JPH04287022A - liquid crystal display device - Google Patents

Abstract

PURPOSE:To improve the reliability of connection parts between terminals of signal lines and terminals on the side of a driving circuit by making the pitch of at least one terminal larger than that of others in the liquid crystal device where the terminals are to the signal lines through slanting electric conductors. CONSTITUTION:The terminals 2 are connected to the signal lines through the slanting electric conductors 6 and at least one of the terminals 2 is made larger in pitch than others. Namely, the pitch of three terminals in a block A consisting of 10 terminals 2 is set to a=180mum, the pitch of the remaining terminals is set to b=180.5mum, and the pitch between terminals at the end part of the block A is set to a=180mum. When there are 160 terminals of TAB, 16 blocks A are provided and the slanting electric conductors 6 are unchanged. Thus, this liquid crystal device is so constituted that the distance between terminals at both ends at the time of thermocompression bonding is nearly equal to the distance between terminals 2 connected to the end part terminals.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a liquid crystal display device.

0002

2. Description of the Related Art FIG. 2 is a wiring diagram of an equivalent circuit of a display matrix section of an active matrix type liquid crystal display device using thin film transistors and its peripheral circuits. Although this figure is a circuit diagram, it is drawn to correspond to the actual geometrical arrangement. In the figure, AR is a matrix array in which pixels are arranged two-dimensionally. X is a video signal line,
Subscripts G, B, and R are added corresponding to green, blue, and red pixels, respectively. Y is a scanning signal line, and the subscript 1
, 2, 3, . . . , end are added according to the order of scanning timing. The video signal lines X (subscript omitted) are alternately connected to an upper (or odd number) video signal drive circuit He and a lower (or even number) video signal drive circuit Ho. The scanning signal line Y is connected to a vertical scanning circuit V. SUP is 1
Exchange information for the CRT (cathode ray tube) from the power supply circuit and host (upper processing unit) to obtain information for the TFT liquid crystal display device from the power supply circuit and the host (upper processing unit) to obtain stabilized voltage sources obtained by dividing multiple voltages from one voltage source. A circuit that includes a circuit.

FIG. 3 is a perspective view showing a part of a liquid crystal display device. In the figure, 1 is a liquid crystal display cell in which a matrix array AR is formed, 2 is a terminal of a video signal line X and a scanning signal line Y provided in the liquid crystal display cell 1, and 3 is a terminal provided around the liquid crystal display cell 1. 4 is a TAB (Tape Automated) connected to the printed circuit board 3.
Bonding), semiconductor chips for video signal drive circuits He, Ho, and vertical scanning circuit V are mounted on TAB4. 5 is a terminal provided on the TAB 4, and the terminal 5 is connected to the terminal 2 through an anisotropic conductive film. Here, the anisotropic conductive film contains conductive particles such as nickel in an adhesive, and in order to connect the terminals 5 and 2 with the anisotropic conductive film, the liquid crystal display cell 1 and the TAB 4 must be connected. An anisotropic conductive film is provided between them, and by heating to about 190° C. and thermocompression bonding, the conductive particles are crushed and the terminals 5 and 2 are connected by the conductive particles.

FIG. 4 is a schematic diagram showing the terminal portion of a liquid crystal display cell. In the figure, 6 is a diagonal wiring that connects the terminal 2 and the video signal line X.

[0005] In the conventional liquid crystal display device,
The pitch of terminals 5 is made equal to the pitch of terminals 2.

[0006] An active matrix type liquid crystal display device using thin film transistors is, for example, ``12.5-inch active matrix type color liquid crystal display employing redundant configuration'', Nikkei Electronics, Inc.
Pages 193-210, December 15, 1986, published by Nikkei McGraw-Hill.

