High temperature inspection method, inspection system, and electronic apparatus

Abstract

To efficiently conduct high temperature inspection of an electronic apparatus.SOLUTION: In a high temperature inspection method, an electronic apparatus being an inspection object is heated until an internal temperature of the electronic apparatus reaches a temperature that is higher than a prescribed temperature, in a non-energized state, in a high temperature environment. In the high temperature inspection method, operation confirmation of the electronic apparatus is performed when an internal temperature of the heated electronic apparatus is equal to or lower than a first temperature that is lower than a prescribed temperature and equal to or higher than a second temperature that is lower than the first temperature, in an energized state, in a room temperature environment.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a high-temperature inspection method, an inspection system, and an electronic device. [Background technology]

[0002] In the manufacturing process of electronic devices, a burn-in test is performed in which the electronic device is operated at a high temperature (for example, 65° C.) to check for abnormalities. The burn-in test is an example of a high-temperature test.

[0003] There is also known a technique for performing high-temperature inspections using heat generated by electronic devices themselves (see, for example, Patent Document 1). There is also known a technique for stopping the cooling fan of an electronic device when performing high-temperature inspections (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-40093 [Patent Document 2] Japanese Patent Application Publication No. 5-108393 Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional techniques may not be able to efficiently perform high temperature inspections of electronic devices.

[0006] For example, since burn-in testing is performed in a large, constant temperature room, the introduction of testing equipment requires a great deal of expense, and the installation space for the testing equipment is also limited.

[0007] Furthermore, for example, the techniques described in Patent Documents 1 and 2 have the problem that it takes time for the temperature to rise just from the heat generated by the electronic device itself, and in some cases the temperature may not rise to the required level.

[0008] The present invention has been made in view of the above, and has an object to provide an inspection method, an inspection system, and an on-vehicle electronic device that can efficiently perform high-temperature inspection of electronic devices. [Means for solving the problem]

[0009] The inspection method according to the present invention includes heating an electronic device to be inspected in a non-powered state in a high-temperature environment until the internal temperature of the electronic device reaches a temperature higher than a specified temperature. The inspection method then checks the operation of the heated electronic device when the internal temperature of the electronic device is equal to or lower than a first temperature that is lower than the specified temperature and equal to or higher than a second temperature that is lower than the first temperature in a room temperature environment in a powered state. [Effects of the Invention]

[0010] According to the present invention, the electronic device is heated to a temperature higher than the specified temperature for high-temperature testing, and then the operation of the electronic device is checked in an operating state in which heat is generated more than in normal use, thereby making it possible to efficiently perform high-temperature testing of electronic devices. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating a manufacturing flow of an electronic device according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating a hardware configuration of the inspection system according to the embodiment. [Figure 3] FIG. 3 is a diagram showing a hardware configuration of the in-vehicle electronic device according to the embodiment. [Figure 4] FIG. 4 is a diagram illustrating the functional configuration of the controller according to the embodiment. [Figure 5] FIG. 5 is a diagram showing an example of the screen. [Figure 6] FIG. 6 is a diagram showing an example of the screen. [Figure 7] FIG. 7 is a diagram showing an example of the screen. [Figure 8] FIG. 8 is a diagram showing an example of the screen. [Figure 9] FIG. 9 is a flowchart showing a processing procedure of the in-vehicle electronic device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, with reference to the accompanying drawings, embodiments of the high-temperature inspection method, inspection system, and electronic device disclosed in the present application will be described in detail. Note that the present invention is not limited to the embodiments described below. The embodiments are intended to perform high-temperature inspection of electronic devices.

[0013] Here, the electronic device is a device that has a controller and a memory provided in a housing. The controller and the memory may be referred to as a computer.

[0014] For example, the controller may be a central processing unit (CPU), a digital signal processor (DSP), a field programmable gate array (FPGA), a graphics processing unit (GPU), or a system on a chip (SoC).

