JP2018160609A - Inspection circuit system and inspection method for mounting state of electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection circuit system and an inspection method that can determine the mounting state of an electronic device with a simple structure without time and expense.SOLUTION: An inspection circuit system includes only a part of a plurality of electrode pads and only a part of a plurality of lands, and the inspection circuit system includes at least two inspection circuits consisting of different series of paths separated from each other, and each of the inspection circuit includes an electronic component wiring that connects at least two of the plurality of electrode pads, a printed circuit board wiring that connects at least two of the plurality of lands, a conductive member disposed between an electrode pad located at an end portion of the electronic component wiring and a land located at an end portion of the printed circuit board wiring opposed to the electrode pad, conductive members located at both ends of the inspection circuit, and two inspection pads provided on the printed circuit board and respectively connected to both end portions of each of the inspection circuits.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inspection circuit system for mounting an electronic device. The present invention further relates to a method for inspecting the mounting state of an electronic device.

  In recent years, ICs such as LSIs use packages such as BGA (Ball Grid Array) and LGA (Land Grid Array), particularly in the case of large-sized ones. In the following description, BGA will be described as an example.

  The BGA is normally inspected by the BGA manufacturer. A board manufacturer that purchases such a BGA mounts it on a printed circuit board to construct an electronic device. However, the electronic device may not operate normally. The cause may be a defect in the BGA itself and a defect in the mounting state of the BGA on the printed circuit board. The latter defect in the mounting state is caused by a lack of flatness (coplanarity) of the BGA or warping of the printed circuit board. Possible contact failure between the solder ball and the printed circuit board.

  As a method for inspecting the mounting state of a BGA on a printed circuit board, for example, there is a method of observing a cross section of a solder ball using X-rays. However, this method is very time consuming and expensive, and eventually the cause may not be known. In addition, as a method for inspecting the mounting state of the BGA on the printed circuit board, there is also a method of simply inspecting from the side of the BGA by observation using a microscope or the like. However, this method makes it difficult to confirm the defect because other mounted parts around the BGA become obstacles.

Japanese Patent Laid-Open No. 11-87003 JP 2005-235854 A

  Each disclosure of the above prior art document is incorporated herein by reference. The following analysis is given by the present invention.

  In order to inspect the mounting state of the BGA on the printed circuit board, it has been proposed to form an inspection circuit system via the BGA and the printed circuit board and inspect the electrical conduction state.

  For example, Patent Document 1 basically connects two sets of solder pads 2a, 2b, 2c, and 2d at two opposite ends of a solder pad array of BGA 1 through internal wirings 3a and 3b, respectively. The connection pads 5b and 5d corresponding to the solder pads 2b and 2d, respectively, are connected by the internal wiring 6i in the mounting state of the connection pad array of the substrate 4, and the connection pads 5a and 5c corresponding to the solder pads 2a and 2c, respectively, in the mounting state. 5c is formed with the test lands 7a and 7c, respectively, and the electrical continuity between the test lands 7a and 7c is checked by a continuity checker or the like, so that the mounting state between the BGA 1 and the printed circuit board 4 is determined. Propose to inspect. However, this inspection circuit and inspection method cannot detect defects in the mounting state around the central portion of the BGA 1 or the printed circuit board 4. Furthermore, since this inspection circuit has a long wiring structure extending over three sides of the solder pad array or the connection pad array, the possibility of erroneous detection due to a defect in the wiring itself increases.

  Further, in Patent Document 2, basically, land terminals 3a and center land terminals 3b of the land terminal array of BGA 1 and land terminals 3 adjacent to these are connected by connection conductors 4, respectively. In the mounted state of the land terminal array, five independent probing terminals 5c and 5c ′ are drawn from the land terminals 3a and 5b of the BGA 1 and the land terminals 5a, 5b and 5 corresponding to the land terminals 3 adjacent thereto, respectively. It has been proposed to form an inspection circuit and inspect the electrical continuity between each pair of probing terminals. However, with this inspection circuit and inspection method, the mounting state can only be individually inspected at the four corners and the central portion. Further, Patent Document 2 provides the above-described inspection circuit with further probing terminals 5d ′ and 5d drawn from one of the corner terminals and one of the center land terminals, respectively, and electrical continuity therebetween. It also describes that the mounting states at the four corners and the central portion are inspected at a time by inspecting the state. However, in order to enable such an inspection, these land terminals 3a, 3b, 3, 5a, 5b, and 5 must all be connected in series, so that the printed circuit board 16 is long and complicated. A simple wiring structure (see the broken line in FIG. 2) must be formed.

