Electronic control unit

Abstract

To provide a technology capable of detecting an opening attack while avoiding countermeasures taken by an opening attacker and enabling internal investigation.SOLUTION: An electronic control apparatus comprises a housing 11, an electronic board 40, a microcomputer 60, a storage medium 70, a capacitance detection circuit 50, an opposing portion 20, a ground 42, and an intermediate portion 30. The capacitance detection circuit includes a wiring pattern 41 disposed on the electronic board. The opposing portion is composed of a conductive material, faces the wiring pattern, and is fixed to the housing or is integrated with the housing. The ground is disposed on the electronic board and is common to the capacitance detection circuit and the opposing portion. The intermediate portion is composed of a non-conductive material, covers the wiring pattern, and is in close contact with the opposing portion. The microcomputer acquires a value corresponding to the capacitance between the wiring pattern and the opposing portion, and if the value corresponding to the detected capacitance falls outside a predetermined range, determines that the housing has been opened and records the determination result in the storage medium.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to electronic control devices. [Background technology]

[0002] The electronic device described in Patent Document 1 includes an opening detection sensor that detects that the housing has been opened, and executes fraud response processing when the opening detection sensor detects that the housing has been opened. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-184535 Summary of the Invention [Problem to be solved by the invention]

[0004] Possible methods for detecting the opening of a housing include detecting the opening of a closed circuit provided in the housing, or detecting the opening of the housing using an optical sensor. However, an attacker who attempts to open the housing may take measures to prevent the opening from being detected by restoring the closed circuit or opening the housing in a dark room.

[0005] In addition, methods for detecting the opening of the housing include firmly fixing or gluing the housing to the internal structure, or placing a corrosive ampoule inside the housing so that the internal structure is physically destroyed when the housing is opened. However, if the internal structure is destroyed when the housing is opened, it becomes difficult for the authorized administrator to open the housing and investigate the inside.

[0006] The present disclosure provides a technology that can detect opening attacks while avoiding countermeasures taken by opening attackers and enabling internal investigation. [Means for solving the problem]

[0007] An electronic control device according to one aspect of the present disclosure includes a housing (11), an electronic board (40), a microcomputer (60), a storage medium (70), a capacitance detection circuit (50), a facing portion (20, 120), a ground (42), and an intermediate portion (30, 130). The electronic board is disposed within the housing. The microcomputer is mounted on the electronic board. The storage medium is mounted on the electronic board. The capacitance detection circuit has a wiring pattern (41, 143, 144) disposed on the electronic board. The facing portion is made of a conductive material, faces the wiring pattern, and is fixed to or integrated with the housing. The ground is disposed on the electronic board and is common to the capacitance detection circuit and the facing portion. The intermediate portion is made of a non-conductive material, covers the wiring pattern, and is in close contact with the facing portion. The microcomputer acquires a value corresponding to the capacitance between the wiring pattern and the facing portion. The microcomputer determines that the enclosure has been opened if the value corresponding to the detected capacitance is outside a preset range, and records the determination result in a storage medium.

