TWI793323B - Printed circuit board and display device having the same - Google Patents

Abstract

According to an aspect of the present invention, there is provided a printed circuit board included in a display device, the printed circuit board comprising: a rigid region and a flexible region; a flexible insulating layer included in the rigid region and the flexible region; and a rigid insulating layer laminated on the flexible insulating layer to be included in the rigid region, wherein a conductive pattern for detecting touch is formed in the flexible region, and wherein a connection pad is formed in the rigid region for mounting an electronic element.

Description

Printed circuit board and display device having same

The present application relates to a printed circuit board and a display device with the printed circuit board.

As display devices become thinner and the size of bezels becomes smaller, a structure in which electronic components such as driving integrated circuits (ICs) for driving the display device are mounted on the glass of the display The substrate is attached to a flexible substrate, etc. rather than a glass substrate.

In Korean Patent Publication No. 10-2005-0029042 (October 13, 2006), a method for manufacturing a build-up type (build by via fill plating and belt sanding) is disclosed. -up) printed circuit board (PCB) approach.

According to an aspect of the present invention, there is provided a printed circuit board included in a display device, the printed circuit board includes: a rigid area and a flexible area; a flexible insulating layer is included in the rigid area and the flexible area and a rigid insulating layer laminated on the flexible insulating layer to be contained in the rigid region, wherein in the flexible region a A conductive pattern for detecting touch is formed, and a connection pad for installing electronic components is formed in the rigid area.

According to another aspect of the present invention, a display device is provided, which includes: a display panel; and a printed circuit board electrically connected to the display panel, wherein the printed circuit board includes: a rigid area and a flexible area; a flexible insulating layer contained in the rigid region and the flexible region; and a rigid insulating layer laminated on the flexible insulating layer to be contained in the rigid region, wherein in the flexible region A conductive pattern for detecting touch is formed, and electronic components are installed on the rigid area.

1: Display panel

2: frame

3: cover glass

10: Printed circuit board

100, 300: Flexible insulating layer

200: Rigid insulation

400: protective layer

500: electronic components

500a: Power management IC (PMIC)

500b: Fingerprint on Display (FOD) IC

500c: Display Driver IC (DDI) / Touch Display Driver IC (TDDI)

500d: passive device

600: connection plate

600', P ₀ , P ₂ , P ₂ ': circuit pattern

A: part

B: battery

C: connector

F1: Flex Zone/First Flex Zone

F2: Second flexible zone

M: Motherboard

P, P ₀ ': connection pad

P ₁ : Conductive pattern for touch detection

P ₁ ': connecting part

R: rigid zone

SB: Solder component

U: unit pattern

FIG. 1 is a diagram illustrating a printed circuit board according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a printed circuit board according to an embodiment of the present invention.

FIG. 3 is a diagram showing an enlarged view of part A in FIG. 2 .

FIG. 4 is a diagram illustrating a display device according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating a printed circuit board according to another embodiment of the present invention.

FIG. 6 is a diagram illustrating a printed circuit board according to another embodiment of the present invention.

FIG. 7 is a diagram illustrating a display device according to another embodiment of the present invention.

FIG. 8 is a diagram illustrating a display device according to still another embodiment of the present invention.

In the following, various embodiments of a printed circuit board according to the present invention and a display device comprising the same will be explained in detail with reference to the accompanying drawings, in which those presented with the same reference numerals regardless of the figure number The components are the same or correspond and will not be described again.

Although terms such as "first" and "second" may be used to describe various components, such components are not necessarily limited by the above terms. The above terms are only used to distinguish one component from another.

When an element is described as being "connected," "coupled" or "coupled" to another element, the element should be construed as being directly connected, coupled, or bonded to the other element, but may also be in-between. has another element.

The terms used in this description are intended to illustrate certain embodiments only, and should by no means limit the invention. Expressions in the singular include the plural unless expressly used otherwise. In this specification, expressions such as "comprising" or "consisting of" are intended to indicate characteristics, numbers, steps, operations, elements, parts or combinations thereof, and should not be interpreted as excluding one or more other characteristics, Existence or possibility of number, steps, operations, elements, parts or combinations thereof.

A printed circuit board

1 and 2 are diagrams illustrating a printed circuit board according to an embodiment of the present invention. FIG. 3 is a diagram showing an enlarged view of part A in FIG. 2 .

