JP2008060162A - Mount testing apparatus for testing appropriate design of land pattern, and its mount testing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mount testing apparatus by which the propriety of land pattern design formed on a printed wiring board can be tested for a short time, and to provide its mount testing method. <P>SOLUTION: The mount testing apparatus 7 is provided with a printed wiring board 1 for mount testing wherein a specified measuring pad 23 is connected with a specified terminal land 21 and a land pattern 20 is formed that the specified terminal lands 21 are connected with each other, a mount testing imitation electronic part 2 by shortcircuiting specified terminals 11, a continuity detection means 3 connected between the specified terminal lands 21 and 21, and a power supply means 75 to be connected with the measuring pads 23. When mounting the mount testing imitation electronic part 1 to a printed wiring board 1 for mount testing, the terminal land 21 and the connection terminal 11 are used to form a series circuit wherein one of the measuring pads 23 is a starting point and the other thereof is an end point, thus judging whether or not the design of the land pattern 20 is appropriate according to the state of current running in the continuity detection means 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a mounting test apparatus and a mounting test method for testing suitability of design of a land pattern formed on a printed wiring board.

  In a printed wiring board, a land pattern for mounting an electronic component having a plurality of connection terminals such as an IC (Integrated Circuit) is designed according to the shape of the IC body, the arrangement of the connection terminals, or the tip shape thereof. Specifically, the terminal lands constituting the land pattern are arranged corresponding to the shape of the IC body and the arrangement of the connection terminals, and the shape of the terminal lands is the tip shape of the connection terminals that contact the terminal lands. Based on this, it is designed to be slightly larger than the tip shape of the connection terminal.

  However, even if the terminal lands are designed according to the design rules according to the shape of the IC body, the arrangement of the connection terminals, and the tip shape thereof, a pattern with unreliability may be produced in actual use. For example, when the size of the terminal land is not sufficient with respect to the size of the connection terminal of the IC, when other components are mounted and an impact is applied to the printed wiring board, or when the printed wiring board is deformed, Insufficient solder joint strength between the connection terminal and the terminal land may occur. When such a situation occurs, the connection terminal may be peeled off from the terminal land.

  For this reason, after the land pattern design, the designed land pattern is formed on the printed wiring board, the IC is mounted on the land pattern, and the printed wiring board on which the IC is mounted is deformed by applying a load, thereby connecting terminals. And whether the designed land pattern can withstand the reliability test, and judge the suitability of the land pattern design. Yes. And when peeling arises, correction, such as enlarging the size of the terminal land of the location, is performed, and it is set as a more reliable land pattern.

  As a method for inspecting whether or not the land pattern of the printed wiring board is peeled off, there is a method for visually inspecting the presence or absence of peeling at the connection portion between the connection terminal and the terminal land. In this method, an IC is mounted on a printed circuit board on which a designed land pattern is formed, a load is applied, a deformation test is performed, and then the joint is enlarged with a microscope or the like between the connection terminal and the terminal land. Whether or not peeling has occurred is visually inspected.

  As another method, a method of electrically measuring the connection state between the connection terminal and the terminal land and inspecting the presence or absence of peeling at the connection portion between the connection terminal and the terminal land can be considered. For example, it is conceivable to apply the method described in Patent Document 1. The method described in Patent Document 1 checks whether or not the mounting state of the electronic component is appropriate. For example, the arrangement direction of the electronic component, whether the planned electronic component is mounted, or the like. This method can be applied to the inspection of the connection state between the connection terminal and the terminal land. Below, the example which applied the method described in patent document 1 to the test | inspection of the presence or absence of peeling in the junction part of a connection terminal and a terminal land is demonstrated.

  FIG. 6 is an explanatory diagram for explaining a method of inspecting a land pattern by applying a conventional method.

  In this method, in the IC 102 mounted on the printed wiring board 101, a specific pair of connection terminals 111, 111 are short-circuited in advance by the connection line 112 inside the IC body. When the IC 102 is mounted on the printed wiring board 101, the tester 105 or the like inspects the energization state between the pair of terminal lands 121 and 121 connected to the pair of shorted connection terminals 111 and 111.

  When there is no separation between the connection terminal 111 and the terminal land 121, the pair of terminal lands 121 and 121 are connected to each other via the pair of connection terminals 111 and 111. On the other hand, when the state is detected and peeling occurs between the connection terminal 111 and the terminal land 121, the open state is detected.

Therefore, it is possible to inspect whether or not peeling occurs between the connection terminal 111 and the terminal land 121 by such a method.
JP-A-2-147869

  However, the visual method is such that, when mounted on a printed wiring board, such as a SOP (Small Outline Package) package or a QFP (Quad Flat Package) package, the joint between the connection terminal and the terminal land appears on the surface of the substrate. It can be applied to those where the joint can be visually observed, but it is applicable to those where the connection terminal is hidden under the IC body, such as a BGA (Ball Grid Array) package or QFN (Quad Flat Non-Leaded Package). Difficult to do.

  Further, since the peeling between the connection terminals and the terminal lands is difficult to visually confirm, it is necessary to inspect a plurality of connection terminals one by one, and there is a problem that it takes an inspection time. As a result, the suitability of the land pattern design could not be determined in a short time.

  In addition, the method as disclosed in Patent Document 1 has a problem that only peeling between a specific pair of connection terminals and a pair of terminal lands bonded to the connection terminals can be inspected. Even if such a method is applied to all other connection terminals, in an IC having a plurality of connection terminals, it is necessary to repeat the inspection of the energized state for each connection terminal pair by a tester. There was a problem that it took. As a result, the suitability of the land pattern design could not be determined in a short time.

