KR20080001805A - Display device - Google Patents

Abstract

A display device is provided to install a connection package for packaging first and second electrostatic preventing units and a terminal resistor into one between plural signal lines transceiving data in a differential signaling transmission method, thereby reducing a number of parts and reducing production cost. A display device comprises a first and a second signal lines(116a,116b), a connection package(113), electrostatic preventing units(114a,114b), and a terminal resistor(118). The first and second signal lines transmit data in a differential signaling transmission method. The connection package is installed on the first and the second signal lines to prevent static electricity on the first and second signal lines and maintain the data. The electrostatic preventing unit is installed on the first and second signal lines to prevent the static electricity. The terminal resistor is connected between the first and second signal lines to maintain the data.

Description

Display device

1 is a view showing a liquid crystal display device using a conventional LVDS driving method.

2 is a view showing a liquid crystal display device according to the present invention.

3 shows a schematic illustration of the connection package of FIG. 2;

4 shows an internal circuit diagram of the connection package of FIG.

<Brief description of the main parts of the drawing>

102: liquid crystal panel 104: gate driver

106: data driver 108: timing controller

110: system 112: differential signal transmitter

113: connection package 114a: first antistatic portion

114b: second antistatic portion 115a to 115d: first to fourth diodes

116a: first signal line 116b: second signal line

118: terminating resistor 120: liquid crystal display module (LCM)

122: differential signal receiver 124: printed circuit board

130: Zener diode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly, to a display device capable of reducing the number of parts, increasing an effective area and reducing costs.

As the information society develops, the demand for display devices is increasing in various forms. In response to this, various flat panel display devices such as LCD (Liquid Crystal Display Device), PDP (Plasma Display Panel) and ELD (Electro Luminescent Display) have been studied. It is used as a display device.

Among them, liquid crystal displays are the most widely used, replacing CRTs for mobile image display devices because of their excellent image quality, light weight, thinness, and low power consumption. In addition to the mobile use, such as a variety of TV monitors have been developed.

A liquid crystal display device displays an image using the optical anisotropy and polarization property of the liquid crystal. Since the liquid crystal is thin and long in structure, the liquid crystal has directivity in the arrangement of molecules, and the direction of the molecular arrangement can be controlled by artificially applying an electric field to the liquid crystal.

The liquid crystal display includes an upper substrate including a common electrode and a color filter array, a lower substrate including a plurality of switching elements, a thin film transistor and a plurality of pixel electrodes, and a liquid crystal layer formed between the upper substrate and the lower substrate. It includes.

When a voltage is applied to the pixel electrode and the common electrode, a potential difference is generated between the two electrodes, thereby generating an electric field, thereby changing the arrangement of liquid crystal molecules of the liquid crystal layer by adjusting the electric field. When the arrangement of the liquid crystal molecules is changed, the transmittance of light passing through the liquid crystal layer is changed, so that a desired image may be displayed.

When transmitting data in the LCD, a large amount of transmission lines are required, and a large amount of electromagnetic interference (hereinafter, referred to as 'EMI') may occur in the transmission lines.

To solve this problem, signal transmission methods for transmitting differential signals such as Low Voltage Differential Signaling (LVDS) and Reduced Swing Differential Signaling (RSDS) are adopted.

In general, the LVDS is mainly used to transmit data from another system to a liquid crystal display module of a liquid crystal display device, and the RSDS is used to transmit data from a timing controller in the liquid crystal display device to a driver for driving the liquid crystal panel. .

The differential signal transmission method transmits desired data by using a voltage difference between two lines through which the positive and negative signals having opposite polarities are transmitted, respectively, and the voltages between the two lines. Even if the difference is low, the data can be easily recognized.

In the differential signal transmission method, the electromagnetic radiation (EMI) radiation may be minimized by eliminating electromagnetic waves of the positive and negative signals, and the positive and negative polarities may be reduced. ) Even if noise occurs in a signal, data loss is recognized because the data is recognized as a difference between the two signals.

1 is a view showing a liquid crystal display device using a conventional LVDS driving method.

As shown in FIG. 1, a conventional liquid crystal display device includes a liquid crystal display module 20 for displaying a predetermined image and a system 10 for supplying a plurality of control signals and data to the liquid crystal display module 20. Doing.

The system 10 includes a differential signal transmitter 12 for transmitting a plurality of data and control signals to the liquid crystal display module 20, and the liquid crystal display module 20 is supplied from the system 10. And a differential signal receiver 22 for receiving a plurality of data and control signals.

The differential signal transmitter 12 and the differential signal receiver 22 may be connected to a plurality of signal lines 16a and 16b formed on the printed board 24.