[0015] 1 is a diagram illustrating the flow of manufacturing an electronic device according to an embodiment, which shows a part of the flow of the manufacturing process of the electronic device.

[0016] As shown in Fig. 1, first, a shipping inspection is performed (step S1). The shipping inspection is an inspection of integrated circuits (ICs) to be installed in electronic devices, and is performed, for example, by the manufacturer that manufactures and ships the ICs. Note that steps S2 and beyond, which will be described later, are performed by the manufacturer that manufactures the electronic devices as finished products (the destination of the ICs).

[0017] Next, a mounting process is performed in which the IC is mounted on a substrate (step S2), followed by an assembly process in which the substrate and other components of the electronic device are assembled (step S3).

[0018] When step S3 is completed, the manufacturing of the hardware of the electronic device is completed. Also, a program for executing the internal machine inspection (step S5) described later is assumed to be stored in advance in a memory provided in the electronic device.

[0019] Next, the electronic device is warmed up without being powered on (step S4). For example, the electronic device is stored in a thermostatic chamber, warmed up in the thermostatic chamber, and then removed from the thermostatic chamber. Also, since the electronic device is powered off in step S4, the controller of the electronic device does not perform any calculations.

[0020] Then, an internal inspection is performed with the electronic device heated to a predetermined temperature (step S5). Here, the predetermined temperature is a temperature that exceeds the lower limit of the internal temperature of the electronic device (hereinafter referred to as the lower limit temperature) set as a requirement for high-temperature inspection.

[0021] As a requirement for the high-temperature inspection, the lower limit temperature is set to 65°C. In other words, the high-temperature inspection must be performed when the internal temperature of the electronic device is 65°C or higher. In this case, the predetermined temperature in step S4 is, for example, 85°C. The predetermined temperature is not limited to 85°C, and may be any temperature that is at least higher than the lower limit temperature and at which the internal temperature of the electronic device is not expected to fall below the lower limit temperature during the internal device inspection.

[0022] During the internal unit inspection, the controller of the electronic device executes the inspection program. During this process, the controller stops the cooling fan installed in the electronic device. This prevents the internal temperature of the electronic device from dropping. The operation of the controller during the internal unit inspection will be described in detail later.

[0023] After the internal device inspection is completed, memory writing is performed (step S6). In memory writing, programs and necessary data to be executed when the electronic device is operated are written to the memory of the electronic device.

[0024] For example, if the electronic device is a car navigation system or a car audio H / U (head unit), the controller of the electronic device controls input and output of data, processes audio signals, and so on.

[0025] Then, a finished product inspection is carried out (step S7). In the finished product inspection, for example, the program written in step S6 is actually executed to confirm that the expected processing results are obtained.

[0026] Each step shown in Fig. 1 may be performed automatically, or some of the steps may be performed manually. For example, steps S4 and S5 may be performed automatically by the inspection system 1 shown in Fig. 2. Fig. 2 is a diagram showing the hardware configuration of the inspection system according to the embodiment.

[0027] 2, the inspection system 1 includes a thermostatic chamber 11, a control device 12, and an in-vehicle electronic device 20. The in-vehicle electronic device 20 is, for example, a head unit.

[0028] The thermostatic chamber 11 includes a heating device 13, a cooling device 14, a temperature sensor 15, and a door 16. The thermostatic chamber 11 also includes a space therein capable of accommodating the in-vehicle electronic device 20. The door 16 is provided as an opening for putting in and taking out the in-vehicle electronic device 20 and can be opened and closed.

[0029] The heating device 13 heats the space inside the thermostatic bath 11. The cooling device 14 cools the space inside the thermostatic bath 11. The temperature sensor 15 measures the temperature inside the thermostatic bath 11.

[0030] Based on the temperature measured by the temperature sensor 15, the control device 12 controls the heating device 13 and the cooling device 14 so that the temperature of the space inside the thermostatic chamber 11 becomes a designated temperature.