  The present invention has been made in view of such a situation, and provides a mounting test apparatus and a mounting test method for testing the suitability of the design of a land pattern formed on a printed wiring board in a short time. For the purpose.

  A mounting test apparatus according to the present invention is a mounting test apparatus for testing the suitability of the design of a land pattern formed on a printed wiring board corresponding to an electronic component to be mounted, and includes at least two measurement pads. And a land pattern according to the design is formed, and the terminal land constituting the land pattern is a pad connection group consisting of terminal lands connected to each of the measurement pads in a one-to-one manner, and other than this pad connection group A printed circuit board for mounting test divided into one or a plurality of pair connection groups in which two terminal lands are connected to each other as a set, and connection imitating electronic components to be mounted Among these connection terminals, the connection terminals corresponding to the adjacent terminal lands that are not mutually connected in the terminal lands are provided. A mounting test simulated electronic component, an energization detecting means connected between adjacent terminal lands not connected to each other in the terminal lands, and the measurement pads of the mounting test printed wiring board; Power supply means to be connected, and when the mounting test simulated electronic component is mounted on the mounting test printed wiring board, the terminal land of the mounting test printed wiring board and the mounting test simulated electronic component One or a plurality of series circuits starting from one of the measurement pads and ending at the other are constituted by the connection terminals, and whether or not the land pattern is properly designed depending on the state of the current flowing through the energization detecting means. Is determined.

  According to the present invention, when the mounting test simulated electronic component is mounted on the mounting test printed wiring board, the measurement pad of the mounting test printed wiring board and the connection terminal of the mounting test simulated electronic component One or a plurality of series circuits starting from one and ending at the other are configured, and a current is passed through the series circuit, while a current detection means is connected between adjacent terminal lands that are not connected to each other at the terminal lands. Since the energization state between the terminal lands is detected, it is possible to detect whether or not peeling or poor connection has occurred in the connection state between the connection terminal and the terminal land at approximately the same time. The suitability of the land pattern design can be determined in a short time.

  In addition, since the connection state between the connection terminal and the terminal land is detected by the energization detection means, even if the joint between the connection terminal and the terminal land cannot be visually observed due to the package structure of the electronic component, The connection state with the terminal land can be grasped.

  In the mounting test apparatus according to the present invention, the energization detecting means may include a light emitting device that emits light when a change in energized state is detected.

  With this configuration, when a change in the energization state is detected by the energization detection means, the energization detection means emits light, so that the location where the energization state has changed can be identified by visual inspection, and the occurrence of peeling or poor connection can be identified. It can be grasped instantly. Therefore, the test operator can easily determine whether or not the land pattern design is appropriate.

  A mounting test method according to the present invention is a mounting test method for testing the suitability of the design of a land pattern formed on a printed wiring board corresponding to an electronic component to be mounted, and includes at least two measurement pads. And a land pattern according to the design is formed, and the terminal land constituting the land pattern is a pad connection group consisting of terminal lands connected to each of the measurement pads in a one-to-one manner, and other than this pad connection group The printed circuit board for mounting test is divided into one or a plurality of pair connection groups, each of which is connected to each other as a set of two terminal lands. The connection terminals corresponding to the adjacent terminal lands that are not connected to each other in the terminal lands are provided. Forming a simulated electronic component for mounting test in which terminals are short-circuited, and mounting the simulated electronic component for mounting test on the printed wiring board for mounting test and the terminal land of the printed wiring board for mounting test and the The energization detecting means for detecting one or more series circuits starting from one of the measurement pads and ending at the other by the connection terminal of the simulated electronic component for mounting test, A state of current flowing through the current detection means by supplying power from the power supply means to the series circuit via the measurement pads in a state of being connected between the adjacent terminal lands that are not connected to each other in the terminal lands. In this case, the suitability of the land pattern design is determined.

  According to the present invention, by mounting the mounting test simulated electronic component on the mounting test printed wiring board, and connecting the terminal land of the mounting test printed wiring board and the connection terminal of the mounting test simulated electronic component, the measurement is performed. Configure one or more series circuits with one of the pads as the starting point and the other as the ending point, and passing current through the series circuit, while detecting the energization between adjacent terminal lands that are not connected to each other in the terminal lands By connecting the means and detecting the energization state between the terminal lands, it is possible to detect whether or not peeling or poor connection has occurred in the connection state between the connection terminals and the terminal lands at approximately the same time. As a result, the suitability of the land pattern design can be determined in a short time.

  In addition, since the connection state between the connection terminal and the terminal land is detected by the energization detection means, even if the joint between the connection terminal and the terminal land cannot be visually observed due to the package structure of the electronic component, The connection state with the terminal land can be grasped.

  In the mounting test method according to the present invention, the mounting test printed wiring board may be subjected to a bending stress.

  With this configuration, it is possible to obtain a bending stress value at which peeling or connection failure occurs because the peeling or connection failure occurring at the connection terminal and the terminal land is detected while bending stress is applied to the printed wiring board for mounting test. Therefore, the suitability of the designed land pattern can be determined based on the numerical value. Further, since the mounting test printed wiring board is deformed by applying a bending stress, it is possible to easily detect peeling and connection failure that could not be found without deforming the mounting test printed wiring board.

  The mounting test method according to the present invention may be characterized in that a light emitting device that emits light when a change in an energized state is detected is used as the energization detecting means.

  With this configuration, when a change in the energization state is detected by the energization detection means, the energization detection means emits light, so that the location where the energization state has changed can be identified by visual inspection, and the occurrence of peeling or poor connection can be identified. It can be grasped instantly. Therefore, the test operator can easily determine whether or not the land pattern design is appropriate.

