JP3857404B2 - Printed wiring board - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printed wiring board for mounting a surface-mount type electronic component having a solder pad on the back surface, and more particularly to a mark technique for checking whether or not there is a mounting deviation of an electronic component.
[0002]
[Prior art]
In recent years, surface mounting type has become mainstream as a mounting form of electronic components such as LSI packages. As surface mount electronic components, there are many BGA (Ball Grid Array) type and CSP (Chip Scale / Size Package) type having solder pads on the back side. In order to mount an electronic component having a plurality of solder pads, a plurality of connection pads corresponding to the solder pads are formed on the printed wiring board. Hold the electronic component by the mounter head, move the mounter head to align the solder pad of the electronic component and the connection pad of the printed wiring board, perform solder reflow, and lower the mounter head to lower the electronic component. Each solder pad is electrically and mechanically joined to each connection pad of the printed wiring board, and electronic components are mounted on the printed wiring board.
[0003]
In this mounting, the solder pad and the connection pad are hidden under the package of the electronic component. Therefore, when mounting is performed with simple alignment, the solder pad is bonded to the connection pad while being displaced. There is a risk of being. Even if an attempt is made to check for mounting misalignment after mounting, it is difficult to check because the joint is hidden.
[0004]
Therefore, in order to make it possible to confirm whether or not there is a mounting deviation after mounting an electronic component, a method as shown in FIG. In the printed wiring board 1, a rectangular annular mounting displacement confirmation pattern 3 is formed around the plurality of connection pads 2 formed thereon by silk screen printing. A plurality of solder pads 5 are provided on the back surface of the electronic component 4. On the printed wiring board 1, the connection pads 2 are formed in a state corresponding to the solder pads 5 with respect to the size, pitch, pattern, and the like. The rectangular annular mounting deviation confirmation pattern 3 is silk-screen printed in a state matching the outer shape of the electronic component 4.
[0005]
The connection pad 2 is formed in the same process as a wiring pattern (not shown), and both the connection pad 2 and the wiring pattern are copper. However, silk-screen printing of the rectangular annular mounting deviation confirmation pattern 3 is a separate process from the connection pad 2.
[0006]
When the electronic component 4 is mounted on the printed circuit board 1, the outer shape of the electronic component 4 is positioned on the rectangular annular mounting displacement confirmation pattern 3 using the rectangular annular mounting displacement confirmation pattern 3 by silk screen printing as an aid for alignment. In this state, the solder pad 5 is bonded to the connection pad 2.
[0007]
However, since the formation process of the connection pad 2 and the printing process of the rectangular annular mounting deviation confirmation pattern 3 are separate, the accuracy of the relative positional relationship of the rectangular annular mounting deviation confirmation pattern 3 with respect to the connection pad 2 is generally low. Is. There is a possibility that the position is shifted in the X direction, the position is shifted in the Y direction, the position is shifted in both the X and Y directions, or the rotation is shifted. FIG. 14 illustrates an example in which the rectangular annular mounting deviation confirmation pattern 3 is displaced with respect to the connection pad 2 in both the X and Y directions. As a result, if the square annular mounting displacement confirmation pattern 3 is used for confirming the presence or absence of mounting displacement, there is a risk of erroneous determination. That is, in the confirmation of the presence or absence of mounting deviation after mounting, as shown in FIG. 15, even if the outer shape of the electronic component 4 just overlaps the rectangular annular mounting deviation confirmation pattern 3, There is a possibility that the solder pad 5 is largely displaced. The fact that the outer shape of the electronic component 4 just overlaps the rectangular annular mounting deviation confirmation pattern 3 itself does not guarantee accurate positioning of the solder pad 5 with respect to the connection pad 2. That is, since there is no guarantee of the accuracy of the relative positional relationship between the square annular mounting deviation confirmation pattern 3 and the connection pad 2, the effectiveness in confirming the presence or absence of the mounting deviation is poor.
[0008]
Next, a conventional technique described in JP-A-9-83093 will be described with reference to FIG. In FIG. 16, 11 is an electronic component, 12 is a solder pad provided on the back surface of the electronic component 11, 13 is a printed wiring board, 14 is a connection pad formed on the printed wiring board 13, and 15 is on the printed wiring board 13. The dotted marks 16 formed on the printed wiring board 13 are silk-screen printed on the printed wiring board 13 in a state of being directed from the dotted marks 15 in the X direction and the Y direction. The dotted marks 15 are formed at positions corresponding to the positions immediately below the four corner apexes of the electronic component 11. The dotted marks 15 are formed in the same process as the connection pads 14, and both the dotted marks 15 and the connection pads 14 are copper. The linear mark 16 by silk screen printing is formed in a separate process from the connection pad 14. While the accuracy of the relative positional relationship of the dot mark 15 with respect to the connection pad 14 is extremely high, the accuracy of the relative positional relationship of the linear mark 16 with respect to the connection pad 14 is low. Therefore, the linear mark 16 is auxiliary in determining whether or not there is a mounting deviation, and the main index is the dotted mark 15 to the last.
[0009]
[Problems to be solved by the invention]
Based on the four dot marks 15 that are the main indicators, the state of confirmation of the presence or absence of mounting deviation will be described.
[0010]
As shown in FIG. 17 (a), after mounting, if all of the four corner vertices of the electronic component 11 are exactly overlapped with the four dot marks 15, the presence or absence of mounting deviation is confirmed. It is determined that there is no mounting deviation.
[0011]
As shown in (b) to (d) of FIG. 17, when a number of dot marks 15 are separated from the corner apexes of the electronic component 11 by a certain dimension or more, in confirming whether there is a mounting deviation. It is determined that there is a mounting deviation.
[0012]
However, since the main mark 15 is dot-like, it is very difficult to confirm whether or not there is a mounting deviation, as is apparent from a comparison between FIGS. 17A and 17B. It has become. This is because it is not easy to determine whether it is a deviation dimension within an allowable range or a deviation dimension indicating a mounting failure by visual observation.