[0008] In the electronic control device disclosed herein, when the housing is opened, the capacitance between the wiring pattern and the opposing portion changes, allowing the microcomputer to determine whether the housing has been opened based on the capacitance. Furthermore, the determination result is recorded in a storage medium, allowing an authorized administrator to later recognize that the housing has been opened. Furthermore, changes in capacitance caused by opening the housing are difficult to counter, and opening the housing does not destroy the internal structure. Therefore, the electronic control device can detect opening attacks while avoiding countermeasures taken by opening attackers and enabling internal investigation. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram showing the appearance of an electronic control device according to a first and second embodiment; [Figure 2] 1 is a schematic diagram showing the internal configuration of an electronic control device according to a first embodiment. [Figure 3] 1 is a diagram showing the internal structure of an electronic control device according to a first embodiment. [Figure 4] 1 is a diagram illustrating a capacitance detection circuit according to first and second embodiments. [Figure 5] 4 is a time chart showing the time changes of the output and input of the capacitance detection circuits according to the first and second embodiments. [Figure 6] 4 is a flowchart showing an opening detection process executed by the electronic control device according to the first and second embodiments. [Figure 7] FIG. 6 is a diagram showing the internal structure of an electronic control device according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] (1. First embodiment) <1-1.Configuration> The configuration of an electronic control device 10 according to this embodiment will be described with reference to Figures 1 to 3. The electronic control device 10 has a substantially rectangular parallelepiped shape. The electronic control device 10 is mounted on, for example, a vehicle and controls predetermined functions of the vehicle. The electronic control device 10 includes a housing 11, an electronic board 40, a capacitance detection circuit 50, a microcomputer (hereinafter referred to as MCU) 60, lead terminals 61, a storage medium 70, a power source 80, a facing portion 20, an intermediate portion 30, a wiring pattern 41, and a ground 42.

[0011] The electronic control device 10 also includes a communication unit (not shown) that communicates with the outside of the electronic control device 10. The communication unit may perform wired communication or wireless communication. The outside may be another electronic control device connected to the electronic control device 10 via a communication line, or may be a data center. The communication unit may communicate with the data center via another electronic control device equipped with a wireless communication device. The communication unit may also perform wireless communication with the data center without going through another electronic control device. The data center is a server device connected to a wide area network.

[0012] Housing 11 is made of metal or resin. Housing 11 includes a bottom 17 and a lid 18. Bottom 17 is formed in the shape of a tray with an open top. Lid 18 fits into the opening of bottom 17 to seal bottom 17. Hereinafter, the direction perpendicular to lid 18 will be referred to as the up-down direction.

[0013] The lid 18 includes a first protrusion 12, a second protrusion 13, and a third protrusion 14. The first protrusion 12, the second protrusion 13, and the third protrusion 14 protrude downward from the inner surface of the lid 18. The first protrusion 12 and the second protrusion 13 are disposed at both ends of the lid 18 in the width direction. The third protrusion 14 is disposed approximately in the center of the lid 18 in the width direction. The first protrusion 12 and the second protrusion 13 have the same length in the vertical direction. The lower end of the second protrusion 13 is bent toward the first protrusion 12. The third protrusion 14 is shorter in the vertical direction than the first protrusion 12 and the second protrusion 13.

[0014] The electronic board 40 is a printed wiring board and is built into the housing 11. Specifically, the electronic board 40 is attached so as to contact the lower surfaces of the first protrusion 12 and the second protrusion 13. The wiring pattern 41, the ground 42, the capacitance detection circuit 50, the microcomputer 60, and the lead terminals 61 are mounted on the upper surface of the electronic board 40. The storage medium 70 and the power supply 80 are mounted on the lower surface of the electronic board 40.

[0015] Specifically, the ground 42 and the wiring pattern 41 are disposed between the second protrusion 13 and the third protrusion 14 in the direction along the electronic substrate 40. The ground 42 is disposed in a position in contact with the lower surface of the second protrusion 13. The ground 42 and the wiring pattern 41 are made of metal foil (e.g., copper foil).

[0016] The capacitance detection circuit 50, the microcomputer 60, and the lead terminals 61 are arranged between the third convex portion 14 and the first convex portion 12 in the direction along the electronic substrate 40. The capacitance detection circuit 50 is arranged near the third convex portion 14, and the microcomputer 60 is arranged near the first convex portion 12. The lead terminals 61 extend from the microcomputer 60 along the electronic substrate 40 and are connecting portions that connect the microcomputer 60 to the electronic substrate 40.

[0017] The storage medium 70 and power supply 80 are disposed between the capacitance detection circuit 50 and the microcomputer 60 in the direction along the electronic substrate 40. The storage medium 70 is a semiconductor memory. The power supply 80 supplies power to various circuits on the electronic substrate 40, including the microcomputer 60.