  According to the mounting test apparatus of the present invention, when the mounting test simulated electronic component is mounted on the mounting test printed wiring board, the terminal land of the mounting test printed wiring board and the connection terminal of the mounting test simulated electronic component Constitutes one or a plurality of series circuits starting from one of the measurement pads and ending at the other, and current is passed through the series circuit, while adjacent terminal lands that are not connected to each other in the terminal lands. Since the energization detection means is connected and the energization state between the terminal lands is detected, it is possible to detect whether peeling or poor connection has occurred in the connection state between the connection terminal and the terminal land at a plurality of locations substantially simultaneously. As a result, the suitability of the land pattern design can be determined in a short time.

  In addition, since the connection state between the connection terminal and the terminal land is detected by the energization detection means, even if the joint between the connection terminal and the terminal land cannot be visually observed due to the package structure of the electronic component, The connection state with the terminal land can be grasped.

  Further, according to the mounting test apparatus of the present invention, since the energization detecting means is equipped with a light emitting device that emits light when a change in the energized state is detected, the location where the energized state has changed is visually identified. It is possible to instantly grasp the location where peeling or connection failure occurs. Therefore, the test operator can easily determine whether or not the land pattern design is appropriate.

  According to the mounting test method of the present invention, mounting the simulated electronic component for mounting test on the printed wiring board for mounting test, and connecting the terminal land of the printed wiring board for mounting test and the connecting terminal of the simulated electronic component for mounting test. By connecting, one or a plurality of series circuits with one of the measurement pads as the starting point and the other as the ending point are formed, and a current is passed through the series circuit, while the terminal lands are adjacent to each other not connected to each other. By detecting the current-carrying state between the terminal lands by connecting the current-carrying detection means between the terminal lands, it is possible to detect whether or not peeling or poor connection has occurred in the connection state between the connection terminal and the terminal land at approximately the same time. As a result, the suitability of the land pattern design can be determined in a short time.

  In addition, since the connection state between the connection terminal and the terminal land is detected by the energization detection means, even if the joint between the connection terminal and the terminal land cannot be visually observed due to the package structure of the electronic component, The connection state with the terminal land can be grasped.

  Further, according to the mounting test method according to the present invention, since peeling and connection failure occurring in the connection terminal and the terminal land are detected in a state where bending stress is applied to the printed wiring board for mounting test, peeling and connection failure are detected. Since the generated bending stress value can be acquired, the suitability of the designed land pattern can be determined based on the numerical value. Further, since the mounting test printed wiring board is deformed by applying a bending stress, it is possible to easily detect peeling and connection failure that could not be found without deforming the mounting test printed wiring board.

  Further, according to the mounting test method according to the present invention, since the light emitting device that emits light when the change in the energization state is detected is used as the energization detection means, it is possible to visually identify the location where the energization state has changed. It is possible to instantly grasp the location where peeling or connection failure occurs. Therefore, the test operator can easily determine whether or not the land pattern design is appropriate.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
In this embodiment, a mounting test apparatus for testing suitability of a land pattern for mounting an IC of a QFP package having 12 connection terminals will be described.

  FIG. 1 is a schematic view of a mounting test apparatus for testing suitability of land pattern design.

  The mounting test apparatus 7 for testing the suitability of the design of the land pattern 20 includes a printed wiring board for mounting test 1 on which a land pattern 20 corresponding to an electronic component to be mounted is formed, and a printed wiring board for mounting test in the test. And a power supply means 75 for applying a voltage to the series circuit formed when the mounting test simulated electronic component 2 is mounted on the mounting test printed wiring board 1; The terminal land 21 is composed of energization detecting means 3 connected between adjacent terminal lands 21 and 21 which are not connected to each other. The mounting test apparatus 7 includes a stage 70 for fixing the printed wiring board 1 for mounting test.

  FIG. 2 is a front view of a mounting test printed wiring board constituting the mounting test apparatus according to the first embodiment.

  The printed wiring board for mounting test 1 is formed for mounting testing in order to test the suitability of the design of the land pattern 20 formed on the printed wiring board corresponding to the electronic component to be mounted.

  Specifically, the mounting test printed wiring board 1 is formed with two measurement pads 23 and 23 and a land pattern 20 according to the design. Each of the two measurement pads 23 and 23 is connected to the terminal lands 21 and 21 on a one-to-one basis. The terminal lands 21 connected to the measurement pads 23 are independent of other terminal lands 21 and are independent, and these terminal lands 21 are configured as a pad connection group. On the other hand, the terminal lands 21 other than the pad connection group are connected to each other by the connection pattern 22 for each set as one set. The terminal lands 21 connected as a set of two are configured as a pair connection group.

  In other words, the terminal land 21 constituting the land pattern 20 includes two pad lands 21 each having one-to-one connection with the measurement pads 23 and two terminal lands 21 other than the pad connection group. As a set, each set is divided into a pair connection group that is connected to each other.

  For example, referring to the reference numerals in FIG. 2, the pad connection group is composed of individual terminal lands 21 (1) and (12), and the pad connection groups are (2) (3), (4) (5). ,..., (10) and (11).

  The land pattern 20 configured as described above is formed at a predetermined position (for example, a position where it is actually formed) on the printed wiring board 1 for mounting test. Moreover, you may process the external shape of the printed wiring board 1 for mounting tests into the external shape similar to an actual printed wiring board. In this way, in the mounting test for testing the suitability of the design of the land pattern 20 by forming the printed wiring board 1 for mounting test in the form of an actual printed wiring board, the land pattern 20 in actual mounting or environmental change. As a result, the suitability of the design of the land pattern 20 can be evaluated more appropriately.

