KR20200082181A - Display Device Including Static Discharging Unit - Google Patents

Abstract

The present invention provides a display device including a printed circuit board. The display device includes: a display panel including a compensation common wiring arranged in a non-display area surrounding a display area; a connection part including a first connection wire connected to the compensation common wiring; and an electrostatic discharge unit connected to the first connection wiring and discharging the static electricity of the compensation common wiring.

Description

Display Device Including Static Discharging Unit

The present invention relates to a display device, and more particularly, to a display device that prevents defects due to static electricity by forming an electrostatic discharge portion connected to a common wiring.

In accordance with the information age, the display field has also developed rapidly, and in response, a liquid crystal display device (LCD) as a flat panel display device (FPD) having advantages of thinning, lightening, and low power consumption. ), plasma display panel device (PDP), organic light emitting diode display device (OLED), field emission display device (FED), etc. It is rapidly replacing the cathode ray tube (CRT).

Such a display device includes a display panel for displaying an image and a driver for supplying a plurality of signals to the display panel, wherein the display panel includes a display unit used for image display and a non-display unit surrounding the display unit, and the driving unit is timing It includes a data driving unit and a gate driving unit that respectively generate data signals and gate signals using the signals of the control unit and the timing control unit and supply them to the display panel.

In addition, the display panel includes a common wiring and a ground wiring for transmitting a common voltage and a ground voltage to the display panel, respectively. The common wiring and the ground wiring are disposed on the non-display portion of the display panel.

However, in the manufacturing process of the display device or during the transfer of the completed display device, static electricity may be introduced into the display device, and various defects such as disconnection, short circuit, or breakage of the wiring or circuit may occur.

In particular, as the bezel area of the display device decreases, the line width of the common wiring of the display panel decreases, and as a result, the electrostatic discharge function of the driving integrated circuit does not sufficiently discharge static electricity, so the common wiring is more susceptible to static electricity. There is a problem.

And, when the operational amplifier to keep the common voltage constant is connected to the common wiring, there is a problem that the output terminal and the input terminal of the operational amplifier are vulnerable to static electricity.

To prevent this, a conductive tape may be attached to the non-display area of the display panel, but there is a problem in that the manufacturing cost of the display device is increased by the conductive tape.

The present invention has been proposed to solve this problem, and by forming an electrostatic discharge part connected to the common wiring, the static electricity introduced is sufficiently discharged to improve durability of the common wiring against static electricity and prevent defects caused by static electricity. It aims to provide.

Further, another object of the present invention is to provide a display device in which a separate conductive tape is omitted and manufacturing cost is reduced by forming an electrostatic discharge part connected to a common wiring.

In order to solve the above problems, the present invention, a display panel including a compensation common wiring disposed in a non-display area surrounding the display area; A connection unit including a first connection wiring connected to the compensation common wiring; A display device including a printed circuit board connected to the first connection wiring and including an electrostatic discharge unit for discharging static electricity of the compensation common wiring.

The display panel further includes a feedback common wiring connected to the compensation common wiring and outputting a feedback common voltage, and the connecting part further includes a second connection wiring connected to the feedback common wiring, and the printing. The circuit board may further include a feedback unit that generates a compensation common voltage using the feedback common voltage and transmits the generated common voltage to the compensation common wiring.

In addition, the feedback unit, a first resistor connected to the second connection wiring; A second resistor connected to the first resistor and the first connection wiring; A non-inverting input terminal may be connected to the PCB ground terminal, an inverting input terminal may be connected to the first resistor, and an output terminal may include an amplifier connected to the second resistor and the first connection wiring.

Further, the electrostatic discharge unit may include a first discharge diode having an anode connected to the PCB ground terminal and a cathode connected to the output terminal of the amplifier.

The electrostatic discharge unit may further include a second discharge diode having an anode connected to the PCB ground terminal and a cathode connected to the first resistor.

Further, the electrostatic discharge unit may include a first discharge diode having an anode connected to a hole ground terminal electrically independent of the PCB ground terminal and a cathode connected to the output terminal of the amplifier.

In addition, the connection unit is disposed between the ground transmission line for transmitting the ground voltage to the display panel, the common transmission line for transmitting the common voltage compensation to the first connection line, and the ground transmission line and the common transmission line. Further comprising a constant voltage transmission wiring for transmitting a constant voltage to the display panel, the printed circuit board may further include a power supply unit for supplying the compensation common voltage, and a PCB ground terminal for supplying the ground voltage.

In addition, the electrostatic discharge unit, a discharge resistance connected between the constant voltage transmission wiring and the power supply unit; And a discharge capacitor connected between the constant voltage transmission wiring and the PCB ground terminal and an electrically independent hole ground terminal.

In addition, the connection unit further includes a gate transfer wiring for transmitting a gate high voltage to the display panel, the power supply unit supplies the gate high voltage, and the discharge resistance is between the gate transfer wiring and the constant voltage transfer wiring. Can be connected to.

In addition, a common electrode and a touch wiring connected to the common electrode are disposed on the display panel, and the display panel displays an image by supplying a common voltage compensation to the touch wiring during the display period, and during the touch period, A touch can be sensed by supplying a modulated common voltage to the touch wiring.

The present invention, by forming an electrostatic discharge portion connected to the common wiring, has an effect that the discharged static electricity is sufficiently discharged to improve the durability of the common wiring against static electricity and prevent defects caused by static electricity.