A plurality of antistatic parts 14a and 14b are mounted on the printed circuit board 24 to protect data and control signals supplied from the differential signal transmitter 12 to the differential signal receiver 22 from external static electricity. It is. Also. A terminating resistor 18 is connected between the signal lines 16a and 16b connected between the differential signal transmitter 12 and the differential signal receiver 22.

First and second antistatic portions 14a and 14b are connected to the first and second signal lines 16a and 16b, respectively, and as described above, between the first and second signal lines 16a and 16b. Likewise, the terminating resistor 18 is connected.

First and second antistatic parts 14a and 14b are connected to each of the plurality of signal lines 16a and 16b connecting the differential signal transmitter 12 and the differential signal receiver 22, and two pairs of signals are connected. A terminating resistor 18 is connected between the lines 16a and 16b, respectively.

As a result, a plurality of signal lines 16a and 16b connecting the differential signal transmitter 12 and the differential signal receiver 22 on the printed circuit board 24 and the antistatic unit 14a provided in each of the signal lines are provided. , The effective area is reduced due to the termination resistor 18 provided between the pair of signal lines 16a and 16b, and the antistatic portions 14a and 14b and the termination resistor 18) increases the number of parts.

If the number of parts increases, the cost also increases, and if the area of the printed circuit board 24 is increased to secure an effective area of the printed circuit board 24, the cost of the parts is lost due to static electricity generated from the outside, thereby controlling data and control. Problems occur when sending and receiving signals.

SUMMARY OF THE INVENTION An object of the present invention is to provide a display device having an interface for reducing costs and stably transmitting / receiving data and control signals using a differential signal transmission method.

The display device according to the present invention for achieving the above object is to maintain the data to prevent the static electricity on the first and second signal lines, and the first and second signal lines for transmitting data in a differential signal transmission method; It characterized in that it comprises a connection package provided on the first and second signal lines.

Hereinafter, with reference to the accompanying drawings will be described an embodiment according to the present invention.

2 is a view showing a liquid crystal display device according to the present invention.

As shown in FIG. 2, the liquid crystal display according to the present invention is driven by a system 110 for supplying a plurality of control signals and data and a control signal supplied from the system 110, and from the system 110. And a liquid crystal display module (LCM) 120 for displaying an image corresponding to the supplied data.

The liquid crystal display shown in FIG. 2 is shown as an example of the display device in order to facilitate the description of the embodiment according to the present invention.

The liquid crystal display according to the present invention uses the LVDS transmission method when transmitting data. The LVDS is a type of differential signal transmission method, and the differential signal transmission method recognizes data by a voltage difference across two lines through which positive polarity data and negative polarity data, respectively, having opposite polarities are transmitted. As a result, even if the voltage difference across the two lines is low, data can be easily recognized.

The system 110 supplies a vertical / horizontal synchronization signal (Vsync / Hsync), a data enable (DE) signal and a predetermined clock signal to the liquid crystal display module (LCM) 120, and supplies data in units of frames. .

The liquid crystal display module LCM 120 may include a timing controller configured to generate a gate control signal and a data control signal by using the vertical / horizontal synchronization signal Vsync / Hsync, a data enable signal, and a predetermined clock signal. 108, a gate driver 104 driven by the gate control signal, a data driver 106 driven by the data control signal, and a liquid crystal panel 102 displaying a predetermined image.

In the liquid crystal panel 102, a plurality of gate lines GL0 to GLn and data lines DL1 to DLm defining a plurality of pixel regions are arranged, and a thin film transistor TFT as a switching element is formed at an intersection thereof.

In addition, the liquid crystal panel 102 includes a liquid crystal layer formed between the first and second glass substrates and the first and second glass substrates. The image displayed on the liquid crystal panel 102 is determined according to the arrangement of the liquid crystal molecules constituting the liquid crystal layer.

The liquid crystal molecules are driven according to the potential difference between the data voltage supplied from the data driver 106 and the common voltage Vcom supplied to a common electrode (not shown) formed on the first glass substrate, thereby arranging the liquid crystal molecules. This is determined.

The gate driver 104 sequentially scans the plurality of gate lines GL0 to GLn according to the gate control signal generated by the timing controller 108, that is, the gate high voltage VGH and the gate low voltage VGL. ).

When the gate high voltage VGH is supplied to the gate lines GL0 to GLn, the thin film transistor TFT connected to the gate lines GL0 to GLn is turned on, and the gate lines GL0 to GLn are turned on. When the gate low voltage VGL is supplied to GLn, the thin film transistor TFT is turned off.

The data driver 106 supplies a data voltage to the plurality of data lines DL1 to DLm according to a data control signal generated from the timing controller 108. In addition, the data driver 106 converts the data arranged from the timing controller 108 into a data voltage that is an analog value using a gamma voltage and supplies the data voltage to the plurality of data lines DL1 to DLm.