  The present invention has been made in view of the above circumstances, and an inspection circuit system that makes it possible to determine the quality of the mounting state of an electronic device with a simple structure without spending time and money, and without spending time and money It is another object of the present invention to provide an inspection method that makes it possible to determine whether the electronic device is mounted properly. It is another object of the present invention to provide an electronic device capable of determining whether the mounting state is good without spending time and money.

According to a first aspect of the present invention, an electronic component having a plurality of electrode pads, a printed circuit board having a plurality of lands, and a plurality of electrodes for electrically connecting the plurality of electrode pads and the plurality of lands correspondingly. There is provided an inspection circuit system for inspecting the mounting state of an electronic device including a conductive member.
The inspection circuit system includes only a part of the plurality of electrode pads and only a part of the plurality of lands.
The inspection circuit system includes at least two inspection circuits consisting of a series of different paths separated from each other.
Each inspection circuit
In-electronic component wiring that connects between at least two of the plurality of electrode pads;
A printed circuit board wiring connecting between at least two of the plurality of lands;
A conductive member disposed between an electrode pad located at an end of the wiring in the electronic component and a land located at an end of the wiring in the printed circuit board opposed to the electrode pad;
And conductive members located at both ends of the inspection circuit.
The inspection circuit system further includes two inspection pads provided on the printed circuit board and connected to both ends of each inspection circuit.

According to a second aspect of the present invention, there is provided a method for inspecting a mounting state of an electronic device in which a plurality of electrode pads of an electronic component are connected to a plurality of lands of a printed circuit board through a conductive member.
The inspection method includes the following steps. That is,
A part of the plurality of electrode pads is connected by wiring in an electronic component, a part of the plurality of lands is connected by wiring in a printed circuit board, and the electronic component is mounted on the printed circuit board. A plurality of inspection circuits comprising a series of different paths separated from each other are formed by the wiring in the printed circuit board and a part of the plurality of lands and the part of the electronic component wiring and the plurality of electrode pads.
Two inspection pads respectively connected to both ends of each inspection circuit are provided on the printed circuit board.
Measuring a resistance value between the two test pads of each test circuit;

  According to a third aspect of the present invention, there is provided an electronic device including the inspection circuit system according to the first aspect (or modes 1 to 7).

  According to the fourth aspect of the present invention, a program for carrying out the inspection method according to the second viewpoint is provided.

  According to the first aspect of the present invention, it is possible to provide an inspection circuit system that can determine whether or not an electronic device is mounted with a simple structure without spending time and money. According to the second aspect of the present invention, it is possible to provide an inspection method that makes it possible to determine whether the electronic device is mounted or not without spending time and money. According to the third aspect of the present invention, it is possible to provide an electronic device that can determine whether or not the mounting state is good without spending time and money.

1 is a schematic perspective view of an electronic device including an inspection circuit system according to an embodiment of the present invention as viewed from the back surface of a printed board. It is arrow XX sectional drawing of the test | inspection circuit system of FIG. 1, Comprising: It represents the state without a contact failure of solder. It is arrow XX sectional drawing of the test | inspection circuit system of FIG. 1, Comprising: It represents the state with a contact failure of solder in the peripheral part of IC. It is arrow XX sectional drawing of the test | inspection circuit system of FIG. 1, Comprising: The state with a contact failure of solder in the center part of IC is represented. An example of an inspection circuit system when the internal connection of an IC cannot be changed. An example of the program for performing the inspection method of the mounting state of the electronic device by one Embodiment of this invention.