[0018] The facing portion 20 is a plate-like member made of a conductive material. The facing portion 20 is disposed between the second protrusion 13 and the third protrusion 14 so as to contact the inner surface of the lid 18. That is, the facing portion 20 faces the wiring pattern 41. When the housing 11 is made of a conductive material, the facing portion 20 may be integrally formed with the housing 11. For example, the housing 11 and the facing portion 20 may be integrally formed of a metal. Furthermore, when the housing 11 is made of a non-conductive material, the facing portion 20 is fixed to the housing 11. For example, when the housing 11 is made of a resin and the facing portion 20 is made of a metal, the facing portion 20 may be fixed to the lid 18 with an adhesive or the like.

[0019] The facing portion 20 has a protrusion 21 and a contact surface 22. The protrusion 21 protrudes downward from the inner surface of the lid 18. In the up-down direction, the position of the lower surface of the protrusion 21 coincides with the position of the lower surface of the second convex portion 13. The protrusion 21 is in contact with the ground 42. The ground 42 is a common ground for the facing portion 20 and the capacitance detection circuit 50. The contact surface 22 is part or all of the lower surface of the facing portion 20, and has an uneven surface formed thereon.

[0020] The intermediate portion 30 is disposed between the wiring pattern 41 and the facing portion 20. More specifically, the intermediate portion 30 covers the wiring pattern 41 and is in close contact with the contact surface 22. The intermediate portion 30 is made of a non-conductive material, i.e., a dielectric. Therefore, the wiring pattern 41, the facing portion 20, and the intermediate portion 30 constitute a capacitor C1. The wiring pattern 41 and the facing portion 20 form a pair of electrodes of the capacitor C1.

[0021] When the lid 18 is removed from the bottom 17, the middle part 30 splits into a part that is in close contact with the electronic board 40 and a part that is in close contact with the facing part 20. Even if the lid 18 is reattached to the bottom 17, a gap is created in the middle part 30. In other words, once the housing 11 is opened, the capacitance of the capacitor C1 changes. Therefore, the opening of the housing 11 can be detected based on the change in the capacitance of the capacitor C1.

[0022] Therefore, it is desirable that the intermediate portion 30 be flexible so as to enhance the change in capacitance when the housing 11 is opened. Specifically, it is desirable that the intermediate portion 30 be made of a material that causes the amount of change in capacitance relative to a predetermined amount of deformation of the intermediate portion 30 to be greater than a set amount. It is also desirable that the intermediate portion 30 have high thermal conductivity so as to promote heat dissipation from the electronic board 40. The intermediate portion 30 is made of, for example, a non-conductive heat dissipation gel, pillar resin, heat dissipation sheet, paper, ceramic, or the like.

[0023] 4, the capacitance detection circuit 50 includes a resistor 51. The resistor 51 has a first terminal and a second terminal. The first terminal of the resistor 51 is connected to an input / output terminal of the microcomputer 60. The second terminal of the resistor 51 is connected to an analog-to-digital conversion (hereinafter, ADC) terminal of the microcomputer 60. The second terminal of the resistor 51 is also connected to one of a pair of electrodes of the capacitor C1, specifically, to the wiring pattern 41.

[0024] As shown in Figure 5, the output voltage of the microcomputer 60 is input to the capacitance detection circuit 50. The output voltage is a pulse voltage. When the output voltage changes from Lo to Hi, the potential difference ΔVc between the electrodes of the capacitor C1 increases according to the time constant T, and the input value to the ADC terminal of the microcomputer 60 also increases. Furthermore, when the output voltage changes from Hi to Lo, the potential difference ΔVc decreases according to the time constant T, and the input value to the ADC terminal also decreases. The time constant T is determined by the resistance value Ro of the resistor 51 and the capacitance Co of the capacitor C1.

