In-vehicle electronic device, non-volatile memory life prediction method

Abstract

Provided is a vehicle-mounted electronic device including a non-volatile memory and a heat generating component which are mounted on the same board, wherein it is possible to measure the temperature of the non-volatile memory with high accuracy without being affected by the distance from the heat generating component and the usage conditions. This vehicle-mounted electronic component is characterized by comprising: a processing control unit that processes information handled by the electronic component and controls the electronic component; a memory including a plurality of write regions; a temperature sensor; and a remaining warranty period calculation unit that calculates a remaining warranty period of the memory on the basis of the output of the temperature sensor. The vehicle-mounted electronic component is also characterized in that the remaining warranty period calculation unit obtains the remaining warranty period by switching, in accordance with an amount of time from startup of the vehicle-mounted electronic device, between a first determination method for obtaining the remaining warranty period using a first temperature coefficient determined regardless of the distance between the memory and each of a plurality of the temperature sensors, and a second determination method for obtaining the remaining warranty period using a second temperature coefficient determined in accordance with the distance between the memory and each of a plurality of the temperature sensors.

Description

[Technical field]

[0001] The present invention relates to the configuration and control of an electronic device mounted on a vehicle, and in particular to a technique that is effective when applied to predicting the life span of a non-volatile memory mounted in the electronic device. [Background technology]

[0002] With the advancement of autonomous driving (AD) and advanced driver-assistance systems (ADAS), improving the performance and reliability of in-vehicle camera systems has become an important issue.

[0003] In-vehicle cameras used in AD and ADAS include, for example, stereo cameras that simultaneously capture images of an object from different directions using multiple (usually two) cameras, enabling the recording of information about the depth direction as well. The size, position, and speed of multiple three-dimensional objects can be detected by stereoscopic processing of the images captured by the multiple cameras.

[0004] In-vehicle camera systems such as stereo cameras are equipped with non-volatile memory (generally flash memory) for storing captured images, and high performance and reliability of the non-volatile memory are essential to improving the performance and reliability of the in-vehicle camera system.

[0005] Incidentally, non-volatile memories deteriorate due to electrons penetrating the oxide film, which acts as an insulator in accordance with the operating principle, so the number of times data can be rewritten is limited, and the lifespan of the non-volatile memory varies depending on the number of rewrites.

[0006] It is also known that the number of times that non-volatile memories can be rewritten varies depending on the temperature at which they are used. Generally, the number of times that non-volatile memories can be rewritten decreases when they are used at high temperatures.

[0007] Therefore, it is possible to predict the lifespan of a nonvolatile memory based on the number of times the nonvolatile memory is rewritten and the temperature during use.

[0008] In addition, non-volatile memory (flash memory) is broadly divided into NOR type and NAND type. When comparing flash memories of the same capacity, NAND type has poorer data retention characteristics than NOR type, but is relatively low cost. Therefore, if the lifespan of flash memory can be accurately predicted, it may be possible to provide a low-cost in-vehicle camera system that uses NAND type flash memory.

[0009] Background of the present technical field includes, for example, a technology such as Patent Document 1. Patent Document 1 discloses a "memory control device capable of appropriately leveling the degree of wear in a non-volatile memory." [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2014-98978 A Summary of the Invention [Problem to be solved by the invention]

[0011] In an in-vehicle camera system such as that described above, heat-generating components such as a microcontroller equipped with image recognition processing functions are generally mounted on the same board on which the non-volatile memory is mounted, and the temperature to which the non-volatile memory is exposed varies depending on its distance from the heat-generating components on the board.

[0012] In addition, since the way in which heat is generated by heat-generating components varies depending on the conditions under which the vehicle-mounted camera system is used, it is difficult to accurately measure the temperature of the nonvolatile memory, which means that it is difficult to accurately predict the lifespan of the nonvolatile memory.

[0013] In the above-mentioned Patent Document 1, a temperature sensor is provided for each of a plurality of memory cells, a priority is determined for each memory cell according to the measured temperature, and a write process is performed by giving priority to a memory cell with a high priority as the data write destination, thereby making it possible to appropriately level out the degree of wear in a non-volatile memory.

[0014] However, Patent Document 1 does not mention anything about the influence of heat-generating components on the same board as described above, making it difficult to accurately predict the lifespan of a nonvolatile memory.