1 and 2, a printed circuit board 10 according to an embodiment of the present invention is a board for driving a display device and includes a rigid region R and a flexible region F1. The printed circuit board 10 is a rigid-flex board in which the rigid region R and the flexible region F1 are integrally formed continuously. Such an integrally formed rigid-flex board is distinguished from a board formed by separately forming a rigid board and a flexible board and then combining these boards by welding or the like. The printed circuit board 10 includes a flexible insulating layer 100 and a rigid insulating layer 200 .

The rigid region R is a part whose deflection is smaller than that of the flexible region F1, and the flexible region F1 is a part that is more flexible than the rigid region R, and at least a part of the flexible region F1 is bendable. As shown in FIG. 1 , the thickness of the flexible region F1 may be smaller than the thickness of the rigid region R. As shown in FIG.

The rigid region R includes the flexible insulating layer 100 and the rigid insulating layer 200 , and the flexible region F1 includes the flexible insulating layer 100 but does not include the rigid insulating layer 200 .

The flexible insulating layer 100 is formed of a flexible and insulating material (for example, an insulating material including polyimide (PI), liquid crystal polymer (LCP), etc.). The flexible insulating layer 100 is included in the rigid region R and the flexible region F1.

The rigid insulating layer 200 may be made of a relatively low-deflection insulating material, such as an insulating material including epoxy. In particular, the insulating material including epoxy resin may include fiber reinforced material such as glass fibers, and such insulating material may be a prepreg. Insulation materials including epoxy resins may also include inorganic fillers.

The rigid insulating layer 200 may be formed on a predetermined area of the flexible insulating layer 100 . A predetermined region in which the rigid insulating layer 200 is formed becomes a rigid region R. Referring to FIG. That is, the rigid insulating layer 200 is laminated on the flexible insulating layer 100 to be included in the rigid region R. Referring to FIG.

The number of flexible insulating layers 100 and the number of rigid insulating layers 200 included in the rigid region R may be plural, respectively. The number of flexible insulating layers 100 included in the flexible region F1 can also be plural. In this case, a plurality of rigid insulating layers 200 and a plurality of flexible insulating layers 100 may be alternately laminated.

The flexible insulating layer 100 may be located outside the rigid insulating layer 200 . In this case, the flexible insulating layer 100 may be located on the outermost layer (the outermost layer does not include the protective layer 400 to be described later).

For example, the flexible insulating layer 100 and the flexible insulating layer 300 may be formed on two surfaces of the rigid insulating layer 200 as shown in FIG. 1 . Here, only one of the two flexible insulating layers 100 and the flexible insulating layer 300 may be included in the flexible region F1 . In this case, only the flexible insulating layer 300 located in the rigid region R is formed to be symmetrical in thickness with respect to the flexible insulating layer 100 contained in the rigid region R and the flexible region F1, so that the flexible insulating layer 300 can participate in the control of warpage.

The flexible area F1 and the rigid area R may include conductive patterns formed on each insulating layer. Such conductive patterns can perform electrical signal transmission.

A conductive pattern P ₁ for detecting touch may be formed in the flexible region F1 , and a connection pad P may be formed in the rigid region R as a conductive pattern for mounting the electronic component 500 . The electronic component 500 may be mounted on the connection pad P by using the solder member SB. The electronic component 500 can be mounted on the rigid region R to implement a chip on board (COB).

The conductive pattern _P1 for touch detection is a conductive pattern for touch detection when a touch is made to a display panel connected to a printed circuit board in a display device. Detecting a touch refers to identifying the position, intensity, area, etc. of a touch. The conductive pattern P ₁ for detecting touch transmits the electrical signal achieved by touch to the electronic device 500 .

The electronic component 500 can be an integrated circuit, such as a touch controller IC, a power management IC (power management IC, PMIC), a fingerprint on display (fingerprint on display, FOD) IC, a display driver IC (display driver IC, DDI), Touch display driver IC (touch display driver IC, TDDI), etc. Multiple electronic components can be formed.

The electronic component 500 may further include passive components such as capacitors. In FIGS. 2 and 6, a PMIC 500a, an FOD IC 500b, a DDI (or TDDI) 500c, and a passive device 500d are shown, but the present invention is not limited thereto.