In addition, the present invention has an effect of reducing the manufacturing cost by omitting a separate conductive tape by forming an electrostatic discharge part connected to the common wiring.

1 is a view showing a display device according to a first embodiment of the present invention.
2 is a view showing a display device according to a second embodiment of the present invention.
3 is a view showing a display device according to a third embodiment of the present invention.
4 is a view showing a display device according to a fourth embodiment of the present invention.

Hereinafter, a display device including an electrostatic discharge unit according to the present invention will be described with reference to the accompanying drawings.

1 is a view showing a display device according to a first embodiment of the present invention.

As shown in FIG. 1, the display device 110 according to the first embodiment of the present invention includes a display panel 120, a connection unit 130, and a printed circuit board (PCB) 140. do.

The display panel 120 displays an image using a gate voltage (gate signal) and a data voltage (data signal), and surrounds the display area DA and the display area DA that are substantially used for image display. It includes a non-display area NDA.

Although not shown, the display area DA includes a gate line and a data line that define pixels crossing each other, a thin film transistor connected to the gate line and the data line, a pixel electrode connected to the thin film transistor, and a pixel electrode. Corresponding common electrodes may be disposed.

When the display device 110 is an organic light emitting diode display device, a switching thin film transistor, a driving thin film transistor, a storage capacitor, and a light emitting diode may be disposed in the pixels of the display area DA of the display panel 120, and the display device 110 ) Is a liquid crystal display device, a pixel thin film transistor, a storage capacitor, and a liquid crystal capacitor may be disposed in a pixel of the display area DA of the display panel 120.

A plurality of pixel common wirings 122 connected to the common electrode are disposed in the display area DA along a horizontal pixel column, and a plurality of pixel common wirings 122 are connected to the non-display area NDA and the display area DA Compensation common wiring 124 in the shape of a square ring surrounding) and feedback common wiring 126 outside the compensation common wiring 124 are disposed.

In the first embodiment, it is exemplified that the plurality of pixel common wirings 122 are arranged parallel to the horizontal pixel column, but in other embodiments, the plurality of pixel common wirings 122 may be arranged parallel to the vertical pixel column.

The compensation common wiring 124 is connected to the plurality of pixel common wirings 122 and supplies the compensation common voltage Vcomc to the plurality of pixel common wirings 122. For example, the line width of the compensation common wiring 124 is The plurality of pixel common wirings 122 may be larger than the line width of each, and the line width of the upper side of the compensation common wiring 124 may be larger than the line widths of the lower, left, and right sides of the compensation common wiring 124.

The feedback common wiring 126 is connected to the upper side of the compensation common wiring 124 and outputs a feedback common voltage Vcomf from the compensation common wiring 124.

Meanwhile, the display panel 120 may be an in-cell type touch display panel using a common electrode for image display and touch sensing.

In this case, the display panel 120 is driven by dividing one frame into a display section and a touch section. During the display section, a data voltage, a gate voltage, and a compensation common voltage are supplied to the data wiring, the gate wiring, and the touch wiring, respectively. It is possible to detect the touch by supplying a modulated common voltage to the touch wiring during the touch period.

Here, during the display period, the data voltage is applied to the pixel electrode through the pixel thin film transistor, and the gate wiring including a gate voltage of a constant voltage type corresponding to the gate low voltage and a gate high voltage of a sequential pulse type is gate-wired. By applying to the gate electrode of the pixel thin film transistor and applying the compensation common voltage in the form of a constant voltage to the common electrode through the touch wiring, an image can be displayed.

In addition, during the touch section, a plurality of pulse-type modulation common voltages, which are touch signals, are applied to the common electrode through the touch wiring, and a plurality of pulse-type modulation gate voltages corresponding to the modulation common voltage are supplied to the gate wiring, thereby touching By reducing the parasitic capacitance between the wiring and the gate wiring and minimizing the load of the touch wiring, touch can be sensed, and as a result, touch sensitivity can be improved.

The connection unit 130 is connected between the display panel 120 and the printed circuit board 140 to transfer a plurality of signals, for example, the image data, data control signal and gate control signal of the printed circuit board 140 It can be transferred to the display panel 120.

Then, the connection unit 130 transmits the feedback common voltage Vcomf of the display panel 120 to the printed circuit board 140, and compensates the common voltage Vcomc of the printed circuit board 140 to the display panel 120. To this end, the connection unit 130 includes a first connection wiring 132 connected to the compensation common wiring 124 of the display panel 120 and a second connection of feedback common wiring 126 of the display panel 120. The connection wiring 134 is disposed.

For example, the connection unit 130 may be a flexible printed circuit (FPC) or a chip on film (COF).

The printed circuit board 140 generates a plurality of signals necessary for image display using signals from an external system and supplies the generated plurality of signals to the display panel 120 through the connection unit 130.

For example, a timing control unit (not shown) is disposed on the printed circuit board 140, and the timing control unit enables image signals, data enable, horizontal synchronization signals, and vertical synchronization signals transmitted from an external system such as a graphic card or a TV system. , Generates image data, data control signal and gate control signal using multiple timing signals such as clock, and generates the generated image data, data control signal and gate control signal to the display panel 120 through the connection unit 130 Can deliver.