[0015] Therefore, an object of the present invention is to provide an on-board electronic device having a non-volatile memory and a heat-generating component mounted on the same board, which is capable of measuring the temperature of the non-volatile memory with high accuracy without being affected by the distance from the heat-generating component or the conditions of use, and a method for predicting the life of the non-volatile memory using the same. [Means for solving the problem]

[0016] In order to solve the above problem, the present invention provides an electronic device to be mounted on a vehicle, comprising: a processing control unit that processes information handled by the electronic device or controls the electronic device; a memory having a plurality of write areas; a temperature sensor; and a remaining warranty period calculation unit that calculates a remaining warranty period of the memory based on an output of the temperature sensor, wherein the remaining warranty period calculation unit calculates the remaining warranty period by switching between a first determination method for determining the remaining warranty period using a first temperature coefficient that is determined independently of a distance between the memory and each of the plurality of temperature sensors, and a second determination method for determining the remaining warranty period using a second temperature coefficient that is determined in accordance with a distance between the memory and each of the plurality of temperature sensors, depending on a time from start-up of the on-vehicle electronic device.

[0017] The present invention also provides a method for predicting the life of a non-volatile memory, comprising the steps of: (a) comparing the elapsed time since startup of an in-vehicle electronic device with a predetermined threshold; (b) calculating the remaining warranty period of the memory using a first temperature coefficient determined regardless of the distance between the memory and each of a plurality of temperature sensors; and (c) calculating the remaining warranty period of the memory using a second temperature coefficient determined in accordance with the distance between the memory and each of the plurality of temperature sensors, wherein the remaining warranty period of the memory is calculated by switching between step (b) and step (c) in accordance with the time since startup of the in-vehicle electronic device. Effect of the Invention

[0018] According to the present invention, in an on-board electronic device having a non-volatile memory and a heat-generating component mounted on the same board, it is possible to realize an on-board electronic device capable of measuring the temperature of the non-volatile memory with high accuracy without being affected by the distance from the heat-generating component or the conditions of use, and a method for predicting the life of the non-volatile memory using the same.

[0019] This improves the reliability of the nonvolatile memory and the in-vehicle electronic device using the nonvolatile memory.

[0020] In addition, it will become possible to use NAND flash memory of the same capacity in place of NOR flash memory, which will contribute to reducing the cost of in-vehicle electronic devices.

[0021] Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing a circuit board of an in-vehicle electronic device according to a first embodiment of the present invention; [Diagram 2] 2 is a diagram showing the distance between a temperature sensor and a nonvolatile memory on the board of FIG. 1. [Diagram 3] 4 is a flowchart showing a method for predicting a memory life of an in-vehicle electronic device according to the first embodiment of the present invention. [Figure 4] 10 is a flowchart showing a method for predicting a memory life of an in-vehicle electronic device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same components are designated by the same reference numerals, and detailed description of overlapping parts will be omitted.

[0024] In addition, the following description will be given using an example of a mounting board mounted on an in-vehicle camera system, but the present invention is not limited to this, and can also be applied to in-vehicle electronic devices for other purposes that are equipped with a board on which a non-volatile memory and a heat generating component are mounted on the same board. Therefore, illustration of the configuration as an in-vehicle camera will be omitted. EXAMPLES

[0025] An on-board electronic device according to a first embodiment of the present invention and a method for predicting a lifespan of a nonvolatile memory using the same will be described with reference to Figures 1 to 3. Figure 1 is a diagram showing a board of the on-board electronic device of this embodiment. Figure 2 is a diagram showing the distance between a temperature sensor and a nonvolatile memory on the board of Figure 1. Figure 3 is a flowchart showing a method for predicting a memory lifespan of the on-board electronic device of this embodiment.

[0026] The in-vehicle electronic device of this embodiment includes a main board 100a, and a CMOS board (L) 100b and a CMOS board (R) 100c arranged on the left and right sides of the main board 100a, as shown in Fig. 1. The main board 100a, the CMOS board (L) 100b, and the CMOS board (R) 100c are connected to each other by connection cables 108.

[0027] The main board 100a is equipped with a processing control unit (control microcomputer) 101 that processes information handled by the in-vehicle electronic device or controls the in-vehicle electronic device, memories 102, 103 having multiple write areas, a temperature sensor 104, and a recognition microcomputer 107, which is a heat-generating component.