The conductive pattern _P1 for touch detection can be electrically connected to the electronic device 500 through the connection pad P. Referring to FIG. The electronic device 500 can process the electrical signal transmitted from the conductive pattern P ₁ for detecting touch to extract the position, intensity, area, etc. of the touch. In addition, according to the FOD IC, it is possible to perform fingerprint recognition through the display.

The electronic device 500 can process electrical signals in various ways according to touch detection methods (capacitance method, optical method, ultrasonic method, etc.).

The conductive pattern _P1 for detecting touch may include a plurality of unit patterns U. The unit pattern U may have various patterns such as an angled spiral, a curved spiral, a lattice, and the like. Each unit pattern U may be connected to a connection pad P. Referring to FIG.

2 is a schematic diagram showing a plurality of unit patterns U of the conductive pattern _P1 for touch detection and a connection part _P1 ' as a conductor connecting the unit patterns U and the connection pads P. Referring to FIG. That is, one end of the connection portion P ₁ ′ is connected to one end of the unit pattern U, and the other end of the connection portion P ₁ ′ is connected to the connection pad P. Referring to FIG. The connection parts _P1 ' connect each unit pattern U with the connection pads P, but only some of the connection parts are shown in FIG. 2 .

Referring to FIG. 3 , the unit pattern U of the conductive pattern P ₁ for detecting touch may be formed of a linear conductor line, and the linear conductor line may be connected to the connection part P ₁ ′. The linear conductor lines may be formed in various patterns such as angled spirals, curved spirals, lattices, and the like.

The conductive pattern _P1 for touch detection can be formed of metal such as copper, and can be formed of a plating layer. That is, the linear conductor wires of the unit pattern U may be copper wires. This is in contrast to patterns printed with metal paste.

The conductive pattern _P1 for detecting touch can be formed in the flexible insulating layer 100 in the flexible region F1. In this case, the flexible insulating layer 100 on which the conductive pattern _P1 for detecting touch is formed may be located on the outermost layer of the printed circuit board (the outermost layer among the insulating layers outside the protective layer 400 ).

In the case where the circuit pattern _P0 is formed in the rigid region R and the circuit pattern _P0 in the rigid region R is composed of a plurality of layers, the circuit pattern _P0 formed in different layers is electrically connected by a via hole. Some circuit patterns P ₀ on the outermost layer become connection pads P ₀ ′ for electrically connecting with another substrate.

Some of the circuit patterns P ₀ on the outermost layer in the rigid region R may serve as connection pads P, and the connection pads P are disposed corresponding to the electrodes of the electronic component 500 . Connection pads P may be formed on the outermost layer in the rigid region R and on the flexible insulating layer 100 . The flexible insulating layer 100 on which the connection pads P are formed may be formed on the outermost layer of the printed circuit board (the outermost layer among the insulating layers outside the protective layer 400 ).

The circuit pattern P ₀ on the outermost layer in the rigid region R is covered by the passivation layer 400 , while the connection pads P and P ₀ ′ are exposed by the passivation layer 400 .

The conductive pattern P ₁ and the connecting portion P ₁ ′ for detecting touch on the flexible insulating layer 100, and the circuit pattern P ₀ on the outermost layer in the rigid region R can be formed together by the same circuit forming process and also may have substantially the same thickness.

The protective layer 400 is a layer that protects the outermost conductive pattern of the printed circuit board. The protection layer 400 may be formed in the rigid region R to expose the connection pads P and P ₀ ′, but may cover and protect other circuit patterns P ₀ . The protective layer 400 in the rigid region R may be solder resist.

The protective layer 400 may be formed in the flexible region F1 to cover and protect the conductive pattern P ₁ for detecting touch. The protective layer 400 in the flexible region F1 may be made of a material different from that of the protective layer 400 in the rigid region R. Referring to FIG. Specifically, the protective layer 400 formed in the flexible region F1 may be a coverlay made of flexible and bendable material. Alternatively, the protective layer 400 formed in the flexible area F1 may be formed of ink, and in this case, the flexible area F1 may be bendable.

The protective layer 400 is not necessary and thus can be omitted if necessary.

In FIG. 2 , the protective layer 400 is shown only in the rigid region R, and the protective layer in the flexible region F1 is not shown.

