KR102235714B1 - Printed circuit board and display device including the same - Google Patents

Abstract

The present invention relates to a printed circuit board and a display device including the same to effectively block electromagnetic interference and to easily discharge static electricity, and are provided on the substrate and disposed to include an outer area of a plurality of image data supply lines. A ground pattern and a plurality of conductive members provided on the ground pattern and electrically connected to the ground pattern may be included.

Description

Printed circuit board and display device including the same {PRINTED CIRCUIT BOARD AND DISPLAY DEVICE INCLUDING THE SAME}

The present invention relates to a display device, and more particularly, to a printed circuit board capable of effectively blocking electromagnetic interference and easily discharging static electricity, and a display device including the same.

Due to the development of electronic communication technology, it is possible to increase the speed and broadband of electronic devices, as well as to drive electronic devices with a small amount of energy. However, electronic devices are sensitive to electromagnetic interference (EMI) and sometimes malfunction due to this.

Accordingly, in the field of a flat panel display (FPD), a method for solving an electromagnetic interference problem is constantly being studied. Representative examples of the flat panel display include a liquid crystal display device (LCD), a plasma display panel device (PDP), a field emission display device (FED), and an electroluminescent display device ( There are Electro Luminescence Display device (ELD), Electro-Wetting Display device (EWD), and Organic Light Emitting Display device (OLED).

As is well known, electromagnetic interference is generated in an electronic device that uses a lot of high-frequency signals as the electric and magnetic fields mixed around the wires propagate into the air when a high-frequency current flows through a certain wire.

In a flat panel display, since a plurality of circuit components mounted on a printed circuit board (hereinafter, referred to as a PCB) operate at a high frequency to generate a driving signal and a driving voltage for driving the display panel, the amount of electromagnetic waves emitted is large. In particular, the image data supply lines formed on the PCB to supply digital image data provided from an external host system to the timing controller transmit signals at an ultra-high frequency and are very vulnerable to electromagnetic interference.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above-described problems, and an object of the present invention is to provide a printed circuit board and a display device including the same, which can effectively block electromagnetic interference and easily discharge static electricity.

In addition to the technical problems of the present invention mentioned above, other features and advantages of the present invention will be described below or will be clearly understood by those of ordinary skill in the art from such technology and description.

The printed circuit board according to the present invention for achieving the above-described technical problem is a ground pattern provided on the substrate and disposed including an outer region of a plurality of image data supply lines, and a ground pattern provided on the ground pattern and It may include a plurality of conductive members electrically connected.

According to the means for solving the above problems, the present invention has the following effects.

According to the present invention, by disposing a conductive member on the PCB to conduct the upper surface of the PCB and the cover shield, electromagnetic interference generated from the PCB may be reduced, and electrostatic discharge (ESD) may be facilitated.

In addition to the effects of the present invention mentioned above, other features and advantages of the present invention will be described below or will be clearly understood by those of ordinary skill in the art from such technology and description.

1 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.
FIG. 2 is an exploded perspective view illustrating a rear surface of the liquid crystal display shown in FIG. 1.
3 is a cross-sectional view illustrating a first region A between the timing controller 40 mounted on the PCB 20 and the connector 50 of the PCB 20.
4 is a plan view showing the first region A.
5 is a cross-sectional view taken along line AA′ of the PCB 20 shown in FIG. 4.

The meaning of the terms described in this specification should be understood as follows. Singular expressions should be understood as including plural expressions unless clearly defined differently in context, and terms such as “first” and “second” are used to distinguish one element from other elements, The scope of rights should not be limited by these terms. It is to be understood that terms such as "comprises" or "have" do not preclude the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. The term “at least one” is to be understood as including all possible combinations from one or more related items. For example, the meaning of “at least one of the first item, the second item, and the third item” means that each of the first item, the second item, or the third item, as well as the first item, the second item, and the third item, It means a combination of all items that can be presented from more than one. The term "on" is meant to include not only a case where a certain structure is formed on the immediate upper surface of another structure, but also a case where a third structure is interposed between these elements.

Hereinafter, a preferred example of a display device according to the present invention will be described in detail with reference to the accompanying drawings.

The display device of the present invention includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an organic light emitting diode display. , OLED), and an electrophoresis display device (Electrophoresis, EPD). In the following embodiments, a liquid crystal display device will be described as an example of a flat panel display device, but it should be noted that the display device of the present invention is not limited to a liquid crystal display device.

1 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 2 is an exploded perspective view illustrating a rear surface of the liquid crystal display of FIG. 1.

Referring to FIG. 1, a liquid crystal display according to an embodiment includes a liquid crystal panel 2, a backlight unit, a board assembly unit driving the liquid crystal panel 2, and a casing member casing them. Includes.

