JP4068248B2 - Insulation inspection apparatus for substrate and insulation inspection method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an insulation inspection device for a substrate and an insulation inspection method thereof for inspecting the quality of an insulation state between wiring patterns formed on a printed circuit board or the like.
[0002]
[Prior art]
In general, when a wiring pattern is formed on a printed circuit board, the wiring pattern is normally formed by conducting a continuity test or insulation test using a board inspection device before mounting electronic components. A check is made to see if it was done.
[0003]
FIG. 9 is a diagram illustrating an example of a printed circuit board to be inspected. In the figure, numbers 1 to 18 are inspection point numbers input to the substrate inspection apparatus. In general, a point marked with an inspection point number is referred to as a “net pin”, and a set of a plurality of net pins that are electrically connected to each other is referred to as a “inspection net”. Called. Accordingly, in the printed circuit board 20 of FIG. 9, assuming that the number of inspection nets is N, the number of single pins is S, and the number of wiring patterns insulated from each other is M, N = 6, S = 4, M = N + S = It is 10. Hereinafter, the continuity test and the insulation test for the printed circuit board 20 of FIG. 9 will be described in order.
[0004]
FIG. 10 is a diagram showing an inspection net list of the printed circuit board 20 of FIG. 9 and net pins to be subjected to continuity inspection. In the continuity inspection, since it is necessary to inspect the continuity state between the net pins in the same inspection net, the inspection is completed with a total of eight connection states as shown in FIG. Since inspection point numbers 15 to 18 are single pins, there is no need to perform a continuity inspection.
[0005]
On the other hand, in the insulation inspection, a head pin representing an inspection net is set, and the insulation inspection is performed according to the insulation state between the head pins. That is, a head pin representing each inspection net is connected to a pair of electrodes, and when an electric signal is applied to one electrode, the insulation state between the head pins connected to each electrode is determined by the level of the electric signal of the other electrode. Determined.
For example, a net pin having the smallest inspection point number in each inspection net is used as a head pin. The single pin itself becomes a head pin. Accordingly, the printed circuit board 20 of FIG. 9 has a total of ten head pins P1 to P10 as shown in the figure.
[0006]
FIG. 11 is a diagram for explaining the procedure of a conventional insulation test. In the figure, the electrode connected to each head pin is, for example, a “●” mark as a positive electrode and a “◯” mark as a negative electrode. In the conventional insulation inspection, as shown in FIG. 11, the connection state to the pair of electrodes is performed by one pin to many pins. That is, the first time, the head pin P1 is connected to the positive electrode, the head pins P2 to P10 are connected to the negative electrode, and the inspection is performed. The second time, the head pin P2 is connected to the positive electrode, and the head pins P3 to P10 are connected to the negative electrode. And was inspecting.
[0007]
[Problems to be solved by the invention]
As described above, in the conventional insulation inspection, since the connection state to the pair of electrodes is performed by one pin to many pins, when the number of wiring patterns is M, the number of inspections C is:
[0008]
[Expression 1]
C = M-1
become. That is, C = 9 in the printed circuit board of FIG. In the above description, the number M of wiring patterns is limited to “10” in order to help understanding. However, in a general printed circuit board, since M = 500 to 2000, C = 499 to 1999. Therefore, a very large number of inspections are required, and the insulation inspection takes a long time.
[0009]
The present invention solves the above-described problem, and provides a substrate insulation inspection device and an insulation inspection method thereof that can shorten the insulation inspection time by reducing the number of times of connection state switching for performing an insulation inspection. With the goal.
[0010]
[Means for Solving the Problems]
According to the first aspect of the present invention, in a substrate on which M (M is an integer of 5 or more) wiring patterns are formed, representatives from No. 1 to No. M respectively set at predetermined positions on the respective wiring patterns are provided. A substrate insulation inspection apparatus for inspecting an insulation state between the wiring patterns by inspecting an insulation state between pins, and electrically connected to the first to Mth representative pins, respectively. Possible first electrode and second electrode, switching control means for controlling switching of connection state between the first and second electrodes and the representative pins, one of the first electrode and the second electrode Based on the level of the electrical signal of the other electrode when a predetermined electrical signal is applied to the electrode, whether the insulation state between the representative pins connected to each of the electrodes is good or bad for each switching of the connection state Insulation determination means for determining As a first connection state, the control means connects the first and second representative pins to the first electrode, and connects the third to Mth representative pins to the second electrode. As the second connection state, the second to fourth representative pins are connected to the first electrode, and the first and fifth to Mth representative pins are connected to the second electrode. As the connection state after the second time, two representative pins connected to the first electrode from the second connection state are slid toward the Mth side, respectively, and the representative pin connected to the slid first electrode One representative pin adjacent to the first side with respect to the pin and all representative pins on the Mth side are connected to the second electrode, and the number of representative pins connected to the first electrode is less than three. It is characterized by the fact that the switching ends with the connected state becoming .
[0011]
According to this configuration, the first to Mth representative pins respectively set at predetermined positions on M (M is an integer of 5 or more) wiring patterns formed on the substrate, and each representative pin The switching of the connection state between the electrically connectable first electrode and the second electrode is controlled, and the other electrode when a predetermined electrical signal is applied to one of the first electrode and the second electrode is controlled. Based on the level of the electrical signal, whether the insulation state between the representative pins connected to each electrode is good or bad is determined every time the connection state is switched.
[0012]
Here, as the first connection state, the first and second representative pins are connected to the first electrode, and the third to Mth representative pins are connected to the second electrode. As the second connection state, the second to fourth representative pins are connected to the first electrode, and the first and fifth to Mth representative pins are connected to the second electrode. The In addition, as the connection state after the third time, two representative pins connected to the first electrode from the second connection state are slid toward the Mth side and connected to the slid first electrode. One representative pin adjacent to the first side and all the representative pins on the Mth side are connected to the second electrode. Then, the switching is completed when the number of representative pins connected to the first electrode is less than three.