[0025] The period from when the output voltage changes from Hi to Lo to when the ADC input value reaches threshold Vth1 corresponds to time constant T. Threshold Vth1 is a value close to the Lo level, and when the ADC input value falls below threshold Vth1, the potential difference ΔVc can be considered to be Lo. When capacitance Co is within the specified capacitance range, time constant T is T1.

[0026] On the other hand, if the housing 11 is opened and a gap is created in the intermediate portion 30, the capacitance C₇ decreases and falls outside the specified capacitance range. Consequently, the time constant T becomes T2, which is shorter than T1. Furthermore, if an attacker adds a member such as the intermediate portion 30 between the portion of the intermediate portion 30 that is in close contact with the electronic board 40 and the portion that is in close contact with the facing portion 20 after the housing 11 is opened and then closes the lid 18, the capacitance C₇ increases and may fall outside the specified capacitance range. Consequently, the time constant T may become T3, which is longer than T1.

[0027] The microcomputer 60 detects the time constant T and calculates the capacitance C0 from the time constant T and the resistance value R0. The microcomputer 60 then determines whether the casing 11 has been opened based on whether the calculated capacitance C0 is within a specified capacitance range. In another embodiment, the microcomputer 60 may detect the period from when the output voltage changes from L0 to Hi to when the ADC input value reaches the threshold value Vth2 as the time constant T. The threshold value Vth2 is a value close to the Hi level, and when the ADC input value becomes equal to or greater than the threshold value Vth2, the potential difference ΔVc can be considered to be Hi.

[0028] <1-2. Processing> The opening detection process executed by the microcomputer 60 will be described with reference to the flowchart of FIG.

[0029] In S10, the microcomputer 60 determines whether the microcomputer 60 is set to the degenerate mode. The degenerate mode prohibits transition (i.e., access) of applications stored in the microcomputer 60 to areas outside the specific area. In other words, the degenerate mode allows access only to specific areas of the application. On the other hand, the normal mode allows transition to all areas of the application. If the microcomputer 60 determines that the casing 11 has been opened, it sets the microcomputer 60 to the degenerate mode. If the microcomputer 60 determines that the degenerate mode is set, it proceeds to processing of S20, and if it determines that the normal mode is set, it proceeds to processing of S50.

[0030] In S20, the microcomputer 60 determines whether the degraded mode release requirements are met. The release requirements may be, for example, the entry of a password. An authorized administrator can investigate the opened electronic control device 10 by releasing the degraded mode. If the microcomputer 60 determines that the degraded mode release requirements are not met, the process proceeds to S30. If the microcomputer 60 determines that the degraded mode release requirements are met, the process proceeds to S40.

[0031] In S30, the microcomputer 60 continues the degenerate mode and proceeds to the process of S10. In S40, the microcomputer 60 cancels the degenerate mode, sets the microcomputer 60 to the normal mode, and proceeds to the process of S50.

[0032] In S50, the microcomputer 60 obtains the capacitance C0 based on the detected time constant T. Next, in S60, the microcomputer 60 determines whether the capacitance C0 acquired in S50 is within a specified capacitance range. If the microcomputer 60 determines that the capacitance C0 is outside the specified capacitance range, it proceeds to processing in S70. If the microcomputer 60 determines that the capacitance C0 is within the specified capacitance range, it proceeds to processing in S100.

[0033] In S70, the microcomputer 60 increments the counter value N by 1. That is, the microcomputer 60 updates N to N+1. Next, in S80, the microcomputer 60 determines whether the counter value N is less than a specified number of times. If the microcomputer 60 determines that the counter value N is equal to or greater than the specified number of times, it proceeds to processing of S90, and if it determines that the counter value N is less than the specified number of times, it proceeds to processing of S110.

[0034] In S90, the microcomputer 60 changes the mode of the microcomputer 60 to the degenerate mode based on the fact that the capacitance Co has fallen out of the specified capacitance range a specified number of times in succession, and proceeds to the processing of S110. In S100, the microcomputer 60 resets the counter value N to zero.