[0028] The recognition microcomputer 107 has a remaining warranty period calculation unit 107a as part of its functions. The remaining warranty period calculation unit 107a calculates the remaining warranty periods of the memories 102 and 103 based on the output of the temperature sensor 104. The CMOS substrate (L) 100b includes a temperature sensor 105, and the CMOS substrate (R) 100c includes a temperature sensor .

[0029] Here, in the in-vehicle electronic device of this embodiment, the remaining warranty period calculation unit 107a calculates the remaining warranty period by switching between a first determination method for determining the remaining warranty period of the memories 102, 103 using a first temperature coefficient determined regardless of the distance between the memories 102, 103 and each of the multiple temperature sensors 104, 105, and 106, and a second determination method for determining the remaining warranty period of the memories 102, 103 using a second temperature coefficient determined in accordance with the distance between the memories 102, 103 and each of the multiple temperature sensors 104, 105, and 106, depending on the time from the start-up of the in-vehicle electronic device.

[0030] The first and second determination methods will be described in detail below.

[0031] In the first determination method, the following formulas (1) and (2) are used to calculate the remaining warranty period of the memories 102 and 103. The calculation formula of the first determination method is applied in a situation where less than Xmin (for example, less than one minute) has elapsed since the start of the in-vehicle electronic device.

[0032]

number

[0033] Here, W post is the remaining guarantee counter value, W pre is the previous remaining guarantee counter value, W curr is the counter value written this time, and β1 is the temperature coefficient.

[0034]

number

[0035] Here, T1 is, for example, the temperature [K] of the temperature sensor 1 (104).

[0036] In the second determination method, the calculation method is optimized depending on the distance from the recognition microcomputer 107, which is a heat-generating component, to the memories 102 and 103. In the second determination method, the remaining warranty period of the memories 102 and 103 is calculated using the following equations (3), (4), (5), and (6). The calculation equations of the second determination method are applied in a situation where Xmin or more (e.g., one minute or more) has passed since immediately after the start-up of the in-vehicle electronic device.

[0037]

number

[0038] Here, W post_1 is the remaining guaranteed counter value of memory 1 (102), W pre_1 is the previous remaining guarantee counter value of memory 1 (102), W curr_1 is the counter value written this time to memory 1 (102), and β2 is the temperature coefficient of memory 1 (102).

[0039]

number

[0040] Here, T1 is the temperature [K] of the temperature sensor 1 (104), T 123 is the temperature difference [K] between the temperature sensor 1 (104) with the maximum temperature and the temperature sensor 2 (105) with the minimum temperature or the temperature sensor 3 (106), D1 is the distance [m] from the temperature sensor 1 (104) to the memory 1 (102), D 123 is the distance [m] between temperature sensor 1 (104) with the maximum temperature and temperature sensor 2 (105) or temperature sensor 3 (106) with the minimum temperature.

[0041]

number

[0042] Here, W post_2 is the remaining guaranteed counter value of memory 2 (103), W pre_2 is the previous remaining guarantee counter value of memory 2 (103), W curr_2 is the counter value written this time in memory 2 (103), and γ2 is the temperature coefficient of memory 2 (103).

[0043]

number

[0044] Here, D2 is the distance [m] from temperature sensor 1 (104) to memory 2 (103).

[0045] The memory life prediction method for an in-vehicle electronic device according to this embodiment will be described with reference to FIG.

[0046] First, the start-up time is measured by the recognition microcomputer (heat generating component) 107. In step S300, a write event (eg, IGN_ON) occurs in the memories 102 and 103, and in step S301, it is determined whether the time is less than a predetermined threshold value Xmin (eg, less than one minute).

[0047] If it is less than Xmin (No), in step S302, the temperature coefficient of β1 (first temperature coefficient) is used to calculate the remaining guaranteed counter value (first determination method). On the other hand, if it is equal to or greater than Xmin (Yes), in step S303, β2 and γ2 (second temperature coefficients) are used to calculate the remaining guaranteed counter value (second determination method). Then, in step S304, it is determined whether the remaining guarantee counter value is equal to or greater than 0.

[0048] If it is equal to or greater than 0 (Yes), writing to memories 102 and 103 is performed in step S305.

[0049] On the other hand, if it is less than 0 (No), a warning is displayed on the instrument panel in step S306 to notify the driver.