[0013]
As a result, the number of switching of the connection state for determining the insulation state between all the representative pins is reduced, and the insulation inspection time is shortened.
[0014]
According to a second aspect of the present invention, in a substrate on which M (M is an integer of 6 or more) wiring patterns are formed, from No. 1 to No. M respectively set at predetermined positions on the wiring patterns. A substrate insulation inspection apparatus for inspecting an insulation state between the wiring patterns by inspecting an insulation state between the representative pins of the first to Mth representative pins. The first and second electrodes connectable to each other, the switching control means for controlling the switching of the connection state between the first and second electrodes and the representative pins, and when a predetermined electrical signal is applied to one of the electrodes Insulation determination means for determining whether the insulation state between the representative pins connected to each of the electrodes is good or bad based on the level of the electrical signal of the other electrode of each of the connection states, and The switching control means determines the initial connection state and The first representative pin is connected to the first electrode, and the second and third representative pins or all the second to Mth representative pins are connected to the second electrode. As the second connection state, when only the second and third representative pins are connected to the second electrode in the first connection state, the first to third representative pins are connected in the first connection state. When all the 2nd to Mth representative pins are connected to the second electrode, the 2nd and 3rd representative pins are connected to the first electrode, respectively, and the 4th to Mth The third representative pin is connected to the second electrode, and as the third connection state, the third to fifth representative pins are connected to the first electrode, and the second and sixth to Mth pins are connected. No. representative pin is connected to the second electrode, and the fourth and subsequent connection states are connected to the first electrode from the third connection state. Two representative pins are slid toward the Mth side, and one representative pin and the Mth adjacent to the first side with respect to the representative pin connected to the slid first electrode All the representative pins on the number side are connected to the second electrode, and the switching is completed in a connection state in which the number of representative pins connected to the first electrode is less than three.
[0015]
According to this configuration, the first to Mth representative pins set at predetermined positions on M (M is an integer of 6 or more) wiring patterns formed on the substrate, and the representative pins respectively The switching of the connection state between the electrically connectable first electrode and the second electrode is controlled, and the other electrode when a predetermined electrical signal is applied to one of the first electrode and the second electrode is controlled. Based on the level of the electrical signal, whether the insulation state between the representative pins connected to each electrode is good or bad is determined every time the connection state is switched.
[0016]
Here, for example, as the first connection state, when the first representative pin is connected to the first electrode and the second and third representative pins are connected to the second electrode, the second time As the connection state, the first to third representative pins are connected to the first electrode, and the fourth to Mth representative pins are connected to the second electrode.
[0017]
On the other hand, for example, as the first connection state, when the first representative pin is connected to the first electrode and all the second to Mth representative pins are connected to the second electrode, 2 As the second connection state, the second and third representative pins are connected to the first electrode, and the fourth to Mth representative pins are connected to the second electrode.
[0018]
As the third connection state, the third to fifth representative pins are connected to the first electrode, and the second and sixth to Mth representative pins are connected to the second electrode. The Also, as the connection state after the fourth time, two representative pins connected to the first electrode from the third connection state are slid toward the Mth side and connected to the slid first electrode. One representative pin adjacent to the first side and all the representative pins on the Mth side are connected to the second electrode. Then, the switching is completed when the number of representative pins connected to the first electrode is less than three.
[0019]
As a result, the number of switching of the connection state for determining the insulation state between all the representative pins is reduced, and the insulation inspection time is shortened.
[0020]
According to a third aspect of the present invention, in a substrate on which M (M is an integer of 5 or more) wiring patterns are formed, from No. 1 to No. M respectively set at predetermined positions on the wiring patterns. A substrate insulation inspection method for inspecting an insulation state between each of the wiring patterns by inspecting an insulation state between the representative pins of each of the first to Mth representative pins. The other electrode when a predetermined electrical signal is applied to one of the first electrode and the second electrode with the first and second electrodes connectable to each representative pin and the representative pin connected to each other The following steps (1) and (2) are executed in this order in order to determine whether the insulation state between the representative pins connected to each of the electrodes is good or bad based on the level of the electrical signal. After that, the number of representative pins connected to the first electrode is The following step (3) is repeated until the number is less than three.
[0021]
(1) connecting the first and second representative pins to the first electrode and performing the determination in a state where the third to Mth representative pins are connected to the second electrode;
(2) The second to fourth representative pins are connected to the first electrode, and the above determination is made with the first and fifth to Mth representative pins connected to the second electrode. Process to perform,
(3) Two representative pins connected to the first electrode are slid toward the Mth side, and adjacent to the first side with respect to the slid representative pins connected to the first electrode. Performing the determination in a state in which one representative pin and all the M-th representative pins are connected to the second electrode.
[0022]
According to this method, the first to Mth representative pins respectively set at predetermined positions on M (M is an integer of 5 or more) wiring patterns formed on the substrate, and the representative pins respectively. The electrical signal of the other electrode when a predetermined electrical signal is applied to one of the first electrode and the second electrode in a state where the electrically connectable first electrode and the second electrode are connected Based on the level, it is determined whether the insulation state between the representative pins connected to each electrode is good or bad.
[0023]
At this time, the first and second representative pins are connected to the first electrode, and the determination is performed in a state where the third to Mth representative pins are connected to the second electrode (1) and A step (2) of connecting the second to fourth representative pins to the first electrode and making the determination in a state where the first and fifth to Mth representative pins are connected to the second electrode. Are executed in this order, and two representative pins connected to the first electrode are slid toward the Mth side, and the first representative pin connected to the slid first electrode is The step (3) in which the above determination is performed in a state where one representative pin adjacent to the number side and all the representative pins on the Mth side are connected to the second electrode, the number of representative pins connected to the first electrode is Repeat until less than three.
