterized in that the wiring between the column drive integrated circuit and the inlet portion connected to the column drive integrated circuit from the controller of the components mounted on the control board is formed at an obtuse angle. A liquid crystal panel displaying a predetermined screen; A tape carrier package mounted with a column drive integrated circuit and having one end connected to one end of the liquid crystal panel; And A control board connected to the other end of the tape carrier package and physically and electrically connected to the liquid crystal panel; The control board is formed of a multi-layered insulating material between the layers, a wiring for red data transmission of a swing attenuated differential signaling method and a pad for connecting with the tape carrier package is formed on the uppermost layer, and the red data transmission is performed. The wire for the green data transmission of the swing attenuated differential signaling method is formed on the lower layer of the wiring for, and the wire for the blue data transmission of the swing attenuated differential signaling method is formed on the lower layer of the wiring for green data transmission. A display unit of a flat panel display device, characterized in that.

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