[0013]
Further, as shown in FIGS. 18A to 18D, when the auxiliary linear mark 16 is printed in a state of being displaced with respect to the dotted mark 15, whether there is a mounting deviation or not. In the confirmation, the linear mark 16 is not only invalid, but the presence of such a linear mark 16 not only makes the dotted mark 15 inconspicuous, but also makes the appearance very confusing. On the other hand, it will be difficult to understand the difference.
[0014]
By the way, if the rectangular annular mounting deviation confirmation pattern 3 as shown in FIG. 14 is formed of copper simultaneously with the connection pad 2 instead of silk screen printing, the rectangular annular mounting deviation confirmation pattern 3 and the connection pad 2 can be relative to each other. The accuracy of the positional relationship is extremely high, and it may be considered that a high-accuracy confirmation should be possible if such a square annular mounting deviation confirmation pattern 3 is checked for the presence or absence of a mounting deviation. However, although not shown, the printed wiring board 1 is formed with a wiring pattern continuous to the plurality of connection pads 2, and when the rectangular annular mounting displacement confirmation pattern 3 is formed with copper as described above, A plurality of wiring patterns are all short-circuited. That is, it is not possible to form the rectangular annular mounting deviation confirmation pattern 3 with copper at the same time as the connection pads 2.
[0015]
The present invention was devised in view of such circumstances, and improves the mounting misalignment confirmation workability compared to the conventional technology in which the mounting misalignment confirmation is mainly performed with dot marks as a main component. The purpose is to improve the accuracy of deviation confirmation.
[0016]
[Means for Solving the Problems]
  In the present invention, a printed wiring board provided with a wiring pattern for mounting an electronic component on a component mounting surface has a shape corresponding at least partially to the outer shape of the electronic component mounted on the component mounting surface, In addition, there is a component outline display body in which at least a part of the position corresponds to the position of the wiring pattern, and the component outline display body has a mounting displacement of the electronic component in a state where the electronic component is mounted at the mounting position. It is configured to be able to confirm the presence or absence from the outsideThe component outer shape display body has a mounting misalignment confirmation mark made of the same conductive material as the wiring pattern so as to substantially coincide with at least one corner apex of the outer shape of the electronic component in a regular mounting state. The mounting deviation confirmation mark is provided in a predetermined shape that partially matches the outer shape of the corner of the electronic component, and is positioned on any side of the outer shape of the electronic component in a regular mounting state. The mounting deviation confirmation assisting mark of the non-conductive material is substantially correspondingly formed, and the mounting deviation confirmation assisting mark is formed with a predetermined width and a predetermined length.The above-mentioned problem is solved by using a printed wiring board characterized by this.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a printed wiring board according to the present invention will be described below in detail with reference to the drawings.
[0018]
1A and 1B show an electronic component to be mounted. FIG. 1A is a bottom view of the upside-down state, and FIG. 1B is a front view of the upside-down state. The electronic component 21 is of a surface mount type BGA (Ball Grid Array) type or CSP (Chip Scale / SizePackage) type, and a plurality of hemispherical solder pads 22 are formed on the back surface thereof at a predetermined pitch and in a predetermined pattern. Is provided. Reference numeral 23 denotes a cut surface obtained by cutting one corner of the package at an inclination angle of 45 degrees in the vicinity of the first pin in order to confirm the pin number position of the electronic component 21. The length of the horizontal side and the length of the vertical side of the electronic component 21 are equal.
[0019]
FIG. 2 is a plan view showing a printed wiring board according to the embodiment. A plurality of copper connection pads 32 (inside concentric circles) are formed as wiring patterns on the component mounting surface of the printed wiring board 31 in a state where the plurality of solder pads 22 of the electronic component 21 and the pitch pattern are combined. In addition, diagonal parts on the lower left and upper right of the electronic component 21 when the electronic component 21 is normally mounted as a component outer shape display body having a shape corresponding to at least the outer shape of the electronic component mounted outside the array region of the connection pad 32 group. Two L-shaped (bent shape) marks 33 and 34 for confirming mounting deviation are formed of copper at positions corresponding to.
[0020]
Here, since the connection pad 32 as the wiring pattern and the L-shaped marks 33 and 34 as the component outline display bodies are formed in the same process, they have a corresponding positional relationship with a high degree of accuracy. That is, the surface of the printed wiring board 31 is plated with copper, and the copper plating is etched to pattern the connection pads 32 and the L-shaped marks 33 and 34 simultaneously. Therefore, the accuracy of the relative positional relationship of the L-shaped marks 33 and 34 with respect to the connection pad 32 is extremely high.
[0021]
After the connection pad 32 and the L-shaped marks 33 and 34 are formed, the surface of the printed wiring board 1 is coated with a solder resist 35 except for the position of the connection pad 32. The chipped portion 35a of the solder resist 35 excluding the position of the connection pad 32 is indicated by a line outside the concentric circles. The solder resist 35 is for preventing solder from adhering to portions other than the connection pads 32 when the electronic component 21 is soldered to the printed wiring board 31. When the solder resist 35 is transparent, the L-shaped marks 33 and 34 can be seen through. When the solder resist 35 is opaque, the positions and shapes of the L-shaped marks 33 and 34 can be recognized by the swelling.
[0022]
After coating the solder resist 35, a large L-shaped strip for assisting in confirming mounting displacement as a component outer shape display body having a shape corresponding to at least the outer shape of the electronic component mounted on the surface of the solder resist 35 by silk screen printing. Marks 36 and 37 are formed. Each L-shaped elongated strip mark 36, 37 is formed at a position corresponding to the outer shape of the electronic component 21.