The liquid crystal panel 2 includes a liquid crystal layer formed between two substrates. The substrates may be made of an organic substrate, a plastic substrate, a film substrate, or the like.

The upper substrate 6 of the liquid crystal panel 2 includes a black matrix and a color filter. The lower substrate 4 of the liquid crystal panel 2 includes data lines, gate lines orthogonal to the data lines, and pixels arranged in a matrix form.

Each of the upper substrate 4 and the lower substrate 4 of the liquid crystal panel 2 has a polarizing plate attached to an outer surface thereof, and an alignment layer for setting a pretilt angle of the liquid crystal is formed on an inner surface in contact with the liquid crystal. A spacer is formed between the upper substrate 4 and the lower substrate 4 of the liquid crystal panel 2 to maintain a cell gap of the liquid crystal cell.

The liquid crystal panel 2 has a frame shape and is supported by a guide panel 22 having a stepped portion.

The backlight unit includes light source units 52 and 55, a light guide plate 16, and a plurality of optical sheets 18.

The light source units 52 and 55 include a plurality of LEDs 52 and a light source PCB 55 on which the plurality of LEDs 52 are mounted.

The light guide plate 16 guides the light provided from the plurality of LEDs 52 and emits it to the upper surface, thereby irradiating the light to the rear surface of the liquid crystal panel 2.

The plurality of optical sheets 18 are disposed on the light guide plate 16 to diffuse and condense light emitted from the light guide plate 16 to an upper surface. To this end, the plurality of optical sheets 18 may include a plurality of diffusion sheets and prism sheets.

The board assembly unit is formed on a first circuit film 14 to drive a gate line of the liquid crystal panel 2, and a gate drive IC 12 is formed on the second circuit film 13 to provide the liquid crystal panel. A data drive IC 11 for driving the data line of (2) and a PCB 20 connected to the second circuit film 13 are included.

In the present invention, unlike that shown in FIG. 1, the data drive IC 11 and the gate drive IC 12 can be directly mounted on the liquid crystal panel 2. In addition, the PCB 20 may be configured as a single unit as shown in FIG. 1 to be configured on one side of the second circuit films 13, or the PCB 20 configured on one side of the second circuit films 13 Apart from that, a PCB may be configured on one side of the first circuit film 14.

The casing member is located under the backlight unit, the cover bottom 26 on which the backlight unit and the guide panel 22 are mounted, and a case top located above the liquid crystal panel 2 and having an open front surface. 30 and a cover shield 28 covering the PCB 20 from the rear side of the cover bottom 26.

Meanwhile, when the liquid crystal display according to the embodiment is turned over and looking at the rear surface, as illustrated in FIG. 2, the PCB 20 is attached to the rear surface of the cover bottom 26. In addition, the second circuit film 13 surrounds the side surface of the cover bottom 26 and extends to the rear surface of the cover bottom 26 and is connected to the PCB 20.

A cover shield 28 is disposed on the cover bottom 26. The cover shield 28 is covered by a screw 36 passing through the first hole 32 provided in the cover shield 28 and the second hole 34 provided in the cover bottom 26. It is assembled with the bottom 26.

In particular, in the present invention, by disposing a conductive member 46 on the PCB 20 to conduct the upper surface of the PCB 20 and the cover shield 28, electromagnetic interference generated in the PCB 20 is reduced. , Electrostatic Discharge (ESD) can be facilitated. The detailed description of the conductive member 46 of the present invention is as follows.

3 is a cross-sectional view illustrating a first region A between the timing controller 40 mounted on the PCB 20 and the connector 50 of the PCB 20. 4 is a plan view showing the first region A.

3 and 4, the timing controller 40 is mounted on the PCB 20.

The timing controller 40 includes digital image data (RGB) from an external host system (not shown) through interfaces such as a Low Voltage Differential Signaling (LVDS) interface, a Transition Minimized Differential Signaling (TMDS) interface, and a Display Port (DP) interface. , Vertical/horizontal synchronization signals (Vsync, Hsync), data enable signals (Data Enable, DE), and synchronization signals (SYNC) such as a main clock (CLK) are provided.

The timing controller 40 arranges digital image data RGB provided from the host system and supplies it to the data drive IC 11. In addition, the timing controller 40 outputs a control signal for controlling the driving timing of the data drive IC 11 and the gate drive IC 12 using the synchronization signal SYNC provided from the host system.

A plurality of image data supply lines DP are disposed in the first area A between the pad connected to the connector 50 of the PCB 20 and the timing controller 40.

The plurality of image data supply lines DP transmit digital image data RGB provided from an external host system to the timing controller 40 through the connector 50. The plurality of video data supply lines (DP) is a number of VESA (Video Electronics Standards Association) standards such as LVDS (Low Voltage Differential Signaling) interface, TMDS (Transition Minimized Differential Signaling) interface, DP (Display Port) interface. It can be configured to include lanes (line pairs).

