Electronic control device and electronic control method

Abstract

An electronic control device comprises: a first ECU (10) connected to a sensor (30) which can detect a target when a main switch is off, and having a first determination circuit that generates an internal trigger on the basis of the detected value of the sensor (30) and a second determination circuit that is activated by the internal trigger; and a second ECU (20) connected to the first ECU (10) by a communication line. The first determination circuit (11) can operate at low speed when the first ECU (10) is in a sleep state. The second determination circuit (12) is activated by the internal trigger generated in the first determination circuit (11), and operates at a high speed to perform a filtering process. When the first ECU (10) and the second ECU (20) are in the sleep state, the first determination circuit (11) determines whether there is a change in the detected value, and generates an internal trigger when it is determined that there is a change, and after being activated by the internal trigger, the second determination circuit (12) obtains an input value via the filtering process on the detected value of the sensor (30), determines whether there is a change in the input value, and transmits a wake-up signal to the second ECU (20) when it is determined that there is a change.

Description

Technical Field

[0004] , ,

[0001] The present invention relates to an electronic control device and an electronic control method. This application claims priority based on Japanese Patent Application No. 2022-114225 filed on July 15, 2022. For designated countries where incorporation by reference is permitted, the contents described in the above application are incorporated into this application by reference and made part of the description of this application.

Background Art

[0002] Conventionally, in-vehicle electronic systems that suppress power consumption during standby have been known (for example, Patent Document 1). The in-vehicle electronic system described in Patent Document 1 includes a standby ECU that performs standby operation in the IG-OFF state, a plurality of non-standby ECUs that are normally in sleep or off in the IG-OFF state, sensor wires provided between each sensor and the standby ECU for supplying power from the standby ECU to each sensor, and sensor signal lines for taking in signals from each sensor into the standby ECU, and lines G2-G4 provided between each non-standby ECU and the standby ECU for waking up each non-standby ECU. The standby ECU activates the non-standby ECU corresponding to the signal from the sensor via lines G2-G4 in response to the input of the signal from the sensor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the above-mentioned in-vehicle electronic system has a problem in that the standby ECU connected to the sensor needs to remain in a normally running state, resulting in high power consumption by the standby ECU.

[0005] The problem that this invention aims to solve is to provide an electronic control device and an electronic control method that can suppress the power consumption of an ECU connected to a sensor. [Means for solving the problem]

[0006] In this invention, the first ECU and the second ECU are in a sleep state. in The above problem is solved by using an operational first determination circuit to determine whether or not there is a change in the detected value, and when a change is determined to exist, an internal trigger is generated, which activates the second determination circuit, and the second determination circuit then performs filtering on the sensor's detected value to obtain an input value, determines whether or not there is a change in the input value, and if a change is determined to exist, sends a wake-up signal to the second ECU. [Effects of the Invention]

[0007] According to the present invention, the power consumption of the ECU connected to the sensor can be suppressed. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram of an in-vehicle electronic control system according to one embodiment of the present invention. [Figure 2] Figure 2 is a flowchart showing the control processing flow of the first ECU when the first and second ECUs are in a sleep state. [Figure 3] Figure 3 is a flowchart showing the control processing flow of the first ECU when the first and second ECUs are in a normal startup state. [Figure 4] Figure 4 is a block diagram of the first decision circuit. [Modes for carrying out the invention]

[0009] Hereinafter, an embodiment of the electronic control device and electronic control method according to the present invention will be described with reference to the drawings. Figure 1 is a block diagram of an in-vehicle electronic control system according to an embodiment of the present invention. The in-vehicle electronic control system 100 includes a first ECU 10, a second ECU 20, and a sensor 30. The in-vehicle electronic control system 100 is installed in a vehicle and has a communication network for transmitting control signals to in-vehicle equipment such as a battery, motor, and fan, and a control unit for controlling the in-vehicle equipment. Note that the device including at least the first ECU 10 and the second ECU 20 corresponds to the "electronic control device" of the present invention, and the control processing performed in the first ECU 10 corresponds to the "electronic control method" of the present invention.

[0010] The first ECU10 and the second ECU20 are Electronic Control Units (ECCUs) that control in-vehicle equipment and transmit control signals to the in-vehicle equipment. 20 Multiple ECUs, including the above, can send and receive signals from each other. The first ECU 10 and the second ECU 20 each have a memory that stores a program for controlling the in-vehicle equipment, a processor that executes the program stored in the memory, and a communication module that communicates with the in-vehicle equipment and / or other ECUs. The in-vehicle electronic control system also communicates between multiple ECUs and / or between ECUs and other ECUs. device A communication network has been established to enable communication between them, and the ECUs are connected to the nodes of the communication network. The first ECU 10 and the second ECU 20 are in a slave node and master node relationship, and the second ECU 20 is activated by a wake-up signal transmitted from the first ECU 10.