[0007]

However, in such a liquid crystal display device, when thermocompression bonding is performed to connect the terminals 5 and 2, the TAB4 expands and the TAB
The reliability of the connection between terminal 5 and terminal 2 at the end of B4 is reduced. For example, the amount of thermal expansion during thermocompression bonding is from 0.1 to
0.2%, the pitch of the terminals 5 is 180 μm, and the number of terminals 5 is 160, the distance elongation between the terminals 5 at both ends during thermocompression bonding is 28.8 to 57.6 μm. If the width is 90 μm, the amount of elongation is 30% or more of the width of the terminal 5, so the connection area is reduced.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide a liquid crystal display device in which the reliability of the connection between the terminal of the signal line and the terminal on the drive circuit side is good. do.

[0009]

[Means for Solving the Problems] In order to achieve this object, in the present invention, in a liquid crystal display device in which terminals are connected to signal lines via diagonal wiring, the pitch of at least one of the terminals is changed to another pitch. Make it bigger than.

0010

[Operation] In this liquid crystal display device, the distance between the terminals at both ends on the drive circuit side during thermocompression bonding can be made almost the same as the distance between the terminals of the signal line connected to the end terminals. , the reliability of the connection between the signal line terminal and the drive circuit side terminal is good.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic diagram showing a terminal portion of a signal line of an active matrix type liquid crystal display device using thin film transistors according to the present invention. In this liquid crystal display device, the pitch of three of block A consisting of ten terminals 2 is set to a=180 μm, and the pitch of the remaining six terminals is set to b.
= 180.5 μm. Further, the pitch between the terminals 6 at the ends of the block A is a=180 μm. and,
When the number of terminals 5 of TAB4 is 160, 16 blocks A are provided. Furthermore, the diagonal wiring 6 has not been changed.

In this liquid crystal display device, the distance between the terminals 5 at both ends during thermocompression bonding can be made almost the same as the distance between the terminals 2 connected to the end terminals 5. The reliability of the connection with the terminal 5 is good. That is, since the distance between the terminals 2 to be connected to the terminals 5 at both ends is 30 μm longer than when all pitches are a = 180 μm, for example, as described above, the distance between the terminals 5 at both ends during thermocompression bonding is 30 μm longer.
Even if the amount of distance extension between them is 28.8 to 57.6 μm, the reliability of the connection between the terminals 2 and 5 is good. Also, the pitch of terminal 2 is a=180 μm, b=180
．． 5 μm, even if the minimum grid of computer-aided design (CAD) is 0.5 μm, the second part of the terminal can be designed by computer-aided design, and the second part of the terminal can be designed by computer-aided design. It's easy. Furthermore, since the terminal 2 portion is divided into blocks and the pitches are determined, it is easy to design the terminal 2 portion by computer-aided design. Further, since the diagonal wiring 6 is not changed, design changes can be easily made by computer-aided design.

[0013] In the above embodiment, the case of an active matrix type liquid crystal display device using thin film transistors has been described, but the present invention can also be applied to a simple matrix type liquid crystal display device. Further, in the above embodiment, the terminal on the drive circuit side is T
Although the case where the terminal 5 is formed on AB4 has been described, the present invention can also be applied when the terminal on the drive circuit side is a terminal formed on a flexible printed circuit board or the like.

[0014]

As explained above, in the liquid crystal display device according to the present invention, the distance between the terminals at both ends on the drive circuit side during thermocompression bonding and the distance between the terminals of the signal line connected to the end terminals are Since the distances can be made almost the same, the reliability of the connection between the terminal of the signal line and the terminal on the drive circuit side is good. As described above, the effects of this invention are remarkable.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a terminal portion of a signal line of a liquid crystal display device according to the present invention.

FIG. 2 is a wiring diagram of an equivalent circuit of a display matrix section of an active matrix type liquid crystal display device using thin film transistors and its peripheral circuits.

FIG. 3 is a perspective view showing a part of the liquid crystal display device.

FIG. 4 is a diagram showing a terminal portion of a liquid crystal display cell.

[Explanation of symbols]

2...Terminal 6...Diagonal wiring

Claims (1)

[Claims] 1. A liquid crystal display device in which terminals are connected to signal lines via diagonal wiring, characterized in that the pitch of at least one of the terminals is larger than the pitch of the other terminals.