JP3161047B2 - Inspection equipment for printed wiring boards - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting the performance of a printed wiring board.

[0002]

2. Description of the Related Art Generally, a printed wiring board on which an integrated circuit or the like is mounted is electrically connected to the printed circuit board before mounting the integrated circuit or the like in order to confirm that a wiring pattern of the printed wiring board has an expected performance. It is necessary to check the characteristics. Conventionally, as a method of performing an inspection of this printed wiring board, basically, an inspection electrode arranged according to the arrangement pattern of the electrodes to be inspected of the inspected printed wiring board is provided, and the inspection electrode is formed by wire wiring. A method using an individually corresponding test electrode device electrically connected to a test circuit of a tester, and a test electrode device in which test electrodes are formed at standard lattice points arranged in rows and columns, called a universal type, are applied to the tester. There is known a method of using an electrode to be inspected on an inspection printed wiring board in combination with a connector for connecting the inspection electrode of the inspection electrode device.

At present, in the field of printed wiring boards,
There is a tendency that the degree of integration of elements and the density of patterns are further promoted, and accordingly, the density of inspection electrodes is also required in inspection electrode devices. However,
Inspection electrode devices of the individually compatible type require test electrodes in a pattern corresponding to the electrodes to be inspected on the printed wiring board to be inspected, so that the inspection circuit can be used more efficiently than the universal type. On the other hand, after all, it is necessary to form a high-density test electrode in the same manner as the test target electrode using a spring probe or the like. Therefore, it is difficult to manufacture the test electrode device, and the cost is extremely high. There are problems that can be problematic.

In a universal type test electrode device, the distance between adjacent test electrodes paired with a test circuit of a tester is fixed, and a test target having a high-density test electrode is tested. In order to inspect the printed wiring board, some of the electrodes to be inspected may be electrically connected to the inspection electrode at the closest position in the inspection electrode device. However, it is often necessary to electrically connect some of the other electrodes to be inspected to the inspection electrodes at a considerably separated position in the inspection electrode device. This is because the density of the electrode to be inspected is considerably higher than the density of the inspection electrode. And as a result,
Although it is necessary to increase the wiring density in the connector, there is a limit to the increase in the wiring density. In addition, there is a problem that many test electrodes that cannot be used effectively remain in practice, and that there is much waste in efficiency and as a device.

[0005]

As described above, it is difficult for the conventional printed wiring board inspection apparatus to sufficiently cope with the desired high density of the electrodes to be inspected. The configuration of the inspection electrode device becomes complicated, and it is difficult to sufficiently achieve a high density of wiring patterns in a connector for achieving electrical connection, so that highly reliable inspection cannot be performed.

SUMMARY OF THE INVENTION It is an object of the present invention to enable an electrical connection to a test circuit of a tester to be achieved with high efficiency and ease, and to provide a high reliability with sufficiently high reliability. An object of the present invention is to provide a printed wiring board inspection apparatus capable of inspecting a densified printed wiring board.

Another object of the present invention is to provide a high-efficiency electrical connection of a tester to a test circuit even when a printed wiring board has electrodes to be tested on both surfaces thereof. It is an object of the present invention to provide a printed wiring board inspection apparatus capable of inspecting a high-density printed wiring board with high reliability.

Still another object of the present invention is to provide an inspection apparatus for a printed wiring board which can easily replace and use a different inspection mechanism of an electrical connection system for an electrode to be inspected on a printed wiring board to be inspected. It is in.

