JP2814869B2 - Circuit board inspection method and circuit board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board inspection method for inspecting a mounted circuit board on which surface-mounted circuit components are mounted, and a circuit board suitable for performing the inspection method.

[0002]

2. Description of the Related Art In a mounted circuit board on which circuit components are mounted, the inspection of a mounted circuit board for inspecting the quality of circuit components, wiring patterns, and connections between them is performed by an inspection provided in an in-circuit tester (inspection apparatus). This has been conventionally performed by pressing a pin (probe) against a terminal portion of a circuit component. FIG. 5 is an explanatory diagram for explaining this conventional inspection method. The mounted circuit board 10 includes a circuit board 1 having a predetermined wiring pattern 3 disposed on a main surface of a circuit board body 2;
Circuit components 4 and 5 mounted on the circuit board 1 are provided. The pins 4b and 5b provided on the circuit components 4 and 5 are soldered to predetermined portions of the wiring pattern 3, so that the circuit components 4 and 5 are mounted at predetermined positions on the circuit board 1. The circuit components 4 and 5 are mounted such that the main bodies 4a and 5a are located on the surface of the circuit board main body 2, that is, on the component surface (first main surface) 2a.

The discrete component 4 in the circuit components 4 and 5 is connected to the back surface of the circuit board main body 2, that is, the solder surface (the second surface).
This is a circuit component in which the tip of the pin 4b is exposed on the main surface 2b. In the mounted circuit board 10 on which only the discrete component 4 is mounted, the inspection is performed by pressing each of the pair of inspection pins 6a and 6b into contact with a portion of the pin 4b exposed on the solder surface 2b. I was On the other hand, in the mounted circuit board 10 on which the surface mount component (surface mount type circuit component) 5 in which the pin 5b is not exposed to the solder surface 2b, the inspection pins 6a and 6b are pressed against the pin 5b of the surface mount component 5. Inspection of the quality of the surface-mounted component 5 has been performed.

[0004]

Since the inspection of the mounted circuit board 10 on which the surface mount components 5 are mounted has been performed by the above-described method, first, the inspection pins 6a and 6b are
It is necessary to press not only on the solder surface 2b but also on the component surface 2a, so that the inspection process has to be complicated. Further, since it is necessary to configure a jig of the inspection device to inspect both surfaces, there is a problem that the cost of the inspection device is increased.

[0005] Second, as the fine pitch of the surface mount component 5 has advanced in recent years, the inspection pins 6a, 6
There is a problem that it is difficult to perform the inspection using b with high accuracy. For this reason, a situation has arisen in which shipment has to be carried out while leaving parts that cannot be inspected.
There has been a problem that contact failure between the surface mount component and the wiring pattern is frequently occurring.

Third, as schematically shown in FIG. 6, even when the connection between the pin 5b and the wiring pattern 3 is not satisfactorily connected due to a solder defect, that is, in the case of so-called "lead floating", the inspection pin 6a , 6b, the pin 5b and the wiring pattern 3 may be temporarily connected at the time of inspection. For this reason, there is a problem that a circuit portion that should be determined to be defective is erroneously determined to be acceptable.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a circuit board inspection method capable of inspecting a mounted circuit board with a simple process and with high accuracy of determination, and an inspection method for the same. An object is to provide a circuit board suitable for implementation.

[0008]