[0023]
3A, 4 and 5 are plan views showing a state in which the electronic component 21 is mounted on the printed wiring board 31. FIG. In these drawings, illustration of the solder resist 35 is omitted. Of the concentric circles indicated by dotted lines, the smaller one is the solder pad 22 on the back surface of the electronic component 21, and the larger one is the connection pad 32 on the printed wiring board 31. FIG. 3A shows a perfect mounting state with no mounting deviation. FIG. 4 shows a mounting state when the electronic component 21 is slightly shifted in the lower right direction from the normal position, and FIG. 5 shows a mounting state when the electronic component 21 is slightly shifted in the upper left direction from the normal position. In the case of FIG. 4 and FIG. 5, although it is shifted, it is within the allowable range. As shown in FIG. 3A, the mounting state in which each center of the plurality of solder pads 22 on the back surface of the electronic component 21 substantially coincides with each center of the plurality of connection pads 32 of the printed wiring board 31 is referred to as “regular mounting”. It will be called "state". Although there is a deviation as shown in FIGS. 4 and 5, the mounting state when the bonding state between each solder pad 22 and each connection pad 32 is within an allowable range is referred to as an “allowable mounting state”.
[0024]
Hereinafter, the state of formation of the L-shaped marks 33 and 34 for confirming the mounting deviation and the large L-shaped elongated strip-shaped marks 36 and 37 will be described in detail with reference to FIG. 3B is an enlarged view of the lower left L-shaped mark 33, FIG. 3C is an enlarged view of the upper right L-shaped mark 34, and FIG. 3D is an upper left inclined elongated band. It is an enlarged view of the part of the part 37c. Each of the L-shaped marks 33 and 34 includes a unidirectional component, in this case, horizontal strips 33a and 34a as a horizontal component, and another directional component in this case, vertical strips 33b and 34b as a vertical component. In addition, although the marks 33 and 34 are L-shaped, respectively, it is good to match the corner | angular part external shape of components, Therefore, it is not limited to this shape.
[0025]
The L-shaped elongated strip mark 36 includes a horizontal elongated strip portion 36a and a vertical elongated strip portion 36b. The L-shaped elongated strip mark 37 is composed of a horizontal elongated strip portion 37a, a vertical elongated strip portion 37b, and an inclined elongated strip portion 37c connecting them.
[0026]
In the following, the description will be in the regular implementation state until it is stated. The horizontal band 33a of the lower left L-shaped mark 33 has an inner side 33a.₁ Is formed so as to coincide with the lower side 21a of the outer shape of the electronic component 21, and the vertical band 33b is formed on the inner side 33b.₁ Is formed so as to coincide with the left side 21c of the outer shape of the electronic component 21, and the inner side 33a.₁ 33b₁ The inner corner vertex 33c where the two intersect each other is the corner vertex 21e of the outer shape of the electronic component 21.₁To match. The horizontal band 34a of the upper right L-shaped mark 34 has an inner side 34a.₁ Is formed so as to coincide with the upper side 21b of the outer shape of the electronic component 21, and the vertical band 34b is formed on the inner side 34b.₁ Is formed so as to coincide with the right side 21d of the outer shape of the electronic component 21, and the inner side 34a.₁ , 34b₁ The inner corner vertex 34c where the two intersect each other is the corner vertex 21e of the outer shape of the electronic component 21._Three To match. The widths of both L-shaped marks 33 and 34 are set to be equal to or larger than the allowable dimension for the amount of displacement of the solder pad 22 with respect to the connection pad 32. The width is about 0.2 mm, for example. The lengths of the horizontal band portions 33a and 34a and the vertical band portions 33b and 34b are each about 1.0 mm, for example. By forming the L-shaped marks 33 and 34 as described above, both the L-shaped marks 33 and 34 are not hidden by the electronic component 21 in a properly mounted state, and are formed so that all of them can be seen. Has been.
[0027]
The L-shaped marks 33 and 34 formed of copper, which is the same conductive material, at the same time as the connection pads 32 have a sufficiently short dimension of about 1.0 mm, so that they extend from the connection pads 32 and are on the printed wiring board 31. The L-shaped marks 33 and 34 are not short-circuited between the wiring patterns (not shown) formed in FIG. 5, and the L-shaped marks 33 and 34 do not hinder the design of the wiring patterns.
[0028]
Since the L-shaped strip-shaped marks 36 and 37 by silk screen printing are formed in a separate process from the connection pad 32, the relative positional relationship tends to be low, but here the relative positional relationship is exactly the same. The explanation will be made assuming that The horizontal elongated strip portion 36a of the large L-shaped elongated strip mark 36 at the lower right is an inner side 36a.₁ Is the inner side 33a of the horizontal band 33a of the lower left L-shaped mark 33₁ Is formed so as to coincide with the lower side 21a of the outer shape of the electronic component 21, and the vertical elongated band part 36b is formed on the inner side 36b.₁ Is the inner side 34b of the vertical band 34b of the L-shaped mark 34 at the upper right.₁ Is formed so as to coincide with the right side 21d of the outer shape of the electronic component 21, and the inner side 36a.₁ 36b₁ The inner corner vertex 36c where the intersections intersect is the corner vertex 21e of the outer shape of the electronic component 21.₂ To match. Further, the horizontal elongated strip portion 37a of the large L-shaped elongated strip mark 37 at the upper left is an inner side 37a thereof.₁ Is the inner side 34a of the horizontal strip 34a of the L-shaped mark 34 at the upper right.₁ Is formed so as to coincide with the upper side 21b of the outer shape of the electronic component 21, and the vertical elongated band portion 37b is formed on the inner side 37b.₁ Is the inner side 33b of the vertical band 33b of the lower left L-shaped mark 33₁ The slender elongated strip portion 37c is formed so as to coincide with the left side 21c of the outer shape of the electronic component 21 and the inner side 37c thereof.₁ Are formed so as to coincide with the cut surface 23 of the outer shape of the electronic component 21, and the inner side 37a is formed.₁ 37c₁ The inner corner vertex 37d where the two intersect with each other is the corner vertex 21e of the outer shape of the electronic component 21._Four And the inner side 37b₁ 37c₁ The inner corner vertex 37e where the intersections intersect is the corner vertex 21e of the outer shape of the electronic component 21._Five To match.