The present invention is generated on the PCB 20 by forming a ground pattern GP in some areas of the PCB 20 including the periphery of the first area A where the plurality of image data supply lines DP are arranged. It reduces electromagnetic interference and facilitates electrostatic discharge. To this end, the ground pattern GP is disposed on the PCB 20 and is disposed in some areas including the second area B, which is both sides of the first area A.

The reason why the ground pattern GP is disposed in the second area B is that the plurality of image data supply lines DP transmit signals at ultra-high frequencies as described above, and are very vulnerable to electromagnetic interference. Because it does.

Meanwhile, the electromagnetic interference is more severe in outermost lines disposed at both ends of the plurality of image data supply lines DP. Accordingly, in the present invention, by disposing the conductive member 46 on the ground pattern GP of the second region B adjacent to the outermost line, electromagnetic interference generated in the periphery of the outermost lines can be effectively reduced. have.

As shown in FIG. 3, the conductive member 46 may be formed of a conductive gasket in which a bottom surface is attached to the ground pattern and an upper surface is in contact with the rear surface of the cover shield. In the present invention, electromagnetic interference generated from a plurality of image data supply lines DP is reduced by conducting the ground pattern GP of the PCB 20 and the cover shield 46 through the conductive member 46. In addition, static electricity generated around the plurality of image data supply lines DP is discharged to the outside through the conductive member 46 and the cover shield 28.

The conductive member 46 of the present invention is not limited to being disposed corresponding to the second area B, and a plurality of conductive members 46 may be disposed in the remaining areas where the ground pattern GP is formed.

5 is a cross-sectional view taken along line A-A' of the PCB 20 shown in FIG. 4.

The PCB 20 may be a substrate in which each of a thin core CCL in which a plurality of signal lines for transmitting the driving signal and the driving voltage are formed on an inner layer raw material are laminated by an interlayer adhesive. The surface of the PCB 20 may be protected by a photo solder resist.

As shown in FIG. 5, the PCB 20 has a ground metal layer L2 formed on the entire surface thereof, and the ground metal layer L2 comprises a plurality of layers L1 and L2 constituting the PCB 20. , L3, ...) is provided on any one layer.

Meanwhile, the ground pattern GP formed on the PCB 20 is electrically connected to the ground metal layer L2 through a plurality of via holes GH. Specifically, the plurality of via holes GH penetrate through the ground pattern GP and the surfaces of the PCB 20 to expose the ground metal layer L2. In addition, a conductive material CM is embedded in the plurality of via holes GH so that the ground pattern GP and the ground metal layer L2 are electrically connected to each other.

Accordingly, according to the present invention, electromagnetic interference generated in the periphery of the plurality of image data supply lines DP is emitted to the outside of the PCB 20 through the plurality of via holes GH and the ground metal layer L2.

On the other hand, unlike the above example, in the present invention, a coupling capacitor is mounted on the ground pattern GP of the second region B instead of a conductive gasket. It is also possible to reduce the electromagnetic interference generated in the.

As described above, in the present invention, by disposing the conductive member 46 on the PCB 20 to conduct the upper surface of the PCB 20 and the cover shield 28, the PCB 20 Generated electromagnetic interference may be reduced, and electrostatic discharge (ESD) may be facilitated.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and that various substitutions, modifications, and changes are possible within the scope of the technical matters of the present invention. It will be obvious to those who have the knowledge of. Therefore, the scope of the present invention is indicated by the claims to be described later, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

40: timing controller 50: connector
GP: Ground pattern GH: Via hole
DP: video data supply line 46: conductive member

Claims (5)

Board;
A timing controller mounted on the substrate;
A plurality of image data supply lines provided on the substrate and connecting between the timing controller and a connector connected to an external host system;
A ground pattern provided on the substrate and disposed in an outer area of the plurality of image data supply lines; And
It includes a plurality of conductive members provided on the ground pattern and electrically connected to the ground pattern,
At least a portion of the ground pattern extends parallel to the length direction of the plurality of image data supply lines,
The plurality of conductive members are disposed on the ground pattern adjacent to outermost lines among the plurality of image data supply lines. The method of claim 1,
The plurality of conductive members
A printed circuit board disposed in second regions on both sides of the first region in which the plurality of image data supply lines are provided. The method of claim 1,
A plurality of via holes penetrating the ground pattern and the surface of the printed circuit board to expose the ground metal layer inside the substrate; And
A printed circuit board further comprising a conductive material buried in the plurality of via holes to connect the ground pattern and the ground metal layer. The printed circuit board according to any one of claims 1 to 3; And
A display device including a cover shield covering the printed circuit board. The method of claim 4,
The conductive member is
A display device including a conductive gasket having a bottom surface attached to the ground pattern and an upper surface contacting a rear surface of the cover shield.

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