[0009]

The printed wiring board of the present invention
The inspection device, and the off-grid adapter disposed objective printed wiring board to be inspected, and a test head arranged on the off-grid adapter, the off-grid adapter on the surface, the inspection A pitch conversion board having a surface electrode of a pattern corresponding to the electrode to be inspected of the printed wiring board and having, on the back surface, a back electrode arranged at a grid point position electrically connected to the front electrode; A first anisotropic conductive sheet disposed between the surface of the board and the printed wiring board to be inspected, wherein the inspection head comprises a second anisotropic conductive sheet;
Printed wiring via the second anisotropic conductive sheet comprising and a test electrode plate device having inspection electrodes of the lattice array which is electrically connected to the backside electrode of the pitch conversion board
In the wire plate inspection device, the inspection electrode plate device includes a plurality of inspection electrode plate devices.
Functional areas, each of which is identical to each other
The test electrodes are arranged in
Common electrode is formed inspection electrodes arranged in a corresponding position in the band and other functional areas are electrically connected to each other
It is characterized by having been done.

In the printed wiring board inspection apparatus according to the present invention, the off-grid adapter and the inspection head are provided on both sides of the printed wiring board to be inspected, respectively. The common electrode in one test electrode plate device related to the test head is electrically connected to the common electrode in the other test electrode plate device related to the other test head on the other surface side of the printed wiring board to be tested. The test electrodes related to the two common electrodes that are electrically connected to each other are located in one of the test electrode plate devices and the other test electrode plate device, which are located in non-overlapping regions. It is characterized by.

Further, the printed wiring board inspection apparatus of the present invention has a pressing mechanism including a pressing plate for pressing the off-grid adapter and the inspection head against the printed wiring board to be inspected. It is characterized in that it is provided detachably on the mechanism.

[0012]

According to the above construction, the inspection electrode which is electrically connected to a certain electrode to be inspected on the inspection target printed wiring board is present in any of the plurality of functional areas of the inspection electrode plate device. Electrical connection with the test circuit of the tester can be made with great flexibility, the number of terminals to be connected to the test circuit of the tester is greatly reduced, and the test electrode in each functional area is shared with the common electrode. By doing so, the utilization efficiency of the entire inspection electrode is increased.

[0013] In addition, in each of the inspection electrode plate devices provided on both surfaces of the printed wiring board to be inspected, the inspection electrodes related to the common electrode in the divided area that does not overlap vertically are electrically connected to each other to perform one inspection. A greater degree of freedom can be obtained in the electrical connection between the electrodes and the test circuit of the tester, and the number of connections to the test circuit can be reduced.

Further, the inspection head and the off-grid adapter can be removed by providing the inspection head detachably in a pressing mechanism for pressing the inspection electrode plate device related to the inspection head. It is possible to easily substitute and use a different inspection mechanism of the electrical connection system for the electrode to be inspected of the inspection printed wiring board.

[0015]

FIG. 1 is an explanatory sectional view showing the structure of a main part of an example of a printed wiring board inspection apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes a printed wiring board to be inspected, and electrodes 2 to be inspected are formed on both surfaces thereof. An inspection head 20 is arranged on the upper surface side and the lower surface side of the printed wiring board 1 via the off-grid adapter 10, respectively.

The off-grid adapter 10 includes a pitch conversion board 13 and a first anisotropic conductive sheet 14 disposed between the pitch conversion board 13 and the printed wiring board 1 to be inspected. On the surface of the pitch conversion board 13 on the side of the inspected printed wiring board 1, a surface electrode 11 having a pattern corresponding to the electrode 2 to be inspected of the inspected printed wiring board 1 is formed. On the back surface, a back electrode 12 electrically connected to the front electrode 11 is formed in a state of being arranged at lattice point positions.

The inspection head 20 includes an inspection electrode plate device 22
And the inspection electrode plate device 22 and the pitch conversion board 1
3 and a second anisotropic conductive sheet 23 disposed between the first electrode 3 and the second electrode 3. That is, the inspection electrodes 21 formed in a state of being arranged at all of the lattice point positions are formed. In the test electrode plate device 22, as will be described later, in order to reduce the number of test points so as to correspond to the number of electrodes of the test circuit 30 of the tester, a wiring circuit 28 for using each test electrode 21 as a common electrode is provided. An external lead terminal 29 is formed at one end of the inspection electrode plate device 22 by a part of the wiring circuit 28, and each terminal of the external lead terminal 29 is detachably connected. The connector 25 is connected to the test circuit 30 of the tester.