[0031] The configuration of the in-vehicle electronic device 20 will be described with reference to Fig. 3. Fig. 3 is a diagram showing the hardware configuration of the in-vehicle electronic device according to the embodiment. As shown in Fig. 3, the in-vehicle electronic device 20 includes a controller 21, an interface 22, a memory 23, a fan 24, a temperature sensor 25, and a display 26.

[0032] The interface 22 inputs and outputs data between the in-vehicle electronic device 20 and other devices. For example, the interface 22 is a port compatible with USB (Universal Serial Bus), Ethernet (registered trademark), or the like.

[0033] The controller 21 reads and executes a program stored in the memory 23. The controller 21 is a CPU, a DSP, an FPGA, a GPU, an SoC, or the like.

[0034] The controller 21 may be a single processor, a multiprocessor configuration, or a multicore configuration having multiple cores in a single chip connected via a single socket.

[0035] The memory 23 is a storage medium such as an eMMC (embedded multi media card), etc. The memory 23 functions as a ROM (read only memory) or a RAM (random access memory).

[0036] The fan 24 is a fan for cooling the in-vehicle electronic device 20. Here, the controller 21, the memory 23, and the temperature sensor 25 are assumed to be housed in a single housing. The fan 24 is an exhaust fan that exhausts air out of the housing, an intake fan that draws air into the housing, or a combination of an exhaust fan and an intake fan. In addition to the fan 24, the in-vehicle electronic device 20 may also have a cooling mechanism such as a heat sink.

[0037] The temperature sensor 25 measures the temperature of the in-vehicle electronic device 20. In particular, the temperature sensor 25 measures the temperature inside the housing of the in-vehicle electronic device 20. The display 26 displays a screen.

[0038] The controller 21 controls each device provided in the in-vehicle electronic device 20. The functional configuration of the controller 21 will be described with reference to Fig. 4. Fig. 4 is a diagram showing the functional configuration of the controller according to the embodiment.

[0039] 4, the controller 21 has a program generation unit 211, a program execution unit 212, a fan control unit 213, and a display control unit 214. The controller 21 performs processing for carrying out the internal machine inspection (step S5) of FIG. 1 using the units shown in FIG. 4.

[0040] The program generation unit 211 generates a test program for carrying out an internal machine inspection. When the controller 21 performs a calculation, a current flows through an electric circuit included in the controller 21, causing the controller 21 to generate heat. The test program causes the controller 21 to execute processes for applying a load in addition to processes necessary for the internal machine inspection.

[0041] The program execution unit 212 executes the test program. Note that the test program is not limited to the one generated by the program generation unit 211, and may be one stored in the memory 23 in advance.

[0042] First, the operator heats the in-vehicle electronic device 20 to be inspected in a high-temperature environment without powering it on until the internal temperature of the in-vehicle electronic device 20 reaches a temperature higher than a specified temperature. After the in-vehicle electronic device 20 is heated in the thermostatic chamber 11 without powering it on (step S4), the process moves to an internal device inspection (step S5), and the program execution unit 212 starts executing the test program. At this time, the controller 21 generates heat as a result of processing to apply a load in accordance with the test program, and a drop in the internal temperature of the in-vehicle electronic device 20 is suppressed.

[0043] The process required for the internal device inspection is for the controller 21 to access each device included in the on-board electronic device 20. If the controller 21 can access each device in a high-temperature state, the internal device inspection is passed. The devices included in the on-board electronic device 20 are an interface 22, a memory 23, a fan 24, a temperature sensor 25, a display 26, etc.

[0044] For example, consider a case where the controller 21 is composed of ten ICs. In this case, one IC of the controller 21 executes a process to access each device included in the in-vehicle electronic device 20. At the same time, the remaining nine ICs execute a process to apply a load. For example, the process to apply a load is a process to continuously access the memory 23.