[0011] The in-vehicle electronic control system according to this embodiment is applied to the following system as an example. For example, a sensor 30 connected to the first ECU 10 is a sensor that detects a user approaching the vehicle. The first ECU 10 and the second ECU 20, triggered by the approach of a person, transition from a sleep state to a normal startup state and control the in-vehicle communication device so that it can wirelessly communicate with a key or communication terminal owned by the user. In such a system, when a user approaches, the vehicle's main switch (ignition switch or power switch) is in the off state, and both the first ECU 10 and the second ECU 20 are in a sleep state. Since some circuits of the first ECU 10 are driven at a low speed, the first ECU 10 can determine changes in the input value from the sensor 30 to the input port of the first ECU 10 even in the sleep state. In this state, when the sensor 30 detects the approach of a person, the first ECU 10 activates a high-speed drive circuit included in the first ECU 10 via an internal trigger based on the change in the input value to the input port. Furthermore, the first ECU 10 transmits a wake-up signal to the second ECU 20, causing the second ECU 20 to transition from sleep mode to normal startup mode. Once the second ECU 20 is in normal startup mode, it becomes capable of controlling the in-vehicle communication device. This enables the in-vehicle electronic control system to communicate wirelessly with a user-owned key or communication terminal. The configurations of the in-vehicle electronic control system according to this embodiment will now be described.

[0012] As shown in Figure 1, the first ECU 10 is connected to the sensor 30 and has a first determination circuit 11 that generates an internal trigger based on the value detected by the sensor 30, and a second determination circuit 12 that is activated by the internal trigger. The first ECU 10 is connected to the second ECU 20 by a communication line. The first determination circuit 11 is a circuit that can operate at a low speed when the first ECU 10 is in sleep mode. The first determination circuit 11 does not perform AD conversion that operates with a high-speed clock, nor does it perform filtering processing that performs calculations with a high-speed clock. The first ECU 10 also determines whether or not there is a change in the value detected by the sensor 30, and generates an internal trigger when it determines that there is a change. The value detected by the sensor 30 is input as an analog value to the input port of the first ECU 10. The first ECU 10 acquires the value detected by the sensor 30 at a predetermined period (e.g., 50 msec) in sync with the low-speed clock, and compares the previous value and the current value of the value detected by the sensor 30.

[0013] The sensor 30 detects an analog value, and the first ECU 10 sets a predetermined range including the previous value of the detected value to determine if the detected value has changed, and determines whether the current value of the detected value is within this predetermined range including the previous value. The predetermined range including the previous value indicates the acceptable range of change in the detected value relative to the previous value. For example, if the previous value is 2V, the predetermined range is set to +1V to +3V. For example, the first ECU 10 can set the predetermined range so that the previous value is the midpoint of the predetermined range. If the current value of the detected value is within the predetermined range, the first ECU 10 determines that there has been no change in the detected value. On the other hand, if the current value of the detected value is outside the predetermined range, the first ECU 10 determines that there has been a change in the detected value. If the first ECU 10 determines that there has been a change in the detected value of the sensor 30, it stores the changed detected value in memory as the previous value. Also, if the first ECU 10 determines that there has been a change in the detected value of the sensor 30, it generates an internal trigger. The internal trigger is a command to transition the second determination circuit 12 from sleep state to normal startup state, or in other words, a command to activate some of the circuits within the first ECU 10.

[0014] The second determination circuit 12 is activated by an internal trigger generated by the first determination circuit 11 and operates at high speed to perform filtering. Because the second determination circuit 12 operates at a faster clock speed than the first determination circuit 11, the power consumption of the second determination circuit 12 is higher than that of the first determination circuit 11. When the first ECU 10 is in sleep mode, the second determination circuit 12 is not activated (sleep or hibernation mode), so the power consumption of the first ECU 10 is reduced.

[0015] The second determination circuit 12 acquires the detected value from the sensor 30 at a predetermined period (e.g., 10 msec) in sync with the high-speed clock, and obtains an input value by performing a filtering process on the acquired detected value, and determines whether or not the input value has changed. The filtering process performs an AD conversion on the detected value, and if the continuity of the converted detected value is maintained, the value with continuity is used as the input value. For example, if the same detected value is input three times in a row, the second determination circuit 12 uses the input detected value as the input value. For example, if the AD-converted detected value is 000 or 001, the input value will be "0", and if the detected value is input three times in a row, such as 111, the input value will be "1". In this way, the second determination circuit 12 performs a filtering process to check the continuity of the detected value input in sync with the high-speed clock. Note that the filtering process may include noise reduction, etc.

[0016] The second determination circuit 12 compares the current input value with the previous input value to determine whether or not the input value has changed. If the current input value matches the previous input value, the second determination circuit 12 determines that there has been no change in the input value. If it determines that there has been no change in the input value, the second determination circuit 12 transitions from the normal startup state to the sleep state. The second determination circuit 12 may also output a status signal to the first determination circuit 11 indicating that it has transitioned from the normal startup state to the sleep state.