[0029]
The width of each L-shaped elongated strip mark 36, 37 is equal to the width of each L-shaped mark 33, 34. The outer side 36a of the horizontal elongated strip 36a₂ Is the outer side 33a of the horizontal strip 33a₂ The outer side 36b of the vertical elongated strip 36b₂ Is the outer side 34b of the vertical strip 34b₂ The outer side 37a of the horizontal elongated strip 37a₂ Is the outer side 34a of the horizontal strip 34a₂ The outer side 37b of the vertical elongated strip 37b.₂ Is the outer side 33b of the vertical strip 33b₂ It is on the extension line. The lengths of the horizontal elongated strip portion 36a and the vertical elongated strip portion 36b are equal to each other and are 80 to 90% of the length of one side of the electronic component 21. Moreover, the length of the horizontal elongate band part 37a and the vertical elongate band part 37b is equal, and is 70 to 80% of the length of one side of the electronic component 21. The dimension of the gap 38a between the horizontal band 33a and the horizontal elongated band 36a, the dimension of the gap 38b between the vertical band 33b and the vertical elongated band 37b, and the dimension of the gap 38c between the horizontal band 34a and the horizontal elongated band 37a. The dimensions of the gap 38d between the vertical belt portion 34b and the vertical elongated belt portion 36b are equal to each other, and are in the range of 50 to 100% of the length of each side of the L-shaped marks 33 and 34.
[0030]
By forming the L-shaped strip-shaped marks 36 and 37 as described above, both the L-shaped strip-shaped marks 36 and 37 are not hidden by the electronic component 21 in a properly mounted state, and all of them can be seen. It is formed to be in a state.
[0031]
When the electronic component 21 is mounted on the printed wiring board 31, the electronic component 21 is held by the mounter head, and the mounter head is moved to align the solder pad 22 of the electronic component 21 and the connection pad 32 of the printed wiring board 31. The solder pads 22 of the electronic component 21 are electrically and mechanically joined to the connection pads 32 of the printed wiring board 31 by performing solder reflow and lowering the mounter head. Implementation for 31 is performed. Even if the melted solder flows into the positions of the adjacent connection pads 32 and L-shaped marks 33 and 34, since it is on the solder resist 35, there is no problem of short circuit.
[0032]
After the electronic component 21 is mounted, whether or not there is a mounting deviation is checked.
[0033]
In the case of FIG. 3, the entire outer shape of the electronic component 21 is equally surrounded by the entire mounting misalignment confirmation marks formed by the two L-shaped marks 33, 34 and the two L-shaped elongated strip-shaped marks 36, 37. In other words, since it can be readily seen at a glance that the entire outer shape of the electronic component 21 is completely accommodated with respect to the entire mounting deviation confirmation mark, there is no normal mounting deviation. The mounting state can be easily determined.
[0034]
The case of FIG. 4 will be described. First, as a primary determination, all the outer sides 36a in relation to the L-shaped elongated strip marks 36, 37 having a length and a range almost comparable to the outer shape of the electronic component 21 are used.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. In the case of FIG. 4, it can be confirmed at a glance. Therefore, it can be predicted that it is an allowable mounting state as a primary determination. At the same time, the inner side 37a of the upper left L-shaped strip-shaped mark 37₁ 37b₁ 37c₁ On the other hand, since the outer shapes (upper side 21b, left side 21c, cut surface 23) of the electronic component 21 are separated, it can be predicted that the entire outer shape of the electronic component 21 is shifted in the lower right direction. Therefore, the relationship with the L-shaped marks 33 and 34 is seen. That is, from the prediction of the shift in the lower right direction, the inner side 33b of the vertical band portion 33b of the lower left L-shaped mark 33 is obtained.₁ And the inner side 34a of the horizontal band 34a of the L-shaped mark 34 on the upper right.₁ Find out if you are away from. In the case of FIG. Next, as a secondary determination, the lower side 21 a and the right side 21 d of the L-shaped marks 33 and 34 and the external shape of the electronic component 21, which are extremely strict relative to the connection pad 32, are horizontal to the lower left L-shaped mark 33. The outer side 33a of the band 33a₂ And the outer side 34b of the vertical strip 34b of the L-shaped mark 34 on the upper right.₂ Make sure that it does not protrude outside. That is, their outer side 33a₂ , 34b₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 4, since it can be confirmed that it is visible, it can be immediately determined that the deviation is within the allowable range. In this allowable mounting state, almost the entire solder pad 22 is bonded to the connection pad 32.
[0035]
FIG. 4 shows the case of the allowable mounting state shifted from the normal mounting state to the lower right direction. However, the outer sides of the L-shaped marks 33 and 34 may be shifted only in the right direction or only in the downward direction. Can be immediately determined that the deviation is within the allowable range.
[0036]
The case of FIG. 5 will be described. First, as a primary determination, all the outer sides 36a in relation to the L-shaped elongated strip marks 36, 37 having a length and a range almost comparable to the outer shape of the electronic component 21 are used.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. In the case of FIG. 5, it can be confirmed that it is accommodated at a glance. Therefore, it can be predicted that it is an allowable mounting state as a primary determination. At the same time, the inner side 36a of the lower right L-shaped strip-shaped mark 36₁ 36b₁ On the other hand, since the outer shapes (lower side 21a, right side 21d) of the electronic component 21 are separated, it can be predicted that the entire outer shape of the electronic component 21 is shifted in the upper left direction. Therefore, the relationship with the L-shaped marks 33 and 34 is seen. That is, from the prediction of the deviation in the upper left direction, the inner side 33a of the horizontal band 33a of the lower left L-shaped mark 33 is used.₁ And the inner side 34b of the vertical strip 34b of the L-shaped mark 34 on the upper right.₁ Find out if you are away from. In the case of FIG. Next, as a secondary determination, the upper side 21b and the left side 21c of the outer shapes of the L-shaped marks 33 and 34 and the electronic component 21 whose relative positional relationship with the connection pad 32 is very strict are horizontal to the upper right L-shaped mark 34. The outer side 34a of the band 34a₂ Or the outer side 33b of the vertical band 33b of the L-shaped mark 33 at the lower left₂ Make sure that it does not protrude outside. That is, their outer side 34a₂ 33b₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 5, since it can be confirmed that it is visible, it can be immediately determined that the deviation is within the allowable range. In this allowable mounting state, almost the entire solder pad 22 is bonded to the connection pad 32.