5 and 6 are diagrams illustrating a printed circuit board according to another embodiment of the present invention.

Referring to FIG. 5 and FIG. 6 , in the printed circuit board 10 , the flexible area includes a first flexible area F1 and a second flexible area F2 . The first flexible area F1 and the second flexible area F2 respectively extend from the rigid area R along different directions.

The flexible insulating layer 100 is included in the rigid region R, the first flexible region F1 and the second flexible region F2, while the rigid insulating layer 200 is only included in the rigid region R. That is, the flexible insulating layer 100 is formed on the rigid region R, the first flexible region F1 and the second flexible region F2, and the rigid insulating layer 200 is laminated on a predetermined portion of the flexible insulating layer 100 to be included in In the rigid region R.

A conductive pattern P1 for detecting touch is formed in the first flexible region F1, and a circuit pattern P ₀ and a connection pad P for mounting an electronic component 500 are formed in the rigid region R. A circuit pattern P ₂ is formed in the second flexible region F2 , and a part of the circuit pattern P ₂ is connected to the circuit pattern P ₀ . The second flexible region F2 is bendable, and the circuit pattern _P2 can electrically connect the electronic component 500 with the display panel 1 (see FIG. 7 ). Here, a portion P ₂ ′ of the circuit pattern P ₂ is coupled to the display panel 1 (see FIG. 7 ).

The circuit pattern _P2 in the second flexible region F2 may have a finer pitch than the circuit pattern _P0 in the rigid region R. The circuit pattern _P2 in the second flexible region F2 can be formed by the MSAP method, but the present invention is not limited thereto.

The protection layer 400 may be formed in all the rigid regions R, the first flexible region F1 and the second flexible region F2. The protection layer 400 formed in the rigid region R exposes the connection pads P, but covers and protects other conductive patterns. The protective layer 400 formed in the first flexible area F1 and the second flexible area F2 may be a cover film made of a flexible and bendable material, which may be used for The protective layer 400 in the rigid region R is made of different materials.

The protective layer 400 in the first flexible region F1 can cover and protect the conductive pattern P ₁ used for touch detection, and the protective layer 400 in the second flexible region F2 can protect the circuit pattern P ₂ . However, the protection layer 400 formed in the second flexible region F2 exposes a portion of the circuit pattern _P2 , and the exposed circuit pattern _P2 ' may be coupled to the display panel 1 (see FIG. 7).

The protective layer 400 is not necessary and thus can be omitted if necessary.

In FIG. 6 , the protective layer 400 is only shown in the rigid region R and the second flexible region F2 , and the protective layer in the first flexible region F1 is not shown.

display device

FIG. 4 is a diagram illustrating a display device according to an embodiment of the present invention.

Referring to FIG. 4 , a display device according to an embodiment of the present invention includes a display panel 1 and a printed circuit board electrically connected to the display panel 1 . The electronic component 500 is mounted on the rigid region R of the printed circuit board to drive the display panel 1 .

The display panel 1 can be a light emitting diode (light emitting diode, LED) panel, an organic light emitting diode (organic light emitting diode, OLED) panel, an electrophoretic display panel, an electrochromic display (electrochromic display, ECD), etc. Able to convert electrical signals into visual signals. The display panel 1 can also be a touch screen panel.

The display device may include a frame 2 disposed on a rear surface of the display panel 1, and the frame 2 may support the display panel 1, a printed circuit board, and the like. The frame 2 can be made of metal material or plastic material with excellent thermal conductivity, but the present invention is not limited thereto.

In addition, the display device may further include a cover glass 3 on the front surface of the display panel 1 , and the cover glass 3 can protect the display panel 1 .

The printed circuit board in this embodiment can be understood as the printed circuit board 10 described with reference to FIGS. 1 and 2 . Repeated content will not be repeated.

The display panel 1 and the printed circuit board 10 can be coupled by the connecting board 600 . The connecting board may be a flexible board and may be formed of a flexible insulating layer. The connecting board may include a circuit pattern 600', and one end of the circuit pattern 600' may be bonded to the rigid region R by soldering of the solder member SB, and the other end of the circuit pattern 600' may be bonded by soldering of the solder member SB. Combined with display panel 1.