[0035] Next, in S110, the microcomputer 60 stores the current mode state, the capacitance C0, and the date and time in the storage medium . Next, in S120, the microcomputer 60 transmits a log to the data center via the communication unit. That is, the microcomputer 60 transmits the current mode state, the capacitance C, and the date and time to the data center. After that, the microcomputer 60 returns to the process of S10.

[0036] <1-3.Effects> According to the first embodiment described above in detail, the following effects are achieved. (1) When the housing 11 of the electronic control device 10 is opened, the capacitance C0 between the wiring pattern 41 and the facing portion 20 changes, and the microcomputer 60 can determine whether the housing 11 has been opened based on the capacitance C0. Furthermore, because the determination result is recorded in the storage medium 70, an authorized administrator can later recognize that the housing 11 has been opened. Furthermore, the change in capacitance C0 caused by the opening of the housing 11 is difficult to counter, and the internal structure of the housing 11 is not destroyed even if the housing 11 is opened. Therefore, the electronic control device 10 can detect an opening attack while avoiding countermeasures taken by an opening attacker and enabling internal investigation.

[0037] (2) When the housing 11 is opened, the deformation of the intermediate portion 30 is strengthened by the contact surface 22 having the unevenness, and the change in the capacitance C is strengthened. Therefore, the microcomputer 60 can easily determine that the housing 11 has been opened.

[0038] (3) Because the intermediate portion 30 is flexible, when the housing 11 is opened, the deformation of the intermediate portion 30 is strengthened and the change in the capacitance C is strengthened. Therefore, the microcomputer 60 can easily determine that the housing 11 has been opened.

[0039] (4) The microcomputer 60 can detect the time constant T based on the change in the potential of the wiring pattern 41, and calculate the capacitance C0 from the time constant T and the resistance value R. (5) When it is determined that the casing 11 has been opened, the microcomputer 60 can protect the system and information by prohibiting the application from transitioning outside the specific area.

[0040] (6) By transmitting the log to the data center by the microcomputer 60, a record of the opening of the casing 11 can be left at the data center. This allows a legitimate administrator to investigate the electronic control device 10 later.

[0041] (2. Second Embodiment) <2-1. Differences from the first embodiment> The second embodiment has the same basic configuration as the first embodiment, so differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and reference will be made to the preceding description.

[0042] In the electronic control device 10 according to the first embodiment described above, the intermediate portion 30 covers only the wiring pattern 41. In contrast, the electronic control device 100 according to the second embodiment differs from the first embodiment in that the intermediate portion 130 covers the microcomputer 60, the lead terminals 61, and the lead terminals 71 in addition to the wiring patterns 143, 143.

[0043] 7, differences between the electronic control device 100 and the electronic control device 10 will be described. The electronic control device 100 has wiring patterns 143 and 144 instead of the wiring pattern 41, and has a facing portion 120 and a middle portion 130 instead of the facing portion 20 and the middle portion 30. Furthermore, the electronic control device 100 has lead terminals 71 that connect the storage medium 70 to the electronic board 40.

[0044] The wiring pattern 143 and the wiring pattern 144 form one of a pair of electrodes of the capacitor C1. The facing portion 120 forms the other of the pair of electrodes of the capacitor C1. The wiring pattern 143 is disposed on the upper surface of the electronic substrate 40 and in the vicinity of the third protrusion 14. The wiring pattern 144 is disposed on the upper surface of the electronic substrate 40 and in the vicinity of the ground 42.

[0045] The microcomputer 60 and the storage medium 70 are arranged between the wiring pattern 143 and the wiring pattern 144. More specifically, the microcomputer 60 is arranged on the upper surface of the electronic substrate 40 and in the vicinity of the wiring pattern 143. The storage medium 70 is arranged on the lower surface of the electronic substrate 40 and in the vicinity of the wiring pattern 144. The lead terminals 71 extend upward from the lower surface of the electronic substrate 40 and are connecting portions that connect the storage medium 70 to the electronic substrate 40.