  The connection between the pair of terminal lands 21 and 21 is not limited to the connection by the connection pattern 22 but may be connected by other methods. For example, a set of two terminal lands 21 and 21 may be connected to each other by solder or a conductive adhesive.

  FIG. 3 is a front perspective view of the mounting test simulated electronic component constituting the mounting test apparatus according to the first embodiment.

  The simulated electronic component 2 for mounting test is for mounting on the land pattern 20 formed on the printed wiring board 1 for mounting test when testing the suitability of the design of the land pattern 20.

  Specifically, the mounting test simulated electronic component 2 is formed with a connection terminal 11 simulating the connection terminal arrangement of the electronic component to be mounted. In the present embodiment, the mounting test simulated electronic component 2 is a QFP package imitating an IC that is to be mounted.

  In the connection terminal 11, the connection terminals 11 and 11 corresponding to the adjacent terminal lands 21 that are not connected to each other in the terminal land 21 are short-circuited. That is, in the adjacent terminal lands 21, the connection terminals 11 and 11 that are in contact with the terminal lands 21 and 21 that are not connected to each other by the connection pattern 22 are short-circuited to each other by the connection line 12. The connection terminals 11 and 11 short-circuited as a pair constitute a pair terminal group.

  The connection between the connection terminals 11 and 11 will be described with reference to the reference numerals in FIG. The connection terminals 11 of the mounting test simulated electronic component 2 shown in FIG. 3 have the same reference numerals as the corresponding terminal lands 21 corresponding to the terminal lands 21 of the land pattern 20 shown in FIG. It is attached. The connection terminal 11 is short-circuited with two sets of (1) and (2), (3) and (4),..., (11) and (12). That is, a set of terminal lands 21 that are not connected to each other in the adjacent terminal lands 21, for example, (1) and (2), (3) and (4),. And the connection terminals 11 and 11 which contact | abut to (12) are short-circuited.

  As the connection line 12 that connects the connection terminals 11, 11, a wire having a resistance smaller than the load resistance equivalent to the energization detection means 3 (see FIG. 3) described later, such as a gold wire, is used.

  Note that the connection terminals 11 and 11 may be connected by other methods without using a gold wire or the like. For example, the connection terminals 11 and 11 may be short-circuited by soldering.

  Such a mounting test simulated electronic component 2 uses, for example, a lead frame 10 similar to an electronic component to be mounted, and short-circuits the predetermined connection terminals 11 and 11 shown above by wire bonding with a gold wire. Further, it is formed by sealing a gold wire with a sealing resin 13. In FIG. 3, an IC is not mounted on the IC mounting portion 19 on which the IC chip is mounted. However, the mounting test simulated electronic component 2 may be configured by mounting an IC.

  In this way, the land pattern 20 of the printed wiring board 1 for mounting test is connected to the two terminal lands 21, 21 in a one-to-one relationship with the measurement pads 23, 23, and other than the two terminal lands 21, 21. On the other hand, the mounting test simulated electronic components 2 correspond to adjacent terminal lands 21 that are not mutually connected in the terminal land 21. By configuring the connection terminals 11 so as to be short-circuited, when the mounting test simulated electronic component 2 is mounted on the land pattern 20, the terminal land 21 and the connection terminal 11 start one of the measurement pads 23, A series circuit having the other end point is configured.

  Since this series circuit is formed so as to pass through a plurality of joints formed by connecting the connection terminal 11 and the terminal land 21, the series circuit is connected to both ends of the series circuit. By applying a voltage to the pads 23, 23, current can be passed through all junctions.

  The power supply means 75 is for supplying current to a series circuit formed by mounting the mounting test simulated electronic component 2 on the mounting test printed wiring board 1, and is constituted by, for example, a voltage power source or a current power source. Is done. The voltage power source or the current power source is provided with a protection circuit for preventing an excessive current from flowing through the mounting test simulated electronic component 2. In the test of the suitability of the design of the land pattern 20, the terminal of the power supply means 75 is connected to the measurement pad 23.

  The energization detecting means 3 is connected between the adjacent terminal lands 21 and 21 which are not connected to each other in the terminal land 21, and detects the energized state between the terminal lands 21 and 21, and this terminal land. When the connection between 21 and 21 is interrupted, the current can be passed to the energization detecting means 3 side.

  That is, the energization detecting means 3 is connected to a connection line 12 connecting a predetermined terminal land 21, 21 via a pair of connection terminals 11, 11 connected to the terminal land 21, 21. When the connection terminals 11 and the terminal lands 21 are separated and the current does not flow to the connection line 12 due to the separation of the connection terminals 11 and the terminal lands 21, the energization connected in parallel to the connection line 12 is performed. While passing an electric current to the detection means 3 side, it detects that the location connected to the electricity supply detection means 3 became a disconnection state by measuring an electric current.

  With this configuration, it is possible to detect the energization state between the terminal lands 21 and 21 to which the energization detection means 3 is connected, and the connection terminals 11 and the terminal lands 21 are partially separated to make the series circuit non-conductive. Even so, since the current can be passed through the energization detecting means 3 connected to this non-connection location, the supply of current to the series circuit is not stopped, and the connection terminal 11 and the terminal land 21 at other locations Current can be passed through the junction. That is, by connecting the energization detecting means 3 between the plurality of terminal lands 21 and 21, respectively, it is possible to simultaneously detect the energization state at that location between the plurality of terminal lands 21 and 21.

