JPH04355378A - Confirmation of contact probe - Google Patents

Abstract

PURPOSE:To confirm the positive contact of a probe with a desired terminal. CONSTITUTION:When it is confirmed that both terminals of an element to be measured are not short-circuited after the continuity between measuring. points 1(4), 2(5) and that between measuring points 3(6), 4(7) are confirmed by preceding inspection, a contact probe 1 is brought into contact with the measuring point 1 (4) and a contact probe 2 is brought into contact with the measuring point 2(5) and the contact state of the probe 1 is confirmed by a measuring part 9 and, continuously, the probe 1 held as it is and a contact probe 3 is brought into contact with the measuring point 3(6) and the probe 2 is brought into contact with the measuring point 4(7) to confirm the contact of the probe 3. By this operation, the contact of the probes 1, 3 with the measuring points 1(4), 3(6) can be confirmed and, by measuring both measuring points in this state by the measuring part 9, erroneous judgment such that both terminals of the element 8 a not short-circuited though they are short-circuited can be prevented.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention is a printed wiring board inspection method in which a plurality of contact probes are controlled by a position control device and applied to a desired portion of a printed circuit board to inspect the characteristics of elements on the printed circuit board. The present invention relates to a method for measuring a device (hereinafter referred to as a moving probe type board inspection device), and more specifically to a method for checking the contact state of a contact probe.

0002

2. Description of the Related Art Conventionally, in a probe movable board inspection apparatus, there has been no method for detecting whether a contact probe (hereinafter referred to as a probe) is accurately in contact with a printed circuit board (hereinafter referred to as a board).

0003

[Problems to be Solved by the Invention] In recent years, with the miniaturization of board-mounted components, short-circuit defects between component terminals are likely to occur, so a probe is used to inspect for short-circuits between measurement points. There are many cases. However, if the probe has poor contact, even if the terminals are short-circuited,
- Unable to detect faults and make incorrect judgments. The present invention has been made in order to prevent such misjudgments.

0004

[Means and Operations for Solving the Problems] The structure and operations of the present invention will be explained below with reference to FIG. Contact probes 1 (1), 2 (2), and 3 (3) are all movable probes attached to a position control device, and all measurement signals from each probe are input to a measurement section (9). In addition, continuity between measurement point 1 (4) and measurement point 2 (5) and measurement point 3 (6) and measurement point 4 (7) is also confirmed.
) has been confirmed in a previous inspection.

Now, let us consider the case of confirming that there is no short circuit between both terminals (measurement point 1 and measurement point 3) of the device under test (8). First, probe 1 (1) is brought into contact with measurement point 1 (4), probe 2 (2) is brought into contact with measurement point 2 (5), and continuity is confirmed by the measurement part (9). Then, leave probe 1 (1) as it is and touch probe 3 (3) to measurement point 3 (6) and probe 2 (2) to measurement point 4 (7) to ensure continuity. Check the contact of probe 3 (3).

Through the above operations, it has been confirmed that probe 1 (1) and probe 3 (3) are in contact with measurement point 1 (4) and measurement point 3 (6), respectively, and in this state, Measurement part (9) between both measurement points
By measuring with , it is possible to prevent an erroneous determination that there is no short circuit even though there is a short circuit.

[0007]

[Example] In the example of FIG. 1, measurement point 1, measurement point 2, measurement point 3, -3-measurement point 4,
shows a case in which connections are made by printed patterns, but it is equally possible to use cases in which connections are made by elements such as resistors and diodes. Further, although the description has been made assuming that the number of probes is three, the same method can be applied if there are three or more probes.

FIG. 2 shows another embodiment of the invention. Measurement point 1 (4), measurement point 2 (5)
, probe 1 (1) at measurement point 3 (6), respectively.
By bringing probe 2 (2) and probe 3 (3) into contact and detecting the protection diode of the integrated circuit (12),
Check the contact status of the probe. Thereafter, the presence or absence of a short circuit between measurement point 1 (4) and measurement point 3 (6) is inspected. In this case, contact confirmation can be performed without moving the probe.

[0009]

By using the method of the present invention, the contact state of a probe can be detected in a simple manner, and a short circuit confirmation test between measurement points can be reliably carried out.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a measurement method using the method of the present invention.

FIG. 2 is a diagram showing another measurement method using another method of the present invention.

[Explanation of symbols]

(1), (2), (3) are contact probes (4),
(5), (6), (7) are the measurement points (8) are the device under test (9) are the printed circuit board (10) are the printed circuit board (11) are the printed pattern (12) are the integrated circuit

Claims (1)

[Claims] 1. A printed circuit board inspection apparatus in which a plurality of contact probes are controlled by a position control device to sequentially conduct an electrical test on a desired part. A contact probe contact confirmation method characterized by confirmation by measuring a circuit part whose state has been determined.