When the display panel 120 is a touch display panel, the timing control unit may generate a touch synchronization signal, and the printed circuit board 140 may include a microcontroller unit that generates a selection signal using the touch synchronization signal, and a compensation common voltage. , A power supply unit for generating a gate low voltage, and a touch power unit for generating a modulation common voltage and a modulation gate voltage from the compensation common voltage and the gate low voltage according to the selection signal may be disposed.

Then, the printed circuit board 140 generates a compensation common voltage Vcomc using the feedback common voltage Vcoomf of the feedback common wiring 126, and the generated compensation common voltage Vcomc is compensated common wiring 124. To this, a feedback unit 142 is disposed on the printed circuit board 140 for this purpose.

The feedback unit 142 includes an amplifier AMP and first and second resistors R1 and R2.

The first terminal of the first resistor R1 is connected to the second connection wiring 134 of the connection unit 130, and the second terminal of the first resistor R1 is the first terminal of the second resistor R2 and the amplifier It is connected to the inverting input terminal (-) of (AMP).

The first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1 and the inverting input terminal (-) of the amplifier AMP, and the second terminal of the second resistor R2 is the amplifier AMP ) Is connected to the first connection wiring 132 of the output terminal and the connection unit 130.

The inverting input terminal (-) of the amplifier (AMP) is connected to the second terminal of the first resistor and the first terminal of the second resistor, and the non-inverting input terminal (+) of the amplifier (AMP) is connected to the PCB ground terminal (GNDP). The output terminal of the amplifier AMP is connected to the second terminal of the second resistor R2 and the first connection wiring 132 of the connector 130.

Here, the feedback unit 142 receives the feedback common voltage Vcomf transmitted through the second connection wiring 134 of the connection unit 130 from the feedback common wiring 126 of the display panel 120, and compensates the common voltage. (Vcomc) is output, and the outputted compensation common voltage Vcomc is supplied to the compensation common wiring 124 of the display panel 120 through the first connection wiring 132 of the connection unit 130.

The compensation common voltage Vcomc may be determined as follows by the first and second resistors R1 and R2 and the feedback common voltage Vcomf.

Vcomc = -(R2/R1)*Vcomf

As such, the compensation common voltage Vcomc can be maintained at a constant value by the feedback unit 142.

In addition, the printed circuit board 140 discharges static electricity of the compensation common wiring 124 to prevent defects caused by static electricity. To this end, an electrostatic discharge unit 144 is disposed on the printed circuit board 140.

The electrostatic discharge unit 144 includes a discharge diode DD, the positive electrode of the discharge diode DD is connected to the PCB ground terminal GNDP, and the negative electrode of the discharge diode DD is the amplifier of the feedback unit 142 ( AMP) and is connected to the first connection wiring 132 of the connection unit 130.

Here, when static electricity is not introduced into the compensation common wiring 124, the compensation common wiring 124 maintains the compensation common voltage Vcomc, and through the first connection wiring 132 to the compensation common wiring 124 Since the negative electrode of the connected discharge diode DD has a higher voltage than the positive electrode of the discharge diode DD connected to the PCB ground terminal GNDP having the ground voltage, no current flows through the discharge diode DD, and the display device 110 operates normally.

On the other hand, when negative static electricity flows into the compensation common wiring 124, the compensation common wiring 124 has a negative voltage and discharges to the compensation common wiring 124 through the first connection wiring 132. Since the cathode of the diode DD has a lower voltage than the anode of the discharge diode DD connected to the PCB ground terminal GNDP having the ground voltage, current flows through the discharge diode DD, and the compensation common wiring 124 Negative static electricity is discharged to the PCB ground terminal (GNDP) through the discharge diode (DD), and the defect of the display device 110 due to static electricity is prevented.

For example, in the case of a display device without an electrostatic discharge unit 144, when the voltages of about +11 kV and -11 kV are applied 10 times each, the characteristics are deteriorated, and the voltages of about +12 kV or more and -12 kV or less are each 10 times When applied, the power supply portion of the printed circuit board is damaged, while the display device 110 including the electrostatic discharge portion 144 improves the electrostatic discharge characteristics, even when voltages of about +19kV and -19kV are applied 10 times each. No defect occurs.

As described above, in the display device 110 according to the first embodiment of the present invention, the electrostatic discharge unit 144 including the discharge diode DD connected to the PCB ground terminal GNDP without using a separate conductive tape By connecting to the output terminal of the amplifier AMP of the feedback unit 142, the static electricity flowing into the compensation common wiring 124 can be quickly discharged to prevent defects in the compensation common wiring 124 and reduce manufacturing cost.

Meanwhile, in another embodiment, the static electricity of the feedback common wiring may also be discharged using a discharge diode, which will be described with reference to the drawings.

2 is a view illustrating a display device according to a second embodiment of the present invention, and description of the same parts as in the first embodiment will be omitted.

As shown in FIG. 2, the display device 210 according to the second embodiment of the present invention includes a display panel 220, a connection unit 230, and a printed circuit board (PCB) 240. do.

The display panel 220 displays an image using a gate voltage (gate signal) and a data voltage (data signal), and surrounds the display area DA and the display area DA that are substantially used for image display. It includes a non-display area NDA.

A plurality of pixel common wirings 222 are connected to the common electrode along the horizontal pixel column in the display area DA, and a plurality of pixel common wirings 222 are connected to the non-display area NDA and the display area DA Compensation common wiring 224 in the shape of a square ring surrounding) and feedback common wiring 226 outside the compensation common wiring 224 are disposed.