A circuit board inspection method according to the present invention is a circuit board inspection method for inspecting a mounted circuit board in which a plurality of circuit components including a plurality of surface mount circuit components are mounted on the circuit board. (A) the first and second
(B) providing a pair of probes, and detecting an electrical characteristic between the pair of probes that come into contact with the inspection object. A step of preparing an inspection device for inspecting the quality of the inspection object; and (c) disposing a wiring pattern to be electrically connected between the plurality of circuit components on at least the first main surface. And (d) providing a test pad of an electrical conductor substantially only on the first main surface of the wiring pattern, wherein the plurality of surface-mounted circuit components are provided. (E) installing the circuit component on the circuit board main body so as to be electrically connected to a portion connecting only between the components and to expose a part of the circuit component on the second main surface; The main body of each one is located on the first main surface side of the circuit board main body. Mounting a number of circuit components at predetermined positions on the circuit board body to form a mounted circuit board; and (f) connecting one of the pair of probes 1 to the test pad of the mounted circuit board. The other one is exposed to the second main surface of the mounting circuit board, and the other one is exposed to the second main surface of the test pad on the mounting circuit board, or the circuit component of the circuit component on the mounting circuit board is contacted. Inspecting the quality of the surface-mounted circuit component or a portion to be electrically connected to the surface-mounted circuit component on the mounted circuit board by contacting the portion exposed on the second main surface; It has. And before
The step (d) includes: (d-1) the step of forming the wiring pattern;
Forming a through-hole penetrating through the circuit board body.
And (d-2) attaching the inner surface to the inner surface of the through hole.
Form a member of the same material as the wiring pattern so as to cover
(D-3) before the member and the wiring pattern
And are made of the same material
Surrounding the opening of the through hole to the first main surface.
A first circular pattern is arranged on the first main surface in an annular shape.
(D-4) connected to the member, and
The same material as the member is used, and the second
An annular and isolated island surrounding the opening to the main surface
To Jo, disposing the second circle-shaped pattern on the second main surface
And a step, Ru equipped with.

A circuit board according to the present invention is a circuit board on which a plurality of circuit components including a plurality of surface mount type circuit components are to be mounted, wherein (a) a main body of each one of the plurality of circuit components is located at a position. (B) electrically connecting the plurality of circuit components in a predetermined manner with a circuit board body of an electrical insulator having a first main surface and a second main surface that are to be connected; A wiring pattern provided at least on the first main surface; and (c) a portion provided only on the first main surface of the wiring pattern, wherein A test pad electrically connected to a portion connecting only between the surface-mounted circuit components of the first embodiment, and a test pad installed on the circuit board body, and a part of which is exposed to the second main surface. And an electric conductor test pad . Soshi
And the test pad is (c-1) the wiring pattern
A through-hole passing through the portion and the circuit board body;
(C-2) The inner surface of the through hole is covered with the inner surface.
Parts formed of the same material as the wiring pattern
(C-3) the member and the portion of the wiring pattern
Connected to the minute, and made of the same material as these,
A circle surrounding the opening of the through hole to the first main surface.
A first circular putter annularly disposed on the first main surface;
(C-4) connected to the member, and the member
To the second main surface of the through hole
Into an annular and isolated island surrounding the opening
A second circular pattern disposed on the second main surface.
For example Ru.

[0010]

According to the circuit board inspection method of the present invention, in a mounting circuit board on which a surface mounting type circuit component is mounted, a first pattern in which a main body of the circuit component is located in a wiring pattern disposed on the mounting circuit board. A test pad electrically connected to a portion provided only on the main surface and connected only to the surface mount component is provided. The test pad is substantially conductive, and a portion of the test pad is a second one of the mounted circuit board.
Exposed on the main surface of The inspection of the mounted circuit board is performed by inspecting the portion exposed on the second main surface of the circuit component and the second portion of the test pad.
Is performed by bringing the probe of the inspection device into contact with any of the portions exposed on the main surface of the inspection device. For this reason, since the probe need only be brought into contact with the second main surface only, the inspection process is simplified. Further, since it is not necessary to bring the probe into contact with the surface-mounted component, a high-precision inspection can be performed even in the inspection of the mounted circuit board on which the surface-mounted component having the fine pitch is mounted. Further, since no pressure is applied to the surface-mounted component by the probe, a defective connection between the surface-mounted component and the wiring pattern can be detected without overlooking.

In the circuit board according to the present invention, the portion of the wiring pattern provided only on the first main surface where the body of the circuit component is to be located, and electrically connected to the portion connected only to the surface mount type component It has a test pad to connect. The test pad is substantially conductive and a part thereof is exposed on the second main surface of the mounting circuit board. For this reason, the inspection of the mounted circuit board formed by mounting the circuit component including the surface mount component on the circuit board is performed by inspecting the portion exposed on the second main surface of the circuit component and the test pad exposed on the same second main surface. This can be performed by bringing the probe of the inspection apparatus into contact with any of the portions to be inspected. Therefore, the inspection of the mounted circuit board can be performed with a simple process and with high accuracy.

