JPH0634987A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To simplify the structure of the above device and to reduce its cost by arraying the segment output of a driver IC packaged on a tape automated bonding(TAB) tape and a common output in the connecting terminal array of the TAB tape and integrally connecting the tape to the liquid crystal display element. CONSTITUTION:The liquid crystal display element 1 is mechanically and electrically connected by an anisotropically conductive film 5 to the TAB tape 8 packaged with the driver IC 7. As a result, the segment output voltages are transmitted from the driver IC 7 to the patterns of of the TAB tape 8 and are transmitted via the anisotropically conductive film 5 to segment electrodes 2. On the other hand, the common output voltage is transmitted from the driver IC 7 to the patterns of the TAB tape 8, are once transmitted to segment terminals 6 via the anisotropically conductive film 5 and are transmitted to an opposite common electrode 3 by a vertical conducting agent 4. The liquid crystal display device is constituted by integratedly connecting the TAB tape to the liquid crystal display in such a manner, by which the need for printed circuit boards is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device which serves as a display portion of a pager, a handy terminal or the like.

[0002]

2. Description of the Related Art In a conventional liquid crystal display device, a package 16 in which an IC chip is mounted on a TAB as shown in FIG. 3 or a package 16 in which an ordinary lead frame is wire-bonded is a printed wiring board 15 (hereinafter abbreviated as PCB). It was soldered to and was connected to the liquid crystal display element 1 by a rubber connector 14 or a thermocompression flexible connector (hereinafter referred to as heat seal). Alternatively, as shown in FIG. 4, the segment TAB tape 17 and the common TAB tape 18 were connected to the liquid crystal display element by the anisotropic conductive film 5. Here, the liquid crystal display element refers to a portion in which liquid crystal is sandwiched by a pair of electrodes, and the liquid crystal display device refers to the entire portion including a driver portion.

[0003]

The prior art described above necessarily requires a PCB as shown in FIG. 3, and a rubber connector or heat seal is required for connection with the liquid crystal display element. Alternatively, at least two types of TAB tapes are required as shown in FIG. Therefore, the structure becomes complicated, the number of parts increases, and the cost becomes high. Therefore, the present invention solves such a problem, and an object of the present invention is to provide a low-cost liquid crystal display device with a simplified structure.

[0004]

In the liquid crystal display device of the present invention, one driver IC is subjected to tape automated bonding (hereinafter abbreviated as TAB), and both the segment output and the common output are connected to one side of the TAB tape. It is characterized in that it is connected to the liquid crystal display element at a time by pulling out and arranging it.

[0005]

The segment output and the common output of the driver IC mounted on the TAB tape are arranged in the connection terminal row on one side of the TAB tape, and are connected to the liquid crystal display element by the anisotropic conductive film or the like. The connection to the electrode facing the connected electrode is made by a vertical conducting agent or the like.

[0006]

【Example】

[Embodiment 1] An embodiment of the present invention will be described with reference to FIG. For ease of explanation, the number of segment electrodes is 5, and the number of common electrodes is 3. Needless to say, the number and shape of these electrodes can be arbitrarily selected according to the product. The liquid crystal display element 1 is mechanically and electrically connected to the TAB tape 8 on which the driver IC 7 is mounted and the anisotropic conductive film 5.

Then, the segment output voltage is the driver I
It is transmitted from C7 to the pattern of the TAB tape 8 and is transmitted to the segment electrode 2 through the anisotropic conductive film 5. The common electrode 3 is shown by a solid line because it is on the front side in FIG. 1, and the segment electrode 2 is shown by a broken line because it is on the back side. On the other hand, the common output voltage is transmitted from the driver IC 7 to the pattern of the TAB tape 8 and is once transmitted to the segment terminal 6 via the anisotropic conductive film 5. Then, it is transmitted to the opposing common electrode 3 by the vertical conducting agent 4. TAB tape 8
Is arranged in a plane (0 °) with the liquid crystal display device.
The flexibility which is the characteristic of the AB tape may be used to bend and arrange it by 90 ° or 180 °.

[Embodiment 2] Another embodiment of the present invention will be described with reference to FIG. In the first embodiment, the driver IC 7 has both a segment output and a common output, but in FIG. 2, the driver ICs 10 and 1 each have a single type of output.
A combination of 1 and 12 is used. Driver I
C10 has only segment output and driver IC1
1 and 12 have only common output. The liquid crystal display element 1 is mechanically and electrically connected by the anisotropic conductive film 5 to the TAB tape 8 on which the driver ICs 10, 11 and 12 are mounted.

In addition to the embodiments described here, various combinations can be applied to individual products.

[0010]

As described above, the liquid crystal display device has TA
Since the liquid crystal display device is constructed by connecting the B tapes at once, the PCB is unnecessary. Even if a plurality of conventional TAB tapes are used, the number of TAB tapes can be reduced to half, and the number of parts can be reduced. Therefore, the cost of parts and man-hours can be reduced and an inexpensive liquid crystal display device can be realized. It also has the advantage of being small, lightweight and thin.

[Brief description of drawings]

FIG. 1 is a plan view of a first embodiment in which one driver IC is used in a liquid crystal display device of the present invention.

FIG. 2 is a plan view of a second embodiment in which a plurality of driver ICs are used in the liquid crystal display device of the present invention.

FIG. 3 is a sectional view of a liquid crystal display device using a conventional rubber connector.

FIG. 4 is a plan view of a liquid crystal display device using two types of conventional TAB tapes.

[Explanation of symbols]

1. Liquid crystal display device 2. Segment electrode 3. Common electrode 4. Vertical conduction agent 5. Anisotropic conductive film 6. Segment terminal 7. Driver IC (for both common and segment) 8. TAB tape 9. Input terminal 10. Segment driver IC 11. Common driver IC 12. Common driver IC 13. Holding frame 14. Rubber connector 15. PCB 16. Package (TAB mounting or lead frame +
Wire bonding) 17. TAB tape for segment 18. Common TAB tape 19. TAB input terminal for segment 20. TAB input terminal for common

Claims (2)

[Claims] 1. A driver IC is tape-automated bonded (hereinafter abbreviated as TAB), and both the segment output and the common output are drawn out and arranged in a connection terminal row on one side of the TAB tape, and are collectively connected to a liquid crystal display element. A liquid crystal display device characterized by the above. 2. A liquid crystal display device according to claim 1, wherein a plurality of driver ICs are mounted on the TAB.