[0045] At this time, the operator checks the operation of the heated in-vehicle electronic device 20 in a powered state under room temperature conditions when the internal temperature of the in-vehicle electronic device 20 is equal to or lower than a first temperature that is lower than a specified temperature and equal to or higher than a second temperature that is lower than the first temperature. When checking the operation, the operator also causes the controller 21 of the in-vehicle electronic device 20 to simultaneously execute, in addition to the program for checking the operation, another program that imposes a processing load on the controller 21. The other program is a test program. The test program is intended to impose a load on the in-vehicle electronic device 20.

[0046] This allows the on-vehicle electronic device 20 to perform an internal device inspection at a high temperature while preventing a drop in the internal temperature.

[0047] When checking the operation, the operator causes the controller 21 of the on-board electronic device 20 to stop the operation of the cooling fan (fan 24) for dissipating heat inside the on-board electronic device 20 to the outside. The fan control unit 213 controls the operation of the fan 24. The fan control unit 213 stops the fan 24 while the internal equipment inspection is being carried out. This prevents a drop in the internal temperature during the internal equipment inspection. Note that the operation of the cooling fan may be stopped while the controller is executing the other test programs described above. This further prevents a drop in the internal temperature.

[0048] The display control unit 214 displays a screen on the display 26. The display control unit 214 displays information related to the internal machine inspection on the screen.

[0049] After the heating without power supply (step S4) is performed, when power is supplied to the in-vehicle electronic device 20, the display control unit 214 displays a screen as shown in Fig. 5. Fig. 5 is a diagram showing an example of the screen.

[0050] 5, the display control unit 214 causes the display 26 to display an internal machine inspection information display field 261 and a start button 262. The display 26 is a touch panel display. The start button 262 is a virtual button displayed on the display 26.

[0051] The internal machine inspection information display field 261 displays the elapsed time, internal temperature, status, and message. The elapsed time is the time that has elapsed since the test program started. The internal temperature is the temperature that the controller 21 acquired from the temperature sensor 25. The status is the status of the internal machine inspection. The message is text that is displayed as needed.

[0052] In the internal unit inspection, the test program is executed for five minutes. The program execution unit 212 starts executing the test program when the start button 262 is pressed. That is, the start button 262 is a button that causes the in-vehicle electronic device 20 to start the test program in response to an operation.

[0053] 5, the test program has not yet started, the status is "Waiting for test start", and the message "Please press the start button" is displayed. Also, the start button 262 is in a pressable state.

[0054] Here, after the internal temperature rises to 85°C by heating without power supply (step S4), the in-vehicle electronic device 20 is removed from the thermostatic chamber 11 and exposed to room temperature. The room temperature is at most about 30°C, which is lower than the predetermined temperature of 85°C and the lower limit temperature of 65°C. Therefore, the internal temperature continues to drop. Figure 5 shows that the internal temperature has dropped to 75°C.

[0055] As shown in Fig. 6, when the internal temperature is outside the predetermined range, the display control unit 214 displays a warning on the display 26. Fig. 6 is a diagram showing an example of a screen.

[0056] The predetermined range for the internal temperature is set to 65°C to 85°C. FIG. 6 shows that the internal temperature is 55°C. Because the internal temperature is outside the predetermined range, the display control unit 214 sets the status to "Error Occurred" and displays the message "The internal temperature is outside the predetermined range. Please stop the test."

[0057] Furthermore, when the internal temperature is outside the predetermined range, the display control unit 214 changes the display mode of the start button 262 so that it cannot be pressed. In the example of Fig. 6, the display control unit 214 grays out the start button 262.

[0058] 7, while the test program is being executed, the display control unit 214 sets the status to "Test in progress" and displays the message "Test in progress" on the display 26. Fig. 7 is a diagram showing an example of the screen.

[0059] Furthermore, as shown in Fig. 8, when the execution of the test program is completed, the display control unit 214 sets the status to "Test completed" and displays a message saying "Test completed successfully" on the display 26. Fig. 8 is a diagram showing an example of the screen.