A printed circuit board may be disposed on the rear surface of the display panel 1 . The connecting plate 600 is bent and disposed on the rear surface, the side surface and the front surface of the display panel 1 . However, since the area covered by the connection plate at the front surface is small, the size of the bezel can be small. Specifically, when the DDI is mounted on the rigid region R as in the present invention, the bezel can be reduced compared to a case where a DDI for driving the display panel 1 is mounted on the display panel 1 .

The flexible region F1 is at least partially bent and disposed on the rear surface of the display panel 1 . Here, the flexible area F1 is positioned closer to the display panel 1 than the rigid area R is. Since the electronic component 500 is installed on the rigid region R and the electronic component 500 protrudes from the upper surface of the rigid region R, the gap between the upper surface of the rigid region R and the rear surface of the display panel 1 is equal to or greater than the height of the electronic component 500 . However, since the electronic component 500 is not mounted on the flexible area F1 and the flexible area F1 is flexible, the flexible area F1 can be bent toward the rear surface of the display panel 1 to be closely attached to the rear surface of the display panel 1. back surface. In this case, the space under the flexible area F1 can be ensured as much as possible while the flexible area F1 is bent. This space may be further occupied by the battery B of the electronic device in which the display device is installed.

FIG. 7 is a diagram illustrating a display device according to another embodiment of the present invention.

Referring to FIG. 7 , a display device according to another embodiment of the present invention includes a display panel 1 and a printed circuit board electrically connected to the display panel 1 . The electronic component 500 is installed in the rigid region R of the printed circuit board to drive the display panel 1 .

The printed circuit board in this embodiment can be understood as the printed circuit board described with reference to FIGS. 5 and 6 . Repeated content will not be repeated.

One end of the circuit pattern _P2 of the second flexible region F2 is soldered to the display panel 1 through the solder member SB, so that the second flexible region F2 is coupled with the display panel 1 .

The rigid region R and the first flexible region F1 may be disposed on the rear surface of the display panel 1 . The second flexible region F2 is bent and disposed on the rear surface, the side surface and the front surface of the display panel 1 . However, since the area covered by the second flexible region F2 on the front surface of the display panel 1 is small, the size of the bezel can be reduced.

The flexible region F1 is at least partially bent and disposed on the rear surface of the display panel 1 . Here, the flexible area F1 is positioned closer to the display panel 1 than the rigid area R is. Since the electronic component 500 is installed on the rigid region R and the electronic component 500 protrudes from the upper surface of the rigid region R, the gap between the upper surface of the rigid region R and the rear surface of the display panel 1 is equal to or greater than the height of the electronic component 500 . However, since the electronic component 500 is not mounted on the flexible area F1 and the flexible area F1 is flexible, the flexible area F1 can be bent toward the rear surface of the display panel 1 to be closely attached to the rear surface of the display panel 1. back surface. In this case, the space under the flexible area F1 can be ensured as much as possible while the flexible area F1 is bent. This space may be further occupied by the battery B of the electronic device in which the display device is installed.

Since the first flexible region F1, the rigid region R and the second flexible region F2 are integrally formed differently from the aforementioned embodiments, they are identical to the rigid region R and the display panel as shown in the previous embodiments. A better mechanical and electrical connection is ensured compared to coupling using a separate connection plate. Since the separate connection board is bonded to the display panel by the solder member, electrical noise may occur at the bonding area between the solder member and the display panel. However, in this example there is no such binding region, And thus electrical reliability can be improved. In addition, depending on the curvature of the connection plate, stress may be concentrated on the bonding area between the solder member and the display panel, and thus, the connection plate may fall off. However, even if the second flexible area F2 is bent, the mechanical stability of the connection is enhanced because the second flexible area F2 is not separated from the rigid area R in this embodiment.

FIG. 8 is a diagram illustrating a display device according to still another embodiment of the present invention.

Referring to FIG. 8 , a printed circuit board included in the display device may be connected to the main board M. Referring to FIG. In this case, the printed circuit board can be disposed between the main board M and the display panel 1 .

The printed circuit board can be connected to the main board M through the connector C. The connecting member C may be formed of flexible material, and may extend from the first flexible region F1. That is, the flexible insulation layer 100 of the first flexible region F1 protrudes to provide the connector C. Referring to FIG.