  Specifically, the energization detection means 3 is connected to the load lands 21 and 21 so as to short-circuit between the terminal lands 21 and 21 (as described above, the resistance value from the connection line 12). And a current detection device for detecting the current flowing through the load resistance. With this configuration, when the connection terminal 11 and the terminal land 21 are connected between the terminal lands 21 and 21 to which the energization detecting means 3 is connected, the load resistance has a higher resistance value than the connection line 12, so that the current On the other hand, when the connection terminal 11 and the terminal land 21 are peeled off between the terminal lands 21 and 21, and a disconnection or a connection failure occurs, a part or all of the current flows to the load resistance, A current flowing through the load resistance is detected by the current detection device, and a current conduction failure between the terminal lands 21 and 21 is detected.

  Alternatively, the energization detection means 3 is a load resistor (having a resistance value higher than that of the connection line 12 as described above) arranged so as to short-circuit between the terminal lands 21 and 21 when connected between the terminal lands 21 and 21. ) And a voltage detection device that detects a change in the voltage of the load resistance. With this configuration, when the connection terminal 11 and the terminal land 21 are connected between the terminal lands 21 and 21 to which the energization detecting means 3 is connected, the load resistance has a higher resistance value than the connection line 12, so that the current On the other hand, when the connection terminal 11 and the terminal land 21 are separated between the terminal lands 21 and 21, and the connection is cut or poorly connected, a part or all of the current flows to the load resistance. At the same time, the voltage change of the load resistance is detected by the voltage detection device, and the conduction failure between the terminal lands 21 and 21 is detected.

  The energization detection means 3 may include a light emitting device that emits light when a current flowing through the load resistance is detected or when a voltage change of the load resistance is detected. With this configuration, since the light emitting device emits light when the connection terminal 11 and the terminal land 21 are peeled off or poorly connected, it is possible to easily identify the part where the peeling or poor connection is made visually. The location where the connection failure occurs can be grasped instantly. Therefore, the test operator can easily determine whether or not the land pattern design is appropriate.

  The energization detection means 3 is connected between predetermined terminal lands 21 and 21 by, for example, a conductive wire. The conductive wire is preferably formed in advance on the printed wiring board 1 for mounting test as a conductor pattern. As a result, it is possible to eliminate the bonding between the terminal land 21 and the conductor pattern. Therefore, even when the test is performed by deforming the printed wiring board 1 for mounting test, the conductor pattern is not cut from the terminal land 21, so that it is stable. A test can be performed.

  Further, the mounting test apparatus 7 may be provided with a load device for applying a load to the mounting test printed wiring board 1 in order to test the mounting test printed wiring board 1 with a bending stress applied.

  FIG. 4 is an explanatory diagram of a state in which a load is applied to the printed wiring board for mounting test by the load device.

  The load device 60 includes a support fixing jig 61 that supports the lower surface of the mounting test printed wiring board 1 while being separated from the stage 70, and a loader 65 that applies a load to the mounting test printed wiring board 1.

  When bending stress is applied to the printed wiring board 1 for mounting test, both ends of the printed wiring board 1 for mounting test are supported by support fixing jigs 61 and 61, and the vicinity of the center is loaded by a loader 65, as shown in FIG. The load is applied in the direction of the arrow shown in the figure. At this time, the load value (bending stress value) of the loader 65 is measured.

  With this configuration, it is possible to detect peeling or connection failure occurring in the connection terminal 11 and the terminal land 21 in a state where bending stress is applied to the printed wiring board 1 for mounting test. Moreover, since the load value (bending stress value) at which peeling or poor connection occurs can be acquired, the suitability of the designed land pattern 20 can be determined based on the numerical value. Furthermore, since the mounting test printed wiring board 1 is deformed by applying a bending stress, it is possible to easily detect peeling or connection failure that could not be found without deforming the mounting test printed wiring board 1. it can.

  Next, the operation of the mounting test apparatus 7 that tests the suitability of the design of the land pattern 20 will be described.

  First, the mounting test simulated electronic component 2 is mounted on the land pattern 20 of the mounting test printed wiring board 1, and the connection terminals 11 and the terminal lands 21 are connected by solder. The connection by soldering is performed by a reflow process, for example. As a result, a series circuit in which the connection terminals 11... And the terminal lands 21.

  The terminals of the power supply means 75 are connected to the inspection pads 23 and 23 of the printed wiring board 1 for mounting test. The energization detection means 3 is connected between the adjacent terminal lands 21 and 21 that are not connected to each other in the terminal land 21 as described above. The power supply means 75 is connected to the test pads 23 and 23, and current is supplied to the series circuit.

  When there is no separation or connection failure between all the connection terminals 11 and the terminal lands 21, a current flows through a series circuit starting from one of the measurement pads 23, 23 and ending at the other. Therefore, no current flows through the energization detection means 3, and no abnormality in the energization state at the location where the energization detection means 3 is connected is detected. Therefore, the suitability of the design of the land pattern 20 is determined to be good.

  On the other hand, when there is separation or connection failure between any of the connection terminals 11 and the terminal land 21, a current flows through the energization detection means 3 connected to the terminal land 21 where separation or connection failure occurs. Since the abnormality of the energized state at this point is detected, the suitability of the design of the land pattern 20 is determined to be defective.