  The outline of the present invention will be described with reference to FIGS. It should be noted that the reference numerals of the drawings attached to the outline are only for the purpose of assisting understanding, and are not intended to limit the present invention to the illustrated embodiment.

  An electronic device including an inspection circuit system according to the present invention is arranged in an array corresponding to an electronic component (such as an IC) 12 having a plurality of electrode pads 15 arranged in an array and the plurality of electrode pads 15. In addition, the printed circuit board 14 having the plurality of lands 16 and the plurality of conductive elements arranged in the same array for electrically connecting the corresponding electrode pads 15 and the lands 16 in the mounted state of the electronic component 12 and the printed circuit board 14. It is comprised including the property member (solder ball etc.) 13. In the following example, an array (or matrix) of these electrode pads 15, lands 16 and conductive members 13 is assumed to be a 5 × 5 array, and the positions of the elements of the array are denoted by reference signs A to E, 1 To 5 (see FIG. 1). For example, the electrode pad 15, the land 16, and the conductive member 13 located at A1 in FIG. 1 are represented by 15A1, 16A1, and 13A1, respectively. Further, for example, the wiring in the electronic component that connects the electrode pads 15A1 and 15B2 in FIG. 1 is represented by A1B2, and similarly, the wiring in the printed board that connects the lands 16B2 and 16D4 is represented by B2D4. In the example of FIG. 1, a 5 × 5 array is assumed, but the number of rows and columns of the array can take values corresponding to actual products.

  The inspection circuit system according to the present invention includes only a part of the plurality of electrode pads 15 and only a part of the plurality of lands 16. For example, in the example of FIG. 1, the inspection circuit system includes eight electrode pads 15A1, 15B2, 15D4, 15E5, 15A5, 15B4, 15D2, and 15E1 out of 24 electrode pads 15 and 24 lands 16. Of these, only eight lands 16A1, 16B2, 16D4, 16E5, 16A5, 16B4, 16D2, and 16E1 are included.

  Furthermore, the inspection circuit system according to the present invention includes at least two inspection circuits having different paths separated from each other. For example, in the example of FIG. 1, the test circuit system includes two test circuits: a first test circuit consisting of a path passing through array positions A1, B2, D4 and E5, and an array position A5, B4, D2. And a second inspection circuit comprising a path passing through E1.

  Furthermore, in the inspection circuit system according to the present invention, each inspection circuit is provided between the wiring in the electronic component that connects at least two of the plurality of electrode pads 15 and at least two of the plurality of lands 16. In-printed circuit board wiring is included. For example, in the example of FIG. 1, the first inspection circuit connects the wirings A1B2 and D4E5 (broken lines in FIG. 1) connecting the electrode pads 15A1 and 15B2 and 15D4 and 15E5 to the lands 16B2 and 16D4. The printed circuit board wiring B2D4 (solid line in FIG. 1), the second inspection circuit includes wirings A5B4 and D2E1 (broken lines in FIG. 1) connecting the electrode pads 15A5 and 15B4 and 15D2 and 15E1, and 16B4 It includes printed circuit board wiring B4D2 (solid line in FIG. 1) for connecting 16D2 lands. In the example of FIG. 1, the wirings in the electronic components of the first inspection circuit and the second inspection circuit both have two spatially separated parts, that is, A1B2 and D4E5 (first inspection circuit) and A5B4 and D2E1. (Second inspection circuit).

  Furthermore, in the inspection circuit system according to the present invention, each inspection circuit includes an electrode pad located at the end of the wiring in the electronic component and a land located at the end of the wiring in the printed circuit board disposed opposite to the electrode pad. Including a conductive member disposed therebetween. For example, in the example of FIG. 1, the wiring in the electronic component of the first inspection circuit is formed from two wiring portions that are spatially separated, that is, A1B2 and D4E5, but is located at two ends of these wiring portions. Electrode pads 15B2 and 15D4, and conductive members 13B2 and 13D4 disposed between lands 16B2 and 16D4 located at the ends of the printed circuit board wirings arranged to face these ends, respectively. The same applies to the second inspection circuit.