[0046] The facing portion 120 is fixed to the inner surface of the lid 18 or is formed integrally with the lid 18 so as to face the ground 42, the wiring patterns 143 and 144, the microcomputer 60, and the storage medium 70. The lower surface of the facing portion 120 includes a contact surface 122 on which projections and depressions are formed.

[0047] The intermediate portion 130 covers the wiring patterns 143, 144, the microcomputer 60, the lead terminals 61, the storage medium 70, and the lead terminals 71, and is in close contact with the contact surface 122. Like the intermediate portion 30, the intermediate portion 130 is made of a non-conductive material.

[0048] <2-2.Effects> According to the second embodiment described above in detail, in addition to the effects (1) to (6) of the first embodiment described above, the following effect is also achieved.

[0049] (7) Since the intermediate portion 130 covers the lead terminals 61 and 71, the resistance of the microcomputer 60 and the storage medium 70 to side channel attacks can be significantly improved.

[0050] (3. Other Embodiments) Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modified forms.

[0051] (a) In the above embodiment, the microcomputer 60 detects the time constant T and obtains the capacitance C₈ from the time constant T. However, the present disclosure is not limited to this, and the capacitance C₈ may be obtained using other methods. For example, the capacitance detection circuit 50 may be an oscillator circuit or an auto-balancing bridge circuit, and the microcomputer 60 may obtain the capacitance C₈ using a method that uses an oscillator circuit or an auto-balancing bridge method.

[0052] (b) In the above embodiment, the microcomputer 60 calculates the capacitance C0 itself as a value corresponding to the capacitance, and determines whether the housing 11 has been opened based on whether the capacitance C0 is within a specified capacitance range. However, the present disclosure is not limited to this. The microcomputer 60 may also obtain a time constant T as a value corresponding to the capacitance, and determine whether the housing 11 has been opened based on whether the time constant T is within a specified time range.

[0053] (c) When the microcomputer 60 determines that the housing 11 has been opened, the microcomputer 60 is set to the degenerate mode. However, in addition to or instead of setting the microcomputer 60 to the degenerate mode, the security-related data recorded in the storage medium 70 may be deleted. By deleting the security-related data, it is possible to avoid information leakage.

[0054] (d) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0055] (e) In addition to the electronic control device described above, the present disclosure can also be realized in various forms, such as a system that includes the electronic control device as a component, a program for causing a computer to function as the electronic control device, a non-transient physical storage medium such as a semiconductor memory on which this program is recorded, and an opening detection method.

[0056] [Technical idea disclosed in this specification] [Item 1] A housing (11), an electronic board (40) disposed within the housing; a microcomputer (60) mounted on the electronic board; a storage medium (70) mounted on the electronic board; a capacitance detection circuit (50) having wiring patterns (41, 143, 144) arranged on the electronic substrate; a facing portion (20, 120) made of a conductive material, facing the wiring pattern, and fixed to or integrated with the housing; a common ground (42) for the capacitance detection circuit and the opposing portion, which is disposed on the electronic board; an intermediate portion (30, 130) made of a non-conductive material, covering the wiring pattern and in close contact with the opposing portion; The microcomputer acquiring a value corresponding to the capacitance between the wiring pattern and the facing portion; determining that the housing has been opened when a value corresponding to the detected capacitance is outside a preset range; and recording the determination result in the storage medium. Electronic control unit. [Item 2] the facing portion (20, 120) has a contact surface (22, 122) that comes into contact with the intermediate portion (30, 130), The contact surface has irregularities. Item 1. The electronic control device according to item 1. [Item 3] The intermediate portion (30, 130) is flexible, and a change in the capacitance relative to a predetermined deformation amount of the intermediate portion is greater than a set amount. Item 1 or 2. The electronic control device. [Item 4] The capacitance detection circuit (50) has a resistor (51) electrically connected to the wiring patterns (41, 143, 144), The microcomputer (60) detecting a time constant determined by the capacitance and the resistor based on a change in potential of the wiring pattern; and acquiring the capacitance as a value corresponding to the capacitance from the detected time constant and the resistance value of the resistor. 4. The electronic control device according to any one of items 1 to 3. [Item 5] The intermediate portion (30, 130) covers the connection portion (61, 71) between the microcomputer (60) and / or the storage medium (70) and the electronic board (40). 5. The electronic control device according to any one of items 1 to 4. [Item 6] The microcomputer (60) Equipped with applications, When it is determined that the casing (11) has been opened, the transition of the application to a specific area is prohibited. 6. The electronic control device according to any one of items 1 to 5. [Item 7] The microcomputer (60) When it is determined that the housing (11) has been opened, the security-related data recorded in the storage medium (70) is deleted. 7. The electronic control device according to any one of items 1 to 6. [Item 8] The electronic control device further includes a communication unit that communicates with an external device when the microcomputer determines that the housing has been opened. Item 1 or 2. The electronic control device. [Item 9] The communication unit performs wireless communication with a data center. Item 9. The electronic control device according to item 8. [Explanation of symbols]