[0037]
FIG. 5 shows the case of the allowable mounting state shifted from the regular mounting state in the upper left direction. However, the outer sides of the L-shaped marks 33 and 34 are not affected even when shifted only in the left direction or only in the upward direction. If it is in a state where it is visible without being hidden by the electronic component, it can be immediately determined that the deviation is within an allowable range.
[0038]
6 to 9 show a case of mounting deviation exceeding the allowable range.
[0039]
In the case of FIG. 6, a state of mounting deviation confirmation when the electronic component 21 is excessively displaced upward is shown. First, as a primary determination, all the outer sides 36a in relation to the L-shaped elongated strip marks 36, 37 having a length and a range almost comparable to the outer shape of the electronic component 21 are used.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. In the case of FIG. 6, the outer side 37a of the horizontal elongated strip portion 37a of the L-shaped elongated strip mark 37 at the upper left at a glance.₂ Can be confirmed to be hidden by the upper side 21b of the electronic component 21 as indicated by a broken line. All other outer sides are visible. At the same time, the lower side 21a of the electronic component 21 is the inner side 36a of the horizontal elongated strip portion 36a of the L-shaped elongated strip mark 36 at the lower right.₁ And the inner side 33a of the horizontal band 33a of the L-shaped mark 33 at the lower left.₁ It can be confirmed that they are far apart. Therefore, as a primary determination, it can be intuitively predicted that the mounting deviation of the electronic component 21 is shifted upward beyond the allowable range. Next, as a secondary determination, the relationship between the upper right L-shaped mark 34 and the upper side 21b of the electronic component 21 that is extremely strict in the relative positional relationship with the connection pad 32 is seen from the prediction of the upward shift. That is, the upper side 21b of the electronic component 21 is the outer side 34a of the horizontal band 34a of the L-shaped mark 34 at the upper right.₂ Make sure that it does not protrude outside. That is, the outer side 34a₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 6, it is hidden and invisible. By this confirmation, it is possible to strictly determine that the electronic component 21 has caused a mounting deviation beyond the allowable range in the upward direction. Actually, the solder pad 22 is greatly displaced above the connection pad 32.
[0040]
In the case of FIG. 7, a mounting deviation confirmation state when the electronic component 21 has shifted too much downward is shown. First, as a primary determination, all the outer sides 36a in relation to the L-shaped elongated strip marks 36, 37 having a length and a range almost comparable to the outer shape of the electronic component 21 are used.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. In the case of FIG. 7, the outer side 36a of the horizontal elongated strip portion 36a of the L-shaped elongated strip mark 36 at the lower right at a glance.₂ Can be confirmed to be hidden by the lower side 21a of the electronic component 21 as indicated by a broken line. All other outer sides are visible. At the same time, the upper side 21b of the electronic component 21 is the inner side 37a of the horizontal elongated band portion 37a of the upper left L-shaped elongated band mark 37.₁ And the inner side 34a of the horizontal strip 34a of the L-shaped mark 34 at the upper right₁ It can be confirmed that they are far apart. Therefore, as a primary determination, it can be intuitively predicted that the mounting deviation of the electronic component 21 is shifted downward beyond the allowable range. Next, as a secondary determination, the relationship between the lower left L-shaped mark 33 and the lower side 21a of the electronic component 21 that is extremely strict in the relative positional relationship with the connection pad 32 is seen from the prediction of the downward shift. That is, the lower side 21 a of the electronic component 21 is the outer side 33 a of the horizontal band 33 a of the L-shaped mark 33 at the lower left.₂ Make sure that it does not protrude outside. That is, the outer side 33a₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 7, it is hidden and cannot be seen. By this confirmation, it can be strictly determined that the electronic component 21 has undergone mounting displacement beyond the allowable range in the lower direction. Actually, the solder pad 22 is greatly displaced below the connection pad 32.
[0041]
In the case of FIG. 8, a state of mounting deviation confirmation when the electronic component 21 is excessively shifted to the left side is shown. First, as a primary determination, all the outer sides 36a in relation to the L-shaped elongated strip marks 36, 37 having a length and a range almost comparable to the outer shape of the electronic component 21 are used.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. In the case of FIG. 8, the outer side 37b of the vertical elongated strip portion 37b of the L-shaped elongated strip mark 37 at the upper left at a glance.₂ Can be confirmed to be hidden by the portion of the left side 21c of the electronic component 21 as indicated by a broken line. All other outer sides are visible. At the same time, the right side 21d of the electronic component 21 is the inner side 36b of the vertical elongated strip portion 36b of the L-shaped elongated strip mark 36 at the lower right.₁ And the inner side 34b of the vertical strip 34b of the L-shaped mark 34 on the upper right.₁ It can be confirmed that they are far apart. Therefore, as a primary determination, it can be intuitively predicted that the mounting deviation of the electronic component 21 exceeds the allowable range and is shifted to the left side. Next, as a secondary determination, the relationship between the L-shaped mark 33 at the lower left and the left side 21c of the electronic component 21 that is extremely strict in the relative positional relationship with the connection pad 32 is seen from the prediction of the shift to the left side. That is, the portion of the left side 21 c of the electronic component 21 is the outer side 33 b of the vertical band portion 33 b of the lower left L-shaped mark 33.₂ Make sure that it does not protrude outside. That is, its outer side 33b₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 8, it is hidden and invisible. By this confirmation, it can be strictly determined that the electronic component 21 has a mounting deviation beyond the allowable range in the left direction. Actually, the solder pad 22 is significantly shifted to the left side from the connection pad 32.