[0060] 9 is a flowchart showing the processing procedure of the in-vehicle electronic device according to the embodiment. After being heated to a predetermined temperature in the thermostatic bath 11, the in-vehicle electronic device 20 executes the processing shown in FIG.

[0061] First, the on-vehicle electronic device 20 generates a test program (step S101). The test program is a program that causes the controller 21 to execute processes necessary for inspecting the internal components and processes for applying a load to the controller 21.

[0062] Next, the in-vehicle electronic device 20 stops the fan 24 (step S102). Normally, the in-vehicle electronic device 20 controls the rotation speed of the fan according to the temperature measured by the temperature sensor 25. In contrast, during the internal device inspection, the in-vehicle electronic device 20 prohibits the process of rotating the fan 24. Alternatively, the in-vehicle electronic device 20 may forcefully set the rotation speed of the fan 24 to always be 0.

[0063] The on-board electronic device 20 may stop the fan 24 in response to an operation by the operator, or may automatically stop the fan 24. For example, the operator causes the on-board electronic device 20 to perform the second operation while the cooling fan 24 of the on-board electronic device 20 is stopped. This stops the on-board electronic device 20 from being cooled, and prevents a drop in temperature.

[0064] Next, the on-vehicle electronic device 20 acquires the internal temperature (step S103). The internal temperature may be a sensor value of the temperature sensor 25.

[0065] If the acquired internal temperature is within a predetermined range (step S104, Yes), the in-vehicle electronic device 20 enables the high-temperature inspection mode (step S105). On the other hand, if the acquired internal temperature is not within the predetermined range (step S104, No), the in-vehicle electronic device 20 disables the high-temperature inspection mode (step S109).

[0066] The high temperature inspection mode is a mode provided in the on-board electronic device 20, and is a mode in which an operator can check the operation of the on-board electronic device 20. After enabling the high temperature inspection mode in step S105, the on-board electronic device 20 starts executing a test program (step S106). Furthermore, the on-board electronic device 20 displays the acquired internal temperature on the display 26 (step S107). For example, while executing a program for checking the operation, the controller 21 displays the temperature measured by the temperature sensor 25 on the display 26. Note that when the high temperature inspection mode is disabled, the on-board electronic device 20 may or may not display the internal temperature on the display 26.

[0067] If a high-temperature inspection is performed at a temperature that is not suitable for the inspection, the work will be wasted. By checking the internal temperature before making the inspection possible, the on-board electronic device 20 can reduce wasted work and support the performance of an effective inspection.

[0068] If a predetermined time (e.g., 5 minutes) has elapsed since the start of the test program (step S108, Yes), the in-vehicle electronic device 20 stops the execution of the test program (step S111). On the other hand, if the predetermined time has not elapsed since the start of the test program (step S108, No), the in-vehicle electronic device 20 returns to step S104 and repeats the process.

[0069] After disabling the high-temperature test mode in step S109, the on-board electronic device 20 displays a warning on the screen of the display 26 (step S110) and stops execution of the test program (step S111). As described above, when the high-temperature test mode is disabled, the on-board electronic device 20 disables operation of the start button 262 and causes the display 26 to display a message indicating that the temperature is not within a predetermined range. For example, when the controller 21 is executing a program for checking operation and the temperature measured by the temperature sensor 25 exceeds a first temperature or falls below a second temperature, the controller 21 causes the display 26 to display a message indicating that the operation check will be stopped.

[0070] Up to this point, the explanation has been given assuming that the subject performing the inspection is the operator. The operator can check the operation by visual inspection, etc. For example, the operator checks whether the on-board electronic device 20 is operating normally and whether the on-board electronic device 20 is deformed or damaged.