The timing controller 108 uses a vertical / horizontal synchronization signal (Vsync / Hsync), a data enable (DE) signal, and a predetermined clock signal to control the gate driver 104 from the system 110. A control signal and a data control signal for controlling the data driver 106 are generated.

In addition, the timing controller 108 sorts and supplies the data of the frame unit supplied from the system 110 to the data driver 106.

The system 110 includes a differential signal transmitter 112 for transmitting a plurality of data and control signals to the liquid crystal display module LMC 120, in particular, the timing controller 108. Has a differential signal receiver 122 for receiving a plurality of data and control signals supplied from the system 110.

The differential signal receiver 122 receives the data and the control signal of the differential signal transmission method from the differential signal transmitter 112 of the system 110 for transmitting the signal in the differential signal transmission method and converts the original signal.

The differential signal transmitter 112 and the differential signal receiver 122 may be connected to a plurality of signal lines formed on the printed board 124. The differential signal transmitter 112 and the differential signal receiver 122 may be connected to the printed circuit board 124 as well as a flexible flat cable (FFC). Can be connected.

The differential signal transmitter 112 and the differential signal receiver 122 are connected to a plurality of signal lines, and the plurality of signal lines are connected to the connection package 113 by pairing two signal lines.

As shown in FIG. 3, the connection package 113 includes first and second antistatic parts 114a and 114b and a termination resistor 118. The first antistatic unit 114a is connected to the first signal line 116a and the second antistatic unit 114b is connected to the second signal line 116b.

A termination resistor 118 is connected between the first and second signal lines 116a and 116b, and the first and second antistatic parts 114a and 114b and the termination resistor 118 are connected in one connection package ( 113 is connected to a pair of the plurality of signal lines and mounted on the printed board 124.

The connection package 113 protects data supplied by the plurality of signal lines from the differential signal transmitter 112 to the differential signal receiver 122 and is supplied to the first and second signal lines 116a and 116b. It is to maintain the voltage difference of the data.

The termination resistor 118 formed in the connection package 113 is electrically connected to the first and second signal lines 116a and 116b to form a closed circuit. The termination resistor 118 prevents excessive current from flowing to the timing controller 108.

4 is a diagram illustrating an internal circuit diagram of the connection package of FIG. 2.

As shown in FIGS. 2 and 4, the internal circuit of the connection package 113 includes a first antistatic portion 114a including first and second diodes 115a and 115b, and third and fourth diodes. And a second antistatic portion 114b and a termination resistor 118 made of 115c and 115d.

As shown in FIG. 4, an input voltage Vcc and a ground voltage GND are supplied to the connection package 113. In other words, a zener diode 130 is provided in the connection package 113, and the zener diode 130 is connected to the input voltage Vcc and the ground voltage GND.

The first diode 115a is connected in the same direction as the second diode 115b, and the third diode 115c is connected in the same direction as the fourth diode 115d. The first and second diodes 115a are connected to the third and fourth diodes 115c and 115d to form first and second antistatic portions 114a and 114b.

When the first to fourth diodes 115a to 115d are supplied with static electricity from the outside to the connection package 113, the static electricity does not affect the first and second signal lines 116a and 116b. Prevents static electricity

The termination resistor 118 maintains a voltage difference between positive data and negative data supplied to the first and second signal lines 116a and 116b.

The positive data and the negative data supplied through the first and second signal lines 116a and 116b are supplied to the differential signal receiver 122 of the timing controller 108. Positive (+) data and negative (-) data supplied to the differential signal receiver 122 are supplied to the data driver 106 and displayed as a predetermined image on the liquid crystal panel 102.

When static electricity introduced from the outside is supplied to the first signal line 116a, the static electricity is supplied to the diodes provided in the first and second static electricity prevention parts 114a and 114b, and the static electricity provided by the diodes is The zener diode 130 is supplied.

In addition, when static electricity introduced from the outside is supplied to the second signal line 116b, the static electricity is supplied to the diodes provided in the first and second antistatic parts 114a and 114b and is provided as the diode. Static electricity is supplied to the zener diode 130.

Static electricity introduced from the outside is supplied to the first and second signal lines 116a and 116b and is supplied to the control diode 130 through the first and second antistatic portions 114a and 114b.

Due to this, the static electricity introduced from the outside is supplied to the control diode 130 of the connection package 113 and the positive polarity supplied to the first and second signal lines 116a and 116b due to the static electricity introduced from the outside. Positive and negative data are not affected.

