JPS6371890A - Inspection construction for multi-output drive circuit substrate - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a test structure for a multi-output drive circuit board having a plurality of output terminals.

(Prior Art) When displaying information such as television broadcasting using an electro-optical element such as an i-crystal, a method is used in which a plurality of signal lines and scanning lines are formed in a matrix.

The peripheral drive circuit board for driving the signal lines and scanning lines must have several output terminal groups per 1M in order to increase the resolution of the displayed image.

FIG. 5 is a schematic diagram showing an example of this type of multi-output drive circuit board. In the figure, the board (10) has an IC (11
) is mounted, and is connected by a wiring pattern (14) to an input terminal (12) for operating the circuit and an output terminal (13) for electrical connection to a display portion constituting a pixel. Conventionally, a signal similar to the actual driving signal is input to the input terminal (12), and the output terminal (13) is brought into contact with a group of 14 probes formed in the same number and at the same pitch. will be inspected.

FIG. 6 is a diagram schematically showing an example of this inspection structure.

In the figure, the input terminal (12) is connected to the input signal generation circuit (20) for operating the drive circuit board, and the output terminal (13) is connected to the anisotropic conductive rubber (21) and the output terminal (13). A group of probes (2
2) and a probe selection circuit (23) composed of a relay or non-contact switch, etc., to an external output monitor terminal (24). This is the output terminal (13)
By pressing the anisotropically conductive rubber (21) with the probe group (22), an electrical connection can be established between the substrate (1G) and the probe 1 (22).

By monitoring and switching the terminal to be monitored in the probe selection circuit (23), all output terminals (13)
It is possible to inspect the operation of the entire drive circuit board.

(Problems to be Solved by the Invention) However, in this structure, several hundred probe groups (22) may be formed at a pitch of several per meter, so the structure of the probe group (22) is precisely processed. is required. Also, f'! alignment of the output terminal (13) and the probe group (22)!
The process is time consuming and requires expensive inspection equipment.

This invention simplifies the construction of a multi-output drive circuit board for inspection and improves the efficiency of inspection work.

[Structure of the Invention] (Means for Solving the Problems) This invention reduces the number of required probe parts to one, which is the same number as the output terminals of the drive circuit board, and connects the probe parts with a dielectric between this and the output terminals. It has a body. The drive circuits to be inspected here are drive circuits that do not output in-phase or sample-and-hold drive circuits; in the case of sample-and-hold circuit boards, unique data is always output from only one terminal;
Data is input so that the remaining outputs are all sampled at a constant potential.

(Function) By limiting the inspection target and input signal conditions in this way, it is possible to inspect all output terminals with a simple structure, and since one probe is sufficient, the output terminal This makes positioning the probe part easier.

(Example) The details of this invention will be explained below with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention. In the figure, a substrate (31) equipped with a drive circuit (30) has an input terminal (32) and a plurality of, for example, n output terminals (33), which are connected to the drive circuit (30) and the wiring pattern. (34). The input terminal (32) is connected to an input signal generation circuit (35) for operating the drive circuit board, and the output terminal (33) is connected to a dielectric (36) and one probe electrode (37). ) via
It is electrically AC connected to the output monitor terminal (38). FIG. 2 is a diagram showing the configuration of FIG. 1 as an electrical equivalent circuit. As can be seen from the figure, the output terminal (33) connected to the drive circuit (30) and the output monitor terminal (38) are connected to the drive circuit (30).
), a capacitor (40) is formed between it and the capacitor (40).

FIG. 3 is a timing chart when the present invention is applied when the drive circuit (30) does not output in phase. In the figure, 1 to n are output signals that actually appear at the output terminal (33), and M is the output waveform observed at the output monitor terminal (38). Since the rectangular wave of each output terminal (33) is directly applied to the output monitor terminal (38), it is possible to test all the output terminals (33) at once.

FIG. 4 is a timing chart when the present invention is applied in the case where the drive circuit (30) is a sample and hold circuit that performs simultaneous outputs. In this example, clock pulse C1
The rising edge of k indicates the mode in which each of the n sampling circuits takes in data, and only the kth sampling takes in unique input data, and only during the period T during which the control signal E is active, each of the n sampling circuits takes in data. Sampling data is output. In the same figure, \ is the output monitor terminal (38
), and the signal obtained at this time indicates the information of the second output terminal (33). child·
If input data is input in synchronization with each sampling, all output terminals (33) can be inspected.

In these embodiments, the probe section tU (37) has a simple shape and is therefore easy to process, and positioning is easy because only one probe section tU (37) is required regardless of the number of output terminals (33).

Furthermore, since a probe selection circuit is not required, the inspection device becomes inexpensive.

[Effects of the invention] This invention has a simple structure, reduces inspection costs, and
This is a test structure for a multi-output drive circuit board that reduces test time, and is extremely effective in testing circuits with a large number of output terminals.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an embodiment of the present invention, Fig. 2 is an equivalent circuit diagram of the embodiment shown in Fig. 1, and Fig. 3 is an application of the invention to a drive circuit that does not output in-phase. Figure 4 is a waveform diagram when this invention is applied to a sample hold circuit, Figure 5 is an FA98 diagram showing an example of a multi-output drive circuit board, and Figure 6 is a conventional multi-output drive circuit. FIG. 2 is a schematic diagram showing an example of a substrate inspection structure. (30)...Drive circuit (32)...Input terminal (33)...Output terminal (36)...Dielectric (37)...・・・Probe tube 4*2nd Fig. 1 Gol-+------- 2-bit →--1--1- K □J-□ ,, ,J"""LM 11 pieces ++-low-low Fig. 3 Fig. 4 Fig. 5 Fig. 6

Claims (1)

[Claims] In a test structure for a multi-output drive circuit board that includes an input terminal, a plurality of output terminals, and a drive circuit, the drive circuit may be a multi-output drive circuit that does not output in-phase, or a sample-hold drive circuit that simultaneously outputs multiple outputs. The output terminal is electrically connected to one probe electrode through a dielectric material, and the input signal of the sample hold drive circuit includes unique data for only one arbitrary sampling among the plurality of samplings. An inspection structure for a multi-output drive circuit board characterized by using drive conditions as follows.