[0024]
As a result, the number of switching of the connection state for determining the insulation state between all the representative pins is reduced, and the insulation inspection time is shortened.
[0025]
According to a fourth aspect of the present invention, in a substrate on which M (M is an integer of 6 or more) wiring patterns are formed, from No. 1 to No. M respectively set at predetermined positions on the wiring patterns. A substrate insulation inspection method for inspecting an insulation state between each of the wiring patterns by inspecting an insulation state between the representative pins of each of the first to Mth representative pins. The other electrode when a predetermined electrical signal is applied to one of the first electrode and the second electrode with the first and second electrodes connectable to each representative pin and the representative pin connected to each other The following steps (1), (2) and (3) are performed to determine whether the insulation state between the representative pins connected to each electrode is good or bad based on the level of the electrical signal. After executing in this order, the representative pins connected to the first electrode The number is characterized in that to repeat the following steps (4) to below three.
[0026]
(1) The first representative pin is connected to the first electrode, and the second and third representative pins or all the second to Mth representative pins are connected to the second electrode. Performing the above determination in a state,
(2) When only the second and third representative pins are connected to the second electrode in the step (1), the first to third representative pins are connected to the second pin in the step (1). When all the representative pins of No. M to No. M are connected to the second electrode, the No. 2 and No. 3 representative pins are respectively connected to the first electrode, and the No. 4 to No. M pins are connected. Performing the determination in a state where the representative pin is connected to the second electrode;
(3) The third to fifth representative pins are connected to the first electrode, and the second and sixth to Mth representative pins are connected to the second electrode. Process to perform,
(4) Two representative pins connected to the first electrode are slid toward the Mth side and adjacent to the first side with respect to the slid representative pins connected to the first electrode. Performing the determination in a state in which one representative pin and all the M-th representative pins are connected to the second electrode.
[0027]
According to this method, the first to Mth representative pins respectively set at predetermined positions on the M (M is an integer of 6 or more) wiring patterns formed on the substrate, and the representative pins respectively. The electrical signal of the other electrode when a predetermined electrical signal is applied to one of the first electrode and the second electrode in a state where the electrically connectable first electrode and the second electrode are connected Based on the level, it is determined whether the insulation state between the representative pins connected to each electrode is good or bad.
[0028]
At this time, the first representative pin is connected to the first electrode, and the second and third representative pins or all the second to Mth representative pins are connected to the second electrode. Step (1) for performing the above determination, and when only the second and third representative pins are connected to the second electrode in this step (1), the first to third representative pins are connected to the step (1 ), When all the 2nd to Mth representative pins are connected to the second electrode, the 2nd and 3rd representative pins are connected to the first electrode, respectively, and the 4th to Mth (2) performing the above determination in a state where the representative pin of the number is connected to the second electrode, and connecting the third to fifth representative pins to the first electrode, and the second and sixth to After the step (3) in which the above determination is performed in a state in which the Mth representative pin is connected to the second electrode, the representative pins connected to the first electrode are respectively performed. And slide two by two toward the Mth side, and one representative pin adjacent to the first side with respect to the representative pin connected to the slid first electrode and all of the Mth side The step (4) of performing the above determination with the representative pin connected to the second electrode is repeated until the number of representative pins connected to the first electrode is less than three.
[0029]
As a result, the number of switching of the connection state for determining the insulation state between all the representative pins is reduced, and the insulation inspection time is shortened.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram showing an electrical configuration of an embodiment of a substrate insulation inspection apparatus according to the present invention.
This substrate insulation inspection apparatus 30 includes a positive electrode 41, a negative electrode 42, a connection portion 50, and a control means 60, and inspects the quality of the insulation state between the wiring patterns on the printed circuit board 20 to be inspected. It is.
[0031]
In the present embodiment, the printed circuit board 20 to be inspected is assumed to be shown in FIG. That is, the net pins having inspection point numbers 1 to 18 and having the smallest inspection point number in each inspection net are used as head pins. The net pin is set at a predetermined position on the wiring pattern, for example, an end.
[0032]
That is, the net pin 1 of the inspection net 1-2-4 is the head pin P1, the net pin 3 of the inspection net 3-6 is the head pin P2, and the net pin 5 of the inspection net 5-9-10 is the head pin P3. The net pin 7 of 7-8 is a head pin P4, the net pin 11 of the inspection net 11-12 is a head pin P5, and the net pin 13 of the inspection net 13-14 is a head pin P6.
[0033]
The single pins themselves become head pins, and the single pins 15, 16, 17, and 18 are head pins P7, P8, P9, and P10, respectively.
[0034]
Thus, the head pin constitutes a representative pin representing each inspection net and a single pin. Therefore, if the number of inspection nets is N, the number of single pins is S, and the number of wiring patterns insulated from each other is M, the number of head pins is M, which is equal to the number of wiring patterns. As described above, in the printed circuit board 20 of FIG. 9, N = 6, S = 4, and M = N + S = 10.
[0035]
Returning to FIG. 1, the connection unit 50 includes probes B <b> 1 to B <b> 10 and a switch unit 51 made of a transistor or the like. The probes B1 to B10 are configured to be able to contact the head pins P1 to P10 of the printed circuit board 20, respectively. The switch unit 51 is formed of a transistor or the like, and turns on / off the connection between the probes B1 to B10 and the positive electrode 41 or the negative electrode 42, respectively.
[0036]
When the switch unit 51 is switched by the connection unit 50 while the probes B1 to B10 are in contact with the head pins P1 to P10, the connection state between the head pins P1 to P10 and the positive electrode 41 or the negative electrode 42 is switched.
[0037]
The probes B1 to B10 may not be in direct contact with the head pins P1 to P10, and may be configured to be electrically connected to the head pins P1 to P10, for example, electrostatically coupled. That's fine.
