JPH0219890A - drive circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a drive circuit that can be effectively mounted in high density for use in flat panel displays.

BACKGROUND OF THE INVENTION In recent years, demand for large-capacity display devices has been increasing in the field of information equipment, mainly computers, and the field of video equipment, mainly televisions and video tape recorders (VTRs). ,Liquid crystal displays have attracted particular attention, and the drive circuits that drive these liquid crystal displays are also required to be mounted in high density.

A conventional liquid crystal panel drive circuit will be described below with reference to the drawings.

FIG. 3 shows an example of the configuration of the input/output terminals of a conventional liquid crystal panel drive circuit and the wiring at the time of mounting.

In FIG. 3, 31 is the LSI of the drive circuit, 32 is the output terminal for driving the electrodes of the liquid crystal panel, 33 is the input terminal for the LSI power supply and control signals, 34 is the output terminal lead line, 35
is the lead line of the input terminal. - When it comes to large-capacity liquid crystal panels for boat fishing, the number of electrodes is in the hundreds, and the drive circuit L
Since the SI has about 60 to 80 output terminals, an LSI with a plurality of drive circuits is normally used. Accordingly, each LSI
As shown in Figure 3, it is necessary to use crossover wiring for power supplies and control signals that are commonly used.

(For example, LCD dot matrix segment driver, MSM5299BGS, data book: Oki Electric Industry Co., Ltd.) Therefore, the current mainstream method is to mount the LSI of the drive circuit on a printed circuit board.

However, as liquid crystal panels become larger in capacity and thinner, higher-density packaging becomes necessary, and chip-on-glass mounting (hereinafter referred to as COG mounting), in which the drive circuit LSI is directly mounted on the glass substrate of the liquid crystal panel, becomes necessary. It has become.

Problems to be Solved by the Invention For this reason, the drive circuit having the conventional configuration shown in FIG. 3 requires crossover wiring, which has the problem of complicating implementation.

The present invention provides an effective drive circuit that solves the above problems.

Means for Solving the Problems In order to achieve the above object, the drive circuit of the present invention provides an input terminal for an input signal that is commonly used for each of the drive circuits among the input signals of the plurality of drive circuits. A plurality of pads are provided for each of the same signals, and the pads of each input terminal of the same signal are connected by a low resistance conductor.

By providing a plurality of input terminals for input signals that are used for common functions, crossover wiring is not necessary even in COG mounting, and wiring resistance during mounting can be reduced.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram showing the configuration of a drive circuit in an embodiment of the present invention, where ■ is an LSI chimp, 2 is an output terminal pad,
3 is an input terminal pad, 4 is a common input terminal pad, and 5 is a conductor wiring. The input terminal pad 4 is an input terminal for power and control signals that are common to each chip. By providing input terminals on the left and right sides of each chip, crossovers on the mounting board are unnecessary and wiring between chips is facilitated. Furthermore, since the left and right input terminals are connected with a low resistance conductor,
The overall wiring resistance can be reduced compared to mounting only with wiring on a glass substrate.

Figure 2 shows the wiring at the time of mounting when the drive circuit of the present invention is used as a drive circuit for a liquid crystal panel, 21 is an output terminal lead line, 22 is a common input terminal lead line, and 23 is an input terminal lead line. It is a line.

As is clear from FIG. 2, there is no cross-over wiring and high-density wiring can be achieved. Furthermore, since the resistance of the wiring between common input terminals within a chip can be easily reduced, the resistance of the common wiring part of the mounting wiring can be reduced by shortening the lead wire 22 of the common input terminal. can.

Note that the pad arrangement and number shown in the embodiment of FIG. 1 are only an example and are not limited to this, and the mounting wiring shown in FIG. 2 is also only an example and is not limited to this. .

Effects of the Invention The present invention can eliminate the need for crossover wiring when performing COG mounting in drive circuits that require high-density packaging such as liquid crystal panels, and can achieve the effects of reducing the wiring resistance of the common signal section. It is something. In particular, since the common signal is mainly the power supply, reducing the wiring resistance has an extremely large effect on stabilizing the operation of the drive circuit.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a drive circuit in an embodiment of the present invention,
FIG. 2 is a schematic diagram showing the mounting wiring of a driving circuit in an embodiment of the present invention, and FIG. 3 is a schematic diagram showing mounting wiring of a driving circuit of a conventional liquid crystal panel. ■...LSI, 2...Output terminal pad, 3...Input terminal pad, 4...Common input terminal pad, 5... conductor wiring. Agent's name: Patent attorney Shigetaka Awano 1 person 2 -- Issei p or hitsude high wife 3 --, XVFI is also widely used.

Claims (2)

[Claims] (1) In a drive circuit that uses multiple chips mounted on one substrate, among the input signals of the plurality of drive circuits, the input signal commonly used for each of the drive circuits is The input terminal has multiple pads for each signal,
A drive circuit characterized in that pads of input terminals of the same signal are connected with a low resistance conductor. (2) The drive circuit according to claim (1), wherein the drive circuit is a drive circuit for driving a liquid crystal panel.