[0050] As described above, the in-vehicle electronic device of this embodiment is an electronic device mounted on a vehicle, and includes a processing control unit (control microcomputer) 101 that processes information handled by the electronic device or controls the electronic device, memories 102, 103 having multiple write areas, temperature sensors 104, 105, 106, and a remaining warranty period calculation unit 107a that calculates the remaining warranty period of the memories 102, 103 based on the outputs of the temperature sensors 104, 105, 106. The remaining warranty period calculation unit 107a calculates the remaining warranty period by switching between a first determination method for determining the remaining warranty period using a first temperature coefficient β1 determined regardless of the distance between the memories 102, 103 and each of the multiple temperature sensors 104, 105, 106 and a second determination method for determining the remaining warranty period using a second temperature coefficient β2 (γ2) determined depending on the distance between the memories 102, 103 and each of the multiple temperature sensors 104, 105, 106 depending on the time from the start-up of the in-vehicle electronic device.

[0051] The timing to switch between the first and second determination methods is determined, for example, by the elapsed time (Xmin or more; for example, 1 minute or more) from the vehicle ignition-on. That is, the remaining warranty period is calculated by the first determination method during the period from the vehicle ignition-on to a predetermined time, and the remaining warranty period is calculated by the second determination method after the predetermined time has elapsed from the vehicle ignition-on.

[0052] In addition, the in-vehicle electronic device of this embodiment is equipped with a heat-generating component (recognition microcomputer) 107 whose temperature rises when the in-vehicle electronic device is started up, and the second temperature coefficient β2 (γ2) is determined according to the distance between the temperature sensor 104, which is located closest to the heat-generating component (recognition microcomputer) 107, and the memories 102 and 103.

[0053] In the method for predicting the lifespan of an in-vehicle electronic device and a non-volatile memory according to this embodiment, the lifespan is predicted taking into consideration the temperature coefficient. In other words, the temperature of the non-volatile memory is estimated using a plurality of temperature sensors 104, 105, and 106, and is used in calculating the lifespan. By dividing the usage conditions (e.g., "immediately after startup" and "after a certain period of time has passed"), the accuracy of estimating the exposure temperature of the non-volatile memory can be improved. Therefore, since the way in which the temperature rises immediately after startup of the in-vehicle electronic device and after a certain period of time differs between summer and winter, predicting the lifespan using the temperature coefficient makes it possible to accurately predict the lifespan of the non-volatile memory.

[0054] In addition, instead of NOR flash memory, which has high data retention characteristics but is relatively expensive, it is possible to effectively utilize NAND flash memory, which is relatively inexpensive but has a short lifespan (low data retention characteristics).

[0055] In addition, by managing the temperature for each memory and each sector and calculating the remaining warranty period, non-volatile memory can be used effectively, and large amounts of data can be handled with the minimum amount of memory required.

[0056] In addition, it can be used in applications where data is frequently rewritten, such as in drive recorders, without worrying about data corruption.

[0057] By employing the in-vehicle electronic device of this embodiment in, for example, an in-vehicle camera system, it is possible to improve the reliability of the in-vehicle camera system and also to employ a NAND type flash memory of the same capacity instead of a NOR type flash memory, thereby contributing to reducing the cost of the in-vehicle camera system.

[0058] In the above, we have described the case where there are two memories, memory 1 (102) and memory 2 (103), but in the case where there are three or more memories, it is possible to calculate the remaining guaranteed counter value in the same way if the distance to each memory is known.

[0059] In addition, the temperature sensor 1 (104) is placed near the recognition microcontroller 107, which is a heat-generating component. However, even if the temperature sensor 1 (104) is not placed nearby, it is possible to predict the life span of each memory by measuring the temperature gradient in the main board 100a in advance and acquiring the measurement data, even if the temperature sensor 1 (104) is not placed in close proximity to the heat-generating component.

[0060] In addition, three temperature sensors (104, 105, 106) are installed, but even if there is only one temperature sensor, it is possible to predict the lifespan by obtaining data on temperature distribution after a certain period of time or according to the surrounding conditions in advance.

[0061] However, since there are many different conditions for data acquisition, such as conditions after the passage of time, ambient conditions, and the amount of information processed within the vehicle-mounted electronic device, it is desirable to install three or more temperature sensors inside the vehicle-mounted electronic device.