[0038]
The control means 60 is composed of a CPU, an electronic circuit, and the like, and includes a switching control means 61, an insulation determination means 62, and a failure analysis control means 63 as functional blocks. The switching control means 61 has a function of switching the connection state of the switch unit 51, and the switching procedure will be described later.
[0039]
The insulation determination unit 62 includes a signal application unit 71, a signal detection unit 72, and a level determination unit 73 as functional blocks. The signal applying means 71 applies an electric signal of a predetermined level to the head pin connected to the positive electrode 41 via the connecting portion 51. The signal detecting means 72 is connected to the negative electrode 42 via the connecting portion 51 when the electric signal is applied. The level of the electric signal of the head pin connected to is detected.
[0040]
The level determination means 73 compares the level of the electrical signal detected by the signal detection means 72 with a preset level, and insulates between the head pin connected to the positive electrode 41 and the head pin connected to the negative electrode 42. The state is determined.
[0041]
In the present embodiment, for example, the signal applying unit 71 applies a predetermined level voltage as an electric signal, and the signal detecting unit 72 detects a current level as an electric signal. Then, the level determination means 73 obtains a resistance value from the voltage level and the current level, and when the resistance value is equal to or higher than a predetermined level, the insulation state is good, and when the resistance value is lower than the predetermined level, the insulation state is bad. judge.
[0042]
The defect analysis control means 63 performs a defect analysis process for specifying a defective portion when a defect is detected in the insulation inspection, and the contents thereof will be described later.
[0043]
The head pins P1 to P10 constitute a representative pin, the positive electrode 41 constitutes one of the first electrode and the second electrode, and the negative electrode 42 constitutes the other electrode.
[0044]
Next, switching of the connection state between the head pins P1 to P10 and the positive electrode 41 and the negative electrode 42 by the switching control means 61 will be described along the flowchart of FIG. 2 with reference to FIG. FIG. 2 is a flowchart showing a connection state switching procedure. FIG. 3 is a diagram for explaining the switching of the connection state of the electrodes connected to each head pin. The “●” mark corresponding to each head pin indicates the state connected to the positive electrode 41, and the “◯” mark indicates the state connected to the negative electrode 42. Is shown.
[0045]
In FIG. 2, first and second head pins P1 and P2 are connected to the positive electrode 41, and the third to Mth (M is an integer of 5 or more. In this embodiment, for example, M = 10. ) No. head pins P3 to P10 are connected to the negative electrode 42 (step # 100), and the insulation state is determined (step # 110). That is, the first inspection in FIG. 3 is performed.
[0046]
If not defective (NO in step # 110), the second to fourth head pins P2 to P4 are connected to the positive electrode 41, and the first and fifth to Mth head pins. With P1, P5 to P10 connected to the negative electrode 42 (step # 120), the insulation state is determined (step # 130). That is, the second inspection in FIG. 3 is performed.
[0047]
If not defective (NO in step # 130), then, two head pins connected to the positive electrode 41 are slid as they are toward the M-th (step # 140), and then the positive electrode is moved by this slide. It is determined whether or not there are three head pins connected to the terminal 41 (step # 150), and if there are three (YES in step # 150), it is determined whether or not the head pin remains on the Mth side. (Step # 160).
[0048]
In FIG. 3, for example, when moving from the second inspection to the third inspection, if two head pins connected to the positive electrode 41 are slid as they are toward the Mth, they are connected to the positive electrode 41. The head pins are switched from the head pins P2 to P4 to the head pins P4 to P6. As a result, the number of head pins connected to the positive electrode 41 remains three, and the head pins P7 to P10 remain on the Mth side. The same applies when moving from the third inspection to the fourth inspection.
[0049]
Returning to FIG. 2, if the head pin remains on the M-th side (YES in step # 160), one head pin and three on the first side adjacent to the three head pins connected to the positive electrode 41 All the head pins on the Mth side of the head pins are connected to the negative electrode 42 (step # 170). That is, the third and fourth connection states in FIG.
[0050]
On the other hand, if there is no head pin remaining on the M-th side of the three head pins connected to the positive electrode 41 (NO in step # 160), one head pin on the first side adjacent to the three head pins is a negative electrode. 42 (step # 180). That is, the fifth connection state in FIG.
[0051]
Next, an insulation state is determined in this connected state (step # 190), and if not defective (NO in step # 190), the process returns to step # 140 and the above procedure is repeated.
[0052]
On the other hand, if there are not three head pins connected to the positive electrode 41 in step # 150 (NO in step # 150), one adjacent first head pin is connected to the negative electrode 42 (step # 200). ). That is, the sixth connection state in FIG.
[0053]
In this state, the insulation state is determined (step # 210), and if not defective (NO in step # 210), the process ends.
[0054]
If it is determined in steps # 110, # 130, # 190, and # 210 that the insulation state is defective (NO in steps # 110, # 130, # 190, and # 210), a failure analysis process described later (step After executing # 220, # 230, # 240, # 250), the process proceeds to the next step, that is, the next step when YES in steps # 110, # 130, # 190, # 210.
[0055]
Next, with reference to FIG. 3, a description will be given of the fact that the insulation inspection of all combinations of head pins can be performed by switching the connection state.
In the first inspection, an inspection of the insulation state between the head pins P1 and P2 and the head pins P3 to P10 is performed. Note that the insulation state between the head pin P1 and the head pin P2 remains unknown.
[0056]
In the second inspection, an inspection of the insulation state between the head pins P2 to P4 and the head pins P1, P5 to P10 is performed. Therefore, if this inspection result is good, it is confirmed that the insulation state between the head pin P1 and the head pin P2 is good, and the insulation inspection of the head pins P1 and P2 is completed. The insulation state between the head pin P3 and the head pin P4 remains unclear.