  Furthermore, in the inspection circuit system according to the present invention, each inspection circuit includes conductive members located at both ends of the inspection circuit. For example, in the example of FIG. 1, the first inspection circuit includes conductive members 13A1 and 13E5 located at both ends A1 and E5, and the second inspection circuit is a conductive member located at both ends A5 and E1, respectively. Including 13A5 and 13E1.

  Furthermore, the inspection circuit system according to the present invention includes two inspection pads provided on the printed circuit board 14 and connected to both ends of each inspection circuit. For example, in the example of FIG. 1, the inspection circuit system includes two inspection pads 17 and 17 provided on the printed board 14 and connected to both ends A1 and E5 of the first inspection circuit, respectively. And two test pads 18 and 18 respectively connected to both ends A5 and E1 of the second test circuit.

  In an electronic apparatus including such an inspection circuit system, for example, when the mounting state is benign as shown in FIG. 2, the resistance value between the inspection pads 17 and 17 and between the inspection pads 18 and 18. To get the expected value. On the other hand, for example, when there is a defect in the mounting state as shown in FIG. 3 or FIG. 4, when the resistance value is measured between the test pads 17 and 17 and between the test pads 18 and 18, at least On the other hand, the resistance value greatly exceeds the expected value (theoretically infinite). The desired value of the resistance value is a value in a certain range that is theoretically obtained from the characteristics of the circuit. In this embodiment, the resistance value is used as a parameter for inspecting the electrical continuity state of the inspection circuit. However, the present invention is not limited to this, and any parameter that can inspect the electrical continuity state of the inspection circuit is used. Anything can be used.

  By using an inspection circuit system having an extremely simple structure as described above, it is possible to determine whether or not the electronic device is mounted as a product to be shipped as a product without taking time and money.

  In the perspective view seen from the back side of FIG. 1 printed circuit board, the first inspection circuit and the second inspection circuit appear to be connected at the center of the array. However, the printed circuit board wiring B2D4 of the first inspection circuit and the printed circuit board wiring B4D2 of the second inspection circuit are arranged in different wiring layers of the printed circuit board 14, and therefore the first inspection circuit and the second inspection circuit are They are separated from each other spatially and electrically.

  According to a further aspect of the present invention, in the inspection circuit system, at least two inspection circuits are in an arbitrary shape with respect to the joint surface of the electronic component 12 (or the printed circuit board 14), more precisely in the projection view on the joint surface. Can be formed, for example, in a stepped manner, but is preferably formed linearly.

  According to a further aspect of the present invention, in the inspection circuit system, at least two inspection circuits are related to the bonding surface of the electronic component 12 (or the printed circuit board 14), more precisely in the projection view on the bonding surface, respectively. It can be oriented in a direction, for example parallel to each other, but advantageously any two of the at least two test circuits are oriented in crossing directions. Note that the intersecting direction means non-parallel, and is not necessarily limited to the one intersecting within the region of the array in the projection onto the joint surface as shown in FIG.

  In a further aspect of the present invention, in the inspection circuit system, the bonding surface of the electronic component 12 (or the printed circuit board 14) is related, and more precisely in the projection view on the bonding surface, at least two inspection circuits are the electronic component 12 or Although it can be formed to pass through any location on the printed circuit board 14, advantageously at least one of the at least two inspection circuits is formed to pass through the electronic component 12 or the central portion of the printed circuit board 14.

  In a further form of the invention, in an inspection circuit system, at least two inspection circuits are particularly advantageous in relation to the joint surface of the electronic component 12 (or printed circuit board 14), more precisely in a projection view on the joint surface. These are two test circuits formed on the diagonal of the array of electronic components 12 or printed circuit board 14 as described for example in FIG. This inspection system can inspect the mounting state over the entire surface of the electronic device with an inspection circuit having the smallest and simplest structure.

