JP2582181B2 - Continuity test equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to a continuity test apparatus, and more particularly to a continuity test apparatus for measuring a resistance by moving a probe to perform a continuity test on a wiring pattern of a printed board. A probe for contacting the object under test, a mechanism for moving the probe in a three-dimensional direction, and a control unit for controlling the mechanism. In the continuity test device having, a contact frequency check unit that checks the number of times the probe has contacted the test object, and a test point on the test object to which the probe contacts, according to an output signal from the contact frequency check unit. Is configured to be moved.

[Industrial applications]

The present invention relates to a continuity test apparatus, and more particularly to a continuity test apparatus that performs a resistance measurement by moving a probe to perform a continuity test on a pad of a printed board or the like.

[Conventional technology]

Conventionally, a probe that moves in a three-dimensional direction is brought into contact with a pad formed on a printed board to be tested, and a resistance value obtained by contacting the probe is sent to a measuring unit, and a predetermined resistance measurement is performed. , A conduction test of pads on the printed board was performed.

 FIG. 4 shows the processing flow.

<< Step 200 >> First, the amount of movement of the probe is calculated with the printed board set on the table.

<< Step 201 >> The calculated movement amount is sent to the control unit to set the movement amount.

<< Step 202 >> Based on the set movement amount, the mechanism is moved to bring the probe to an arbitrary position, that is, just above the pad on which the test is to be performed.

<< Step 203 >> When the test preparation is completed, the probe is lowered so that the probe comes into contact with the pad to be tested.

<< Step 204 >> After confirming that the probe and the pad are in contact with each other, measurement such as resistance measurement is actually performed.

<< Step 205 >> When the predetermined resistance measurement for an arbitrary pad is completed,
Raise the probe.

<< Step 206 >> It is determined whether or not all the portions to be tested have been completed for one printed board, and if it is necessary to continuously test a different test portion, the process returns to step 200. If it is not necessary to perform the test, the test for the printed board is terminated.

When the pad and the probe are brought into contact with each other and the resistance is measured as described above, the contact resistance between them becomes a problem.

For this reason, a method is used in which the tip of the probe is sharpened or the pressure applied to the pad of the probe is increased.

[Problems to be solved by the invention]

However, in the past, the probe always touched the same point on the pad.If the probe touched the same pad a number of times, the pad surface would be worn or deformed due to the shape of the tip of the probe and the pressing force, causing the contact resistance to become diversified. In some cases, the conductivity test was adversely affected.

Accordingly, an object of the present invention is to permanently reduce the contact resistance between the probe and the test object.

[Means for solving the problem]

An object of the present invention is to provide a continuity test device comprising: a probe 1 that comes into contact with an object to be tested; a mechanism unit 2 that moves the probe 1 in a three-dimensional direction; and a control unit 3 that controls the mechanism unit 2. A contact frequency check unit 6 for checking the number of times the probe 1 has contacted the test object; and a test point on the test object to which the probe 1 contacts according to an output signal from the contact frequency check unit 6. Can be achieved by a continuity test apparatus characterized in that

[Action]

That is, the number of contacts between the probe and the object under test is counted, and when the number of contacts exceeds a predetermined number of contacts, the test point on the object under test is shifted to perform the test. It is possible to permanently reduce the contact resistance with the object.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 3.

FIG. 1 is a view showing an embodiment of the present invention, FIG. 2 is a view showing a relationship between a contact position of a probe and a pad, and FIG. 3 is a view showing a processing flow of the present invention.

In this embodiment, the resistance measurement test of the continuity test is used as the test content.

In FIGS. 1 and 2, reference numeral 1 denotes a probe for measuring the resistance of an object to be tested, which will be described later, and which comes into contact with the object to be tested.

Reference numeral 2 denotes a mechanism for driving the probe to move to the object under test. The mechanism 2 is capable of moving the probe 1 in three-dimensional directions, that is, in the X, Y, and Z directions. Has become.

Reference numeral 3 denotes a control unit that sets the amount of movement of the mechanism unit 2 that moves the probe 1 and controls the entire continuity test device.

Reference numeral 4 denotes a measuring unit for bringing the probe 1 into contact with an object to be tested, that is, a pad 8 on the printed board 5, and measuring the contact resistance.

Reference numeral 5 denotes a printed board, on the surface of which is formed a pad 8 which is in contact with the probe 1 and whose resistance is measured.

Reference numeral 6 denotes a contact frequency check unit which counts the number of times the probe 1 has contacted the same pad. The maximum contact frequency, which is a threshold value, is set in advance. 1 is compared with the number of times of contact, and if the number exceeds the maximum number of times of contact, a signal to that effect is output.