[0057]
In the third inspection, an inspection of the insulation state between the head pins P4 to P6 and the head pins P3 and P7 to P10 is performed. Therefore, if this inspection result is good, it is confirmed that the insulation state between the head pin P3 and the head pin P4 is good, and the insulation inspection of the head pins P3 and P4 is completed. The insulation state between the head pin P5 and the head pin P6 remains unclear.
[0058]
Similarly, in the fourth inspection, if the inspection result is good, it is confirmed that the insulation state between the head pin P5 and the head pin P6 is good, and the insulation inspection of the head pins P5 and P6 is performed. It will be completed. In the fifth inspection, if the inspection result is good, it is confirmed that the insulation state between the head pin P7 and the head pin P8 is good, and the insulation inspection of the head pins P7 and P8 is completed. It becomes.
[0059]
And if the inspection result is good in the sixth inspection, it is confirmed that the insulation state between the head pin P9 and the head pin P10, which was unknown in the fifth inspection, is good. The insulation inspection of the head pins P9 and P10 is completed.
[0060]
In this way, there are three adjacent head pins connected to the positive electrode 41, and two of them are slid toward the Mth side, and one headpin adjacent to the first side is connected to the negative electrode 42. As a result, the insulation state of the head pin, which was unknown in the previous inspection, can be confirmed.
[0061]
As a result, in the second to sixth inspections, the insulation inspection of the head pins is completed two by two, and the insulation inspection is completed in a total of six inspections, which is significantly larger than the conventional number of inspections of nine. The number of inspections can be reduced.
[0062]
Here, in the present embodiment, the number of inspections C when the number of head pins is M will be described.
[0063]
As described above, in the second to final inspections, two pieces are completed, so when the number M of head pins is an even number, the number of inspections C is:
[0064]
[Expression 2]
C = M / 2 + 1
It becomes. The second term on the right side of Equation 2 corresponds to the first inspection.
[0065]
On the other hand, when the number M of the head pins is an odd number, the insulation test of the M-th head pin is unknown in the number of times the insulation test of the (M-2) -th and (M-1) -th head pins is completed. Since the target head pin does not exist, the final number of times the insulation inspection of the (M-2) th and (M-1) th headpins is completed. Therefore, when the number M of head pins is an odd number, the number is equal to the number of inspections when the number of head pins is (M−1). Therefore, the number of inspections C is
[0066]
[Equation 3]
C = (M−1) / 2 + 1
It becomes.
[0067]
As described above, since M = 500 to 2000, normally, according to the present embodiment, C = 251 to 1001, and the number of inspections is greatly reduced to about a half of the conventional number 1 described above. be able to.
[0068]
Further, in the continuity test and the insulation test, since the inspection time for the insulation test usually requires about 2 to 3 times the inspection time for the continuity test, realization of the high speed of the insulation test contributes to the high speed of the inspection apparatus. Therefore, it is possible to reduce the cost required for substrate inspection, thereby reducing the production cost of the substrate.
[0069]
Next, the failure analysis processing by the failure analysis control means 63 will be described.
As described with reference to FIGS. 1 and 2, when a failure is detected in the insulation inspection, the failure analysis processing is performed after the failure analysis processing is performed, and then the insulation inspection is restored.
[0070]
That is, in the conventional insulation test, for example, when the first test in FIG. 11 is defective, the head pins connected to the negative electrode 42 are divided into a group consisting of head pins P2 to P5 and a group consisting of head pins P6 to P10, for example. A group including a head pin that is divided and has poor insulation with respect to the head pin P1 is identified, and then the group is further divided into small groups, and finally insulation failure with the head pin P1. A failure analysis process for identifying the head pin is executed. When the failure analysis process is completed, the process returns to the insulation inspection, and the second and subsequent insulation inspections are executed.
[0071]
On the other hand, in the present embodiment, for example, when the first inspection in FIG. 3 is defective, before the head pins P3 to P10 connected to the negative electrode 42 are divided into groups, Therefore, it is necessary to inspect to detect whether the insulation is defective. Therefore, according to the present embodiment, the number of inspections for defect analysis processing is increased by one compared to the conventional case.
[0072]
However, as described above, in general, M = 500 to 2000, and only increases once for C = 251 to 1001. In addition, since the yield of printed circuit board manufacturing is high, the frequency of performing defect analysis processing is very low, and the effect of increasing the number of inspections for defect analysis processing does not become significant.
[0073]
Next, a modified embodiment in which the connection state switching procedure is different from the above embodiment will be described with reference to FIGS. 4 and 5 are flowcharts showing a connection state switching procedure in the modified embodiment. FIG. 6 is a diagram for explaining the switching of the connection state of the electrodes connected to each head pin in the modified embodiment. The “●” mark corresponding to each head pin indicates the state connected to the positive electrode 41 and the “◯” mark indicates the negative electrode 42 The connected state is shown.
[0074]
In FIG. 4, first, the first head pin P1 is connected to the positive electrode 41, and the second and third head pins P2, P3 are connected to the negative electrode 42 (step # 300). Is determined (step # 310). That is, the first inspection in FIG. 6 is performed.
[0075]
If not defective (NO in step # 310), the first to third head pins P1 to P3 are connected to the positive electrode 41, and the fourth to Mth (M is an integer of 6 or more). Thus, in this modification, for example, M = 10) head pins P4 to P10 are connected to the negative electrode 42 (step # 320), and the insulation state is determined (step # 330). That is, the second inspection in FIG. 6 is performed.
[0076]
If not defective (NO in step # 330), the third to fifth head pins P3 to P5 are connected to the positive electrode 41 and the second and sixth to Mth in FIG. With the head pins P2, P6 to P10 being connected to the negative electrode 42 (step # 340), the insulation state is determined (step # 350). That is, the third inspection in FIG. 6 is performed.