[0042]
In the case of FIG. 9, the mounting deviation confirmation state when the electronic component 21 is shifted to the right side is shown. First, as a primary determination, all the outer sides 36a in relation to the L-shaped elongated strip marks 36, 37 having a length and a range almost comparable to the outer shape of the electronic component 21 are used.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. In the case of FIG. 9, the outer side 36b of the vertical elongated strip portion 36b of the L-shaped elongated strip mark 36 at the lower right at a glance.₂ Can be confirmed as being hidden by the portion of the right side 21d of the electronic component 21 as indicated by a broken line. All other outer sides are visible. At the same time, the left side 21c of the electronic component 21 is the inner side 37b of the vertical elongated strip portion 37b of the L-shaped elongated strip-shaped mark 37 in the upper left.₁ And the inner side 33b of the vertical band 33b of the lower left L-shaped mark 33₁ It can be confirmed that they are far apart. Therefore, as a primary determination, it can be intuitively predicted that the mounting deviation of the electronic component 21 exceeds the allowable range and is shifted to the right side. Next, as a secondary determination, the relationship between the upper right L-shaped mark 34 and the right side 21d of the electronic component 21 that is extremely strict in the relative positional relationship with the connection pad 32 is seen from the prediction of the shift to the right side. That is, the portion of the right side 21d of the electronic component 21 is the outer side 34b of the vertical belt portion 34b of the upper right L-shaped mark 34.₂ Make sure that it does not protrude outside. That is, its outer side 34b₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 9, it is hidden and cannot be seen. By this confirmation, it can be strictly determined that the electronic component 21 has a mounting deviation in the right direction beyond the allowable range. Actually, the solder pad 22 is significantly shifted to the right side from the connection pad 32.
[0043]
The confirmation of the mounting displacement in the oblique direction can be made by a combination of any two of FIGS. 6, 7, 8, and 9. In short, first, in relation to the L-shaped elongated strip-shaped marks 36 and 37 having a length and range substantially comparable to the outer shape of the electronic component 21, all of the outer sides 36a thereof are used.₂ 36b₂ 37a₂ 37b₂ It is determined whether the mounting deviation within the allowable range is a mounting deviation exceeding the allowable range by checking whether or not the outer shape of the electronic component 21 is accommodated inside, and then the connection pad 32 Whether or not the mounting deviation within the allowable range exceeds the allowable range depending on whether or not the outer sides of the L-shaped marks 33 and 34 with the strict relative positional relationship are covered with the electronic parts. Is strictly determined secondary.
[0044]
4 and 5, the entire outer side 33a of the mounting misalignment confirmation mark formed by the two L-shaped marks 33, 34 and the two L-shaped elongated strip marks 36, 37.₂ 33b₂ , 34a₂ , 34b₂ 36a₂ 36b₂ 37a₂ 37b₂ Since the outer shape of the electronic component 21 is accommodated in all of the above, the primary determination and the secondary determination are performed almost simultaneously.
[0045]
10 and 11 show a state in which the two L-shaped strip-shaped marks 36 and 37 by silk screen printing are slightly deviated relative to the connection pad 32 and thus relative to the two L-shaped marks 33 and 34. The state of mounting deviation confirmation when printed is shown. The case where the L-shaped elongated strip marks 36 and 37 are shifted to the upper left is illustrated.
[0046]
In the case of FIG. 10, at a glance, the entire outer side 33a of the mounting misalignment confirmation mark formed by the two L-shaped marks 33, 34 and the two L-shaped elongated strip marks 36, 37.₂ 33b₂ , 34a₂ , 34b₂ 36a₂ 36b₂ 37a₂ 37b₂ Since the outer shape of the electronic component 21 is completely accommodated in all of the above, it can be strictly determined that the mounting deviation is within the allowable range. That is, the primary determination and the secondary determination can be performed simultaneously.
[0047]
In the case of FIG. 11, first, as a primary determination, all the outer sides 36 a in relation to the L-shaped strip-shaped marks 36 and 37 having a length and a range almost comparable to the outer shape of the electronic component 21.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. The outer side 37b of the vertical elongated strip portion 37b of the upper left L-shaped elongated strip-shaped mark 37 at a glance.₂ Can be confirmed to be hidden by the portion of the left side 21c of the electronic component 21 as indicated by a broken line. All other outer sides are visible. At the same time, the right side 21d of the electronic component 21 is the inner side 36b of the vertical elongated strip portion 36b of the L-shaped elongated strip mark 36 at the lower right.₁ And the inner side 34b of the vertical strip 34b of the L-shaped mark 34 on the upper right.₁ It can be confirmed that they are far apart. Therefore, as a primary determination, it can be intuitively predicted that the mounting deviation of the electronic component 21 exceeds the allowable range and is shifted to the left side. Next, as a secondary determination, the relationship between the L-shaped mark 33 at the lower left and the left side 21c of the electronic component 21 that is extremely strict in the relative positional relationship with the connection pad 32 is seen from the prediction of the shift to the left side. That is, the portion of the left side 21 c of the electronic component 21 is the outer side 33 b of the vertical band portion 33 b of the lower left L-shaped mark 33.₂ Make sure that it does not protrude outside. That is, its outer side 33b₂ Is visible without being hidden by the electronic component 21. Further, the lower side 21a of the electronic component 21 is the inner side 36a of the horizontal elongated strip portion 36a of the L-shaped elongated strip mark 36 at the lower right.₁ Therefore, the relationship between the upper right L-shaped mark 34 and the upper side 21b of the electronic component 21 is seen. That is, the upper side 21b of the electronic component 21 is the outer side 34a of the horizontal band 34a of the L-shaped mark 34 at the upper right.₂ Make sure that it does not protrude outside. That is, the outer side 34a₂ Is visible without being hidden by the electronic component 21. In the case of FIG. 11, both are hidden and cannot be seen. By this confirmation, it is possible to strictly determine that the electronic component 21 has a mounting deviation exceeding the allowable range in the left direction and the upper direction. Actually, the solder pad 22 is greatly shifted to the upper left side from the connection pad 32.