  In a further aspect of the present invention, in the inspection circuit system, the electronic component internal wiring included in at least one of the at least two inspection circuits is preferably formed from at least two parts that are spatially separated. In the example of the 5 × 5 array shown in FIG. 1, the first inspection circuit has an electronic component internal wiring composed of two parts A1B2 and D4E5 that are spatially separated, and the two parts A1B2 of the electronic component internal wiring. And the second inspection circuit is formed of two parts A5B4 and D2E1 that are spatially separated from each other, and the electronic component internal wiring, and the electronic component internal wiring. Although formed from the printed circuit board wiring B4D2 arranged between the two portions A5B4 and D2E1, it is not limited to this form. In the present invention, in the inspection circuit, the wiring part in the electronic component and the wiring part in the printed circuit board are alternately arranged, that is, the inspection circuit is formed so as to “sewn” the electronic component and the printed circuit board. In addition, according to the increase in the number of rows and columns of the array, the wiring in the electronic component of the inspection circuit is composed of three or more parts spatially separated, and the wiring in the printed circuit board of the inspection circuit It is also possible to construct two or more parts separated from each other.

  Specific embodiments of the present invention will be described below in detail with reference to the drawings. Note that the reference numerals of the drawings attached to the following embodiments are only for helping understanding, and are not intended to limit the present invention to the illustrated embodiments.

  FIG. 1 is a schematic perspective view of an electronic device including an inspection circuit system according to an embodiment of the present invention viewed from the back surface of a printed circuit board 14. The illustrated electronic device includes an IC (electronic component) 12 having 24 electrode pads 15 (see FIG. 2) arranged in a 5 × 5 array on its lower surface or bonding surface, and the plurality of electrode pads. Printed circuit board 14 having 24 lands 16 (see FIG. 2) arranged in a 5 × 5 array corresponding to 15 on its upper surface or bonding surface, and corresponding electrodes in the mounted state of IC 12 and printed circuit board 14 Similarly, it includes 24 solder balls (conductive members) 13 arranged in a 5 × 5 array for electrically connecting the pad 15 and the land 16.

  The illustrated inspection circuit system includes two inspection circuits each having a different series of paths. Specifically, it is composed of a first inspection circuit that passes through A1, B2, D4, and E5 of the array, and a second inspection circuit that passes through A5, B4, D2, and E1 of the array. The second test circuit extends linearly through the central portion of the array on the different diagonals of the array and thus in a direction intersecting each other in the perspective view of FIG.

  In the first inspection circuit, the land 16A1 and the electrode pad 15A1 are connected via the solder ball 13A1, the electrode pad 15A1 and the electrode pad 15B2 are connected by the electronic component internal wiring A1B2, and the electrode pad 15B2 and the land 16B2 connect the solder ball 13B2. The land 16B2 and the land 16D4 are connected by the printed circuit board wiring B2D4, the land 16D4 and the electrode pad 15D4 are connected by the solder ball 13D4, and the electrode pad 15D4 and the electrode pad 15E5 are connected by the electronic component wiring D4E5. This is a series circuit in which electrode pads 15E5 and lands 16E5 are connected via solder balls 13E5. In the second inspection circuit, the land 16A5 and the electrode pad 15A5 are connected via the solder ball 13A5, the electrode pad 15A5 and the electrode pad 15B4 are connected by the electronic component internal wiring A5B4, and the electrode pad 15B4 and the land 16B4 are the solder ball. 13B4, the land 16B4 and the land 16D2 are connected via the printed circuit board wiring B4D2, the land 16D2 and the electrode pad 15D2 are connected via the solder ball 13D2, and the electrode pad 15D2 and the electrode pad 15E1 are connected to the electronic component wiring. This is a series circuit in which the electrode pad 15E1 and the land 16E1 are connected via the solder ball 13E1 and connected by D2E1. In FIG. 1, the wiring in the electronic component is indicated by a broken line, and the wiring in the printed board is indicated by a solid line.

  The printed circuit board wiring B2D4 of the first inspection circuit and the printed circuit board wiring B4D2 of the second inspection circuit are arranged in different wiring layers of the printed circuit board 14, and therefore the first inspection circuit and the second inspection circuit are spatially separated. And electrically separated from each other.