[0012]

FIG. 2 is a front sectional view showing the structure of a mounted circuit board in which surface-mounted circuit components are mounted on a circuit board according to an embodiment of the present invention (FIG. 2).
(A)) and a plan view (FIG. 2 (b)). The mounted circuit board 20 has a circuit board 11 in which a predetermined wiring pattern 13 is provided on a main surface of a circuit board body 12, and circuit components mounted on the circuit board 11. FIG. 2 illustrates two surface-mounted components (surface-mounted circuit components) 21 and 22 mounted on the circuit board 11. Pins 21b and 22b respectively provided on surface mount components 21 and 22
Are soldered to predetermined portions of the wiring pattern 13 so that the surface mount components 21 and 22 are mounted at predetermined positions on the circuit board 11. In addition, surface mount component 2
Reference numerals 1 and 22 denote that the main body portions 21a and 22a are formed on the surface of the circuit board main body 12, that is, the component surface (first main surface)
It is mounted so as to be located on the a side. Surface mount component 2
Reference numeral 1 denotes, for example, a surface mount type capacitance element, and the surface mount component 22 is, for example, a surface mount type integrated circuit element. The wiring pattern 13 is made of, for example, a copper material, and is formed using, for example, a well-known printed wiring technique.

In a series of partial wiring patterns constituting the wiring pattern 13, test pads are provided on the partial wiring patterns which connect only surface mount components and are arranged only on the component surface 12a. I have. In the example of FIG. 2, the test pad 15 is provided on the partial wiring pattern 13a connected only between the surface mount components 21 and 22.

FIG. 3 is a partial sectional perspective view (FIGS. 3A and 3C) and a side sectional view (FIG. 3B) showing the structure of the test pad 15. As shown in FIG. The circuit board 11 is provided with a through hole 15 a penetrating the partial wiring pattern 13 a and the circuit board body 12. Inner side surface 15 of through hole 15a
B is plated with the same material as the wiring pattern 13. The component surface 12a and the back surface of the circuit board body 2,
That is, the through hole 15 is formed in the solder surface (second main surface) 12b.
In the opening a, circular patterns 15d and 15e having the same material as the wiring pattern 13 and having a predetermined diameter are provided, respectively. The plating 15c and the circular patterns 15d and 15e are conductors and are electrically connected to the partial wiring pattern 13a.

When the wiring pattern 13 is formed by using the printed wiring technique, the circuit board body 12 is formed before the wiring pattern 13 is formed.
Copper plating is applied in advance over the entire surface of the main surface.
A through hole 15 is provided in a predetermined position of the circuit board body 12 in advance.
By providing a, plating 15c during this copper plating,
And the circular patterns 15d and 15e can be formed simultaneously.

That is, the test pad 15 itself is
It has the same structure as a conventionally known through hole or via hole, and can be formed by the same method. However, the through holes are for the purpose of connecting discrete components, and the via holes are provided for the purpose of electrically connecting between the wiring patterns 13 provided on the two main surfaces of the circuit board body 12. It is something that can be done. The test pad 15 according to the present invention is not provided with any of them, but is provided on a partial wiring pattern 13a of the wiring pattern 13 which connects only surface mount components and is disposed only on the component surface 12a. At this position where the test pad 15 is provided, neither the through hole nor the via hole is provided. That is, it should be noted that the test pad 15 cannot be substituted for the through hole or the via hole. As described later, the test pad 15
The inspection of the mounted circuit board 20 can be executed with high efficiency and high accuracy.

Table 1 shows two typical examples of the dimensions of the test pad 15, that is, the outer diameters A, C and the inner diameter B of the circular patterns 15d, 15e. The one with a relatively small diameter is temporarily called a mini-buyer, and the one with a larger diameter is called a middle viar.

[0018]

[Table 1]

Needless to say, not only surface-mounted components but also discrete components may be mounted on the mounted circuit board 20.

<Method of Inspection> A method of inspecting the mounted circuit board 20 after forming the above-described mounted circuit board 20 will be described. 1 and 4 are explanatory diagrams showing this inspection method. The in-circuit tester (inspection device) 6 including the inspection pins 6a and 6b detects electrical characteristics such as resistance, capacitance, induction, impedance, and voltage between the inspection pins (probes) 6a and 6b in the device body 6c. I do.