  Further, when the mounting test apparatus 7 is provided with the load device 60, the mounting test printed wiring board 1 is deformed by applying a load by the load device 60, and a current is passed through the series circuit in the deformed state, and the connection terminal It may be confirmed whether or not there is a peeling or connection failure between the terminal 11 and the terminal land 21. In this case, since a test is performed by applying a load (bending stress load) to the printed wiring board 1 for mounting test, it is possible to obtain a load value that causes separation or connection failure between the connection terminal 11 and the terminal land 21. Thus, the load resistance characteristics of the land pattern 20 can be evaluated.

  According to the mounting test apparatus 7 for testing the suitability of the design of the land pattern 20, when the mounting test simulated electronic component 2 is mounted on the mounting test printed wiring board 1, the terminals of the mounting test printed wiring board 1. The land 21 and the connection terminal 11 of the mounting test simulated electronic component 2 constitute one or a plurality of series circuits starting from one of the measurement pads 23 and ending at the other, and a current is passed through the series circuit. Since the energization detecting means 3 is connected between the adjacent terminal lands 21 and 21 which are not connected to each other in the terminal land 21 and the energization state between the terminal lands 21 and 21 is detected, a plurality of locations are connected substantially simultaneously. It is possible to detect whether or not peeling or connection failure has occurred in the connection state between the terminal 11 and the terminal land 21. As a result, the land pattern 20 can be designed in a short time. It can be determined.

  In addition, since the connection state between the connection terminal 11 and the terminal land 21 is detected by the energization detection means 3, the joint between the connection terminal 11 and the terminal land 21 cannot be visually observed due to the package structure such as an electronic component of the QFN package. Even so, the connection state between the connection terminal 11 and the terminal land 21 can be grasped.

  In the present embodiment, the land pattern 20 for mounting an IC having an even number of connection terminals 11 has been described. However, the present invention is also applied to a land pattern 20 for mounting an IC having an odd number of connection terminals 11. The

  In this case, by removing one terminal land 21 and one connection terminal 11 corresponding thereto, the present invention is applied with the terminal land 21 and connection terminal 11 being an even number. Thereafter, the connection state between one excluded terminal land 21 and one corresponding connection terminal 11 is separately inspected.

  In this embodiment, in order to test the suitability of the design of the land pattern 20 for mounting the IC of the QFP package, the mounting test apparatus 7 is a printed wiring board for mounting test formed based on the QFP package. 1 and the mounting test simulated electronic component 2 are constituent elements. When testing the suitability of the land pattern 20 for mounting other electronic components, the mounting test is performed based on the package of the electronic component. A printed wiring board 1 and a simulated electronic component 2 for mounting test are formed and used as components of the mounting test apparatus 7.

<Embodiment 2>
In the present embodiment, an example in which the mounting test printed wiring board 1 and the mounting test simulated electronic component 2 are configured so that two series circuits are formed in the land pattern 20 related to the test will be described.

  FIG. 5 is a schematic view of a mounting test apparatus for testing the suitability of the land pattern design.

  The mounting test apparatus 7 includes a mounting test printed wiring board 1 on which a land pattern 20 corresponding to an electronic component to be mounted is formed, and a mounting test simulated electronic component 2 mounted on the mounting test printed wiring board 1 in the test. And a power supply means 75 for applying a voltage to a series circuit formed when the mounting test simulated electronic component 2 is mounted on the mounting test printed wiring board 1 and the terminal land 21 not adjacent to each other Power supply detecting means 3 connected between the terminal lands 21 and 21 to be connected. The mounting test apparatus 7 may include a stage 70 for fixing the printed wiring board 1 for mounting test.

  The printed wiring board for mounting test 1 is a printed wiring board formed for mounting testing in order to test the suitability of the design of the land pattern 20 formed on the printed wiring board corresponding to the electronic component to be mounted. is there. In the present embodiment, the terminal lands 21 constituting the land pattern 20 are divided into two groups so that the two independent systems can be inspected when the suitability of the design of the land pattern 20 is tested. Yes.

  Specifically, on the printed wiring board 1 for mounting test, four measurement pads 23 and a land pattern 20 according to the design are formed. The terminal lands 21 constituting the land pattern 20 are divided into two groups, and the two measurement pads 23 are assigned to one group, while the other two measurement pads 23 are assigned to the other group. Be assigned.

  Further, in each group, the two measurement pads and the terminal land 21 are configured as shown in the first embodiment. That is, each of the two measurement pads 23 and 23 is connected to the terminal lands 21 and 21 on a one-to-one basis. The terminal lands 21 connected to the measurement pads 23 are independent of other terminal lands 21 and are independent, and these terminal lands 21 are configured as a pad connection group. On the other hand, the terminal lands 21 other than the pad connection group are connected to each other by the connection pattern 22 for each set as one set. The terminal lands 21 connected as a set of two are configured as a pair connection group.

  The simulated electronic component 2 for mounting test is for mounting on the land pattern 20 formed on the printed wiring board 1 for mounting test when testing the suitability of the design of the land pattern 20. In the present embodiment, the connection terminals 11 are divided into two groups so that the two independent systems can be inspected when the suitability of the design of the land pattern 20 is tested.

  Specifically, the mounting test simulated electronic component 2 is formed as a connection terminal 11 simulating the connection terminal arrangement of the electronic component to be mounted, and the connection terminal 11 is divided into two groups. It is divided into two groups so as to correspond to the terminal lands 21 formed.

  In each group, connection terminals 11 are short-circuited between connection terminals 11 and 11 corresponding to adjacent terminal lands 21 that are not connected to each other in terminal lands 21. That is, the connection terminals 11 and 11 that are in contact with the terminal lands 21 and 21 that are not connected to each other by the connection pattern 22 in the adjacent terminal lands 21 are short-circuited by the connection line 12 and short-circuited as a set of two. The connected terminals 11 and 11 constitute a pair terminal group.

