JP2010197134A - Board inspecting jig - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out an electric inspection of a board to be inspected without increasing its board inspecting jigs and inspection frequencies even when the number of channels of a scanner of a board electric inspection apparatus gets low. <P>SOLUTION: A board inspecting jig is used, which is composed of a probe pin for contacting with an inspection point of a wiring pattern of the board to be inspected by the board electric inspection apparatus, and a connector having a terminal for electrically connecting with the probe pin, and which is characterized by including a choosing circuit for, in turn, choosing one among a plurality of probe pins and electrically connecting it to one terminal of the connector, thereby reducing the number of channels to be connected to the scanner of the board electric inspection apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a board inspection jig for an electric board inspection apparatus for electrically inspecting the continuity of a wiring pattern formed on a board to be inspected such as a printed wiring board.

  The continuity inspection of a printed wiring board (substrate to be inspected) having a plurality of wiring patterns 2 is performed by applying a voltage or current to an inspection point such as an electrode pad provided at an end of the pattern to be inspected, thereby resistance of the pattern A value is measured, and a pass / fail judgment is performed for a certain threshold value. As an apparatus for performing such a continuity test, an apparatus is known in which a needle-like probe pin is simultaneously brought into contact with a plurality of inspection points of a substrate to be inspected and a voltage or a current is applied thereto as in Patent Document 1. Yes.

  FIG. 1 is a schematic cross-sectional view showing an example of a wiring pattern 2 of a substrate 1 to be inspected by this board electrical inspection apparatus. The wiring pattern 2 has six upper inspection points 101 to 106 on the upper surface of the substrate 1 to be inspected and four lower inspection points 201 to 204 on the lower surface. In the inspected substrate 1 in FIG. 1, there are four circuit networks (nets) of the wiring pattern 2 to be inspected. The circuit network (net) is a group of wiring patterns 2 that are electrically connected and have the same potential. In the case of the inspected substrate 1 in FIG. 1, the combination of inspection points for conducting a continuity test between two points is between 201-101, 202-102, 202-103, 203-104, 203-105, There are 6 ways between 204-106. This continuity test between inspection points is a continuity check for checking continuity between inspection points and an insulation check for checking that the inspection points are insulated.

  FIG. 2 is a schematic diagram of a board electrical inspection apparatus for inspecting the board 1 to be inspected in FIG. Upper jig probe pins 301 to 306 to be brought into contact with the respective upper inspection points 101 to 106 of the substrate 1 to be inspected are assigned, and lower jig probe pins 401 to 404 to be brought into contact with the respective lower inspection points 201 to 204 are assigned. The tip of each probe pin is supported by the support 3 so as to accurately contact each inspection point. The other end of each probe pin is electrically connected to the signal cable, and is connected to the scanner 6 via the connector 5 attached to the support plate 4 of the board inspection jig, and signals to be inspected are sequentially selected. A current is applied to the selected signal by the DC current source 7, and the resistance value is calculated by measuring the voltage with the voltmeter 8. A structure in which the probe pin, the support 3, the support plate 4, and the connector 5 are integrated is a substrate inspection jig.

JP 2008-281406 A

In recent years, the density of printed wiring boards has been increasing, and the number of inspection points for printed wiring boards (board 1 to be inspected) has increased accordingly. On the other hand, since the number and position of the inspection points are different for each substrate 1 to be inspected, the substrate inspection jig is produced exclusively for each substrate 1 to be inspected. The board inspection jig is manufactured by increasing the number of probe pins by the number of inspection points when the number of inspection points of the inspected substrate 1 increases. On the other hand, since the scanner 6 of the board electrical inspection apparatus uses the scanner 6 with a fixed number of channels, the number of channels may be insufficient. In such cases, the following method was used. (A) A method for coping with by preparing a plurality of substrate inspection jigs and executing the inspection a plurality of times. This method has a drawback that it leads to an increase in man-hours and cost. (
b) A method of coping with the addition of the scanner 6. In this method, the scanner 6 is a very expensive part, which also has a drawback of increasing the cost. In the method described in Patent Document 1, although the inspection time can be shortened, when the number of channels of the scanner 6 is insufficient, a plurality of substrate inspection jigs must be prepared and inspected a plurality of times. There is a drawback that the cost increases.

  SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to perform an electrical inspection of a substrate 1 to be inspected without increasing the number of substrate inspection jigs and increasing the number of inspections even when the number of channels of the scanner 6 of the substrate electrical inspection apparatus is insufficient. And

  In order to solve the above-mentioned problems, the present invention is composed of a probe pin that is brought into contact with an inspection point of a wiring pattern of a substrate to be inspected by a substrate electrical inspection apparatus and a connector having a terminal that is electrically connected to the probe pin A board inspection jig comprising a selection circuit that sequentially selects one of the plurality of probe pins and electrically connects to one terminal of the connector.

  According to another aspect of the present invention, there is provided the substrate inspection jig, wherein the selection circuit is formed of a semiconductor integrated circuit.

  Further, the present invention is the above board inspection jig, wherein the probe pin connected to the selection circuit is disposed so as to contact one inspection point of a net having a plurality of inspection points, and the selection circuit is arranged. The board inspection jig is characterized in that at least one of the probe pins connected to the terminal of the connector without being interposed is arranged so as to contact another inspection point of the net.

  According to the present invention, even when the number of inspection points of the inspected substrate 1 exceeds the number of channels of the scanner 6 of the substrate electrical inspection apparatus, it is possible to suppress an increase in the substrate inspection jig and the number of inspections. In addition, an increase in cost associated with the addition of the scanner 6 can be suppressed.

It is a schematic diagram of the cross section of a to-be-inspected board | substrate. It is a schematic diagram of a substrate inspection jig and a substrate electrical inspection apparatus for inspecting a substrate to be inspected. It is a schematic diagram of the board | substrate inspection jig | tool of the Example of this invention. It is a circuit diagram of the selection circuit mounted in the board | substrate inspection jig | tool of the Example of this invention. It is a timing chart of operation | movement of the selection circuit of the Example of this invention.

  A mode for carrying out the present invention will be described with reference to FIGS. FIG. 3 shows the substrate inspection jig of this embodiment. In this embodiment, when there are 10 inspection points of the substrate 1 to be inspected with which the substrate inspection jig is brought into contact, the number of channels of the scanner 6 is only six channels, which is smaller than the number of inspection points. An embodiment of the present invention in the case where there is no case will be described.

  The substrate inspection jig of this embodiment has 10 probe pins 501 to 510 for inspecting 10 inspection points, and these are fixed by the support 3. The other end of the probe pin is connected to a signal cable, and the signal terminals of the probe pins 501 to 505 are electrically connected directly to the connector 5 and are electrically connected to the scanner 6 of the board electrical inspection apparatus at the time of inspection. On the other hand, the signal terminals of the probe pins 506 to 510 are connected to the input terminals F506 to F510 of the selection circuit 9.

  FIG. 4 shows an example of a circuit diagram of the selection circuit 9. The selection circuit 9 connects the output terminal of the D-FF (flip-flop) circuit 10 driven by the Clock signal to the input terminal of the AND circuit 11 and inverts the Reset signal to the other input terminal of the AND circuit 11. Connect the output terminal of the inverter circuit. Then, by connecting the output terminal of the AND circuit 11 to the D-FF circuit 10 in the next stage, a 5-bit counter circuit connected in five stages is configured. As shown in FIG. 5, when the Reset signal and the Clock signal are input to the selection circuit 9, the output signals from the output terminals Q1 to Q5 of the 5-bit counter circuit sequentially become H outputs.