  The inspection circuit system further includes two inspection pads 17 and 17 connected to lands 16A1 and 16E5 at both ends of the first inspection circuit, and lands 16A5 at both ends of the second inspection circuit. And two test pads 18, 18 connected to 16E1, respectively. Thus, it is possible to test the electrical continuity between the two test pads 17 and 17 of the first test circuit and between the two test pads 18 and 18 of the second test circuit.

  FIG. 2 is a cross-sectional view taken along the line XX in FIG. 1 and shows a state where there is no poor contact of solder, that is, a state where the electronic device is not defective. In this case, in the first test circuit, the illustrated path abcdchefgh is electrically connected properly, so that the resistance between the two test pads 17 and 17 is the same. When the value is measured by the tester 11, the desired resistance value is obtained. Further, the same measurement is performed in a second inspection circuit (not shown), and if an expected resistance value is obtained, there is no problem in the mounting state of the electronic device when an error is detected by the inspection of the electronic device. Therefore, it can be easily determined that there is a problem with the IC itself.

  3 and 4 are cross-sectional views taken along the line XX of FIG. 1, and there is a defect in the state where there is a poor contact of solder due to lack of flatness of the IC 12 and / or the printed circuit board 14, that is, the mounting state of the electronic device. Indicates a certain state. In FIGS. 3 and 4, the electrode pads and lands are omitted from the viewpoint of easy viewing.

  FIG. 3 shows a state in which the solder ball 13 floats around the periphery of the IC 12. In this case, in the first inspection circuit, the connection between ab and gh among the illustrated paths abc-d-e-f-g-h is electrically disconnected. When the resistance value between the two test pads 17 and 17 is measured by the tester 11, a resistance value that is very large (theoretically infinite) compared to the intended resistance value is obtained (for example, test). The resistance value of the largest value in the displayable range is displayed on the device 11). Furthermore, additionally or alternatively, the same measurement can be performed in a second test circuit (not shown), and an abnormally large resistance value can be obtained in either the first test circuit or the second test circuit. For example, when an error is detected by inspection of the electronic device, it can be easily determined that the cause is at least a defect in the mounting state of the electronic device.

  FIG. 4 shows a state in which the solder ball 13 floats at the center of the IC 12. In this case, in the first inspection circuit, the connection between cd and ef among the paths ab-c-d-e-f-g-h shown in FIG. When the resistance value between the two test pads 17 and 17 is measured by the tester 11, a very large resistance value can be obtained as compared with the intended resistance value. Furthermore, additionally or alternatively, the same measurement can be performed in a second test circuit (not shown), and an abnormally large resistance value can be obtained in either the first test circuit or the second test circuit. For example, when an error is detected by inspection of the electronic device, it can be easily determined that the cause is at least a defect in the mounting state of the electronic device.

  The example shown in FIG. 1 is based on the premise that the connection in the IC can be arbitrarily set or changed, but there are also cases where the connection in the IC cannot be arbitrarily set or changed as in, for example, a product of another company. An example of the inspection circuit system of the present invention applied to such a case is shown in FIG. In this example, the combination of the electrode pads B3, B4, and B5 of the IC and the combination of C2 and D2 are connected to each other by an internal wiring (broken line) so as not to be changed. In this case, for example, a land B3 connected to the electrode pad B3 via the solder ball B3 and a land A3 adjacent to the land B3 are connected via the printed circuit board wiring B3A3 and connected to the electrode pad B5 via the solder ball B5. A first detection circuit is configured by connecting the adjacent land A5 with the printed circuit board wiring B5A5, and the land C2 connected to the electrode pad C2 via the solder ball C2 and the adjacent land C1 are connected to the printed circuit board wiring C2C1. The second detection circuit is configured by connecting the land D2 connected to the electrode pad D2 via the solder ball D2 and the land E2 adjacent to the land D2 with the wiring D2E2 in the printed circuit board. Two test pads 27 and 27 connected to lands A3 and A5 at both ends of the first test circuit, respectively, and a second test circuit By providing two test pads 28 and 28 which are respectively connected to the lands C1 and E2 at both ends, it is possible to configure the inspection circuit system. Although the illustrated inspection circuit system is also partial, the mounting state of the electronic device can be easily and quickly inspected.