  In this way, the land pattern 20 of the printed wiring board 1 for mounting test is divided into two groups, while the simulated electronic component 2 for mounting test is divided into two groups corresponding to the grouping of the land pattern 20. Thus, when the mounting test simulated electronic component 2 is mounted on the land pattern 20, one of the measurement pads 23 is formed by the terminal land 21 of the mounting test printed wiring board 1 and the connection terminal 11 of the mounting test simulated electronic component 2. As a starting point, two series circuits having the other end point are configured.

  The power supply means 75 is for supplying a current to a series circuit formed by mounting the mounting test simulated electronic component 2 on the mounting test printed wiring board 1, and is supplied to the measurement pads 23, 23 of each group. Connected.

  Note that the pair of measurement pads 23 and 23 in one group and the pair of measurement pads 23 and 23 in the other group may be common. According to this configuration, current can be supplied to the two series circuits by connecting the power supply means 75 to the pair of measurement pads 23 and 23.

  The energization detection means 3 is connected between adjacent terminal lands 21 and 21 not connected to each other in each group, and detects an energization state between the terminal lands 21 and 21. When the gap is interrupted, the current can be passed to the energization detecting means 3 side.

  With this configuration, it is possible to detect the energization state between the terminal lands 21 and 21 to which the energization detection means 3 is connected, and the connection terminals 11 and the terminal lands 21 are partially separated to make the series circuit non-conductive. Even so, since the current can be passed through the energization detecting means 3 connected to this non-connection location, the supply of current to the series circuit is not stopped, and the connection terminal 11 and the terminal land 21 at other locations Current can be passed through the junction. That is, by connecting the energization detecting means 3 between the plurality of terminal lands 21 and 21, respectively, it is possible to simultaneously detect the energization state at that location between the plurality of terminal lands 21 and 21.

  According to the mounting test apparatus 7 that tests the suitability of the design of the land pattern 20, the connection between the connection terminals 11 and the terminal lands 21 is performed at almost the same time as in the effect of the mounting test apparatus 7 according to the first embodiment. It is possible to detect whether peeling or poor connection occurs in the state, and as a result, whether or not the land pattern 20 is designed can be determined in a short time.

  In addition, since the land patterns 20 are configured in two independent groups, when the suitability of the design of the land patterns 20 is tested, the two independent systems can be inspected. Therefore, even when testing the suitability of the design of the land pattern 20 composed of a large number of terminal lands 21 exceeding 100, the components (connections) forming the series circuit by dividing into two groups Since the number of terminals 11 and terminal lands 21) can be reduced, the test execution is uncertain that the test is interrupted by disconnection at a portion other than the joint between the connection terminal 11 and the terminal land 21 to be evaluated. Can be reduced.

  In the present embodiment, the land pattern 20 related to the test is divided into two groups. However, the present invention is not limited to two groups, and may be divided into a large number of groups.

<Embodiment 3>
Next, a method for testing suitability of the design of the land pattern 20 will be described with reference to FIGS.

  The method for testing the suitability of the design of the land pattern 20 uses the printed wiring board 1 for mounting test and the simulated electronic component 2 for mounting test shown in the first or second embodiment. Since the configurations of the printed wiring board for mounting test 1 and the simulated electronic component 2 for mounting test are the same as those shown in the first or second embodiment, the description thereof is omitted.

  When testing the design suitability of the land pattern 20, first, the mounting test simulated electronic component 2 is mounted on the land pattern 20 of the mounting test printed wiring board 1, and the connection terminals 11 and the terminal lands 21 are connected by soldering. To do. As a result, a series circuit is formed in which one of the measurement pads 23 is the starting point and the other is the ending point.

  Next, the mounting test printed wiring board 1 on which the mounting test simulated electronic component 2 is mounted is deformed by the load device 60 or the like, and a load is applied to the connection portion between the connection terminal 11 and the terminal land 21. Thus, it is tested whether or not the designed land pattern 20 can withstand the deformation.

  Next, the energization detection means 3 having the same configuration as that of the first or second embodiment is connected between the adjacent terminal lands 21 and 21 that are not connected to each other.

  Next, the power supply means 75 described in the first or second embodiment is connected to the measurement pads 23 and 23 formed on the printed wiring board 1 for mounting test, and a current is passed through the series circuit. Then, the energization detection means 3 connected between the predetermined terminal lands 21 and 21 confirms whether or not a change in the energization state is detected at each location, and determines whether the land pattern 20 is suitable for design.

  Further, the printed wiring board for mounting test 1 may be inspected while applying a load (bending stress load). In this case, the load value when peeling occurs between the connection terminal 11 and the terminal land 21 is confirmed.

  According to such a mounting test method for testing the suitability of the design of the land pattern 20, the mounting test simulated electronic component 2 is mounted on the mounting test printed wiring board 1, and the terminal land 21 of the mounting test printed wiring board 1. And the connection terminal 11 of the mounting test simulated electronic component 2 constitute one or a plurality of series circuits in which one of the measurement pads 23 is the starting point and the other is the ending point. On the other hand, since the energization detecting means 3 is connected between the adjacent terminal lands 21 and 21 which are not connected to each other in the terminal land 21 to detect the energized state between the terminal lands 21 and 21, a plurality of locations are omitted. At the same time, it is possible to detect whether peeling or poor connection occurs in the connection state between the connection terminal 11 and the terminal land 21. As a result, the land pattern 2 can be detected in a short time. It is possible to determine the suitability of the design of.