  The output signals Q1 to Q5 of the 5-bit counter circuit of the selection circuit 9 are connected to the input terminals of the inverter circuits 14, and the output signals Q1 to Q5 of the counter circuit and the reverse phase signals of the output terminals of the inverter circuits 14 Are input to the switch control signal input terminal of the transfer gate 13. The input terminals F506 to F510 connected to the probe pins 506 to 510 are connected to the switch terminal of the transfer gate 13, and the output signals Q1 to Q5 of the counter circuit are supplied to the switch control signal input terminal at the timing of S506 to S510 in FIG. In addition, the switch terminals of the transfer gate 13 are sequentially brought into conduction with one output terminal T500 of the selection circuit 9. Then, the output terminal T500 is electrically connected to one terminal of the connector 5 of the board inspection jig. The connector 5 is provided with six terminals including five terminals connected to the signal terminals of the probe pins 501 to 505 and one terminal connected to the output terminal T500 of the transfer gate 13. Then, the six terminals of the connector 5 of the board inspection jig are connected to the input terminals of the scanner 6 of the board electrical inspection apparatus, and the continuity inspection is sequentially performed. In addition, the terminals of the connector 5 are further connected to the drive power supply terminal, the clock signal terminal, and the reset signal terminal of the selection circuit 9, and these terminals are also connected to the scanner 6 to switch the transfer gate 13. The scanner 6 is controlled.

  In the present invention, since only one inspection point connected to the selection circuit 9 is selected at the same time, the continuity inspection between the inspection points cannot be performed. In order to avoid the fact that the insulation check for checking the short-circuit failure between the nets to be insulated is not performed due to this problem, the probe pin electrically connected to the input terminals F506 to F510 of the selection circuit 9 is the inspection point where it contacts. Is preferably arranged so as to be limited to inspection points of a net including a plurality of inspection points. The reason for this is that if two nets with only one inspection point are connected to the selection circuit 9, the continuity test between the two nets cannot be performed. This is because it may not be perfect. Usually, the electrical inspection of the substrate 1 to be inspected is performed with an insulation check as well as a continuity check. The insulation check checks whether the inspection target net is insulated from all other nets. However, there is a problem that the insulation check is not performed between the inspection points connected to the selection circuit 9. This problem is limited to the inspection points of the net of the wiring pattern 2 having a plurality of inspection points such as the power supply or the ground, and the inspection points that contact the probe pins connected to the selection circuit 9 are out of the plurality of inspection points of the nets. The probe pin that contacts at least one point can be avoided by arranging the probe pin on the board inspection jig so as to be connected to the connector 5 without going through the selection circuit 9.

  Further, the selection circuit 9 in FIG. 4 is preferably a semiconductor electronic circuit, and is particularly preferably an LSI component in order to realize space saving. In that case, if the number of stages of the counter circuit in the LSI component is arbitrarily set and the required number of stages is used, the LSI component can be used as a general-purpose product, and the cost of the substrate inspection jig can be reduced.

  The present invention can be used for a substrate inspection jig for electrically inspecting conduction of a wiring pattern 2 formed on a substrate 1 to be inspected.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 2 ... Wiring pattern 3 ... Support body 4 ... Support plate 5 ... Connector 6 ... Scanner 7 ... DC current source 8 ... Voltmeter 9 ··· Selection circuit 10 ··· D-FF circuit 11 ··· AND circuit 12 and 14 · · · Inverter circuit 13 · · · Transfer gates 101 to 106 (upper side) inspection points 201 to 204 ( (Lower side) Inspection points 301 to 306 (Upper jig) Probe pins 401 to 404 (Lower jig) Probe pins 501 to 510 ... Probe pins F506, F507, F508, F509, F510 ..Input terminals Q1, Q2, Q3, Q4, Q5 of the selection circuit connected to the probe pins 506 to 510 .... Output signal T500 of the counter circuit .... Output terminals S506 to S510 of the selection circuit 9. The timing for conducting the signal et 510 to T500

Claims (3)

  A substrate inspection jig comprising a probe pin brought into contact with an inspection point of a wiring pattern of a substrate to be inspected by a substrate electrical inspection apparatus, and a connector having a terminal electrically connected to the probe pin, wherein the plurality of probe pins A board inspection jig comprising a selection circuit that sequentially selects one of the terminals and electrically connects to one terminal of the connector.   2. The substrate inspection jig according to claim 1, wherein the selection circuit is formed of a semiconductor integrated circuit.   The board inspection jig according to claim 1, wherein the probe pin connected to the selection circuit is disposed so as to contact one inspection point of a net having a plurality of inspection points, and does not pass through the selection circuit. The board inspection jig is characterized in that at least one of the probe pins connected to the terminal of the connector is placed in contact with another inspection point of the net.

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