The compensation common wiring 224 is connected to the plurality of pixel common wirings 222 to supply the compensation common voltage Vcomc to the plurality of pixel common wirings 222, for example, the line width of the compensation common wiring 224 is The plurality of pixel common wirings 222 may be larger than the line widths of each of the pixels, and the line width of the upper side of the compensation common wiring 224 may be larger than the line widths of the lower, left, and right sides of the compensation common wiring 224.

The feedback common wiring 226 is connected to the upper side of the compensation common wiring 224 and outputs a feedback common voltage Vcomf from the compensation common wiring 224.

Meanwhile, the display panel 220 may be an in-cell type touch display panel using a common electrode for image display and touch sensing.

The connection unit 230 is connected between the display panel 220 and the printed circuit board 240 to transfer a plurality of signals, for example, the image data, data control signal and gate control signal of the printed circuit board 240 It can be transferred to the display panel 220.

In addition, the connection unit 230 transmits the feedback common voltage Vcomf of the display panel 220 to the printed circuit board 240, and compensates the common voltage Vcomc of the printed circuit board 240 to the display panel 220. To this end, the connection unit 230 includes a first connection wiring 232 connected to the compensation common wiring 224 of the display panel 220 and a second connection of feedback common wiring 226 of the display panel 220. The connection wiring 234 is disposed.

For example, the connection unit 230 may be a flexible printed circuit (FPC) or a chip on film (COF).

The printed circuit board 240 generates a plurality of signals necessary for image display using signals from an external system, and supplies the generated plurality of signals to the display panel 220 through the connection unit 230.

The printed circuit board 240 generates a compensation common voltage Vcomc using the feedback common voltage Vcoomf of the feedback common wiring 226, and transmits the generated compensation common voltage Vcomc to the compensation common wiring 224. However, for this purpose, a feedback unit 242 is disposed on the printed circuit board 240.

The feedback unit 242 includes an amplifier AMP and first and second resistors R1 and R2.

The first terminal of the first resistor R1 is connected to the second connecting wiring 234 of the connection unit 230, and the second terminal of the first resistor R1 is the first terminal of the second resistor R2 and the amplifier It is connected to the inverting input terminal (-) of (AMP).

The first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1 and the inverting input terminal (-) of the amplifier AMP, and the second terminal of the second resistor R2 is the amplifier AMP ) Is connected to the first connection wiring 232 of the output terminal and the connection unit 230.

The inverting input terminal (-) of the amplifier (AMP) is connected to the second terminal of the first resistor and the first terminal of the second resistor, and the non-inverting input terminal (+) of the amplifier (AMP) is connected to the PCB ground terminal (GNDP). The output terminal of the amplifier AMP is connected to the second terminal of the second resistor R2 and the first connection wiring 232 of the connector 230.

Here, the feedback unit 242 receives the feedback common voltage Vcomf transmitted through the second connection wiring 234 of the connection unit 230 from the feedback common wiring 226 of the display panel 220 and compensates the common voltage. (Vcomc) is output, and the outputted compensation common voltage Vcomc is supplied to the compensation common wiring 224 of the display panel 220 through the first connection wiring 232 of the connection unit 230.

The compensation common voltage Vcomc may be determined as follows by the first and second resistors R1 and R2 and the feedback common voltage Vcomf.

Vcomc = -(R2/R1)*Vcomf

As such, the compensation common voltage Vcomc can be maintained at a constant value by the feedback unit 242.

In addition, the printed circuit board 240 discharges static electricity from the compensation common wiring 224 and the feedback common wiring 226 to prevent defects caused by static electricity. To this end, the printed circuit board 240 has an electrostatic discharge unit 244 Is placed.

The electrostatic discharge unit 244 includes first and second discharge diodes DD1 and DD2, and the anodes of the first and second discharge diodes DD1 and DD2 are connected to the PCB ground terminal GNDP, The negative electrode of the discharge diode DD1 is connected to the output terminal of the amplifier AMP of the feedback unit 242 and the first connection wiring 232 of the connection unit 230, and the negative electrode of the second discharge diode DD2 is the feedback unit ( It is connected to the first end of the first resistor (R1) of 242 and the second connection wiring 234 of the connection portion 230.

Here, when static electricity does not flow into the compensation common wiring 224, the compensation common wiring 224 maintains the compensation common voltage Vcomc, and through the first connection wiring 232 to the compensation common wiring 224 Since the negative electrode of the first discharge diode DD1 connected has a higher voltage than the positive electrode of the first discharge diode DD1 connected to the PCB ground terminal GNDP having a ground voltage, the first discharge diode DD1 has a current. Does not flow.

And, when static electricity does not flow into the feedback common wiring 226, the feedback common wiring 226 maintains the feedback common voltage Vcomf, and the feedback common wiring 226 through the second connection wiring 234 Since the negative electrode of the second discharge diode DD2 connected has a higher voltage than the positive electrode of the second discharge diode DD2 connected to the PCB ground terminal GNDP having the ground voltage, the second discharge diode DD2 has a current Does not flow.

Accordingly, the display device 210 operates normally.