[0071] On the other hand, the subject that performs the inspection may be an inspection device. For example, the inspection device may perform image recognition processing on an image of the in-vehicle electronic device 20 taken by a camera, and perform operation confirmation similar to visual inspection by an operator. Furthermore, the loading and unloading of the in-vehicle electronic device 20 into the thermostatic chamber 11 may be automated by a robot or the like. This makes it possible to automate the inspection procedure.

[0072] As explained above, the inspection method involves heating the in-vehicle electronic device 20 to be inspected in a non-powered state in a high-temperature environment until the internal temperature of the in-vehicle electronic device 20 reaches a temperature higher than a specified temperature. The inspection method involves checking the operation of the heated in-vehicle electronic device 20 when the internal temperature of the in-vehicle electronic device 20 is equal to or lower than a first temperature lower than the specified temperature and equal to or higher than a second temperature lower than the first temperature in a room temperature environment in a powered state.

[0073] Conventionally, to maintain the internal temperature of electronic devices at a high temperature during high-temperature testing, a thermostatic chamber (temperature-controlled room) large enough for an operator to enter is required. In contrast, in this embodiment, a thermostatic chamber large enough to accommodate the electronic devices is sufficient, reducing the cost, space, and energy required compared to conventional methods. Furthermore, temperature drops due to operations that generate more heat than under normal use conditions are suppressed. As a result, this embodiment enables efficient high-temperature testing of electronic devices.

[0074] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0075] 1. Inspection system 11 Temperature bath 12 Control device 13 Heating device 14 Cooling device 15 Temperature Sensor 16 Doors 20 Automotive electronic equipment 21 Controller 22 Interface 23 Memory 24 Fans 25 Temperature Sensor 26 Display

Claims

1. The electronic device to be inspected is heated in a non-energized state in a high-temperature environment until the internal temperature of the electronic device becomes higher than a specified temperature; The operation of the heated electronic device is checked when the internal temperature of the electronic device is equal to or lower than a first temperature that is lower than the specified temperature and equal to or higher than a second temperature that is lower than the first temperature in a room temperature environment in a powered state. High temperature testing method.

2. When the operation check is performed, the controller of the electronic device is caused to simultaneously execute, in addition to the program for the operation check, another program that imposes a processing load on the controller. The high temperature inspection method of claim 1.

3. When the operation check is performed, the controller of the electronic device is caused to stop operation of a cooling fan for dissipating heat inside the electronic device to the outside.

3. The high-temperature inspection method according to claim 1 or 2.

4. a thermostatic chamber for heating the electronic device to be inspected in a non-energized state in a high-temperature environment until the internal temperature of the electronic device reaches a temperature higher than a specified temperature; and an inspection device that checks the operation of the heated electronic device when the internal temperature of the electronic device is equal to or lower than a first temperature that is lower than the specified temperature and equal to or higher than a second temperature that is lower than the first temperature, in a room temperature environment while the heated electronic device is in a powered state.

5. An electronic device, a temperature sensor for measuring the temperature inside the electronic device; a controller capable of executing a program for checking the operation of the electronic device; Equipped with The controller executes the program for checking the operation when the internal temperature of the electronic device is equal to or lower than a first temperature and equal to or higher than a second temperature that is lower than the first temperature. electronic equipment.

6. The controller simultaneously executes, in addition to the program for checking the operation, another program that imposes a processing load on the controller. The electronic device according to claim 5 .

7. further comprising a cooling fan for dissipating heat inside the electronic device to the outside; The controller stops the operation of the cooling fan when executing the program for checking the operation.

7. The electronic device according to claim 5 or 6.

8. Further comprising a display device, The controller causes the display device to display the temperature measured by the temperature sensor while the program for checking the operation is being executed. The electronic device according to claim 5 .

9. When the temperature measured by the temperature sensor exceeds the first temperature or falls below the second temperature while the program for the operation check is being executed, the controller displays a message on the display device indicating that the operation check is to be stopped.

9. The electronic device according to claim 8.

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