[0062] In addition, although this embodiment is described under the assumption that there is one heat-generating component, the present invention can also be applied in cases where there are multiple heat-generating components by understanding the temperature distribution within the main board 100a in advance.

[0063] In this embodiment, the first determination method uses the first temperature coefficient β1 to determine the remaining warranty period, and the second determination method uses the second temperature coefficient β2 (γ2) to determine the remaining warranty period. However, instead of using the temperature coefficients, for example, a conversion table may be created by previously obtaining the relationship between the temperature change over time of the heat-generating component and the number of times the non-volatile memory is rewritten (lifespan) through experiments or simulations, and the method of calculating the remaining warranty period by the remaining warranty period calculation unit 107a may be switched depending on the elapsed time after the start-up of the in-vehicle electronic device. EXAMPLES

[0064] Second embodiment An on-vehicle electronic device and a method for predicting a lifespan of a nonvolatile memory using the same according to a second embodiment of the present invention will be described with reference to Fig. 4. Fig. 4 is a flowchart showing the method for predicting a memory lifespan of the on-vehicle electronic device according to the present embodiment.

[0065] In this embodiment, a method for writing important data to a sector (area) without data corruption by utilizing the remaining guaranteed counter value calculated in the first embodiment will be described. After a write event (eg, IGN_ON) occurs in the memories 102 and 103, first, in step S400, the remaining guaranteed counter value is calculated for each sector using the temperature coefficients β1, β2, and γ2.

[0066] Next, in step S401, it is determined whether the data is of high importance. Examples of "high importance data" here are safety-related information such as "image when pre-crash braking occurs," "other vehicle recognition information when pre-crash braking occurs," and "sign recognition information when pre-crash braking occurs" in the case of an on-board camera, and "distance to an object when pre-crash braking occurs," and "vehicle speed information of the vehicle subject to braking when pre-crash braking occurs" in the case of an on-board radar.

[0067] If the data is of low importance (No), it is confirmed in step S402 whether the guaranteed remaining counter value of the storage sector is 0 or more.

[0068] If it is equal to or greater than 0 (Yes), writing to memories 102 and 103 is performed in step S403.

[0069] On the other hand, if it is less than 0 (No), in step S404 it is confirmed whether the remaining guaranteed counter values ​​of all sectors have been calculated.

[0070] If the remaining guarantee counter values ​​for all sectors have not been calculated (No), the sector is moved in step S405, and the process returns to step S402 to check the remaining guarantee counter value again.

[0071] If the remaining guaranteed counter values ​​for all sectors have been calculated (Yes), a warning is displayed on the instrument panel in step S406 to notify the driver.

[0072] If it is determined in step S401 that the data is of high importance (Yes), then in step S407 it is confirmed whether the guaranteed remaining counter value of the storage sector is equal to or greater than a predetermined threshold value Y.

[0073] If the number is equal to or greater than Y (Yes), writing to memories 102 and 103 is performed in step S408.

[0074] On the other hand, if it is less than Y (No), in step S409 it is confirmed whether the remaining guaranteed counter values ​​of all sectors have been calculated.

[0075] If the remaining guarantee counter values ​​for all sectors have not been calculated (No), the sector is moved in step S410, and the process returns to step S407 to check the remaining guarantee counter value again.

[0076] If the remaining guaranteed counter values ​​of all sectors have been calculated (Yes), a warning is displayed on the instrument panel in step S411 to notify the driver.

[0077] According to this embodiment, writing is performed for each sector (area) of the non-volatile memory taking into consideration the remaining guaranteed counter value and the importance of the data, so that data of high importance can be written to a sector (area) with a high remaining guaranteed counter value (data retention characteristics), thereby improving the reliability of the non-volatile memory and the in-vehicle electronic device using it.

[0078] In the above, the remaining guarantee counter value is calculated after the sector is moved in step S405 or step S410. However, the remaining guarantee counter values ​​of all sectors may be calculated in advance and the information (storage area) may be stored in memories 102 and 103.

[0079] By doing so, when a write event occurs for highly important data, if the sector in which the data is to be stored is less than Y, it can be immediately swapped (exchanged) with a sector that is equal to or greater than Y and has the largest remaining guaranteed counter value.

[0080] As described above, in the in-vehicle electronic device of this embodiment, the remaining warranty period is calculated for each of the multiple write areas of the non-volatile memory, the priority of the information to be written to the non-volatile memory is determined, and information of high importance is written preferentially.