On the other hand, when negative static electricity is introduced into the compensation common wiring 224, the compensation common wiring 224 has a negative voltage and is connected to the compensation common wiring 224 through the first connection wiring 232. Since the negative electrode of the first discharge diode DD1 has a lower voltage than the positive electrode of the first discharge diode DD1 connected to the PCB ground terminal GNDP having a ground voltage, current flows through the first discharge diode DD1, The negative static electricity of the compensation common wiring 224 is discharged to the PCB ground terminal GNDP through the first discharge diode DD1.

In addition, when negative static electricity is introduced into the feedback common wiring 226, the feedback common wiring 226 has a negative voltage and is connected to the feedback common wiring 226 through the second connection wiring 234. Since the cathode of the 2 discharge diode DD2 has a lower voltage than the anode of the second discharge diode DD2 connected to the PCB ground terminal GNDP having the ground voltage, current flows through the second discharge diode DD2, The negative static electricity of the feedback common wiring 226 is discharged to the PCB ground terminal GNDP through the second discharge diode DD2.

Accordingly, a defect in the display device 210 due to static electricity is prevented.

As described above, in the display device 210 according to the second embodiment of the present invention, the first and second discharge diodes DD1 and DD2 are connected to the PCB ground terminal GNDP without using a separate conductive tape. By connecting the electrostatic discharge unit 244 to the output terminal and the input terminal of the amplifier AMP of the feedback unit 242, discharge the static electricity flowing into the compensation common wiring 224 and the feedback common wiring 226 quickly to compensate the common wiring 224 and the feedback common wiring 226 can be prevented from defective and the manufacturing cost can be reduced.

On the other hand, in another embodiment, it is possible to protect the components of the printed circuit board from static electricity discharged by connecting the discharge diode to a separate ground terminal, which will be described with reference to the drawings.

3 is a view illustrating a display device according to a third embodiment of the present invention, and descriptions of the same parts as in the first and second embodiments are omitted.

As shown in FIG. 3, the display device 310 according to the third embodiment of the present invention includes a display panel 320, a connection unit 330, and a printed circuit board (PCB) 340. do.

The display panel 320 displays an image using a gate voltage (gate signal) and a data voltage (data signal), and surrounds the display area DA and the display area DA that are substantially used for image display. It includes a non-display area NDA.

A plurality of pixel common wirings 322 are connected to the common electrode along the horizontal pixel column in the display area DA, and a plurality of pixel common wirings 322 are connected to the non-display area NDA and the display area DA Compensation common wiring 324 having a rectangular ring shape surrounding) and feedback common wiring 326 outside the compensation common wiring 324 are disposed.

The compensation common wiring 324 is connected to the plurality of pixel common wirings 322 to supply the compensation common voltage Vcomc to the plurality of pixel common wirings 322, for example, the line width of the compensation common wiring 324 is The plurality of pixel common wirings 322 may be larger than the line widths of the respective pixels, and the line width of the upper side of the compensation common wiring 324 may be larger than the line widths of the lower, left, and right sides of the compensation common wiring 324.

The feedback common wiring 326 is connected to the upper side of the compensation common wiring 324 and outputs a feedback common voltage Vcomf from the compensation common wiring 324.

Meanwhile, the display panel 320 may be an in-cell type touch display panel using a common electrode for image display and touch sensing.

The connection unit 330 is connected between the display panel 320 and the printed circuit board 340 to transfer a plurality of signals, for example, image data, data control signals, and gate control signals of the printed circuit board 340. It can be transferred to the display panel 320.

In addition, the connection unit 330 transmits the feedback common voltage Vcomf of the display panel 320 to the printed circuit board 340, and compensates the common voltage Vcomc of the printed circuit board 340 to the display panel 320. In order to do this, the connection unit 330 has a first connection wiring 332 connected to the compensation common wiring 324 of the display panel 320 and a second connection wiring of the feedback common wiring 326 of the display panel 320. The connection wiring 334 is disposed.

For example, the connection unit 330 may be a flexible printed circuit (FPC) or a chip on film (COF).

The printed circuit board 340 generates a plurality of signals necessary for image display using signals from an external system, and supplies the generated signals to the display panel 320 through the connection unit 330.

The printed circuit board 340 generates a compensation common voltage Vcomc using the feedback common voltage Vcoomf of the feedback common wiring 326, and transfers the generated compensation common voltage Vcomc to the compensation common wiring 324. However, for this purpose, a feedback unit 342 is disposed on the printed circuit board 340.

The feedback unit 342 includes an amplifier AMP, and first and second resistors R1 and R2.

The first terminal of the first resistor R1 is connected to the second connection wiring 334 of the connection unit 330, and the second terminal of the first resistor R1 is the first terminal of the second resistor R2 and the amplifier It is connected to the inverting input terminal (-) of (AMP).

The first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1 and the inverting input terminal (-) of the amplifier AMP, and the second terminal of the second resistor R2 is the amplifier AMP ) Is connected to the first connection wiring 332 of the output terminal and the connection unit 330.

The inverting input terminal (-) of the amplifier (AMP) is connected to the second terminal of the first resistor and the first terminal of the second resistor, and the non-inverting input terminal (+) of the amplifier (AMP) is connected to the PCB ground terminal (GNDP). The output terminal of the amplifier AMP is connected to the second terminal of the second resistor R2 and the first connection wiring 332 of the connector 230.