[0077]
The steps after step # 360 are exactly the same as the steps after step # 140 in FIG.
That is, steps # 360 to # 380 correspond to, for example, the transition from the third inspection to the fourth inspection in FIG. 6, and only two head pins connected to the positive electrode 41 are directed to the Mth. When slid as it is, the head pins connected to the positive electrode 41 are switched from the head pins P1 to P3 to the head pins P3 to P5. As a result, the number of head pins connected to the positive electrode 41 remains three, and the head pins P6 to P10 remain on the Mth side. The same applies when moving from the fourth inspection to the fifth inspection.
[0078]
Steps # 380 and # 390 correspond to the fourth and fifth connection states in FIG. 6, and steps # 370 and # 420 correspond to the sixth connection state in FIG.
[0079]
Next, with reference to FIG. 6, a description will be given of the fact that the insulation inspection of all head pin combinations becomes possible by switching the connection state.
In the first inspection, the insulation state between the head pin P1 and the head pins P2 and P3 is inspected.
[0080]
In the second inspection, an inspection of the insulation state between the head pins P1 to P3 and the head pins P4 to P10 is performed. Thereby, the insulation test of the head pin P1 is completed. Note that the insulation state between the head pin P2 and the head pin P3 remains unclear.
[0081]
In the third inspection, an inspection of the insulation state between the head pins P3 to P5 and the head pins P2 and P6 to P10 is performed. Therefore, if this inspection result is good, it is confirmed that the insulation state between the head pin P2 and the head pin P3 is good, and the insulation inspection of the head pins P2 and P3 is completed. The insulation state between the head pin P4 and the head pin P5 remains unclear.
[0082]
Similarly, in the fourth inspection, if the inspection result is good, it is confirmed that the insulation state between the head pin P4 and the head pin P5 is good, and the insulation inspection of the head pins P4 and P5 is performed. It will be completed.
[0083]
In the fifth inspection, if the inspection result is good, it is confirmed that the insulation state between the head pin P6 and the head pin P7 is good, and the insulation inspection of the head pins P6 and P7 is completed. It becomes. In the fifth inspection, the insulation state between the head pin P8 and the head pin P9 remains unknown, but the insulation inspection of the head pin P10 is completed.
[0084]
And if the inspection result is good in the sixth inspection, it is confirmed that the insulation state between the head pin P8 and the head pin P9, which was unknown in the fifth inspection, is good. The insulation inspection of the head pins P8 and P9 is completed.
[0085]
In this way, there are three adjacent head pins connected to the positive electrode 41, and two of them are slid toward the Mth side, and one headpin adjacent to the first side is connected to the negative electrode 42. As a result, the insulation state of the head pin, which was unknown in the previous inspection, can be confirmed.
[0086]
As a result, the first head pin insulation inspection is completed in the second inspection, two head pin insulation inspections are completed in the third to sixth inspections, and the tenth in the fifth inspection. Insulation inspection is completed with a total of 6 inspections, and the number of inspections is greatly reduced as in the above embodiment, compared to the conventional number of inspections 9 times. Can do.
[0087]
Note that steps # 300 and # 320 in FIG. 4 may be performed according to the procedure shown in FIG. That is, the first and second insulation inspections may be performed in a connection state as shown in FIG. 8 instead of FIG.
In the first insulation test in FIG. 8 (step # 300 in FIG. 7), the first head pin P1 is connected to the positive electrode 41 and the second to Mth head pins P2 to P10 are connected to the negative electrode 42. To do. In the second insulation test (step # 320 in FIG. 7), the second and third head pins P2 and P3 are connected to the positive electrode 41, and the fourth to Mth head pins P4 to P10. Is connected to the negative electrode 42. Then, after the third time, the inspection is performed in the same connection state as in FIGS.
[0088]
That is, in the present modification, when the second to Mth head pins P2 to P10 are connected to the negative electrode 42 in the first inspection, the second inspection is completed when the insulation inspection for the first head pin P1 is completed. It is not necessary to connect the first head pin P1 to the positive electrode 41 in each inspection.
[0089]
Next, the number C of inspections when the number of head pins is M in this modification will be described.
First, when the number M of the head pins is an even number, as described above, the inspection of the first head pin is completed in the second inspection, and two by two in the third to C inspections. . Here, the insulation inspection of the (M-2) th and (M-1) th head pins is completed in the Cth inspection, and the Mth headpin inspection is completed in the (C-1) th inspection. Is completed, so the number of inspections C is
[0090]
[Expression 4]
C = (M−2) / 2 + 2
It becomes. The second term on the right side of Equation 4 corresponds to the first and second inspections.
[0091]
On the other hand, when the number M of the head pins is an odd number, the final number of times that the insulation inspection of the (M−1) th and Mth head pins is completed. Therefore, when the number M of head pins is an odd number, the number is equal to the number of inspections when the number of head pins is (M + 1). Therefore, the number of inspections C is
[0092]
[Equation 5]
C = (M−1) / 2 + 2
It becomes.
[0093]
As described above, since M = 500 to 2000, normally, according to the present embodiment, C = 251 to 1001, and the number of inspections can be greatly reduced as in the above embodiment.
[0094]
Note that the shape of the wiring pattern of the printed circuit board 20 to be inspected is not limited to FIG. 9, and any shape can be inspected.
[0095]
3, 6, and 8 indicate a state in which the “●” mark is connected to the positive electrode 41 and a state in which the “◯” mark is connected to the negative electrode 42, but the present invention is not limited thereto. , “●” mark may indicate a state connected to the negative electrode 42, and “◯” mark may indicate a state connected to the positive electrode 41.
[0096]
As described above, in the present invention, the connection state to the pair of electrodes is basically a 2-pin-to-multi-pin insulation test, as shown in the above formulas 2, 3, 4 and 5. Yes.