[0081] This allows the prediction of the lifespan of each sector to be calculated, rather than the lifespan of the non-volatile memory alone, making it possible to reliably preserve data of high importance.

[0082] The present invention is not limited to the above-described embodiments, and includes various modified examples. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the configurations described. It is also possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration. [Explanation of symbols]

[0083] 100a...Main board, 100b...CMOS board (L), 100c...CMOS board (R), 101...Processing control unit (control microcomputer), 102...Memory 1, 103...Memory 2, 104...Temperature sensor 1, 105...Temperature sensor 2, 106...Temperature sensor 3, 107...Recognition microcomputer (heat generating component), 107a...Remaining warranty period calculation unit, 108...Connection cable, 200...Distance D1 between temperature sensor 1 and memory 1, 201...Distance D2 between temperature sensor 1 and memory 2

Claims

1. An electronic device mounted on a vehicle, A processing control unit that processes information handled by the electronic device or controls the electronic device; A memory having a plurality of write areas; A temperature sensor; a remaining warranty period calculation unit that calculates a remaining warranty period of the memory based on an output of the temperature sensor, the remaining warranty period calculation unit calculates the remaining warranty period by switching between a first determination method of calculating the remaining warranty period using a first temperature coefficient determined regardless of a distance between the memory and each of the plurality of temperature sensors and a second determination method of calculating the remaining warranty period using a second temperature coefficient determined in accordance with a distance between the memory and each of the plurality of temperature sensors in accordance with a time from a start-up of the in-vehicle electronic device.

2. The in-vehicle electronic device according to claim 1, Calculating the remaining guarantee period for each of the plurality of writing areas; determining a priority of information to be written to the memory; An in-vehicle electronic device that writes information of high importance first.

3. The in-vehicle electronic device according to claim 1, Calculate the remaining warranty period by the first determination method from the time when the vehicle ignition is turned on until a predetermined time is reached, After a predetermined time has elapsed since the vehicle ignition was turned on, the vehicle-mounted electronic device calculates the remaining warranty period using the second determination method.

4. The in-vehicle electronic device according to claim 1, a heat generating component whose temperature increases in response to activation of the vehicle-mounted electronic device; The second temperature coefficient is determined according to a distance between the temperature sensor, which is disposed closest to the heat generating component, and the memory.

5. The in-vehicle electronic device according to claim 1, The memory is a non-volatile memory for storing images captured by an in-vehicle camera.

6. (a) comparing an elapsed time since activation of the vehicle electronic device with a predetermined threshold; (b) calculating a remaining warranty period of the memory using a first temperature coefficient determined regardless of a distance between the memory and each of a plurality of temperature sensors; (c) calculating a remaining warranty period of the memory using a second temperature coefficient determined according to a distance between the memory and each of the plurality of temperature sensors; A method for predicting a life span of a non-volatile memory comprising: A method for predicting a life span of a non-volatile memory, the method comprising: determining a remaining warranty period of the memory by switching between step (b) and step (c) depending on a time from a start-up of the vehicle-mounted electronic device.

7. 7. A method for predicting a life span of a non-volatile memory according to claim 6, comprising: Calculating the remaining guarantee period for each of the plurality of writing areas; determining a priority of information to be written to the memory; A method for predicting the lifespan of a non-volatile memory in which information of high importance is written with priority.

8. 7. A method for predicting a life span of a non-volatile memory according to claim 6, comprising: The remaining warranty period is calculated in step (b) from the time when the vehicle ignition is turned on until a predetermined time is reached, The method for predicting the life span of a non-volatile memory further comprises calculating the remaining warranty period in step (c) after a predetermined time has elapsed since the vehicle ignition was turned on.

9. 7. A method for predicting a life span of a non-volatile memory according to claim 6, comprising: A method for predicting the life of a non-volatile memory, wherein the second temperature coefficient is determined according to the distance between the memory and the temperature sensor, which is located closest to a heat-generating component whose temperature increases upon startup of the vehicle-mounted electronic device.

10. 7. A method for predicting a life span of a non-volatile memory according to claim 6, comprising: The method for predicting a life span of a non-volatile memory, wherein the memory is a non-volatile memory that stores images captured by an in-vehicle camera.

Images