Here, the feedback unit 342 receives the feedback common voltage Vcomf transmitted through the second connection wiring 334 of the connection unit 330 from the feedback common wiring 326 of the display panel 320 and compensates the common voltage. (Vcomc) is output, and the outputted compensation common voltage Vcomc is supplied to the compensation common wiring 324 of the display panel 320 through the first connection wiring 332 of the connection unit 330.

The compensation common voltage Vcomc may be determined as follows by the first and second resistors R1 and R2 and the feedback common voltage Vcomf.

Vcomc = -(R2/R1)*Vcomf

As such, the compensation common voltage Vcomc can be maintained at a constant value by the feedback unit 342.

In addition, the printed circuit board 340 discharges static electricity of the compensation common wiring 324 to prevent defects caused by static electricity. To this end, an electrostatic discharge unit 344 is disposed on the printed circuit board 340.

The electrostatic discharge unit 344 includes a discharge diode DD, and an anode of the discharge diode DD is connected to a hole ground terminal GNDH that is electrically independent (isolated) from the PCB ground terminal GNDP, and the discharge diode The negative electrode of DD is connected to the output terminal of the amplifier AMP of the feedback unit 342 and the first connection wiring 332 of the connection unit 330.

Here, when static electricity is not introduced into the compensation common wiring 324, the compensation common wiring 324 maintains the compensation common voltage Vcomc, and through the first connection wiring 332 to the compensation common wiring 324 Since the negative electrode of the connected discharge diode DD has a higher voltage than the positive electrode of the discharge diode DD connected to the ground ground terminal GNDH having the ground voltage, no current flows through the discharge diode DD, and the display device does not flow. 310 operates normally.

On the other hand, when negative static electricity is introduced into the compensation common wiring 324, the compensation common wiring 324 has a negative voltage and discharges to the compensation common wiring 324 through the first connection wiring 332. Since the cathode of the diode DD has a lower voltage than the anode of the discharge diode DD connected to the ground ground terminal GNDH having a ground voltage, current flows through the discharge diode DD, and the compensation common wiring 324 is used. Negative static electricity is discharged to the ground contact terminal (GNDH) through the discharge diode (DD), and the failure of the display device 310 due to static electricity is prevented.

At this time, a number of devices, such as a timing control unit (not shown) and a power supply unit (446 in FIG. 4), are connected to the PCB ground terminal GNDP of the printed circuit board 340, and the introduced static electricity discharges the discharge diode DD. Through this, since the discharge is discharged to the hole ground terminal (GNDH) that is electrically independent from the PCB ground terminal (GNDP), a plurality of devices mounted on the printed circuit board 340 can be protected from static electricity.

As described above, in the display device 310 according to the third embodiment of the present invention, the electrostatic discharge unit 344 including the discharge diode DD connected to the hole ground terminal GNDH without using a separate conductive tape By connecting to the output terminal of the amplifier (AMP) of the feedback unit 342, the static electricity flowing into the compensation common wiring 324 can be quickly discharged to prevent defects in the compensation common wiring 324 and reduce manufacturing cost. At the same time, a plurality of parts mounted on the printed circuit board 340 can be protected from static electricity.

On the other hand, in another embodiment, by arranging a constant voltage transfer wiring between the common transfer wiring and the ground transfer wiring, it is possible to prevent static electricity from the ground transfer wiring from being transferred to the common transfer wiring, which will be described with reference to the drawings.

4 is a view illustrating a display device according to a fourth embodiment of the present invention, and description of the same parts as in the first to third embodiments will be omitted.

As shown in FIG. 4, the display device 410 according to the fourth embodiment of the present invention includes a display panel 420, a connection portion 430, and a printed circuit board (PCB) 440. do.

The display panel 420 displays an image using a gate voltage (gate signal) and a data voltage (data signal), and surrounds the display area DA and the display area DA that are substantially used for image display. It includes a non-display area NDA.

A plurality of pixel common wirings 4322 connected to a common electrode is disposed in the display area DA, and a plurality of pixel common wirings 422 are connected to the non-display area NDA and a display area DA ) Is provided with a square ring-shaped compensation common wiring 324 and a feedback common wiring 426 outside the compensation common wiring 424.

The compensation common wiring 424 is connected to the plurality of pixel common wirings 422 and supplies the compensation common voltage Vcomc to the plurality of pixel common wirings 422, for example, the line width of the compensation common wiring 424 is The plurality of pixel common wirings 422 may be larger than the line widths of the respective pixels, and the line widths of the upper side of the compensation common wirings 424 may be larger than the line widths of the lower, left, and right sides of the compensation common wirings 424.

The feedback common wiring 426 is connected to the upper side of the compensation common wiring 424 and outputs a feedback common voltage Vcomf from the compensation common wiring 424.

Meanwhile, the display panel 420 may be an in-cell type touch display panel using a common electrode for image display and touch sensing.

The connection unit 430 is connected between the display panel 420 and the printed circuit board 440 to transmit a plurality of signals, for example, image data, data control signals and gate control signals of the printed circuit board 440. It can be transferred to the display panel 420.

In addition, the connection unit 430 transmits the feedback common voltage Vcomf of the display panel 420 to the printed circuit board 440, and compensates the common voltage Vcomc of the printed circuit board 440 to the display panel 420. To this end, the connection unit 430 includes a first connection wiring 432 connected to the compensation common wiring 424 of the display panel 420 and a second connection wiring of the feedback common wiring 426 of the display panel 420. The connection wiring 434 is disposed.