[0097]
For example, in FIG. 3, in the first inspection, a two-pin vs. multi-pin inspection is performed, and therefore the insulation state between the two pins is unknown. In the second and subsequent inspections, the following two-pin-to-multi-pin inspection is performed, and an insulation inspection between two pins that was previously unknown is performed. That is, in the first inspection, the inspection between the head pins P1, P2 and the remaining pins is performed, and the insulation state between the head pins P1, P2 is unknown. In the second inspection, the inspection between the next head pins P3 and P4 and the remaining pins is performed, and the inspection between the head pins P1 and P2 is performed. As a result, in the second and subsequent inspections, the inspection is completed by two pins.
[0098]
For example, in FIGS. 6 and 8, the inspection of the head pin P1 is completed in the first and second inspections, and the inspection of 2 to many pins is performed in the second inspection. The insulation state of is unknown. In the third and subsequent inspections, the following two-pin-to-multi-pin inspection is performed, and an insulation inspection between two pins that was previously unknown is performed. That is, in the second inspection, the inspection between the head pins P2, P3 and the remaining pins is performed, and the insulation state between the head pins P2, P3 is unknown. In the third inspection, the next head pins P4 and P5 are inspected between the remaining pins and the head pins P2 and P3 are inspected. As a result, in the third and subsequent inspections, the inspection is completed by two pins each.
[0099]
As described above, according to the present invention, the number of switching of the connection state, that is, the number of inspections can be greatly reduced as compared with the conventional case by basically performing the insulation inspection of two pins to many pins.
[0100]
【The invention's effect】
As described above, according to the first and third aspects of the invention, from No. 1 to M-th respectively set at predetermined positions on M (M is an integer of 5 or more) wiring patterns formed on the substrate. Switch the connection state between the first pin and the second electrode that can be electrically connected to each representative pin, and send a predetermined electrical signal to one of the first electrode and the second electrode. When determining whether the insulation state between the representative pins connected to each electrode is good or bad based on the level of the electrical signal of the other electrode when applied, the first connection state The first and second representative pins are connected to the first electrode, and the third to Mth representative pins are connected to the second electrode. Connect the 4th representative pin to the 1st electrode and the 1st and 5th The M-th representative pin is connected to the second electrode, and the second and subsequent connection states are slid by two representative pins connected to the first electrode from the second connection state toward the M-th side. In addition, one representative pin adjacent to the first side and all the representative pins on the Mth side are connected to the second electrode with respect to the representative pin connected to the slid first electrode, and the first electrode Since the switching is completed when the number of representative pins to be connected is less than three, the number of switching of the connection state for determining the insulation state between all the representative pins should be reduced. As a result, the insulation inspection time can be shortened.
[0101]
According to the second and fourth aspects of the present invention, representatives from No. 1 to No. M respectively set at predetermined positions on M (M is an integer of 6 or more) wiring patterns formed on the substrate. When the connection state between the pin and the first electrode and the second electrode that can be electrically connected to each representative pin is switched, and a predetermined electrical signal is applied to one of the first electrode and the second electrode When determining whether the insulation state between the representative pins connected to each electrode is good or bad based on the level of the electrical signal of the other electrode for each switching of the connection state, the first connection state is the first connection state. The second representative pin is connected to the first electrode, and the second and third representative pins or all the second to M-th representative pins are connected to the second electrode. In the first connection state, only the second and third representative pins are used as the second electrode. When connected, the 1st to 3rd representative pins are connected, and when all the 2nd to Mth representative pins are connected to the second electrode in the initial connection state, the 2nd and 3rd representative pins are connected. The representative pins are connected to the first electrode, the fourth to Mth representative pins are connected to the second electrode, and the third to fifth representative pins are connected as the third connection state. Connect to the 1st electrode, connect the 2nd and 6th to Mth representative pins to the 2nd electrode, connect to the 1st electrode from the 3rd connection state as the 4th and subsequent connection states Each of the two pins is slid toward the Mth side, and one representative pin adjacent to the first side and the Mth side of the representative pin connected to the slid first electrode All representative pins are connected to the second electrode, and the number of representative pins connected to the first electrode is less than three. Since the switching is completed in the connected state, the number of switching of the connection state for determining the insulation state between all the representative pins can be reduced, thereby shortening the insulation inspection time. it can.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an electrical configuration of an embodiment of a substrate insulation inspection apparatus according to the present invention.
FIG. 2 is a flowchart showing a connection state switching procedure;
FIG. 3 is a diagram for explaining the switching of the connection state of the electrodes connected to each head pin. The “●” mark corresponding to each head pin indicates the state connected to the positive electrode, and the “◯” mark indicates the state connected to the negative electrode. Show.
FIG. 4 is a flowchart showing a connection state switching procedure in a modified embodiment;
FIG. 5 is a flowchart showing a connection state switching procedure in a modified embodiment;
FIG. 6 is a diagram for explaining the switching of the connection state of the electrodes connected to each head pin in a modified embodiment, where the “●” mark corresponding to each head pin indicates the state connected to the positive electrode and the “◯” mark connects to the negative electrode Shows the state.
7 is a flowchart showing a modification procedure of FIG. 4;
FIG. 8 is a diagram for explaining a modified connection state of FIG. 6;
FIG. 9 is a diagram illustrating an example of a printed circuit board to be inspected.
10 is a diagram showing an inspection net list of the printed circuit board of FIG. 9 and net pins to be subjected to continuity inspection. FIG.