As mentioned above, the first and second antistatic portions 114a and 114b and the terminating resistor 118 form one connection package 113 and are mounted on the printed board 124. The connection package 113 may be formed between a pair of first and second signal lines 116a and 116b among the plurality of signal lines or may be formed by integrating an IC form capable of connecting all of the plurality of signal lines. Can be.

Since the connection package 113 is mounted on the printed circuit board 124 including the first and second antistatic parts 114a and 114b and the termination resistor 118, the connection package on the printed circuit board 124. The area occupied by 113 may be smaller than the area occupied by the first and second antistatic portions 114a and 114b and the termination resistor 118, respectively.

In the conventional display device, the number of components increases as the antistatic unit and the terminating resistor are connected between the signal lines connecting the differential signal transmitter 112 and the differential signal receiver 122, respectively, thereby increasing the cost.

However, the display device according to the present invention packages the antistatic parts 114a and 114b and the terminating resistor 118 together into one connection package 113 to form the differential signal transmitter 112 and the differential signal receiver 122. By connecting to the signal lines to be connected can reduce the number of components compared to the conventional display device. As the number of parts is reduced, cost may be reduced, and the printed board 124 may be simplified.

In addition, the area occupied by the connection package 113 on the printed board 124 may be reduced to secure an effective area of the printed board 124. In addition, as the connection package 113 connects the signal lines, the distance between the differential signal transmitter 112 and the differential signal receiver 122 is reduced, and noise caused by the length of the signal lines and an increase in the length. Can be removed.

As the distance between the differential signal transmitter 112 and the differential signal receiver 122 is shortened, static electricity generated from the outside may be prevented from being supplied to the signal lines.

As mentioned above, the timing controller 108 receives data from the system 110 through a differential signal transmission method. The system 110 also supplies data to the timing controller 108 using differential signal transmission.

Data supplied through the differential signal transmission method to the timing controller 108 is supplied to the data driver 106. The data driver 106 also receives data from the timing controller 108 through the differential signal transmission method.

That is, the data driver 106 also receives data from the timing controller 108 in a differential signal transmission method.

The connection package 113 may also be used between the timing controller 108 and the data driver 106 to supply data from the timing controller 108 to the data driver 106. The timing controller 108 includes a differential signal transmitter (not shown) and transmits data to the data driver 106 through the differential signal transmitter in a differential signal transmission method.

A plurality of signal lines connecting the timing controller 108 and the data driver 106 are connected through the connection package 113, and the data arranged in the timing controller 108 may pass through the connection package 113. Is supplied to the data driver 106.

As a result, since the system 110, the timing controller 108, and the data driver 106 all use a differential signal transmission method, the differential signal transmitter of the system 110 and the differential signal receiver of the timing controller 108 are used. The connection package 113 is formed between the connection package 113 and the differential signal transmitter of the timing controller 108 and the data driver 106.

In an embodiment of the present invention, a connection package is connected between signal lines for transmitting and receiving differential signals between the system and the timing controller, and also between signal lines for transmitting and receiving differential signals between the timing controller and the data driver. Connecting the package has been described as an example.

However, the present invention is not limited thereto, and the present invention can be applied to all display devices that transmit / receive data in a differential signal transmission method.

As described above, the display device according to the present invention includes a connection package in which the first and second antistatic parts and the termination resistor are packaged as one between a plurality of signal lines for transmitting and receiving data in a differential signal transmission method. As a result, the number of parts may be reduced and manufacturing costs may be reduced as the number of parts is reduced, compared to the conventional display device in which the first and second antistatic parts and the termination resistor are separately provided between the plurality of signal lines.

In addition, as the area occupied by the connection package is reduced compared to the conventional display device having the first and second antistatic parts and the termination resistor, respectively, the transmitter and the data for transmitting data using the differential signal transmission method. The distance between the receivers receiving the H is shortened, thereby eliminating noise generated in proportion to the length of the signal lines.

The printed circuit board may be simplified as the connection package is mounted on a printed board on which the plurality of signal lines are formed.

Although the present invention has been described with reference to the embodiments, those skilled in the art may variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. You will understand.

Claims (6)

First and second signal lines for transmitting data in a differential signal transmission method; And a connection package provided on the first and second signal lines to prevent static electricity on the first and second signal lines and to maintain the data. The method of claim 1, An antistatic part provided on the first and second signal lines to prevent the static electricity; And And a termination resistor connected between the first and second signal lines to hold the data. The method of claim 1, The differential signal transmission method is a low voltage differential signaling (LVDS) method. The method of claim 2, And the termination prevention resistor and the termination resistor are integrated in one package. The method of claim 2, And the antistatic portion is composed of at least one diode. The method of claim 1, An LVDS transmitter for transmitting the data to the first and second signal lines; And And an LVDS receiver configured to receive data via the first and second signal lines.

Images