In FIG. 1, all of the partial wiring patterns 13a connected to a pair of pins 22b of the surface mount component 22 are connected only to the other surface mount components and are arranged only on the component surface 12a. An example is shown. Therefore, test pads 15 are provided on these partial wiring patterns 13a. Whether the characteristics of the surface mount component 22 on the mount circuit board 20 are good or not,
Inspection of the connection between the wiring pattern 2 and the partial wiring pattern 13a is performed as follows.
The test is performed by pressing the test pins 6a and 6b against the two test pads 15 from the side of the solder surface 12b. In this inspection, if predetermined electrical characteristics inherent to the surface mount component 22 are detected, it is determined that both the surface mount component 22 itself and the connection between the surface mount component 22 and the partial wiring pattern 13a are good. Can be determined.
Conversely, if the predetermined electrical characteristics are not obtained, it can be determined that any of them is defective. In this case, the cause of the defect is further pursued by visual inspection, etc.
Predetermined measures such as replacement and repair are established.

FIG. 4 shows a method for inspecting the quality of the characteristics of the discrete component 23 on the mounting circuit board 20. The pin 23b is passed through a through hole of the through hole 16 connected to the wiring pattern 13, and the pin 23b
Are soldered to the through holes 16, so that the discrete components 23 are mounted at predetermined positions on the circuit board 11. Inspection of the discrete component 23 is performed by inserting the inspection pins 6a and 6b from the solder surface 12b side into the solder surface 1b.
This is executed by pressing against the tip of the pin 23b exposed to 2b.

FIG. 4 also shows a method of inspecting the surface mounted components 22 mounted on the mounted circuit board 20. In the surface mount component 22, one of the wiring patterns 13 connected to the pair of pins 22b is the other surface mount component 21.
And the other one is connected to a discrete component 23. The inspection pins 6a and 6b are connected to one pin 22b of the surface mount component 22 and the discrete component 23 connected to the other pin 22b by the wiring pattern 13.
By pressing the soldering surface 12b against one of the pins 23b from the side of the solder surface 12b, the inspection of the quality of the characteristics of the surface mounting component 22 and the inspection of the quality of the connection between the surface mounting component 22 and the wiring pattern 13 are executed. You.

As shown in the above example, in the inspection method of this embodiment, the inspection pins 6a and 6b are
5 or a pin exposed on the solder surface 12b of the discrete component from the side of the solder surface 12b, so that the surface mount component 21 on the mount circuit board 20;
Inspection is performed on 22 and the like and the connection state between them and the wiring pattern 13. There is no need to press the inspection pins 6a and 6b against the component surface 12a,
The inspection process is simpler and more efficient than the conventional method because it is only necessary to press against the side b. Also, unlike the conventional method, the inspection pins 6a,
6b, it is not necessary to press it, so that the inspection of the surface-mounted component 21 having a fine pitch can be easily performed. In addition, due to the pressure of the inspection pins 6a, 6b, the connection failure between the pin 21b and the wiring pattern 13 can be reduced. There is no fear of overlooking.

[0025]

According to the circuit board inspection method of the present invention, a test pad is provided on the circuit board in advance, and the probe of the inspection apparatus is brought into contact with the second main surface of the circuit board using the test pad. Then, an inspection of the mounted circuit board on which the surface mount type circuit component is mounted is executed. For this reason, it is not necessary to bring the probe into contact with both the first and second main surfaces, so that there is an effect that the inspection can be executed by a simple process. Also,
Since the probe does not need to be brought into contact with the surface-mounted circuit component, there is an effect that a high-precision inspection can be performed even in the inspection of a mounted circuit board on which a surface-mounted component having a fine pitch is mounted. Further, since the probe does not apply pressure to the surface mount component, there is an effect that a highly accurate inspection can be performed without failing to detect a defective connection between the surface mount component and the wiring pattern.

In the circuit board according to the present invention, the test pads are provided only in the wiring pattern portions connected only to the surface mount type components and provided only on the first main surface. Therefore, there is an effect that the inspection of the mounted circuit board formed by mounting the circuit component including the surface mounted component on the circuit board can be performed with a simple process and with high accuracy.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating an inspection method according to an embodiment of the present invention.