In addition, the connection unit 430 transmits the compensation common voltage (Vcomc), the gate high voltage (Vgh), the constant voltage, and the ground voltage of the printed circuit board 440 to the display panel 420. To this end, the connection unit 430 has a connection unit The gate transmission line 452 connected to the gate driving part (not shown) of the display panel 420 or the gate high voltage Vgh is connected to the first connection line 432 of the connection part 430. A pile of the common transmission wiring 454 that transmits the compensation common voltage Vcomc, the ground transmission wiring 456 that is connected to a ground terminal (not shown) of the display panel 420 and transmits the ground voltage. However, a constant voltage transmission wiring 458 connected to a terminal (not shown) for transmitting a constant voltage is disposed.

For example, the connection unit 330 may be a flexible printed circuit (FPC) or a chip on film (COF).

Here, the constant voltage transmission wiring 458 is transferred to the constant voltage transmission wiring 458 instead of being transferred to the common transmission wiring 454 and the static electricity flowing into the ground transmission wiring 456 is the common transmission wiring 454 and the ground transmission wiring 456.

The printed circuit board 440 generates a plurality of signals necessary for image display using signals from an external system and supplies the generated plurality of signals to the display panel 420 through the connection unit 430.

Then, the printed circuit board 440 generates a plurality of power voltages and transmits them to the display panel 420. To this end, a power supply 446 is disposed on the printed circuit board 440.

The power supply unit 446 generates the compensation common voltage Vcomc and the gate high voltage Vgh, and the generated common common voltage Vcomc is connected to the common transmission wiring 454 and the first connection wiring 432 of the connection unit 430. Through the transfer to the compensation common wiring 424 of the display panel 420, and the generated gate high voltage (Vgh) through the gate transfer wiring 452 of the connection portion 430, the connection portion 430 or the display panel 420 To the gate driver (not shown).

The power unit 446 may be a power management integrated circuit (PMIC).

When the display panel 420 is a touch display panel, the power supply unit 446 may generate a compensation common voltage and a gate low voltage, and the timing controller and a touch synchronization signal that generate a touch synchronization signal on the printed circuit board 440. A microcontroller unit for generating a selection signal by using and a touch power unit for generating a modulation common voltage and a modulation gate voltage from a compensation common voltage and a gate low voltage according to the selection signal may be disposed.

In addition, the printed circuit board 440 transmits the ground voltage of the PCB ground terminal (GNDP) to the ground terminal of the display panel 420 through the ground transfer wiring 456 of the connection unit 430.

Meanwhile, the printed circuit board 440 generates a constant voltage using the gate high voltage Vgh of the power supply unit 446, and displays the generated constant voltage through the constant voltage transfer wiring 458 of the connection unit 430. ), and at the same time, the static electricity introduced into the ground transfer wiring 456 of the connection portion 430 is transferred to the constant voltage transfer wiring 458 of the connection portion 430 instead of the common transfer wiring 454 of the connection portion 430 to be grounded. However, it should be discharged to (GNDH).

To this end, an electrostatic discharge unit 444 is disposed on the printed circuit board 440.

The electrostatic discharge unit 444 includes a discharge resistor DR and a discharge capacitor DC. The first terminal of the discharge resistor DR is connected to the gate high voltage Vgh output terminal of the power supply unit 445, and the discharge resistor The second end of (DR) is connected to the first electrode of the discharge capacitor (DC) and the constant voltage transmission wiring 458 of the connection part 430, and the first electrode of the discharge capacitor (DC) is the first electrode of the discharge resistance (DR). It is connected to the second stage and the constant voltage transmission wiring 458 of the connection unit 430, and the second electrode of the discharge capacitor DC is connected to the hole ground terminal GNDH.

The discharge resistance DR may have a large-capacity resistance value of about 1 MΩ or more, and the PCB ground terminal GNDP and the hole ground terminal GNDH may be electrically independent (isolated) from each other.

The common transmission wiring 454 and the ground transmission wiring 456 in the connection part 430 are disposed adjacent to each other. As the bezel area of the display device 410 decreases, the common transmission wiring 454 and the ground transmission wiring 456 The gap between the two is also reduced, and as a result, static electricity introduced into the ground transfer wiring 456 may be transferred to the common transfer wiring 454, thereby causing a defect in the compensation common wiring 424.

In the display device 410 according to the fourth embodiment of the present invention, the constant voltage transmission wiring 458 is disposed between the common transmission wiring 454 and the ground transmission wiring 456, thereby flowing into the ground transmission wiring 456. Instead of the static electricity being transferred to the common transmission wiring 454, the static electricity is transferred to the constant voltage transmission wiring 458, and as a result, defects in the compensation common wiring 424 can be prevented.

Here, when no static electricity is introduced into the ground transfer wiring 456, the gate high voltage Vgh is lowered by the large-capacity discharge resistor DR, so that a relatively small constant voltage is connected to the constant voltage transfer wiring 458 of the connection unit 430. ) To the dummy end of the display panel 420, and the display device 410 operates normally.

On the other hand, when static electricity is introduced into the ground transmission wiring 456, most of the static electricity is discharged to the PCB ground terminal (GNDP), and some static electricity is transferred to the adjacent constant voltage transmission wiring 458 instead of the common transmission wiring 454. , The static electricity transferred to the constant voltage transmission wiring 458 is blocked by the large-capacity discharge resistance DR and is not discharged to the power supply unit 446, and discharged to the ground contact terminal GNDH through the discharge capacitor DC. As a result, defects in the display device 410 due to static electricity are prevented.