Reference numeral 31 denotes a pressing plate for pressing the test electrode plate device 22 of the test head 20 on the upper surface side downward.
It is provided detachably on a pressing mechanism (not shown). The pressing plate 31 is provided so as to be able to adjust a reference level in the pressing direction (downward in the figure), that is, a reference level at which the pressing operation has not been started. A receiving plate 32 made of an elastic cushioning material is arranged on the lower surface of the inspection electrode plate device 22 on the lower surface side.

Inspection electrode plate device 2 in inspection head 20
FIG. 2 shows a test electrode element 26 used as the test electrode plate device 22. The inspection electrode element 26 is configured such that an inspection electrode p is formed on one surface of a rectangular plate-shaped insulative base in accordance with a so-called universal arrangement at standard lattice points arranged vertically and horizontally. The inspection electrode element 26 has a total of four functional areas A, B, C, and D (an upper left in FIG. 2, (In the order of upper right, lower left, and lower right), and in each of the functional regions A to D, the inspection electrodes p arranged in the same arrangement vertically and horizontally in the same arrangement.
Having.

Now, in each of the functional areas A to D, the length m
In order to specify the inspection electrode p located at a specific position in the rows and n columns, the inspection electrode p at the position of the mth row and the nth column is specified.
Is designated as (m, n), and when the function area is further specified, symbols A to D indicating the function area are added to the head of the address display. For example, the test electrode in the first row and first column in the functional area A is A (1,
It is represented by 1).

Functional areas A to D of test electrode element 26
Are electrically connected to each other by a connection member. That is, there are a total of four test electrodes p having the same address indication (m, n) in each of the functional areas A to D, but the four test electrodes p having the same address indication are electrically connected to each other. The connection is made. The test electrodes electrically connected to each other are referred to as “common electrodes” in this specification,
It is represented by P (m, n). Therefore, one common electrode P (m, n) is connected to the test electrodes A (m, n) and B (m, n) as four branched terminals that are electrically connected.
n), C (m, n) and D (m, n).

The electrical connection of the test electrodes having the same address indication (m, n) may be achieved by appropriate connection members, and the specific configuration and means are not limited. . In the test electrode plate device 22 in the embodiment of FIG. 1, the test electrode element 26 as described above is used.
The connection member is formed by forming the wiring circuits 28 in multiple layers on the insulating base described above, but the connection member may be formed by an appropriate lead wire. Then, the inspection electrode p of the inspection electrode element 26 forms the inspection electrode 21 of the inspection electrode plate device 22.

Both the first anisotropic conductive sheet 14 and the second anisotropic conductive sheet 23 in the illustrated example have conductivity in the thickness direction of the sheet. Then, the second anisotropic conductive sheet 23 is provided on the inspection electrode 2 of the inspection head 20.
Numerous conductive path forming portions 24 arranged at positions corresponding to 1
Are formed in at least one surface in a protruding shape in the thickness direction, and have a function of improving electrical contact stability.

In the inspection apparatus for a printed wiring board having the above configuration, the printed wiring board 1 to be inspected is interposed between the pressing plate 31 of the pressing mechanism and the receiving plate 32 via the off-grid adapter 10 and the inspection head 20. Is pressed, each of the electrodes 2 to be inspected of the inspected printed wiring board 1 is located at a position corresponding to the inspection electrode 21 of the inspection head 20.
It is electrically connected to the, thereby, the desired inspection in a state of being electrically connected to the test circuit 30 of the tester is performed. In this pressed state, the lower receiving plate 3
Since 2 is made of an elastic cushioning material, the pressing force applied to the inspection head 20 and the off-grid adapter 10 by the pressing plate 31 has a uniform pressure distribution as a whole.