FIG. 11 is a diagram for explaining a conventional insulation inspection procedure;
[Explanation of symbols]
30 Insulation inspection equipment for substrates
41 Positive electrode
42 Negative electrode
50 connections
60 Control means
61 Switching control means
62 Insulation determination means
63 Defect analysis control means
71 Signal applying means
72 Signal detection means
73 Level judgment means

Claims (4)

In a substrate on which M (M is an integer of 5 or more) wiring patterns are formed, the insulation state between the first to Mth representative pins set at predetermined positions on each wiring pattern is determined. A substrate insulation inspection device for inspecting an insulation state between the wiring patterns by inspecting,
A first electrode and a second electrode that can be electrically connected to the first to Mth representative pins, respectively;
Switching control means for controlling switching of the connection state between the first and second electrodes and the representative pins;
Insulation between representative pins connected to each electrode based on the level of the electric signal of the other electrode when a predetermined electric signal is applied to one of the first electrode and the second electrode Insulation determination means for determining whether the state is good or bad for each switching of the connection state,
The switching control means includes
As the first connection state, the first and second representative pins are connected to the first electrode, and the third to Mth representative pins are connected to the second electrode.
As the second connection state, the second to fourth representative pins are connected to the first electrode, and the first and fifth to Mth representative pins are connected to the second electrode.
As the connection state after the third time, two representative pins connected to the first electrode from the second connection state are slid toward the Mth side and connected to the slid first electrode. One representative pin adjacent to the first side with respect to the representative pin and all the representative pins on the Mth side are connected to the second electrode,
The substrate insulation inspection apparatus, wherein the switching is completed when the number of representative pins connected to the first electrode is less than three. In a substrate on which M (M is an integer of 6 or more) wiring patterns are formed, the insulation state between the first to Mth representative pins set at predetermined positions on each wiring pattern is determined. A substrate insulation inspection device for inspecting an insulation state between the wiring patterns by inspecting,
A first electrode and a second electrode that can be electrically connected to the first to Mth representative pins, respectively;
Switching control means for controlling switching of the connection state between the first and second electrodes and the representative pins;
Based on the level of the electrical signal of the other electrode when a predetermined electrical signal is applied to one of the electrodes, the connection state can be switched to determine whether the insulation state between the representative pins connected to each electrode is good or bad. Insulation determination means for determining for each,
The switching control means includes
As an initial connection state, the first representative pin is connected to the first electrode, and the second and third representative pins or all the second to M-th representative pins are connected to the second electrode. Connected to
As the second connection state, when only the second and third representative pins are connected to the second electrode in the first connection state, the first to third representative pins are connected in the first connection state. When all the 2nd to Mth representative pins are connected to the second electrode, the 2nd and 3rd representative pins are connected to the first electrode, respectively, and the 4th to Mth No. representative pin is connected to the second electrode,
As the third connection state, the third to fifth representative pins are connected to the first electrode, and the second and sixth to Mth representative pins are connected to the second electrode.
As the connection state after the fourth time, two representative pins connected to the first electrode from the third connection state are slid toward the Mth side and connected to the slid first electrode. One representative pin adjacent to the first side with respect to the representative pin and all the representative pins on the Mth side are connected to the second electrode,
The substrate insulation inspection apparatus, wherein the switching is completed when the number of representative pins connected to the first electrode is less than three. In a substrate on which M (M is an integer of 5 or more) wiring patterns are formed, the insulation state between the first to Mth representative pins set at predetermined positions on each wiring pattern is determined. A substrate insulation inspection method for inspecting an insulation state between each wiring pattern by inspecting,
Of the first electrode and the second electrode, the first and second electrodes that can be electrically connected to the first to Mth representative pins, respectively, and the representative pins are connected. Based on the electric signal level of the other electrode when a predetermined electric signal is applied to one electrode, it is determined whether the insulation state between the representative pins connected to each electrode is good or bad. ,
After performing the following steps (1) and (2) in this order, the following step (3) is repeated until the number of representative pins connected to the first electrode is less than three. Insulation inspection method for the substrate.
(1) connecting the first and second representative pins to the first electrode and performing the determination in a state where the third to Mth representative pins are connected to the second electrode;
(2) The second to fourth representative pins are connected to the first electrode, and the above determination is made with the first and fifth to Mth representative pins connected to the second electrode. Process to perform,
(3) Two representative pins connected to the first electrode are slid toward the Mth side, and adjacent to the first side with respect to the slid representative pins connected to the first electrode. Performing the determination in a state in which one representative pin and all the M-th representative pins are connected to the second electrode. In a substrate on which M (M is an integer of 6 or more) wiring patterns are formed, the insulation state between the first to Mth representative pins set at predetermined positions on each wiring pattern is determined. A substrate insulation inspection method for inspecting an insulation state between each wiring pattern by inspecting,
Of the first electrode and the second electrode, the first and second electrodes that can be electrically connected to the first to Mth representative pins, respectively, and the representative pins are connected. Based on the electric signal level of the other electrode when a predetermined electric signal is applied to one electrode, it is determined whether the insulation state between the representative pins connected to each electrode is good or bad. ,
After the following steps (1), (2) and (3) are executed in this order, the following step (4) is repeated until the number of representative pins connected to the first electrode is less than three. A method for inspecting insulation of a substrate, characterized in that:
(1) The first representative pin is connected to the first electrode, and the second and third representative pins or all the second to Mth representative pins are connected to the second electrode. Performing the above determination in a state,
(2) When only the second and third representative pins are connected to the second electrode in the step (1), the first to third representative pins are connected to the second pin in the step (1). When all the representative pins of No. M to No. M are connected to the second electrode, the No. 2 and No. 3 representative pins are respectively connected to the first electrode, and the No. 4 to No. M pins are connected. Performing the determination in a state where the representative pin is connected to the second electrode;
(3) The third to fifth representative pins are connected to the first electrode, and the second and sixth to Mth representative pins are connected to the second electrode. Process to perform,
(4) Two representative pins connected to the first electrode are slid toward the Mth side and adjacent to the first side with respect to the slid representative pins connected to the first electrode. Performing the determination in a state in which one representative pin and all the M-th representative pins are connected to the second electrode.

Images