At this time, a plurality of devices such as a timing control unit (not shown) and a power supply unit 446 are connected to the PCB grounding terminal GNDP of the printed circuit board 440, and the introduced static electricity is grounded through the discharge capacitor DC. Since it is discharged from the GNDP to a hole ground terminal GNDH that is electrically independent, a plurality of devices mounted on the printed circuit board 440 can be protected from static electricity.

Although not shown, similar to the first to third embodiments, the printed circuit board 440 generates a compensation common voltage Vcomc using the feedback common voltage Vcoomf of the feedback common wiring 426, and generates The compensation common voltage Vcomc may be transmitted to the compensation common wiring 424, and a feedback unit may be disposed on the printed circuit board 440 for this purpose.

The feedback unit may include an amplifier, first and second resistors, and a feedback common voltage transmitted from the feedback common wiring 426 of the display panel 420 through the second connection wiring 434 of the connection unit 430 ( Vcomf) is input and outputs the compensation common voltage Vcomc, and the output common compensation voltage Vcomc is compensated common wiring 424 of the display panel 420 through the first connection wiring 232 of the connection unit 230 Can be supplied to.

At this time, the compensation common voltage Vcomc may be determined as follows by the first and second resistors and the feedback common voltage Vcomf.

Vcomc = -(R2/R1)*Vcomf

In this way, the compensation common voltage Vcomc can be maintained at a constant value by the feedback unit.

As described above, in the display device 410 according to the fourth embodiment of the present invention, the constant voltage transmission wiring between the common transmission wiring 454 and the ground transmission wiring 456 of the connection portion 430 without the use of a separate conductive tape. Arrange 458 and connect the electrostatic discharge unit 444 including the discharge resistor DR and the discharge capacitor DC connected to the ground ground terminal GNDH to the constant voltage transmission wiring 458, thereby providing ground transmission wiring. By quickly discharging static electricity introduced into the 456, it is possible to prevent defects in the compensation common wiring 424 and reduce manufacturing costs, and at the same time, a number of components mounted on the printed circuit board 440 can be protected from static electricity. .

Although described above with reference to preferred embodiments of the present invention, those skilled in the art variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. You can understand that you can.

110: display device 120: display panel
122: common pixel wiring 124: common compensation wiring
126: common feedback wiring 130: connection
132, 134: first and second connection wiring 140: printed circuit board
142: electrostatic discharge unit

Claims (10)

A display panel including a compensation common wiring disposed in a non-display area surrounding the display area;
A connection unit including a first connection wiring connected to the compensation common wiring;
A printed circuit board connected to the first connection wiring and including an electrostatic discharge unit for discharging static electricity of the compensation common wiring
Display device comprising a.
According to claim 1,
The display panel further includes a feedback common wiring connected to the compensation common wiring to output a feedback common voltage,
The connecting portion further includes a second connection wiring connected to the feedback common wiring,
The printed circuit board, further comprising a feedback unit for generating a common voltage compensation using the feedback common voltage, and transmitting the generated common voltage to the compensation common wiring.
According to claim 2,
The feedback unit,
A first resistor connected to the second connection wiring;
A second resistor connected to the first resistor and the first connection wiring;
An amplifier in which a non-inverting input terminal is connected to a PCB ground terminal, an inverting input terminal is connected to the first resistor, and an output terminal is connected to the second resistor and the first connection wiring.
Display device comprising a.
The method of claim 3,
The electrostatic discharge unit, a display device including a first discharge diode having an anode connected to the PCB ground terminal and a cathode connected to the output terminal of the amplifier.
The method of claim 4,
The electrostatic discharge unit, the display device further comprises a second discharge diode having an anode connected to the PCB ground terminal and a cathode connected to the first resistor.
The method of claim 3,
The electrostatic discharge unit, a display device including a first discharge diode having an anode connected to a hole ground terminal electrically independent of the PCB ground terminal and a cathode connected to the output terminal of the amplifier.
According to claim 1,
The connection unit is disposed between the ground transmission wiring for transmitting the ground voltage to the display panel, the common transmission wiring for transmitting the common voltage compensation to the first connection wiring, and the ground transmission wiring and the common transmission wiring for the display. Further comprising a constant voltage transmission wiring for transmitting a constant voltage to the panel,
The printed circuit board, the display device further comprises a power supply unit for supplying the common voltage, and a PCB ground terminal for supplying the ground voltage.
The method of claim 7,
The electrostatic discharge unit,
A discharge resistance connected between the constant voltage transmission wiring and the power supply unit;
A discharge capacitor connected between the constant voltage transmission wiring and the PCB ground terminal and an electrically independent hole ground terminal.
Display device comprising a.
The method of claim 8,
The connection unit further includes a gate transfer wiring for transmitting a gate high voltage to the display panel,
The power supply unit supplies the gate high voltage,
The discharge resistance is a display device connected between the gate transfer wiring and the constant voltage transfer wiring.
According to claim 1,
A common electrode and a touch wiring connected to the common electrode are disposed on the display panel,
The display panel displays a video by supplying a common voltage compensation to the touch wiring during the display period, and a display device for detecting a touch by supplying a modulation common voltage to the touch wiring during the touch period.

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