In the following, preferred forms relating to the present invention disclosed in the present specification and drawings are appended.
[Form 1]
An electronic device comprising: an electronic component having a plurality of electrode pads; a printed circuit board having a plurality of lands; and a plurality of conductive members for electrically connecting the plurality of electrode pads to the plurality of lands. An inspection circuit system for inspecting the mounting state of
The inspection circuit system includes only a part of the plurality of electrode pads and only a part of the plurality of lands.
The test circuit system includes at least two test circuits consisting of different series of paths separated from each other,
Each inspection circuit
In-electronic component wiring that connects between at least two of the plurality of electrode pads;
A printed circuit board wiring connecting between at least two of the plurality of lands;
A conductive member disposed between an electrode pad located at an end of the wiring in the electronic component and a land located at an end of the wiring in the printed circuit board opposed to the electrode pad;
And conductive members located at both ends of the inspection circuit,
The inspection circuit system further includes two inspection pads provided on the printed circuit board and connected to both ends of each inspection circuit, respectively.
Inspection circuit system.
[Form 2]
The at least two inspection circuits are linearly formed with respect to a joint surface of the electronic component;
The inspection circuit system according to the first aspect.
[Form 3]
Any two of the at least two inspection circuits are formed so as to be oriented in a direction intersecting with respect to a joint surface of the electronic component.
The inspection circuit system according to the first or second aspect.
[Form 4]
At least one of the at least two inspection circuits is formed so as to pass through a central portion with respect to a joint surface of the electronic component.
4. The inspection circuit system according to any one of forms 1 to 3.
[Form 5]
The at least two inspection circuits are two inspection circuits formed in a diagonal direction of a joint surface of the electronic component.
5. The inspection circuit system according to any one of forms 1 to 4.
[Form 6]
Electronic component internal wiring included in at least one of the at least two inspection circuits is formed of at least two portions that are spatially separated.
6. The inspection circuit system according to any one of forms 1 to 5.
[Form 7]
Each inspection circuit is formed from an electronic component internal wiring composed of two spatially separated parts and a printed circuit board internal wiring arranged between the two parts of the electronic component internal wiring.
7. The inspection circuit system according to any one of forms 1 to 6.
[Form 8]
A method for inspecting a mounting state of an electronic device in which a plurality of electrode pads of an electronic component are connected to a plurality of lands of a printed circuit board through a conductive member,
A part of the plurality of electrode pads is connected by wiring in an electronic component, a part of the plurality of lands is connected by wiring in a printed circuit board, and the electronic component is mounted on the printed circuit board. A plurality of inspection circuits comprising a series of different paths separated from each other by a part of the printed circuit board wiring and the plurality of lands and the electronic component wiring and the plurality of electrode pads,
Two test pads connected to both ends of each test circuit are provided on the printed circuit board,
Measuring a resistance value between the two test pads of each test circuit;
Inspection method.
[Form 9]
The at least two inspection circuits are two wiring patterns formed diagonally with respect to the joint surface of the electronic component.
The inspection method according to aspect 8.
[Mode 10]
When the resistance values for all of the at least two inspection circuits are within the expected value range, it is determined that there is no problem in the mounting state of the electronic device.
The inspection method according to Form 8 or 9.
[Form 11]
When at least one resistance value of the at least two inspection circuits is outside the range of an expected value, it is determined that the mounting state of the electronic device is defective.
The inspection method according to Form 8 or 9.
[Form 12]
An electronic device including the inspection circuit system according to any one of forms 1 to 7.
[Form 13]
A program for carrying out the inspection method according to any one of forms 8 to 11.
[Form 14]
8. A method for inspecting a mounting state of an electronic device, wherein resistance values are measured for the at least two inspection circuits of the inspection circuit system according to any one of forms 1 to 7.
[Form 15]
When the resistance values for all of the at least two inspection circuits are within the expected value range, it is determined that there is no problem in the mounting state of the electronic device.
The inspection method according to Form 14.
[Form 16]
When at least one resistance value of the at least two inspection circuits is outside the range of an expected value, it is determined that the mounting state of the electronic device is defective.
The inspection method according to Form 14.
[Form 17]
A program for performing the inspection method according to any one of Forms 14 to 16.