In the inspection electrode plate device 22 of the inspection head 20, the inspection electrodes 21 are formed in the same arrangement state in the plurality of functional areas, and the inspection electrodes 21 at the corresponding positions in the respective functional areas are formed. Since the electrodes 21 are electrically connected to each other by the wiring circuit 28 to form a common electrode, the test electrodes 21 that are electrically connected to a certain test target electrode 2 are present in each of the functional regions. The electrical connection between the electrode 2 and the test circuit 30 of the tester can be made with a large degree of freedom, and the number of terminals to be connected to the test circuit 30 of the tester may be the number of common electrodes. Significantly reduced compared to the total number of
As a result, even if the electrode 2 to be inspected on the inspected printed wiring board 1 is formed in a highly densified state at a specific location, the common electrode of the functional region separated from the location In other words, by using the test electrodes at positions dispersed by the common electrode,
The required electrical connections can be easily achieved and a highly reliable test can be performed.

In the inspection electrode plate device 22, the inspection electrode p in each functional area of the inspection electrode element 26 is used as a common electrode.
Since the use efficiency of the entire inspection electrode p is increased, unnecessary inspection electrodes are significantly reduced, and the inspection can be performed with extremely high efficiency.

FIG. 3 shows another embodiment of the present invention. In this figure, one test electrode plate device 50 arranged on the upper surface side of the printed wiring board 1 to be inspected, the other test electrode plate device 60 arranged on the lower surface side of the printed wiring board 1 to be inspected, and related parts thereof Only shown. In this example, one test electrode plate device 50 is formed with two functional regions 50A and 50B arranged in one direction (the X direction in the drawing), and the functional regions 50A and 50B have the same arrangement state. An inspection electrode p is formed, and each functional region 5
Inspection electrodes p at the same position in 0A and 50B, for example, inspection electrode 50A (1, 1) in functional area 50A
The test electrode 50B (1, 1) in the functional region 50B is electrically connected by the connection member 51. In FIG. 3, the connection member 51 is shown as being made of wire, but it is actually preferable to use a multilayer wiring circuit as described above.

Also, in the other inspection electrode plate device 60, the same as in the one inspection electrode plate device 50,
Two functional regions 60A and 60B arranged in the X direction are formed. In each functional region 60A and 60B, the inspection electrodes p at the same position are electrically connected by the connection member 61.

The common electrode of one test electrode plate device 50 is further electrically connected to the common electrode of the other test electrode plate device 60 by the second connecting member 70. The test electrodes related to the two common electrodes electrically connected to each other by the second connection member 70 in this manner are sections of the one test electrode plate device 50 and the other test electrode plate device 60 that do not vertically overlap each other. It is located in the area.

For example, in FIG. 3, one of the inspection electrode plate devices 50 is, as indicated by the division line D, placed in two similar division regions 50a and 50b arranged in the Y direction perpendicular to the X direction. In addition to the division, the other inspection electrode plate device 60 is similarly divided into two similar division regions 60a and 60b arranged in the Y direction. Here, in the example of the figure, for the sake of explanation, each of the divided regions is in a state where 11 inspection electrodes p are present.

The other test electrode plate device 6 which does not vertically overlap the defined area 50a of one test electrode plate device 50
0 and the divided area 50b
The test electrodes p related to the common electrodes in the corresponding order are electrically connected to each other in the partition region 60a. In the drawing, the test electrode 50B (1, 1) belonging to the functional area 50B and belonging to the partitioned area 50a and the test electrode 60B (1, 12 ) belonging to the functional area 60B and belonging to the partitioned area 60b are electrically connected by the connecting member 70A. And a test electrode 50A belonging to the functional area 50A and belonging to the partitioned area 50b.
(1, 12 ) and the test electrodes 60A (1, 1) belonging to the functional area 60A and belonging to the partitioned area 60a are electrically connected by the connecting member 70B. Then, the other test electrodes p are similarly electrically connected by the second connection member 70.

