Control device and system

Abstract

To determine a state of an electrostatic sensor with higher accuracy.SOLUTION: A first diagnosis output unit connected to one end of a detection electrode used for detecting electrostatic capacitance, a first diagnosis A / D input unit connected to one end of the detection electrode, a second diagnosis output unit connected to the other end of the detection electrode, and a second diagnosis A / D input unit connected to the other end of the detection electrode, A first circuit resistor disposed between the first diagnosis output unit and the detection electrode and a second circuit resistor disposed between the second diagnosis output unit and the detection electrode have resistance values different from each other, the control unit causes the first diagnosis output unit and the second diagnosis output unit to output voltages different from each other in the diagnosis, and determine a state of the electrostatic sensor based on a voltage input to the first diagnosis A / D input unit and a voltage input to the second diagnosis A / D input unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a control device and a system. [Background technology]

[0002] For example, as disclosed in Patent Document 1, electrostatic sensors that detect the proximity of an object based on a change in electrostatic capacitance are widely used. Also, there is a technology that records in advance the amount of change in electrostatic capacitance when a disconnection occurs in the electrostatic sensor, and detects the disconnection of the electrostatic sensor based on the amount of change. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-015679 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the parasitic capacitance of the electrostatic sensor is small compared to the parasitic capacitance of the entire system, the amount of change when a break occurs in the electrostatic sensor is also small, so it may be difficult to reliably detect the break.

[0005] The present invention has been made in view of the above problems, and an object of the present invention is to determine the state of an electrostatic sensor with higher accuracy. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect of the present invention, there is provided a control device comprising: a control unit that controls diagnosis of an electrostatic sensor; a first diagnostic output unit connected to one end of a detection electrode used to detect electrostatic capacitance; a first diagnostic A / D input unit connected to one end of the detection electrode; a second diagnostic output unit connected to the other end of the detection electrode; and a second diagnostic A / D input unit connected to the other end of the detection electrode, wherein a first circuit resistor arranged between the first diagnostic output unit and the detection electrode and a second circuit resistor arranged between the second diagnostic output unit and the detection electrode have different resistance values, and the control unit, during the diagnosis, causes the first diagnostic output unit and the second diagnostic output unit to output different voltages, and determines the state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit.

[0007] Further, in order to solve the above-mentioned problem, according to another aspect of the present invention, there is provided a system including a control device and a detection electrode used to detect electrostatic capacitance, wherein the control device includes a control unit that controls diagnosis of an electrostatic sensor, a first diagnostic output unit connected to one end of the detection electrode, a first diagnostic A / D input unit connected to one end of the detection electrode, a second diagnostic output unit connected to the other end of the detection electrode, and a second diagnostic A / D input unit connected to the other end of the detection electrode, wherein a first circuit resistor arranged between the first diagnostic output unit and the detection electrode and a second circuit resistor arranged between the second diagnostic output unit and the detection electrode have mutually different resistance values, and the control unit, in the diagnosis, causes the first diagnostic output unit and the second diagnostic output unit to output mutually different voltages, and determines a state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit. [Effects of the Invention]

[0008] As described above, according to the present invention, it is possible to determine the state of the electrostatic sensor with higher accuracy. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing an example of the configuration of a system 1 according to an embodiment of the present invention. [Figure 2] 10A and 10B are diagrams illustrating an example of voltage output according to the embodiment. [Figure 3] 10A and 10B are diagrams illustrating an example of a relationship between a state of the electrostatic sensor and an input voltage in circuit calculation according to the embodiment. [Figure 4] 10 is a diagram showing an example of determination based on a voltage input to a first diagnostic A / D input section 120A and a voltage input to a second diagnostic A / D input section 120B according to the embodiment. FIG. [Figure 5] 10 is a flowchart showing an example of a flow of control by a control unit 100 according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant explanations will be omitted.

[0011] In addition, in this specification and drawings, when multiple identical components are to be described separately, letters or the like may be added to the end of the reference numerals. On the other hand, when it is not necessary to distinguish between multiple identical components, the letters or the like may be omitted and a description common to all of the multiple identical components may be given.

[0012] <1. Embodiment> <<1.1. Configuration Example>> First, a configuration example of a system 1 according to an embodiment of the present invention will be described.

[0013] FIG. 1 is a block diagram showing an example of the configuration of a system 1 according to an embodiment of the present invention.

[0014] As shown in FIG. 1, a system 1 according to this embodiment includes a control board 10 and a detection electrode 20 used to detect capacitance.

[0015] As shown in FIG. 1, the control board 10 also has a microcontroller 15, a circuit resistor R1, a circuit resistor R2, and a connector 17 arranged thereon.

[0016] (Microcontroller 15) The microcontroller 15 of this embodiment includes at least a control unit 100, a first diagnostic output unit 110A, a second diagnostic output unit 110B, a first diagnostic A / D input unit 120A, a second diagnostic A / D input unit 120B, and a capacitance acquisition unit 130.

[0017] (control unit 100) The control unit 100 according to this embodiment controls the diagnosis of the electrostatic sensor.

[0018] Furthermore, one of the features of the control unit 100 according to this embodiment is that, during diagnosis, the control unit 100 causes the first diagnostic output unit 110A and the second diagnostic output unit 110B to output different voltages, and determines the state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit 120A and the voltage input to the second diagnostic A / D input unit 120B.

[0019] The control by the control unit 100 according to this embodiment will be described in detail later.

[0020] (First diagnostic output section 110A, second diagnostic output section 110B) The first diagnostic output section 110A and the second diagnostic output section 110B according to this embodiment output different voltages according to the control of the control section 100 when diagnosing the electrostatic sensor.

[0021] The first diagnostic output section 110A according to this embodiment is connected to one end of the detection electrode 20.

[0022] On the other hand, the second diagnostic output section 110B according to this embodiment is connected to the other end of the detection electrode 20.

[0023] (First diagnostic A / D input unit 120A, second diagnostic A / D input unit 120B) The first diagnostic A / D input section 120A according to this embodiment is connected to one end of the detection electrode 20.

[0024] On the other hand, the second diagnostic A / D input section 120B according to this embodiment is connected to the other end of the detection electrode 20.

[0025] (Capacitance acquisition unit 130) When the electrostatic sensor is not diagnosed, the capacitance acquisition unit 130 according to this embodiment is connected to the detection electrode 20 and a ground electrode (not shown) to acquire (measure) the capacitance.

[0026] (Circuit resistance R1, circuit resistance R2) The circuit resistor R1 according to this embodiment is disposed between the first diagnostic output section 110A and the detection electrode 20. The circuit resistor R1 according to this embodiment is an example of a first circuit resistor.

[0027] On the other hand, the circuit resistor R2 according to this embodiment is disposed between the second diagnostic output section 110B and the detection electrode 20. The circuit resistor R2 according to this embodiment is an example of a second circuit resistor.

[0028] One of the features of the circuit resistors R1 and R2 according to this embodiment is that they have different resistance values.

[0029] (Connector 17) The connector 17 of this embodiment connects the detection electrode 20 to each of the control unit 100, the first diagnostic output unit 110A, the second diagnostic output unit 110B, the first diagnostic A / D input unit 120A, the second diagnostic A / D input unit 120B, and the capacitance acquisition unit 130.

[0030] The connector 17, together with the detection electrode 20, the capacitance acquisition unit 130, and a ground electrode (not shown), constitutes an electrostatic sensor.

[0031] The above describes an example of the configuration of the system 1 according to this embodiment. Note that the configuration described above using Fig. 1 is merely an example, and the configuration of the system 1 according to this embodiment is not limited to this example. The configuration of the system 1 according to this embodiment can be flexibly modified.

[0032] <<1.2. Control Details>> Next, the control of the diagnosis of the electrostatic sensor by the control unit 100 according to this embodiment will be described in detail.

[0033] In the following, an example will be given in which the control unit 100 according to this embodiment controls the first diagnosis and the second diagnosis.

[0034] One of the features of the control unit 100 according to this embodiment is that it causes the first diagnostic output unit 110A and the second diagnostic output unit 110B to output different voltages in each diagnosis.

[0035] FIG. 2 is a diagram showing an example of voltage output according to this embodiment.

[0036] For example, as shown in FIG. 2, in the first diagnosis, the control unit 100 may cause the first diagnostic output unit 110A to output a high voltage and the second diagnostic output unit 110B to output a low voltage.

[0037] In addition, in the second diagnosis, the control unit 100 may cause the first diagnostic output unit 110A to output a low voltage and the second diagnostic output unit 110B to output a high voltage.

[0038] Here, the high voltage is a voltage higher than the low voltage.

[0039] In the following, an example in which the High voltage is 5V and the Low voltage is 0V will be described.

[0040] As described above, one of the features of the circuit resistors R1 and R2 is that they have different resistance values.

[0041] In the following, an example will be described in which the resistance value of the circuit resistor R1 is 3K ohms and the resistance value of the circuit resistor R2 is 2K ohms.

[0042] Next, the relationship between the state of the electrostatic sensor and the input voltage in circuit calculations in this example will be described with reference to FIG.

[0043] First, a case where the electrostatic sensor is in a normal state will be described.

[0044] In this case, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B in the first diagnosis is 2V, which is an intermediate voltage.

[0045] Similarly, in the second diagnosis, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B are the intermediate voltage of 3V.

[0046] From the above, the control unit 100 according to this embodiment may determine that the electrostatic sensor is normal when the voltage input to the first diagnostic A / D input unit 120A and the voltage input to the second diagnostic A / D input unit 120B are approximately the same as the intermediate voltage.

[0047] Next, a case where a short circuit to power occurs in the electrostatic sensor will be described. Here, a short circuit to power means that the electrostatic sensor is short-circuited to the power supply side.

[0048] In this case, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B in the first diagnosis is 5V, which is a high voltage.

[0049] Similarly, in the second diagnosis, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B are 5V, which is a high voltage.

[0050] From the above, the control unit 100 according to this embodiment may determine that a power short has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit 120A and the voltage input to the second diagnostic A / D input unit 120B are approximately the same as the higher voltage (High voltage) between the voltage output by the first diagnostic output unit 110A and the voltage output by the second diagnostic output unit 110B.

[0051] It should be noted that the control unit 100 can determine that a short to power has occurred in the electrostatic sensor based on only one of the first diagnosis and the second diagnosis.

[0052] Next, a case where a ground fault occurs in the electrostatic sensor will be described. Here, a ground fault refers to a short circuit of the electrostatic sensor to the ground potential (GND) side.

[0053] In this case, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B in the first diagnosis is 0V, which is a low voltage.

[0054] Similarly, in the second diagnosis, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B are 0V, which is a low voltage.

[0055] From the above, the control unit 100 according to this embodiment may determine that a ground fault has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit 120A and the voltage input to the second diagnostic A / D input unit 120B are approximately the same as the lower voltage (low voltage) between the voltage output by the first diagnostic output unit 110A and the voltage output by the second diagnostic output unit 110B.

[0056] It should be noted that the control unit 100 can determine that a ground fault has occurred in the electrostatic sensor based on only one of the first diagnosis and the second diagnosis.

[0057] Next, a case where a break occurs in the electrostatic sensor will be described.

[0058] In this case, in the first diagnosis, the voltage input to the first diagnostic A / D input section 120A is a high voltage of 5V, and the voltage input to the second diagnostic A / D input section 120B is a low voltage of 0V.

[0059] On the other hand, in the second diagnosis, the voltage input to the first diagnostic A / D input section 120A is a low voltage of 0V, and the voltage input to the second diagnostic A / D input section 120B is a high voltage of 5V.

[0060] From the above, the control unit 100 according to this embodiment may determine that an open circuit has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit 120A is approximately the same as the voltage output by the first diagnostic output unit 110A, and the voltage input to the second diagnostic A / D input unit 120B is approximately the same as the voltage output by the second diagnostic output unit 110B.

[0061] The control unit 100 can determine that a disconnection has occurred in the electrostatic sensor based on only one of the first diagnosis and the second diagnosis.

[0062] Next, let us consider a case where a rare short occurs, causing the voltage input to the first diagnostic A / D input unit 120A and the second diagnostic A / D input unit 120B to be fixed at a predetermined value. If the predetermined value is approximately the same as the intermediate voltage, it may not be possible to determine the rare short from only one of the first diagnosis or the second diagnosis.

[0063] In this example, it is assumed that the voltage input to the first diagnostic A / D input section 120A and the second diagnostic A / D input section 120B is fixed at 2V due to a layer short.

[0064] In this case, the voltage input to first diagnostic A / D input section 120A and the voltage 2V input to second diagnostic A / D input section 120B in the first diagnosis are equivalent to the intermediate voltage in the first diagnosis.

[0065] For this reason, it is difficult for the control unit 100 to distinguish between normality and a layer short circuit based on the first diagnosis alone.

[0066] On the other hand, in the second diagnosis, the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B are also 2V, but the intermediate voltage in the second diagnosis is 3V.

[0067] Therefore, the control unit 100 can determine that a layer short has occurred in the electrostatic sensor from the results of the first diagnosis and the second diagnosis.

[0068] In view of the above, the control unit 100 according to this embodiment may reverse the voltages output from the first diagnostic output unit 110A and the second diagnostic output unit 110B in the first diagnosis and the second diagnosis, and determine the state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit 120A and the voltage input to the second diagnostic A / D input unit 120B in the first diagnosis, and the voltage input to the first diagnostic A / D input unit 120A and the voltage input to the second diagnostic A / D input unit 120B in the second diagnosis.

[0069] As an example, the control unit 100 according to this embodiment may determine that a layer short has occurred in the electrostatic sensor if the voltage input to the first diagnostic A / D input unit 120A in the first diagnosis and the voltage input to the second diagnostic A / D input unit 120B, and the voltage input to the first diagnostic A / D input unit 120A in the second diagnosis and the voltage input to the second diagnostic A / D input unit 120B are approximately the same.

[0070] Next, with reference to FIG. 4, an example of determination based on the voltage input to first diagnostic A / D input section 120A and the voltage input to second diagnostic A / D input section 120B in this example will be described.

[0071] First, the first diagnosis will be described.

[0072] If the voltage input to the first diagnostic A / D input section 120A is between 1.5V and 2.5V and the voltage input to the second diagnostic A / D input section 120B is between 1.5V and 2.5V, the control section 100 may determine that the electrostatic sensor is normal.

[0073] If the voltage input to the first diagnostic A / D input section 120A is between 4.5V and 5V and the voltage input to the second diagnostic A / D input section 120B is between 4.5V and 5V, the control section 100 may determine that a short to power has occurred in the electrostatic sensor.

[0074] When the voltage input to the first diagnostic A / D input section 120A is between 0V and 0.5V and the voltage input to the second diagnostic A / D input section 120B is between 0V and 0.5V, the control section 100 may determine that a ground fault has occurred in the electrostatic sensor.

[0075] If the voltage input to the first diagnostic A / D input section 120A is between 4.5V and 5V and the voltage input to the second diagnostic A / D input section 120B is between 0V and 0.5V, the control section 100 may determine that a break has occurred in the electrostatic sensor.

[0076] Furthermore, if the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B do not fall into any of the above cases, the control section 100 may determine that some other abnormality has occurred in the electrostatic sensor.

[0077] Next, the second diagnosis will be described.

[0078] If the voltage input to the first diagnostic A / D input section 120A is between 2.5V and 3.5V and the voltage input to the second diagnostic A / D input section 120B is between 2.5V and 3.5V, the control section 100 may determine that the electrostatic sensor is normal.

[0079] If the voltage input to the first diagnostic A / D input section 120A is between 4.5V and 5V and the voltage input to the second diagnostic A / D input section 120B is between 4.5V and 5V, the control section 100 may determine that a short to power has occurred in the electrostatic sensor.

[0080] When the voltage input to the first diagnostic A / D input section 120A is between 0V and 0.5V and the voltage input to the second diagnostic A / D input section 120B is between 0V and 0.5V, the control section 100 may determine that a ground fault has occurred in the electrostatic sensor.

[0081] If the voltage input to the first diagnostic A / D input section 120A is between 0V and 0.5V and the voltage input to the second diagnostic A / D input section 120B is between 4.5V and 5V, the control section 100 may determine that a break has occurred in the electrostatic sensor.

[0082] Furthermore, if the voltage input to the first diagnostic A / D input section 120A and the voltage input to the second diagnostic A / D input section 120B do not fall into any of the above cases, the control section 100 may determine that some other abnormality has occurred in the electrostatic sensor.

[0083] As described above, the control unit 100 can determine whether the abnormality is normal, whether there is a power fault, whether there is a ground fault, whether there is a disconnection, or any other abnormality, based on only one of the first diagnosis or the second diagnosis.

[0084] Furthermore, as described above, the control unit 100 can detect a rare short, etc., in which the voltage input to the first diagnostic A / D input unit 120A and the second diagnostic A / D input unit 120B is fixed at a predetermined value, based on the first diagnosis and the second diagnosis.

[0085] According to the control unit 100 of this embodiment, it is possible to determine the state of the electrostatic sensor with higher accuracy.

[0086] In the above, an example was described in which the high voltage is 5V, the low voltage is 0V, the resistance value of the circuit resistor R1 is 3K ohms, and the resistance value of the circuit resistor R2 is 2K ohms, but the values ​​are not limited to this example.

[0087] The high voltage, low voltage, the resistance value of circuit resistor R1, and the resistance value of circuit resistor R2 may be designed so that there is a sufficient (distinguishable) difference between the intermediate voltage when the electrostatic sensor is normal in the first diagnosis and the intermediate voltage when the electrostatic sensor is normal in the second diagnosis.

[0088] <<1.3. Control Flow>> Next, the flow of control by the control unit 100 according to this embodiment will be described in detail.

[0089] FIG. 5 is a flowchart showing an example of the flow of control by the control unit 100 according to this embodiment.

[0090] In the example shown in FIG. 5, the control unit 100 first controls the capacitance acquisition unit 130 and the diagnostic circuit to switch between open and closed states (S100).

[0091] When diagnosis of the electrostatic sensor is not performed, i.e., when detecting the proximity of an object using the electrostatic sensor, the diagnostic circuits such as the first diagnostic output section 110A, the second diagnostic output section 110B, the first diagnostic A / D input section 120A, and the second diagnostic A / D input section 120B are required to be electrically open (disconnected).

[0092] On the other hand, when diagnosing the electrostatic sensor, the electrostatic capacitance acquisition section 130 is required to be electrically open (disconnected).

[0093] Therefore, when diagnosing the electrostatic sensor, the control unit 100 first controls the capacitance acquisition unit 130 to be open, and controls the diagnostic circuit to be closed.

[0094] Next, the control unit 100 controls the execution of the first diagnosis (S101).

[0095] Next, the control unit 100 controls the execution of the second diagnosis (S102).

[0096] Next, the control unit 100 determines the state of the electrostatic sensor based on the results of the first diagnosis and the second diagnosis (S103).

[0097] Next, the control unit 100 controls the capacitance acquisition unit 130 and the diagnostic circuit to switch between open and closed states (S104), and ends the diagnosis.

[0098] Specifically, the control unit 100 controls the capacitance acquisition unit 130 to be closed, and controls the diagnostic circuit to be open.

[0099] <2. Supplementary Information> Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications and alterations within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

[0100] Furthermore, the series of processes performed by each device described in this specification may be realized by a program stored in a non-transitory computer-readable storage medium. Each program is, for example, loaded into RAM when executed by a computer and executed by a processor such as a CPU. The storage medium may be, for example, a magnetic disk, an optical disk, a magneto-optical disk, or a flash memory. The program may also be distributed, for example, via a network, without using a storage medium. [Explanation of symbols]

[0101] 1: System, 10: Control board, 15: Microcontroller, 17: Connector, 100: Control unit, 110A: First diagnostic output unit, 110B: Second diagnostic output unit, 120A: First diagnostic A / D input unit, 120B: Second diagnostic A / D input unit, 130: Capacitance acquisition unit, 20: Detection electrode, R1, R2: Circuit resistance

Claims

1. a control unit that controls diagnosis of the electrostatic sensor; a first diagnostic output section connected to one end of a detection electrode used to detect capacitance; a first diagnostic A / D input connected to one end of the detection electrode; a second diagnostic output section connected to the other end of the detection electrode; a second diagnostic A / D input connected to the other end of the detection electrode; Equipped with a first circuit resistor disposed between the first diagnostic output section and the detection electrode and a second circuit resistor disposed between the second diagnostic output section and the detection electrode have resistance values ​​different from each other; In the diagnosis, the control unit causes the first diagnostic output unit and the second diagnostic output unit to output different voltages from each other, and determines the state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit. Control device.

2. the control unit determines that the electrostatic sensor is normal when the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit are approximately equal to an intermediate voltage; The control device according to claim 1 .

3. the control unit determines that a short circuit to power has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit are approximately the same as the higher voltage of the voltage output to the first diagnostic output unit and the voltage output to the second diagnostic output unit. The control device according to claim 1 .

4. the control unit determines that a ground fault has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit are approximately the same as the lower of the voltages output by the first diagnostic output unit and the second diagnostic output unit. The control device according to claim 1 .

5. the control unit determines that a disconnection has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit is approximately the same as the voltage output by the first diagnostic output unit and the voltage input to the second diagnostic A / D input unit is approximately the same as the voltage output by the second diagnostic output unit. The control device according to claim 1 .

6. the control unit reverses the voltages output from the first diagnostic output unit and the second diagnostic output unit in the first diagnosis and the second diagnosis, and determines the state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit in the first diagnosis, and the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit in the second diagnosis. The control device according to claim 1 .

7. the control unit determines that a layer short has occurred in the electrostatic sensor when the voltage input to the first diagnostic A / D input unit in the first diagnosis and the voltage input to the second diagnostic A / D input unit in the second diagnosis are approximately the same, and the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit in the second diagnosis are approximately the same. The control device according to claim 6.

8. Further, a capacitance acquisition unit connected to the detection electrode is provided, When the diagnosis is performed, the control unit controls the capacitance acquisition unit to be open. The control device according to any one of claims 1 to 7.

9. When the diagnosis is not performed, the control unit controls the first diagnostic output unit, the first diagnostic A / D input unit, the second diagnostic output unit, and the second diagnostic A / D input unit to be open. The control device according to claim 1 .

10. a control device and a detection electrode used to detect capacitance; The control device a control unit that controls diagnosis of the electrostatic sensor; a first diagnostic output section connected to one end of the detection electrode; a first diagnostic A / D input connected to one end of the detection electrode; a second diagnostic output section connected to the other end of the detection electrode; a second diagnostic A / D input connected to the other end of the detection electrode; Equipped with a first circuit resistor disposed between the first diagnostic output section and the detection electrode and a second circuit resistor disposed between the second diagnostic output section and the detection electrode have resistance values ​​different from each other; In the diagnosis, the control unit causes the first diagnostic output unit and the second diagnostic output unit to output different voltages from each other, and determines the state of the electrostatic sensor based on the voltage input to the first diagnostic A / D input unit and the voltage input to the second diagnostic A / D input unit. system.

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