[0048]
In the case of FIG. 12, first, as a primary determination, all the outer sides 36 a in relation to the L-shaped elongated strip marks 36 and 37 having a length and a range almost comparable to the outer shape of the electronic component 21.₂ 36b₂ 37a₂ 37b₂ It is confirmed whether or not the outer shape of the electronic component 21 is housed inside. The outer side 36a of the horizontal elongated strip 36a of the L-shaped elongated strip mark 36 at the lower right at a glance.₂ And the outer side 36b of the vertical elongated strip 36b.₂ Can be confirmed to be hidden by the lower side 21a and the right side 21d of the electronic component 21 as indicated by a broken line. All other outer sides are visible. In this case, as a primary determination, it can be intuitively predicted that the mounting deviation of the electronic component 21 is shifted to the lower right side beyond the allowable range. Next, as a secondary determination, based on the prediction of the shift to the lower right side, the relationship between the lower left L-shaped mark 33 and the lower side 21a of the electronic component 21 and the upper right side of the electronic component 21 and the upper right side are extremely strict. The relationship between the L-shaped mark 34 and the right side 21d of the electronic component 21 is seen. That is, the lower side 21 a of the electronic component 21 is the outer side 33 a of the horizontal band 33 a of the L-shaped mark 33 at the lower left.₂ Make sure that it does not protrude outside. That is, the outer side 33a₂ Is visible without being hidden by the electronic component 21. It can be confirmed that it is not hidden. The right side 21d of the electronic component 21 is the outer side 34b of the vertical band 34b of the L-shaped mark 34 on the upper right.₂ Make sure that it does not protrude outside. That is, its outer side 34b₂ Is visible without being hidden by the electronic component 21. It can be confirmed that it is not hidden. By this confirmation, it can be strictly determined that the electronic component 21 is in the allowable mounting state.
[0049]
FIG. 13 is a plan view showing a printed wiring board according to another embodiment. Simultaneously with the step of forming the plurality of connection pads 32 on the printed wiring board 31, the L-shaped marks 33, 34, 39 are formed corresponding to the three corner vertices of the electronic component 21 with the same material copper as the connection pads 32. In addition, an arcuate mark 40 is also formed corresponding to the cut surface 23 of the electronic component 21. On the solder resist 35, four linear strip-like marks 41, 42, 43, 44 are formed by silk screen printing. Between the straight strip-shaped marks 41, 42, 43, 44 and the L-shaped marks 33, 34, 39 and the arcuate mark 40, gaps 45a to 45h having required dimensions are secured. This embodiment can also exhibit the same function as described above.
[0050]
The gaps 38a to 38d may be omitted in the embodiment shown in FIG. 3, or the gaps 45a to 45h may be omitted in the embodiment shown in FIG. The L-shaped marks 33, 34, 39 and the bow-shaped mark 40 are visually distinguished from the L-shaped elongated strip-shaped marks 36, 37 and the straight elongated strip-shaped marks 41, 42, 43, 44 that are silk-screen printed. Therefore, it is preferable to provide a gap between them. The width of the strip-shaped mark formed by silk screen printing may be larger than the width of the mark formed by copper.
[0051]
In the above-described embodiment, the mounting deviation confirmation marks 33 and 34 as the component outline display body are L-shaped continuous shapes, but are not limited to this, and are partially cut. It may be a part, and may be partially curved or waveform.
[0052]
In the above-described embodiment, the mounting misalignment auxiliary confirmation marks 36 and 37 as the component outer shape display body are L-shaped continuous shapes, but are not limited thereto, and are partially cut. It may be a partial shape, and may be partially curved or wavy.
[0053]
In the above-described embodiment, the wiring pattern is the connection pad 32. However, the wiring pattern is not limited to this, and any wiring pattern capable of mounting an electronic component may be used.
[0054]
In the above-described embodiment, there are a plurality of connection pads 32. However, the number of connection pads 32 is not limited to this, and may be one.
[0055]
In the above-described embodiment, the shape of the solder pad 22 and the connection pad 32 is a circle in plan view. However, the shape is not limited to this, and may be an elliptical shape or other shapes.
[0056]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
[0057]
According to the first aspect of the present invention, in a printed wiring board having a wiring pattern for mounting an electronic component on a component mounting surface, a shape corresponding at least partially to the outer shape of the electronic component mounted on the component mounting surface And a component outline display body at least a part of which corresponds to the position of the wiring pattern, and the component outline display body has the electronic component mounted in the mounting position. Since it is configured so that the presence or absence of the component mounting deviation can be confirmed from the outside, the mounting position deviation of the electronic component mounted by the component outline display can be easily confirmed from the outside. In this case, since the component outline display has a shape corresponding at least partially to the outline of the electronic component, it is easy to check the mounting position deviation, and at least a part of the component outline display is a wiring pattern. Therefore, the accuracy of checking the mounting position deviation is high.
[0058]
The component outer shape display body has a mounting deviation confirmation mark made of the same conductive material as the wiring pattern in a position substantially coincident with at least one corner vertex of the outer shape of the electronic component in a regular mounting state, Since the mark is provided in a predetermined shape that partially matches the outer shape of the corner of the electronic component,, RealThe accuracy of checking the mounting position deviation is high.
[0059]
The component outer shape display body further has a mark for assisting mounting deviation confirmation of a non-conductive material in a position substantially corresponding to any side of the outer shape of the electronic component in a regular mounting state, and the mark has a predetermined width. In addition, since it is formed with a predetermined length, in the confirmation of the presence or absence of mounting displacement after mounting the electronic component, first, as a primary determination, the relationship with the mounting displacement confirmation assisting mark corresponding to the side of the electronic component In this case, it is confirmed whether or not the external shape of the electronic component is accommodated inside the mounting deviation confirmation assisting mark, and if it is, it is predicted that it is in an allowable mounting state. It is predicted that it may have been mounted, and this prediction is used for secondary determination. As a secondary determination, look at the relationship between the mounting displacement confirmation mark with high positional relationship with the wiring pattern and the external shape of the electronic component, and check whether the mounting displacement confirmation mark is hidden by the electronic component. When the mounting deviation confirmation mark is not hidden, it is determined that the mounting state is acceptable, and when the mounting deviation confirmation mark is hidden, it is determined that the mounting state exceeds the allowable range. The mounting misalignment confirmation mark with a high positional relationship with the pattern has a predetermined shape that matches the external shape of the component, which makes it possible to determine whether the side of the electronic component is visible or hidden. Unlike the case of point marks, the accuracy of mounting deviation confirmation can be made extremely high, and the mounting deviation confirmation auxiliary mark has a predetermined length, so that the primary determination is very easy. Since the primary judgment is the reference in the case of a secondary judgment, it is possible to significantly up the work of the confirmation.
[Brief description of the drawings]
FIG. 1 is a bottom view and a front view of an electronic component mounted on a printed wiring board according to an embodiment of the present invention.
FIG. 2 is a plan view showing a printed wiring board according to an embodiment of the present invention.
FIG. 3 is a plan view of an entire state in which electronic components are mounted on a printed wiring board and a plan view of an enlarged portion in the embodiment.
FIG. 4 is a plan view of a regular mounting state when the electronic component is shifted to the lower right in the embodiment.
FIG. 5 is a plan view of a regular mounting state when the electronic component is shifted to the upper left in the embodiment.
FIG. 6 is a plan view of a mounted state in which an electronic component is displaced above an allowable range in the embodiment.
FIG. 7 is a plan view of a mounted state in which an electronic component is shifted below an allowable range in the embodiment;
FIG. 8 is a plan view of a mounting state in which an electronic component is shifted to the left beyond an allowable range in the embodiment.
FIG. 9 is a plan view of a mounting state in which an electronic component is shifted to the right beyond an allowable range in the embodiment.
FIG. 10 is a plan view showing a printed wiring board according to an embodiment in a case where two L-shaped elongated strip-shaped marks are formed slightly deviated from the L-shaped mark, and showing a normal mounting state;
11 is a plan view of a mounting state in which the electronic component is shifted to the left beyond the allowable range in the case of FIG. 10 described above.
12 is a plan view of a regular mounting state when the electronic component is shifted to the lower right in the case of FIG.
FIG. 13 is a plan view of a printed wiring board according to another embodiment.
FIG. 14 is a plan view showing a relationship between a printed wiring board on which a square annular mounting displacement confirmation pattern is formed by silk screen printing and an electronic component.
15 is a plan view showing a mounting state of electronic components on the printed wiring board in the case of FIG.
FIG. 16 is a plan view of a printed wiring board on which dot marks and line marks are formed in the case of the prior art described in JP-A-9-83093.
17 is a schematic plan view showing a state of mounting deviation confirmation centered on the dotted mark in the case of FIG.
18 is a schematic plan view showing a state of deviation of a linear mark from a dotted mark in the case of FIG.
[Explanation of symbols]
21 …… Electronic components
22 …… Solder pads
31 …… Printed circuit board
32 …… Connection pad
33 …… L-shaped mark for confirming mounting deviation at the lower left
34 …… L-shaped mark for checking mounting deviation in the upper right
35 …… Solder resist
35a ... chipped portion of solder resist
36 …… L-shaped strip-shaped mark for assisting in confirming mounting deviation in the lower right
37 …… L-shaped elongated strip mark for assisting in confirming mounting deviation in the upper left
21a: Lower side of electronic component
21b ... Upper side of electronic component
21c ... Left side of electronic component
21d: right side of electronic component
21e₁ ~ 21e_Five …… Corner apex of electronic parts
33a, 34a ...... Horizontal band
33b, 34b ... vertical belt
36a, 37a ...... Horizontal strip
36b, 37b ...... Vertical elongated strip
33c, 34c …… Inner corner vertex
33a₁ 33b₁ , 34a₁ , 34b₁ ...... Inner side
36a₁ 36b₁ 37a₁ 37b₁ ...... Inner side
33a₂ 33b₂ , 34a₂ , 34b₂ ...... Outside side
36a₂ 36b₂ 37a₂ 37b₂ ...... Outside side
39 …… L-shaped mark for checking mounting deviation
40 …… A bow mark for checking mounting deviation
41 to 44 ...... Linear strip mark for assisting in confirming mounting displacement

Claims (1)

In a printed wiring board equipped with a wiring pattern for mounting electronic components on the component mounting surface,
A component outer shape display body having a shape corresponding at least partially to the outer shape of the electronic component mounted on the component mounting surface, and at least a portion of the position corresponding to the position of the wiring pattern; The component outer shape display body is configured so that the electronic component can be confirmed from the outside with or without mounting deviation in a state where the electronic component is mounted at the mounting position .
The component outer shape display body has a mounting deviation confirmation mark made of the same conductive material as the wiring pattern in a position substantially coincident with at least one corner vertex of the outer shape of the electronic component in a regular mounting state, The mounting deviation confirmation mark is provided in a predetermined shape that partially matches the outer shape of the corner of the electronic component, and is positioned on any side of the outer shape of the electronic component in a regular mounting state. A printed wiring board comprising: a mounting displacement confirmation assisting mark made of a non-conductive material substantially correspondingly, wherein the mounting displacement confirmation assisting mark is formed with a predetermined width and a predetermined length .

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