  Further, since the connection state between the connection terminal 11 and the terminal land 21 is detected by the energization detection means 3, the joint between the connection terminal 11 and the terminal land 21 cannot be visually observed due to the package structure of the electronic component. In addition, the connection state between the connection terminal 11 and the terminal land 21 can be grasped.

  Furthermore, when the printed wiring board 1 for mounting test is subjected to a test by applying a load (bending stress load) by the load device 60, it is possible to obtain a load value (bending stress value) at which peeling or poor connection occurs. Since the suitability of the designed land pattern 20 can be determined based on the numerical value, the load resistance characteristics of the land pattern 20 can be evaluated. Further, since the mounting test printed wiring board 1 is deformed by applying a bending stress, it is possible to easily detect peeling or connection failure that cannot be found without deforming the mounting test printed wiring board 1. it can.

  Further, when a device equipped with a light emitting device that emits light when a change in the energized state is detected is used as the energization detecting means 3, the location where the energized state has changed can be identified by visual inspection. And the location where a connection failure occurs can be grasped instantly. Therefore, the test operator can easily determine whether or not the land pattern design is appropriate.

  It should be noted that the land pattern 20 may be tested for suitability without deforming the mounting test printed wiring board 1 mounted with the mounting test simulated electronic component 2 by the load device 60 or the like. In this case, whether or not the designed land pattern 20 is designed to have a size that matches the connection terminal 11 of the simulated electronic component 2 for mounting test imitating the electronic component to be mounted is tested. Become. That is, the dimension of the designed land pattern 20 is shifted from the connection terminal 11 of the electronic component to be mounted, and when the mounting test simulated electronic component 2 is mounted on the printed wiring board 1 for mounting test, When non-bonding occurs with the connection terminal 11, the location is specified by the test method described above. Therefore, the suitability of the design dimension of the land pattern 20 is determined by such a test method.

It is the schematic of the mounting test apparatus for testing the suitability of the design of a land pattern. 1 is a front view of a printed wiring board for mounting test that constitutes a mounting test apparatus according to Embodiment 1. FIG. FIG. 3 is a front perspective view of a mounting test simulated electronic component constituting the mounting test apparatus according to the first embodiment. It is explanatory drawing of the state which applied the load to the printed wiring board for mounting tests with the load apparatus. It is the schematic which shows other embodiment of the mounting test apparatus for testing the suitability of the design of a land pattern. It is explanatory drawing explaining the method to test | inspect a land pattern by applying the conventional method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printed wiring board for mounting tests 2 Simulated electronic component for mounting tests 3 Current detection means 7 Mounting test apparatus 11 Connection terminal 12 Connection line 20 Land pattern 21 Terminal land 22 Connection pattern 23 Measurement pad 60 Loading device 70 Stage 75 Power supply means

Claims (5)

A mounting test apparatus for testing the suitability of the design of a land pattern formed on a printed wiring board corresponding to an electronic component to be mounted,
At least two measurement pads and a land pattern according to the design are formed, and the terminal land constituting the land pattern is a pad connection group consisting of terminal lands connected to each of the measurement pads on a one-to-one basis. A printed circuit board for mounting test divided into one or a plurality of pair connection groups each of which is connected to each other as a set of two terminal lands other than the pad connection group;
A simulation for mounting test comprising a connection terminal imitating an electronic component to be mounted, and among these connection terminals, connection terminals corresponding to adjacent terminal lands that are not mutually connected in the terminal lands are short-circuited. Electronic components,
Energization detecting means connected between adjacent terminal lands that are not mutually connected in the terminal lands;
Power supply means connected to the measurement pads of the mounting test printed wiring board,
When the mounting test simulated electronic component is mounted on the mounting test printed wiring board, the measurement pad is formed by the terminal land of the mounting test printed wiring board and the connection terminal of the mounting test simulated electronic component. One or a plurality of series circuits starting from one side and ending at the other side are configured, and whether or not the land pattern is designed is determined by the state of the current flowing through the energization detecting means. Test equipment.   The mounting test apparatus according to claim 1, wherein the energization detecting unit includes a light emitting device that emits light when a change in an energized state is detected. A mounting test method for testing suitability of the design of a land pattern formed on a printed wiring board corresponding to an electronic component to be mounted,
At least two measurement pads and a land pattern according to the design are formed, and the terminal land constituting the land pattern is a pad connection group consisting of terminal lands connected to each of the measurement pads on a one-to-one basis. While forming a printed wiring board for mounting test divided into one or a plurality of pair connection groups that are connected to each other as a set of two terminal lands other than this pad connection group,
A simulation for mounting test comprising a connection terminal imitating an electronic component to be mounted, and among these connection terminals, connection terminals corresponding to adjacent terminal lands that are not mutually connected in the terminal lands are short-circuited. Forming electronic components,
By mounting the mounting test simulated electronic component on the mounting test printed wiring board, the terminal pad of the mounting test printed wiring board and the connection terminal of the mounting test simulated electronic component of the measurement pad Configure one or a plurality of series circuits starting from one and ending at the other, and connect the energization detecting means for detecting the energization state between adjacent terminal lands that are not connected to each other in the terminal lands In the mounted state, power is supplied from the power supply means to the series circuit via the measurement pad, and the suitability of the land pattern design is determined according to the state of the current flowing through the energization detection means. Test method.   The mounting test method according to claim 3, wherein the mounting test is performed in a state in which bending stress is applied to the printed wiring board for mounting test.   The mounting test method according to claim 3 or 4, wherein a light emitting device that emits light when a change in an energized state is detected is used as the energization detecting means.

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