[0057] 10,100...Electronic control device, 11...Housing, 20,120...Facing portion, 21...Protruding portion, 22,122...Contacting surface, 30,130...Intermediate portion, 40...Electronic board, 41,143,144...Wiring pattern, 42...Ground, 50...Capacitance detection circuit, 51...Resistor, 60...Microcontroller, 61,71...Lead terminal, 70...Storage medium.

Claims

1. A housing (11), an electronic board (40) disposed within the housing; a microcomputer (60) mounted on the electronic board; a storage medium (70) mounted on the electronic board; a capacitance detection circuit (50) having a wiring pattern (41, 143, 144) arranged on the electronic substrate; a facing portion (20, 120) made of a conductive material, facing the wiring pattern, and fixed to or integrated with the housing; a common ground (42) for the capacitance detection circuit and the opposing portion, which is disposed on the electronic board; an intermediate portion (30, 130) made of a non-conductive material, covering the wiring pattern and in close contact with the opposing portion; The microcomputer acquiring a value corresponding to the capacitance between the wiring pattern and the facing portion; determining that the housing has been opened when a value corresponding to the detected capacitance is outside a preset range; and recording the determination result in the storage medium. Electronic control unit.

2. The facing portion (20, 120) has a contact surface (22, 122) that comes into contact with the intermediate portion (30, 130), The contact surface has irregularities. The electronic control device according to claim 1 .

3. The intermediate portion (30, 130) is flexible, and a change in the capacitance relative to a predetermined deformation amount of the intermediate portion is greater than a set amount. The electronic control device according to claim 1 or 2.

4. The capacitance detection circuit (50) has a resistor (51) electrically connected to the wiring patterns (41, 143, 144), The microcomputer (60) detecting a time constant determined by the capacitance and the resistor based on a change in potential of the wiring pattern; and acquiring the capacitance as a value corresponding to the capacitance from the detected time constant and the resistance value of the resistor. The electronic control device according to claim 1 or 2.

5. The intermediate portion (30, 130) covers the connection portion (61, 71) between the microcomputer (60) and / or the storage medium (70) and the electronic board (40). The electronic control device according to claim 1 or 2.

6. The microcomputer (60) Equipped with applications, When it is determined that the casing (11) has been opened, the transition of the application to a specific area is prohibited. The electronic control device according to claim 1 or 2.

7. The microcomputer (60) When it is determined that the housing (11) has been opened, the security-related data recorded in the storage medium (70) is deleted. The electronic control device according to claim 1 or 2.

8. The electronic control device further includes a communication unit that communicates with an external device when the microcomputer determines that the housing has been opened. The electronic control device according to claim 1 or 2.

9. The communication unit performs wireless communication with a data center. The electronic control device according to claim 8.

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