Reference numeral 7 denotes a moving amount setting unit, and the contact number checking unit 6
Thus, when a signal indicating that the number of times of contact exceeds the maximum number of contacts is output, a movement amount for moving a point contacted by the probe 1 on the same pad by a predetermined distance is set. This movement amount is notified to the control unit 4, and the control unit 4
Then, the mechanism unit 2 is driven based on this movement amount, and the point (contact point) where the probe 1 comes into contact is shifted even on the same pad.

8 is a pad, which is a contact destination of the probe 1;
This corresponds to the test object of the present invention.

Reference numeral 9 denotes a contact point (conventional), and conventionally, only the contact point was brought into contact with the probe 1.

Reference numerals 10 to 13 denote first to fourth contact points, which will be described later. In this example, the first contact point 10 is the contact point of the first probe 1 and the second, third, and fourth contact points The contact point of the probe 1 is changed on the same pad in accordance with the output of the contact number check unit 6 in the order of.

Next, the relationship between the contact positions of the probe and the pad will be described with reference to FIG.

In the figure, a and b represent X of the pad 8 to be tested.
Φd indicates the size of the pad 8
X indicates the pitch of the X-direction contact points on the same pad, and y indicates the pitch of the Y-direction contact points on the same pad.

The setting of the distances x and y is calculated by the following equation.

d + α ≦ x ≦ ad−α d + α ≦ y ≦ bd−α * α is the positioning accuracy of the mechanism. FIG. 3 shows the processing flow.

<< Step 100 >> First, the amount of movement of the probe 1 is calculated with the printed board 5 set on the table.

<< Step 101 >> It is checked how many times the probe 1 has contacted the same contact point with the pad 8 to be tested. At this time, if the preset maximum number of contacts exceeds this contact,
Move to step 102. If not exceeded, the process proceeds to step 103.

<< Step 102 >> If the maximum number of contacts has been exceeded in step 101, the movement amount setting section 7 moves the contact point from the first contact point 10 to the second contact point 11 shown in FIG. A correction value for the probe 1 is set based on the control. This contact point is the first contact point 10 → the second contact point 11 → the third contact point.
It goes around 12 → fourth contact point 13 → first contact point 10.

<< Step 103 >> The moving amount calculated by step 100 or AND of step 100 and step 101 is sent to the control unit 3 to set the moving amount.

<< Step 104 >> Based on the set amount of movement, the mechanical unit 2 is driven to bring the probe 1 to an arbitrary position, that is, directly above the pad 8 to be tested.

<< Step 105 >> When the test preparation is completed, the probe 1 is lowered so that the probe 1 comes into contact with the pad 8 to be tested.

<< Step 106 >> After confirming that the probe 1 is in contact with the pad 8, a test such as resistance measurement is actually performed.

<< Step 107 >> When the predetermined resistance measurement for an arbitrary pad 8 is completed, the probe 1 is raised.

<< Step 108 >> It is determined whether all the portions to be tested have been completed for one printed board 5, and if it is necessary to continue testing a different test portion, the process returns to step 100. If it is not necessary to perform the test, the test for the printed board is terminated.

In the present invention, if the size of the pad 8 is sufficiently large with respect to the outer diameter φ of the tip of the probe 1, it is more effective to increase the number of contact points.

Furthermore, the contact point once contacted by the probe 1 is not used as a contact point thereafter. That is, if the contact point is changed each time the probe 1 contacts the pad 8, the resistance measurement must always be performed under the same conditions. Can be.

〔The invention's effect〕

As described above, according to the present invention, the contact point of the probe is changed to such an extent that the contact point does not adversely affect the continuity test. It greatly contributes to the improvement of the performance of electronic devices that require the following.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of the present invention, FIG. 2 is a view showing a relationship between a contact position of a probe and a pad, FIG. 3 is a view showing a processing flow of the present invention, FIG. FIG. 1 is a diagram showing a conventional processing flow. In the figure, 1 ... probe, 2 ... mechanical section, 3 ... control section, 4 ... measuring section, 5 ... printed board, 6 ... contact frequency check section, 7 ... movement amount setting section, 8 ... … Indicates a pad and.

Claims (1)

(57) [Claims] 1. A probe (1) contacting an object under test (8), a mechanism (2) for moving the probe (1) in a three-dimensional direction, and control of the mechanism (2). A control unit (3), comprising: a contact frequency check unit (6) for checking the number of times the probe (1) has contacted the test object (8); and a contact frequency check unit (6). A continuity test apparatus characterized by moving a contact point on the object under test (8) with which the probe (1) is in contact with an output signal from 6).