  Each disclosure of the cited patent documents and the like cited above is incorporated herein by reference. Within the scope of the entire disclosure (including claims and drawings) of the present invention, the embodiments can be changed and adjusted based on the basic technical concept. Various combinations and selections of various disclosed elements (including each element of each claim, each element of each embodiment, each element of each drawing, etc.) are possible within the scope of the claims of the present invention. is there. That is, the present invention naturally includes various modifications and changes that could be made by those skilled in the art according to the entire disclosure including the claims and the drawings, and the technical idea.

11 Inspection device 12 IC (electronic parts)
13 Solder balls (conductive members)
14 Printed Circuit Board 15 Electrode Pad 16 Land 17 Inspection Pad for First Inspection Circuit 18 Inspection Pad for Second Inspection Circuit 23 Solder Ball (Conductive Member)
24 Printed Circuit Board 27 Inspection Pad for First Inspection Circuit 28 Inspection Pad for Second Inspection Circuit

Claims (10)

An electronic device comprising: an electronic component having a plurality of electrode pads; a printed circuit board having a plurality of lands; and a plurality of conductive members for electrically connecting the plurality of electrode pads to the plurality of lands. An inspection circuit system for inspecting the mounting state of
The inspection circuit system includes only a part of the plurality of electrode pads and only a part of the plurality of lands.
The test circuit system includes at least two test circuits consisting of different series of paths separated from each other,
Each inspection circuit
In-electronic component wiring that connects between at least two of the plurality of electrode pads;
A printed circuit board wiring connecting between at least two of the plurality of lands;
A conductive member disposed between an electrode pad located at an end of the wiring in the electronic component and a land located at an end of the wiring in the printed circuit board opposed to the electrode pad;
And conductive members located at both ends of the inspection circuit,
The inspection circuit system further includes two inspection pads provided on the printed circuit board and connected to both ends of each inspection circuit, respectively.
Inspection circuit system. The at least two inspection circuits are linearly formed with respect to a joint surface of the electronic component;
The inspection circuit system according to claim 1. Any two of the at least two inspection circuits are formed so as to be oriented in a direction intersecting with respect to a joint surface of the electronic component.
The inspection circuit system according to claim 1 or 2. At least one of the at least two inspection circuits is formed so as to pass through a central portion with respect to a joint surface of the electronic component.
The inspection circuit system according to claim 1. The at least two inspection circuits are two inspection circuits formed in a diagonal direction of a joint surface of the electronic component.
The inspection circuit system according to claim 1. Electronic component internal wiring included in at least one of the at least two inspection circuits is formed of at least two portions that are spatially separated.
The inspection circuit system according to claim 1. Each inspection circuit is formed from an electronic component internal wiring composed of two spatially separated parts and a printed circuit board internal wiring arranged between the two parts of the electronic component internal wiring.
The inspection circuit system according to claim 1. A method for inspecting a mounting state of an electronic device in which a plurality of electrode pads of an electronic component are connected to a plurality of lands of a printed circuit board through a conductive member,
A part of the plurality of electrode pads is connected by wiring in an electronic component, a part of the plurality of lands is connected by wiring in a printed circuit board, and the electronic component is mounted on the printed circuit board. A plurality of inspection circuits comprising a series of different paths separated from each other by a part of the printed circuit board wiring and the plurality of lands and the electronic component wiring and the plurality of electrode pads,
Two test pads connected to both ends of each test circuit are provided on the printed circuit board,
Measuring a resistance value between the two test pads of each test circuit;
Inspection method. The plurality of inspection circuits are two wiring patterns formed in a diagonal direction with respect to the joint surface of the electronic component.
The inspection method according to claim 8.   An electronic device comprising the inspection circuit system according to claim 1.

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