In this embodiment, each of the test electrode plate devices 50 and 60 has two functional areas, and the corresponding test electrodes between the functional areas are electrically connected to each other. Since the test electrodes related to the common electrode in the divided regions that do not overlap vertically are electrically connected between the test electrode plate device 50 and the other test electrode plate device 60, the above-described point is also applied to this point. According to the same principle as in the case of the common electrode, a large degree of freedom can be obtained in the electrical connection between one test electrode p and the test circuit 30 of the tester, and the number of connections to the test circuit 30 can be reduced. it can.

In this example, since each of the test electrode plate devices 50 and 60 has two functional areas, the connection for electrical connection between the corresponding test electrodes between the functional areas is performed. The arrangement of the members 51 and 61 is easy, and it can be easily realized as a multilayer wiring circuit.

In the above, the actual second connecting member 70
Is electrically connected to the test circuit 30 of the tester, for example.
It can also be implemented in the wiring of the electrical path leading to.
That is, the wiring from one test electrode plate device 50 to the test circuit 30 of the tester and the wiring from the other test electrode plate device 60 to the test circuit 30 of the tester may be connected at appropriate positions. Further, this electrical connection can be realized in the test circuit 30 of the tester. As described above, when the electrical connection by the second connection member is achieved on the wiring, it is not necessary to actually provide the second connection member between the inspection electrode plate devices. The configuration in the space between the heads 20 is not complicated.

As described above, a pressing plate for pressing the inspection electrode plate device 22 of the inspection head 20 on the upper surface side constituting the inspection device downward is provided detachably on the pressing mechanism. In addition, since the inspection head 20 and the off-grid adapter 10 can be removed, different inspection mechanisms of the electrical connection system for the electrodes to be inspected on the inspected printed wiring board can be easily replaced and used. The advantage of a simple inspection mechanism can be effectively utilized.

For example, as shown in FIG.
In 2, the spring probe 41 is arranged corresponding to the arrangement pattern of the electrode 2 to be inspected on the inspected printed wiring board 1, and the spring probe 41 is electrically connected to the inspection circuit 30 of the tester by the wire wiring 43 and used. Although the individualized inspection mechanism 80 is widely used, it is easy to replace and use such an individualized inspection mechanism 80 instead of the inspection head 20 and the off-grid adapter 10, Useless or degraded existing equipment is avoided.

As described above, when another inspection mechanism having a different electrical connection system is used instead, the pressing plate 31 is provided so that the reference level in the pressing direction (downward in the figure) can be adjusted. Thus, the pressing mechanism can be used sufficiently and reliably even when the other inspection mechanisms have different overall thicknesses. Further, by making the connector 25 detachable, it is possible to commonly use a mechanism for connecting the tester to the inspection circuit.

[0038]

The inspection of the printed wiring board according to the first aspect of the present invention.
The device uses a pitch conversion button on the off-grid adapter.
To the electrodes to be inspected on the printed wiring board to be inspected.
Having a corresponding pattern of surface electrodes
It is basically a personalized inspection system , and
Correspondence in each of multiple functional areas in the inspection head
Test electrodes are electrically connected to each other,
By being formed, in the inspection electrode plate device
Is connected to an electrode to be inspected of the printed circuit board to be inspected.
Test electrodes exist in each functional area,
As a result, the electrical connection between the electrode to be inspected of the printed circuit board to be inspected and the inspection circuit of the tester can be easily achieved with high efficiency and with a large degree of freedom, and the density is increased with sufficiently high reliability. Inspection of printed wiring boards
Can be .

In addition, although the inspection head uses the inspection electrode plate device in which the inspection electrodes are arranged in the universal arrangement, the inspection electrodes form a common electrode, so that the inspection in the universal arrangement is performed. Yes of the electrodes
The number of things that are not used effectively decreases and they are used effectively
Because the number of things increases, the inspection of the printed circuit board
The density of the electrodes to be inspected in the inspection area is the same
As compared with the case where the common electrode is not formed, it is possible to inspect the inspected electrode in the inspected region with the inspected region having a larger area as an inspection target , and
An off-grid adapter using an anisotropic conductive sheet can inspect a printed wiring board with high reliability.