A pad connected to the main board M is disposed at one end of the connector C, and the pad can be electrically connected to the electronic component 500 mounted on the rigid region R through a circuit wire. The circuit lines are formed on the rigid region R and the first flexible region F1. One end of the circuit wire is connected to the connection pad on which the electronic component 500 is mounted, and the other end of the circuit wire is connected to the pad of one end of the connector C. Referring to FIG. The pads at the one end of the connector C can be combined with the circuit of the main board M. As shown in FIG.

The spirit of the present invention has been described above by way of examples, and those skilled in the present invention can modify, change and replace the present invention in various ways without departing from the essential characteristics of the present invention. Therefore, the exemplary embodiments disclosed in the present invention and the accompanying drawings are not limited but illustrate the spirit of the present invention, and the scope of the present invention is not limited by the exemplary embodiments and the accompanying drawings. The scope of the invention shall be patented by the following applications It should be construed in terms of scope, and it should be construed that all the spirits equivalent to the claims of the following claims belong to the scope of the present invention.

10: Printed circuit board

100, 300: Flexible insulating layer

200: Rigid insulation

400: protective layer

500: electronic components

F1: Flex Zone/First Flex Zone

P: connection pad

P ₀ : circuit pattern

P ₁ : Conductive pattern for touch detection

R: Rigid zone

SB: Solder component

Claims (16)

A printed circuit board included in a display device, the printed circuit board comprising: a rigid region and a flexible region; a flexible insulating layer contained in the rigid region and the flexible region; and a rigid insulating layer, a layer pressed on the flexible insulating layer to be included in the rigid area, wherein a conductive pattern for detecting touch is formed only in the flexible area, and wherein a conductive pattern for mounting is formed in the rigid area Connection pads for electronic components. The printed circuit board as described in item 1 of the patent scope, wherein the conductive pattern for detecting touch is formed on the flexible insulating layer in the flexible region. The printed circuit board according to claim 1, wherein the connection pad is formed on the flexible insulating layer in the rigid area. The printed circuit board as described in item 2 or item 3 of the patent scope of the application, wherein the flexible insulating layer is located outside the rigid insulating layer. The printed circuit board as described in item 1 of the patent scope, wherein the conductive pattern for detecting touch includes a plurality of unit patterns, and each of the plurality of unit patterns is electrically connected to the connection pad. The printed circuit board as described in item 1 of the patent scope, wherein the conductive pattern for detecting touch is formed by a plating layer. The printed circuit board as described in item 1 of the scope of the patent application, wherein the flexible The rigid area includes a first flexible area and a second flexible area extending from the rigid area in different directions, and the conductive pattern for detecting touch is formed in the first flexible area. A display device, comprising: a display panel; and a printed circuit board electrically connected to the display panel, wherein the printed circuit board includes: a rigid area and a flexible area; a flexible insulating layer is included in the rigid area and the in the flexible region; and a rigid insulating layer laminated on the flexible insulating layer to be included in the rigid region, wherein a conductive pattern for detecting touch is formed in the flexible region, And wherein electronic components are mounted on the rigid area. The display device according to claim 8 of the patent application, wherein the conductive pattern for detecting touch is formed on the flexible insulating layer in the flexible region. The display device according to claim 8, wherein the electronic components are formed on the flexible insulating layer in the rigid region. The display device according to claim 9 or claim 10, wherein the flexible insulating layer of the printed circuit board is located outside the rigid insulating layer. The display device as described in item 8 of the scope of the patent application, wherein the conductive pattern for detecting touch includes a plurality of unit patterns, and each of the plurality of unit patterns is electrically connected to the electronic element. The display device as described in item 8 of the scope of the patent application, wherein the The conductive pattern for detecting touch is formed by the plating layer. The display device as described in item 8 of the patent scope of the application, wherein the flexible area includes a first flexible area and a second flexible area extending from the rigid area in different directions, wherein the A touch conductive pattern is formed in the first flexible area, and wherein the second flexible area is coupled to the display panel. The display device according to claim 14 of the patent scope, wherein the first flexible region and the rigid region are disposed on the rear surface of the display panel, and the second flexible region is bent and coupled to the front surface of the display panel. The display device according to claim 15, wherein the first flexible region is closer to the display panel than the rigid region.

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