FIG. 2 is a structural diagram showing a structure of a mounted circuit board according to the embodiment of the present invention.

FIG. 3 is a structural diagram showing a structure of a test pad in the embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an inspection method according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram illustrating a conventional inspection method.

FIG. 6 is an explanatory diagram illustrating a conventional inspection method.

[Explanation of symbols]

 Reference Signs List 6 In-circuit tester 6a, 6b Inspection pin (probe) 11 Circuit board 12 Circuit board body 12a Component surface (first main surface) 12b Solder surface (second main surface) 13 Wiring pattern 15 Test pad 20 Mounting circuit board 21, 22 surface mount components (surface mount circuit components) 23 discrete components 21a, 22a, 23a main body

Claims (2)

(57) [Claims] 1. A circuit board inspection method for inspecting a mounted circuit board in which a plurality of circuit components including a plurality of surface-mounted circuit components are mounted on a circuit board, comprising: (a) first and second main components; Preparing a circuit board body of an electrical insulator having a surface; and (b) providing a pair of probes and contacting the object to be inspected.
A step of preparing an inspection device for inspecting the quality of the inspection object by detecting electrical characteristics between the pair of probes; and (c) electrically connecting the plurality of circuit components. Disposing a wiring pattern on at least the first main surface; and (d) disposing a test pad of an electric conductor substantially only on the first main surface in the wiring pattern. A part that is electrically connected to a part that connects only the plurality of surface-mounted circuit components, and that is mounted on the circuit board body such that a part of the part is exposed on the second main surface. (E) arranging the plurality of circuit components in a predetermined position on the circuit board main body such that each main body of the plurality of circuit components is positioned on the first main surface side of the circuit board main body. (C) forming a mounting circuit board by mounting at a position; The probe 1 of the pair is brought into contact with a portion of the test pad on the mounted circuit board exposed to the second main surface, and the other 1 is connected to the test pad of the other test pad on the mounted circuit board. 2 by contacting the portion of the circuit component on the mounting circuit board or the portion of the circuit component on the mounting circuit board that is exposed on the second main surface. Inspecting the quality of a portion to be electrically connected to the mold circuit component , wherein the step (d) comprises: (d-1) the portion of the wiring pattern and the circuit board;
Forming a through hole penetrating through the plate body; and (d-2) covering the inner surface on the inner surface of the through hole.
To form a member of the same material as the wiring pattern.
And extent, and said portion of said wiring pattern (d-3) the member
Is connected to, is made of the same material as Shikamoko these, the
An annular shape surrounding the opening of the through hole to the first main surface
Arranging a first circular pattern on the first main surface;
And degree, is connected to the (d-4) the member, yet the same as the member
An opening to the second main surface of the through hole, which is made of one material
To form an annular and isolated island surrounding the part
Disposing a circular pattern on the second main surface.
Circuit board inspection method Ru example. 2. A circuit board on which a plurality of circuit components including a plurality of surface mount circuit components are to be mounted, wherein: (a) a circuit board on which one main body of each of the plurality of circuit components is to be located; (B) a wiring pattern for electrically connecting the plurality of circuit components in a predetermined manner, the circuit pattern body including: a first main surface and a second main surface; At least the first
(C) a portion of the wiring pattern, which is provided only on the first main surface, and is provided only between the plurality of surface mount circuit components. A test pad electrically connected to a portion to be connected and installed on the circuit board main body, and a test pad substantially made of an electric conductor, a part of which is exposed on the second main surface; wherein the test pad, the circuit group and said portion of (c-1) the wiring pattern
A through hole penetrating through the plate body; and (c-2) an inner surface of the through hole covers the inner surface.
As described above, the wiring pattern is formed of the same material as that of the wiring pattern.
A member, and said portion of said wiring pattern (c-3) the member
And are made of the same material as those described above,
An annular shape surrounding the opening of the through hole to the first main surface
A first circular pattern disposed on the first main surface;
When connected to the (c-4) wherein member, yet the same as the member
The through-hole is opened to the second main surface.
In the shape of a circular and isolated island surrounding the mouth,
A second circuit board Ru with a circular pattern, a disposed on the second main surface.