According to the second aspect of the present invention, even when the printed wiring board has the electrodes to be inspected on both sides thereof, the inspection electrode plate devices provided on both sides of the inspected printed wiring board do not overlap vertically. By electrically connecting the test electrodes related to the common electrode of the divided area, a greater degree of freedom is obtained in the electrical connection between the test electrode and the test circuit of the tester, and a connection terminal for the test circuit is provided. The number can be reduced.

According to the third aspect of the present invention, the inspection head and the off-grid adapter can be removed by providing the inspection head in a pressing mechanism for pressing the inspection electrode plate device related to the inspection head in a detachable manner. Since it becomes possible, it is possible to easily substitute and use a different inspection mechanism of the electrical connection system for the electrode to be inspected of the inspected printed wiring board.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a configuration of a main part in an embodiment of a printed wiring board inspection apparatus according to the present invention.

FIG. 2 is an explanatory diagram of a test electrode element used as the test electrode plate device in FIG.

FIG. 3 is an explanatory diagram showing a configuration of two inspection electrode plate devices according to another embodiment of the present invention.

FIG. 4 is an explanatory diagram illustrating a configuration of an example of an individualized inspection mechanism.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 printed wiring board to be inspected 2 electrode to be inspected 10 off-grid adapter 11 front electrode 12 back electrode 13 pitch conversion board 14 first anisotropic conductive sheet 20 inspection head 21 inspection electrode 22 inspection electrode plate device 23 second anisotropic Conductive sheet 24 Conductive path forming part 25 Connector 26 Test electrode element 28 Wiring circuit 29 External lead-out terminal part 30 Test circuit 31 Press plate 32 Elastic buffer material 41 Spring probe 42 Terminal holding plate 43 Wire wiring 50 One test electrode plate device 50A , 50B
Functional area 50a, 50b Partition area 60A, 60B
Function area 60a, 60b Partition area 51 Connection member 60 The other inspection electrode plate device 61 Connection member 70, 70A, 70B Second connection member 80 Individually compatible inspection mechanism p Inspection electrode A, B, C, D Functional area

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01R 31/28-31/3193 G01R 31/02

Claims (3)

(57) [Claims] 1. An off-grid adapter arranged on a printed wiring board to be inspected and an inspection head arranged on the off-grid adapter , wherein the off-grid adapter has a surface to be inspected. A pitch conversion board having a surface electrode of a pattern corresponding to the electrode to be inspected of the printed wiring board and having, on the back surface, a back electrode arranged at a grid point position electrically connected to the front electrode; A first anisotropically conductive sheet disposed between the surface of the board and the printed wiring board to be inspected, wherein the inspection head comprises a second anisotropically conductive sheet and the second anisotropically conductive sheet. A test electrode plate device having a grid-like arrangement of test electrodes electrically connected to a back electrode of the pitch conversion board via a conductive sheet.
In the inspection device, the inspection electrode plate device has a plurality of functional areas.
Inspection electrodes are arranged in the same
Together is, inspection of the printed wiring board, wherein a common electrode corresponding disposed positions the inspection electrodes is electrically connected to each other are formed in one functional area and other functional areas apparatus. 2. An off-grid adapter and an inspection head according to claim 1 are provided on both surfaces of a printed wiring board to be inspected, respectively, and one inspection is performed on one inspection head on one surface side of the printed wiring board to be inspected. The common electrode in the electrode plate device is electrically connected to the common electrode in the other inspection electrode plate device related to the other inspection head on the other surface side of the printed wiring board to be inspected, and is electrically connected to each other. Wherein the test electrodes related to the two common electrodes are located in partitioned areas of the one test electrode plate device and the other test electrode plate device that do not vertically overlap each other. Inspection equipment. 3. A pressing mechanism including a pressing plate for pressing the off-grid adapter and the inspection head against a printed wiring board to be inspected, wherein the inspection head is detachably provided on the pressing mechanism. The inspection apparatus for a printed wiring board according to claim 1, wherein: