JP2006278946A - Package substrate and image pickup apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To monitor a soldering state or to efficiently utilize the monitoring information of the soldering state without increasing the size of a package substrate. <P>SOLUTION: Bump lands 54 (solder balls 60) of the package substrate form a substantially square shape as a whole, and are arranged in a lattice. The bump lands 54 at four corners of the outermost periphery are coupled in series by a coupling pattern 180. In this configuration, a predetermined test signal outputted from a signal circuit is inputted into a bump land 54A on one corner out of the serially coupled bump lands, and the test signal is outputted from a bump land 54B of the other corner via the coupling pattern 180. A determining circuit determines whether or not a crack is generates in the solder junction of the bump lands 54 at the four corners to cause a failure in soldering on the basis of the input test signal. Then, an output circuit outputs the result of the determination. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a package substrate, a semiconductor circuit device on which the package substrate is mounted, and an imaging device.

In recent years, with the increase in density and size of electronic devices such as mobile phones and personal computers, there is an increasing demand for higher density and size reduction of package substrates. Corresponding to the higher density and smaller size of the package substrate, solder balls are arranged in a grid on the lower surface, which can handle more terminals than the conventional QFP (Quad Flat Package) type. BGA (Ball Grid Array) substrates have become mainstream. The BGA board is soldered and mounted on the printed circuit board with the solder balls on the lower surface. After soldering, even if defects such as disconnection or cracks occur in the soldered part due to warpage of the BGA board, It is difficult to find by visual inspection or appearance inspection in the manufacturing process.

  Also, if a defect occurs in the soldered part after shipping as a product, it is necessary to identify the defective part while checking the various parts through the circuit from the failure symptom. Was spending. In addition, it is difficult to accurately identify the defective part.

  Furthermore, in order to repair, it is necessary to heat and remove the entire component. At this time, even if there is a disconnection or the like in the soldering of the adjacent component, the heating may recover and misjudgment.

Therefore, a method has been proposed in which a wiring pattern connecting the innermost circumference and the outermost circumference between the BGAs of the BGA substrate is formed, the resistance value between them is measured, and the quality of soldering due to the warpage of the substrate is monitored. Yes. (For example, refer to Patent Document 1).
JP 2002-76187 A

  However, the method described in Japanese Patent Laid-Open No. 2002-76187 is a wiring pattern in which all the innermost and outermost electrodes are connected, so that the innermost and outermost electrodes are all in a soldered state. Used for monitoring. For this reason, there was a first problem that the package substrate becomes larger than necessary.

  In addition, there is a second problem that the information for monitoring the soldering state is used only for the purpose of warning the user and is not sufficiently effectively utilized.

  The present invention has been made to solve the above problem, and aims to solve at least one of the first problem and the second problem.

  In order to achieve the above object, a package substrate according to claim 1 is a package substrate in which a semiconductor chip is mounted on an upper surface, a plurality of electrodes are provided on a lower surface, and the electrodes are soldered and mounted on a printed circuit board. And a signal generating means for outputting an inspection signal capable of inspecting the quality of soldering between the electrodes and the printed circuit board, wherein the plurality of electrodes on the outermost periphery are arranged in a substantially rectangular shape, and are arranged in the substantially rectangular shape. Of the outermost electrodes, at least one of the electrodes located at the four corners is an inspection signal output electrode for outputting an inspection signal from the signal generating means.

  In the package substrate according to the first aspect, the semiconductor chip is mounted on the upper surface, and a plurality of electrodes on the lower surface are soldered and mounted on the printed circuit board. The outermost peripheries of the plurality of electrodes are arranged in a substantially square shape.

  And the inspection signal output electrode which outputs the inspection signal which can test | inspect the quality of the soldering of an electrode and a printed circuit board at least 1 or more of the electrodes located in four corners among the electrodes of the outermost periphery arranged in the substantially square shape It is said. Therefore, the state of soldering (good or bad) can be monitored without increasing the size of the package substrate.

  According to a second aspect of the present invention, there is provided the semiconductor circuit device according to the first aspect, the printed circuit board on which the package substrate is mounted by soldering, the inspection signal is input, and the electrode is based on the input inspection signal. And a judgment means for judging whether the soldering with the printed circuit board is good or not, and an output means for outputting a judgment result of the judgment means.

  According to another aspect of the semiconductor circuit device of the present invention, at least one of the electrodes located at the four corners of the outermost electrodes arranged in a substantially square shape on the package substrate is used as an inspection signal output electrode, and the electrode and the printed circuit board are soldered. An inspection signal capable of inspecting the quality of the output is output.

  The determination means determines whether or not the electrode and the printed circuit board are soldered based on the input inspection signal. And an output means outputs a judgment result, for example, displays on the display apparatus in a manufacturing process, and can test | inspect the quality of soldering with a printed circuit board.

  Since only the electrodes located at the four corners of the package substrate are used as inspection signal output electrodes, the state of the soldered portion can be monitored without increasing the size of the package substrate.

  According to a third aspect of the present invention, there is provided the semiconductor circuit device according to the second aspect, wherein at least two of the electrodes positioned at the four corners including the inspection signal output electrode are connected in series with a connection pattern, and connected. It is characterized in that at least one of the electrodes other than the inspection signal output electrode is used as an inspection signal input electrode for inputting the inspection signal to the determination means.

  According to a third aspect of the present invention, at least two of the electrodes located at the four corners are connected in series with a connection pattern. At least one of the connected electrodes other than the inspection signal output electrode is used as an inspection signal input electrode for inputting the inspection signal to the determination means. Therefore, it can be judged whether the soldering of the electrodes at the four corners connected by the connection pattern is good.

  According to a fourth aspect of the present invention, there is provided the semiconductor circuit device according to the second or third aspect, wherein the determination means is provided on the package substrate.

  In the semiconductor circuit device according to the fourth aspect, since the judging means is provided on the package substrate, the semiconductor circuit device is downsized.

  An imaging device according to a fifth aspect includes the semiconductor circuit device according to any one of the second to fourth aspects.

  Since the imaging device according to claim 5 includes the semiconductor circuit device according to any one of claims 2 to 4, the state of soldering can be monitored.

  According to a sixth aspect of the present invention, there is provided the imaging device according to the fifth aspect, further comprising display means for displaying a warning based on the determination result output from the output means.

  The imaging apparatus according to claim 6 displays a warning on the display unit based on the determination result output from the output unit. Therefore, the state of soldering can be easily monitored.

  According to a seventh aspect of the present invention, in the configuration of the fifth or sixth aspect, the imaging device further includes a storage unit that stores the determination result output from the output unit.

  In the imaging device according to the seventh aspect, the determination result output from the output unit is stored in the storage unit. Therefore, the field data monitoring the soldering state can be obtained by reading the determination result stored in the storage means of the imaging device collected from the market. That is, the judgment result (monitoring state monitoring information) is effectively used.

  An imaging apparatus according to an eighth aspect of the invention is characterized in that, in the configuration according to the seventh aspect, the storage means also stores log data of a usage status of the imaging apparatus.

  In the image pickup apparatus according to the eighth aspect, the storage unit also stores log data of a usage status of the image pickup apparatus. Therefore, by reading out the judgment result and the usage status from the storage means of the product collected from the market, more useful field data can be obtained in which the soldering status corresponding to the usage status is monitored.

  The imaging apparatus according to claim 9, wherein a semiconductor substrate is mounted on an upper surface, a package substrate having a plurality of electrodes on a lower surface, and a printed circuit board on which the electrode of the package substrate is soldered and the package substrate is mounted And a signal generating means for outputting an inspection signal capable of inspecting whether the electrode and the printed circuit board are soldered to any of the electrodes of the package substrate, and the inspection signal is input and input Based on the signal, determination means for determining whether the electrode and the printed circuit board are soldered, output means for outputting the determination result of the determination means, and storage means for storing the determination result output from the output means It is characterized by providing these.

  In the image pickup apparatus according to the ninth aspect, the signal generation unit outputs an inspection signal capable of inspecting whether the soldering between the electrode and the printed circuit board is good or not to any of the electrodes of the package substrate. An inspection signal is input, and based on the input inspection signal, the determination unit determines whether or not the soldering between the electrode and the printed circuit board is good. The output means outputs the determination result of the determination means. Then, the storage means stores the determination result output from the output means.

  Therefore, the field data monitoring the soldering state can be obtained by reading the determination result stored in the storage means of the imaging device collected from the market. That is, the judgment result (monitoring state monitoring information) is effectively used.

  According to a tenth aspect of the present invention, in the configuration according to the ninth aspect, the storage unit also stores log data of a usage status of the imaging device.

  In the image pickup apparatus according to a tenth aspect, the storage unit also stores log data of the usage status of the image pickup apparatus. Therefore, by reading out the judgment result and the usage status from the storage means of the product collected from the market, more useful field data can be obtained in which the soldering status corresponding to the usage status is monitored.

  An image pickup apparatus according to an eleventh aspect is characterized in that, in the configuration according to the ninth or tenth aspect, the image pickup apparatus further comprises display means for displaying a warning based on the determination result outputted from the output means.

  The imaging apparatus according to an eleventh aspect displays a warning on the display unit based on the determination result output from the output unit. Therefore, the state of soldering can be easily monitored.

  As described above, the present invention is an inspection signal capable of inspecting at least one of the electrodes located at the four corners of the outermost peripheral electrodes arranged in a substantially rectangular shape for the quality of soldering between the electrodes and the printed circuit board. Can be monitored without increasing the size of the package substrate, or the determination result of the soldering state can be stored in the storage means and read out to determine the determination result. (Soldering status monitoring information) is used effectively.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, an external configuration of the digital camera 10 according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, the digital camera 10 shoots a lens 21 for forming a subject image on the front surface of the camera housing 11, a strobe 62 that emits light to irradiate the subject as necessary during photographing, and photographing. A finder 88 used to determine the composition of the subject is provided. In addition, the digital camera 10 includes a release button (so-called shutter) 92 and a power switch 94 that are pressed by the user when shooting is performed on the upper surface of the camera housing 11.

  Note that the release button 92 of the digital camera 10 according to the present embodiment is pressed down to an intermediate position (hereinafter referred to as “half-pressed state S1”), and pressed to a final pressed position that exceeds the intermediate position. 2 states (hereinafter referred to as “fully pressed state S2”) can be detected. In the digital camera 10, when the release button 92 is half-pressed in the state S1, an AE (Automatic Explosure, meaning automatic exposure) function works and the exposure state (shutter speed, aperture state) is changed. After the setting, the AF (abbreviation of Auto Focus, meaning automatic focusing) function is operated and focusing control is performed, and then exposure (photographing) is performed when the shutter button is fully pressed S2. Yes.

  On the other hand, the eyepiece of the finder 88 is provided on the back of the camera housing 11. In the vicinity of the eyepiece portion of the finder 88 (downward in FIG. 1), a liquid crystal display 44 (hereinafter referred to as “hereinafter,“ a subject image, various menu screens, messages, etc.) indicated by digital image data obtained by photographing. LCD 44 "). Further, a mode change switch 96 is provided near the LCD 44 (upward in FIG. 1), and a cross cursor button 98 is provided near the LCD 44 (right side in FIG. 1). The mode switch 96 is either a shooting mode that is a mode for performing shooting by a slide operation by a user or a playback mode that is a mode for displaying (reproducing) a subject image indicated by digital image data obtained by shooting. It is for setting to one of these modes. The cross cursor button 98 is a total of five keys including four arrow keys indicating the upward, downward, left, and right movement directions in the display area of the LCD 44 and a determination key positioned at the center of the four arrow keys. The corresponding command is output when each key is pressed. In addition, in the vicinity of the cross cursor button 98 (upward in FIG. 1), a forced light emission switch 99 for setting a forced light emission mode, which is a mode in which the strobe 62 is forced to emit light at the time of shooting, is provided by a user pressing operation. It has been.

  Next, the configuration of the electrical system of the digital camera 10 according to the present embodiment will be described with reference to FIG.

  The digital camera 10 includes a camera module 12. The camera module 12 includes an optical unit 22 configured to include a lens 21, and a charge coupled device 24 (hereinafter referred to as “CCD 24”) is provided behind the optical axis of the lens 21 on the exit side of the optical unit 22. It has been. The CCD 24 is connected to the system bus BUS via an analog signal processing unit 26, an analog / digital converter 28 (hereinafter referred to as “ADC 28”), and a digital signal processing unit 30. The analog signal processing unit 26 is configured to include a circuit that obtains accurate pixel data by reducing noise (particularly thermal noise) included in the output signal of the CCD. The ADC 28 is for converting an input analog signal into digital data. The digital signal processing unit 30 has a built-in line buffer having a predetermined capacity, and performs control for directly storing the input digital image data in a predetermined area of the memory 72, and various digital images are applied to the digital image data. The processing is performed.

  Note that the digital signal processing unit 30, the LCD interface 42, the CPU (central processing unit) 50, the memory interfaces 70 and 170, the external memory interface 80, and the compression / decompression processing circuit 86 are mutually connected to the system bus BUS. It is connected to be able to send and receive commands. The LCD interface 42 is an interface circuit that generates a signal for causing the LCD 44 to display an image or a menu screen indicated by the digital image data and supplies the signal to the LCD 44. A CPU (Central Processing Unit) 50 is a processing unit that controls the operation of the entire digital camera 10. The memory 72 is a memory constituted by a VRAM (Video RAM) that mainly stores digital image data obtained by photographing. The memory 172 is a non-volatile memory that mainly stores various information and data. The memory interfaces 70 and 170 are control circuits for accessing the memories 72 and 172. The external memory interface 80 is an interface circuit for enabling the digital camera 10 to access a memory card 82 formed of a recording medium such as smart media (Smart Media (registered trademark)). The compression / decompression processing circuit 86 is a processing circuit that performs compression processing on digital image data in a predetermined compression format, and performs decompression processing on the compressed digital image data according to the compression format.

  Therefore, the CPU 50 controls the operation of the digital signal processing unit 30 and the compression / decompression processing circuit 86, displays various information via the LCD interface 42 to the LCD 44, and the memory interfaces 70, 170 to the memories 72, 172 and the memory card 82. And access via the external memory interface 80.

  On the other hand, the digital camera 10 includes a timing generator 32 that mainly generates a timing signal for driving the CCD 24 and supplies the timing signal to the CCD 24, and the driving of the CCD 24 is controlled by the CPU 50 via the timing generator 32.

  The digital camera 10 also includes a drive unit 34, and the driving of the focus adjustment mechanism (details will be described later), the zoom mechanism, and the aperture drive mechanism provided in the optical unit 22 is also controlled by the CPU 50 via the drive unit 34. .

  When changing the optical zoom magnification, the CPU 50 drives and controls a zoom mechanism (not shown) to change the focal length of the lens 21 included in the optical unit 22. Further, the CPU 50 performs focus control by driving and controlling the focus adjustment mechanism (described later) so that the contrast value of the image obtained by imaging by the CCD 24 is maximized. The digital camera 10 according to the present embodiment employs a so-called TTL (Through The Lens) method in which the lens position is set so that the contrast of the read image is maximized as the focus control.

  Further, the release button 92, the power switch 94, the mode change switch 96, the cross cursor button 98, and various buttons and switches (generally referred to as “operation unit 90” in the figure) of the forced light emission switch 99 are connected to the CPU 50. Thus, the CPU 50 can always grasp the operation state of the operation unit 90.

  In addition, the digital camera 10 includes a charging unit 160 that is interposed between the strobe 62 and the CPU 50 and charges power for causing the strobe 62 to emit light under the control of the CPU 50. The strobe 62 is also connected to the CPU 50, and the light emission of the strobe 62 is controlled by the CPU 50.

  Next, the overall operation of the digital camera 10 according to the present embodiment will be briefly described.

  First, an image is picked up by the CCD 24 through the optical unit 22, and R (red), G (green), and B (blue) signals indicating the subject image are sequentially output to the analog signal processing unit 26. The analog signal processing unit 26 performs analog signal processing such as correlated double sampling processing on the signal input from the CCD 24 and then sequentially outputs the signal to the ADC 28. The ADC 28 converts the R, G, and B signals input from the analog signal processing unit 26 into 12-bit R, G, and B signals (digital image data) and sequentially outputs the signals to the digital signal processing unit 30. The digital signal processing unit 30 accumulates digital image data sequentially output from the ADC 28 in a built-in line buffer and temporarily stores it in a predetermined area of the memory 72.

  Digital image data stored in a predetermined area of the memory 72 is read out by the digital signal processing unit 30 under the control of the CPU 50, and a white balance is adjusted by applying a digital gain corresponding to a predetermined physical quantity to the gamma data. Processing and sharpness processing are performed to generate 8-bit digital image data, and further YC signal processing is performed to generate a luminance signal Y and chroma signals Cr and Cb (hereinafter referred to as “YC signal”), and a YC signal is generated. The data is stored in an area different from the predetermined area in the memory 72.

  The LCD 44 is configured to display a moving image (through image) obtained by continuous imaging by the CCD 24 and can be used as a finder. However, when the LCD 44 is used as a finder, The generated YC signal is sequentially output to the LCD 44 via the LCD interface 42. As a result, a through image is displayed on the LCD 44.

  Here, when the release button 92 is half-pressed by the user, after the AE function is activated and the exposure state is set as described above, the AF function is activated and focus control is performed, and then the fully-pressed state is continued. In this case, the YC signal stored in the memory 72 at this time is compressed in a predetermined compression format (JPEG format in the present embodiment) by the compression / decompression processing circuit 86 and then passed through the external memory interface 80. Shooting is performed by recording in the memory card 82.

  Next, the camera module 12 will be described.

  As shown in FIG. 3, the camera module 12 includes an optical unit 22, and a CCD 24 is provided behind the optical axis of the lens 21 on the exit side of the optical unit 22. The CCD 24 is soldered to the printed wiring board 13. Also, a BGA package 51 on which a semiconductor chip 57 (IC chip, see FIG. 4, details will be described later) and a BGA package 151, 251 on which a semiconductor chip is similarly mounted are mounted on a printed circuit board 52. 300. The printed wiring board 13 and the printed board 52 of the board 300 are electrically connected by the flexible printed wiring board 16. The connector 18 connected to the connector 17 connected to the system bus BUS (see FIG. 2) is soldered to the printed wiring board 19, and the printed circuit board 52 and the printed wiring board 19 are connected by the flexible printed wiring board 40. It is connected. The direction in which the printed wiring board 19 is connected to the connector 17 (the direction of arrow A in the figure) is substantially perpendicular to the printed wiring board 13 and the printed board 52, and the flexible printed wiring board 40 is substantially bent at the bent portion 40Z. It is bent at a right angle.

  Next, details of the BGA packages 51, 151, and 251 described above and mounting of the BGA packages 51, 151, and 251 on the printed circuit board 52 will be described. Since the details and mounting of the BGA packages 51, 151, and 251 are the same, the BGA package 51 will be described as a representative.

  4 is a schematic cross-sectional view showing a state before mounting, and FIG. 5 is a schematic cross-sectional view showing a state after mounting. In the BGA package 51, a plurality of bump lands 54 are formed on the upper and lower surfaces of the substrate 53, and the bump lands 54 are connected to each other by a signal via hole 55 and a thermal via 56 that vertically penetrate the substrate 53. It is in a state. Then, a semiconductor chip (IC chip) 57 is mounted on the upper surface side, the semiconductor chip 57 and the bump land 54 are electrically connected by a bonding wire 58, and a substantially entire upper surface side is further formed by a mold resin 59. It is in a sealed state.

  The semiconductor chip (IC chip) 57 receives the analog signal processing unit 26, the ADC 28, the signal circuit 102 that outputs a predetermined inspection signal, and the detected inspection signal that has been input and detected. The determination circuit 104 (see FIG. 2) and the like are built in. Details of the inspection signal output from the signal circuit 102 and the determination by the determination circuit 104 will be described later.

  On the other hand, a plurality of lands 61 are formed on the upper and lower surfaces of the printed circuit board 52 by printing. The land 61 on the upper surface corresponds to the bump land 54 formed on the substrate 53 of the package substrate 51.

  Then, solder balls are formed in advance on the bump lands 54 formed on the substrate 53 of the BGA package 51 and soldered to the lands 61 formed on the upper surface of the printed substrate 52, so that the package substrate 51 is attached to the printed substrate 52. Is implemented.

  Further, as shown in FIGS. 6 and 8, in the substrate 300, the bump lands 54 (solder balls 60) of the package substrate 51 are arranged in a lattice having a substantially rectangular shape as a whole. The bump lands 54 at the four corners on the outermost periphery are connected in series by a connection pattern 180. Then, the predetermined inspection signal output from the signal circuit 102 is output to the bump land 54A at one end connected in series, and the inspection signal is determined from the bump land 54B at the other end via the connection pattern 180. It is the composition which inputs to. 8 is a bottom view as viewed from below in FIGS. 4 and 6, and the bottom is a top view as viewed from above.

  The connection pattern 180 may be other than the above. For example, although not shown, only two or three of the bump lands 54 at the outermost four corners may be connected by the connecting pattern 180. Alternatively, as shown in FIG. 9, two bump lands 54 at the outermost four corners may be connected in series by connecting patterns 182 and 184. In this case, there are two bump lands 54A to which a predetermined inspection signal output from the signal circuit 102 is output and two bump lands 54B to which the inspection signal is input.

  As shown in FIG. 6, the BGA packages 151 and 251 also include a signal circuit 102 and a determination circuit 104 on a semiconductor chip, and similarly, bump lands 154 </ b> A at one end connected in series by a connection pattern 180. The predetermined inspection signal output from the signal circuit 102 described above is output to 254A, and the inspection signal is input from the bump lands 154B and 254B at the other end via the connection pattern 180.

  Further, the substrate 300 includes an output circuit 106 that outputs the determination result of the determination circuit 104.

  The signal circuit 102 and the determination circuit 104 are controlled by the CPU 50 described above, but can also be controlled by an external jig 113 (see FIG. 2).

  Next, the operation of this embodiment will be described.

  Due to the difference in thermal expansion between the BGA packages 51, 151, and 251 and the printed circuit board 52 after mounting, stress is applied to the soldered portion, for example, soldering defects such as cracks or breakage occur in the solder, and the resistance value rises or breaks. As a result, malfunction occurs. Therefore, it is necessary to detect soldering failure early and to improve the reliability of the product. Therefore, an inspection for early detection of soldering failure will be described.

  First, the inspection of the camera module 12 in the manufacturing process will be described.

  The camera module 12 is attached to a predetermined jig 113 (see FIG. 2). The signal circuit 102 outputs the above-described predetermined inspection signal to the bump land 54A at one end of the BGA package 51 connected in series, and the inspection signal is input to the determination circuit 104 from the bump land 54B at the other end.

  Based on the input inspection signal, the determination circuit 104 determines whether or not there is a crack or the like in the solder joints of the bump lands 54 at the four corners, resulting in poor soldering. Then, the output circuit 106 displays the determination result on the display device 111 (see FIG. 2) of the jig 113. Similarly, the output circuit 106 displays the determination results for the BGA packages 151 and 252 on the display device 111 of the jig 113.

  If any defective solder is found in any of the BGA packages 51, 151, and 251, the soldered portion of the BGA package is repaired and inspected again.

  Note that the inspection signal output from the signal circuit 102 may be any signal such as a DC current, an AC current, a predetermined pulse signal, or the like as long as it can determine whether soldering is good or bad.

  As a determination method of the determination circuit 104, for example, there is a method for determining whether or not an inspection signal is detected, or measuring a resistance value and determining a solder failure when a predetermined resistance value is exceeded. Although depending on the overall configuration of the substrate 300, the resistance value in a state where the circuit is not disconnected is usually around 0.1Ω, and it can be determined that the circuit is disconnected when the resistance value increases by 5 to 10%.

  Next, the inspection after being shipped to the market will be described.

  The camera module 12 is inspected at a predetermined timing (for example, when the power is turned on) as in the above-described manufacturing process. The details will be described below with reference to the flowchart of FIG.

  First, the resistance value is measured in step 502, and it is determined in step 504 whether or not the resistance value is less than a predetermined value. If OK (less than the predetermined value), “OK log” is acquired in 506, and step Proceeding to 610, the log is written in the memory 172. At the same time, the “usage status log” of the usage status of the digital camera 10 is acquired and written in the memory 172.

  In step 508, the normal photographing mode is set. In step 502, the resistance value is measured at a predetermined timing.

  The “usage status log” of the usage status of the digital camera 10 refers to a log of the overall status in which the user has used the digital camera 10 such as the number of power ON / OFF times, the energization time, the number of shutters (shooting).

  Now, in step 504, it is determined that the resistance value is greater than or equal to a predetermined value. If the resistance value is NG (greater than or equal to a predetermined value), the process proceeds to step 510, “NG log” is acquired, . Similarly, the “usage status log” of the usage status of the digital camera 10 is acquired and written in the memory 172.

  In addition, after acquiring “NG log” in step 510, the process proceeds to step 512, and an NG warning display is displayed on the LCD 44 (see FIG. 1). The “NG warning display” displayed on the LCD 44 is preferably a display prompting the user to inspect such as “please send out an inspection because there is a possibility of failure”.

  Note that due to the difference in thermal expansion between the BGA packages 51, 151, and 251 and the printed circuit board 52, stress is usually applied from the soldering of the bump lands 54 at the outermost four corners. Therefore, solder failure first occurs in the bump lands 54 at the four corners of the outermost periphery. However, the bump lands 54 at the four corners are dedicated to monitoring the soldering state. Therefore, even if the soldering of the bump lands 54 at the four corners is defective, the camera function itself is not impaired, and is still usable. However, in the future, it is expected that the soldering of the inner bump land 54 will gradually become stressed and the soldering becomes defective and the function is impaired (fails). Therefore, when a solder failure is detected in the bump lands 54 at the four corners on the outermost periphery, that is, before the function is impaired and the device cannot be used, an “NG warning display” that prompts the user to inspect is displayed. Reliability is improved.

  In addition, the purpose of acquiring the “usage status log” of the usage status of the digital camera 10 and writing it to the memory 172 is that the user requests an inspection by looking at the “NG warning display” or requests a repair due to a failure. This is because the “usage status log”, “OK log”, and “NG log” of the digital camera 10 collected from the market for some reason, such as product life, are read from the memory 172. That is, in order to acquire field data relating to important and valuable soldering reliability corresponding to the use situation, which cannot be obtained by an accelerated test or the like. This field data is valuable data in, for example, manufacturing processes, product improvements, or new product development.

  In addition, since the bump lands 54 of the package substrates 51, 151, 251 for inspecting the soldering state (good or bad) use only the bump lands 54 at the outermost four corners, the package substrates 51, 151, 251 are large. It has not become.

  However, for example, in the method described in Japanese Patent Laid-Open No. 2002-76187, the innermost and outermost electrodes are all connected by the wiring pattern, so that the innermost and outermost electrodes are all soldered. Used to monitor status. That is, one extra electrode is required, and the package substrate becomes large.

  As described above, due to the difference in thermal expansion between the BGA packages 51, 151, 251 and the printed circuit board 52, the stress is usually applied from the soldering of the outermost bump lands 54 (four corner bump lands 54). Take it. Therefore, no problem arises even if the soldering state is monitored using only the bump lands 54 at the four corners of the outermost periphery.

  The present invention is not limited to the above embodiment.

  For example, the determination circuit 104 is included in the package substrates 51, 151, and 251. However, the determination circuit 104 is not limited to this. For example, the printed circuit board 52 (substrate 300) other than the package substrate 51 may be provided at another location. Alternatively, it may be provided on a substrate other than the printed circuit board 52 (substrate 300), for example, the printed wiring board 13 or the printed wiring board 19.

  The output circuit 106 is provided on the printed circuit board 52 (substrate 300), but is not limited to this. It may be provided on a substrate other than the printed circuit board 52 (substrate 300), for example, the printed wiring board 13 or the printed wiring board 19.

  Further, although the present invention has been described with reference to the example applied to the substrate 300 of the camera module 12 of the digital camera 10, it can also be applied to other substrates. Furthermore, the present invention can be applied to all electronic devices other than the digital camera 10.

1 is an external view of a digital camera according to an embodiment of the present invention. It is a schematic block diagram of the control system of the digital camera which concerns on embodiment of this invention. It is a perspective view which shows a camera module. It is a schematic sectional drawing which shows the state before mounting to the printed circuit board of a BGA package. It is a schematic sectional drawing which shows the state after mounting to the printed circuit board of a BGA package. It is a schematic block diagram of the board | substrate mounted to the printed circuit board of a BGA package, and an output circuit. It is a flowchart which monitors the state of soldering. The upper figure is a bottom view and the lower figure is a top view showing the connection pattern. The upper figure which shows the other example of a connection pattern is a bottom view and a lower figure top view.

Explanation of symbols

10 Digital camera (imaging device)
12 Camera module (semiconductor circuit device)
44 LCD (display means)
51 BGA package (package substrate)
52 Printed circuit board 54 Bump land (Electrode of package board)
54A Bump Land (Inspection signal output electrode)
54B Bump Land (Inspection signal input electrode)
57 Semiconductor chip 102 Signal circuit (signal generating means)
104 Judgment circuit (judgment means)
106 Output means (output circuit)
172 memory (storage means)
180 connection pattern

Claims (11)

A semiconductor substrate is mounted on the upper surface, a plurality of electrodes are provided on the lower surface, and the electrode is soldered to a printed circuit board and mounted.
Comprising signal generating means for outputting an inspection signal capable of inspecting the quality of soldering between the electrode and the printed circuit board;
The plurality of electrodes on the outermost periphery are arranged in a substantially rectangular shape,
A package substrate characterized in that at least one of the electrodes located at the four corners of the outermost electrodes arranged in a substantially rectangular shape is an inspection signal output electrode for outputting an inspection signal from the signal generating means. . A package substrate according to claim 1;
A printed circuit board on which the package substrate is mounted by soldering;
The inspection signal is input, and based on the input inspection signal, a determination unit that determines whether soldering between the electrode and the printed circuit board is good,
Output means for outputting a judgment result of the judgment means;
A semiconductor circuit device comprising: Including at least two of the electrodes located at the four corners including the inspection signal output electrode, connected in series in a connection pattern;
3. The semiconductor according to claim 2, wherein at least one of the connected electrodes other than the inspection signal output electrode is an inspection signal input electrode for inputting the inspection signal to the determination means. Circuit device.   4. The semiconductor circuit device according to claim 2, wherein the determination unit is provided on the package substrate.   An imaging apparatus comprising the semiconductor circuit device according to claim 2.   The imaging apparatus according to claim 5, further comprising a display unit that displays a warning based on the determination result output from the output unit.   The imaging apparatus according to claim 5, further comprising a storage unit that stores the determination result output from the output unit.   The imaging device according to claim 7, wherein the storage unit also stores log data of a usage status of the imaging device. A package substrate having a semiconductor chip mounted on the upper surface and a plurality of electrodes on the lower surface;
The printed circuit board on which the electrode of the package substrate is soldered and the package substrate is mounted;
Signal generating means for outputting an inspection signal capable of inspecting the quality of soldering between the electrode and the printed circuit board to any of the electrodes of the package substrate;
The inspection signal is input, and based on the input inspection signal, a determination unit that determines whether soldering between the electrode and the printed circuit board is good,
Output means for outputting a judgment result of the judgment means;
Storage means for storing the determination result output from the output means;
An imaging apparatus comprising:   The image capturing apparatus according to claim 9, wherein the storage unit also stores log data of a usage status of the image capturing apparatus.   The imaging apparatus according to claim 9, further comprising a display unit that displays a warning based on the determination result output from the output unit.

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