[0017] When it is determined that there is a change in the input value, the second determination circuit 12 generates a communication event. In the communication event, data is transmitted from the first ECU 10 to the second ECU 20. At this time, if the second ECU 20 is in the sleep state, the second determination circuit 12 transmits a wake-up signal to the second ECU 20. Then, after the second ECU 20 transitions from the sleep state to the normal startup state, the second determination circuit 12 transmits a command for event generation to the second ECU 20. The command for event generation indicates that there has been a change in the input value (corresponding to the detection value of the sensor 30) to the input port of the first ECU 10. Note that when the second ECU 20 is in the normal startup state, the second determination circuit 12 may not transmit a wake-up signal to the second ECU 20. And when the second determination circuit 12 determines that there is a change in the input value, it stores the changed input value in the memory as the previous value.

[0018] When the second ECU 20 receives a wake-up signal from the first ECU 10, it transitions from the sleep state to the normal startup state. Also, the second ECU 20 controls in-vehicle devices according to communication events. The sensor 30 is a sensor that can detect the target regardless of whether the main switch is on or off. The sensor 30 is, for example, a camera, an infrared sensor, a radar, or the like. The detection target of the sensor may be a dynamic object such as a user.

[0019] Next, referring to FIG. 2, the circuit configuration of the first determination circuit 11 will be described. As shown in FIG. 2, the first determination circuit 11 includes a memory 111, an addition circuit 112, a subtraction circuit 113, a selection circuit 114, a switching circuit 115, a D / A converter 116, a comparator 117, and a control determination circuit 118.

[0020] When it is determined that there is a change in the detected value, the memory 111 stores the changed detected value as the previous value. The addition circuit 112 sets the upper limit value of a predetermined range indicating the allowable value by adding a predetermined value to the previous value. The subtraction circuit 113 sets the lower limit value of a predetermined range indicating the allowable value by subtracting a predetermined value from the previous value. The addition circuit 112 and the subtraction circuit 113 are circuits that calculate a predetermined range including the previous value of the detected value, and correspond to the "calculation circuit" of the present invention. The selection circuit 114 selects the calculation value of the addition circuit 112 and the calculation value of the subtraction circuit 113 in accordance with the output of the switching circuit 115, and outputs the selected calculation value to the D / A converter 116.

[0021] The switching circuit 115 switches the selection method of the selection circuit 114 and the determination method of the control determination circuit 118 in accordance with the low-speed clock. For example, the switching circuit 115 outputs a switching signal to the selection circuit 114 so that the selection circuit 114 selects the calculation value of the addition circuit 112 in accordance with the high level of the low clock, and the selection circuit 114 selects the calculation value of the subtraction circuit 113 in accordance with the low level of the low clock.

[0022] The D / A converter 116 converts the output value (digital value) of the selection circuit 114 into an analog value and outputs it to the comparator 117. Note that the D / A converter 116 is a circuit that uniquely determines the output value with respect to the value input from the selection circuit 114 and does not require a clock. The comparator 117 compares the input voltage (analog value) input from the sensor 30 to the input port of the first ECU 10 with the value input from the D / A converter 116, and outputs the comparison result to the control determination circuit 118. Note that an intermittent voltage is supplied to the comparator 117 from the in-vehicle battery, and the intermittent voltage is also supplied to the sensor 30. The control determination circuit 118 determines whether there is a change in the detected value of the sensor 30 from the comparison result between the value input from the D / A converter 116 to the comparator 117 based on the calculation value of the addition circuit 112 and the voltage input from the sensor 30 to the comparator 117, and the comparison result between the value input from the D / A converter 116 to the comparator 117 based on the calculation value of the subtraction circuit 113 and the voltage input from the sensor 30 to the comparator 117, and outputs a signal corresponding to the determination result as a detection signal.

[0023] In this way, the first determination circuit 11 intermittently monitors the input to the input port of the first ECU 10 using a low-speed clock. Intermittent monitoring does not perform calculation processing or filtering processing for AD conversion, thus reducing power consumption. When there is a change in the input to the input port, the second determination circuit 12, which is a slave node in the first ECU 10 and performs calculation processing and filtering processing for AD conversion, is activated. Based on the results of the filtering process, it is determined whether or not there has been a change in the input (analog value) to the input port, and if there is a change, a wake-up signal is sent to the second ECU 20. On the other hand, if there is no change, the first ECU 10 does not send a wake-up signal and the second determination circuit 12 The device is returned to sleep mode, and intermittent monitoring by the first determination circuit 11 continues.

[0024] Next, the control processing flow of the first ECU10 will be explained with reference to Figures 3 and 4. Figure 3 shows the control flow when the first ECU10 and the second ECU20 are in a sleep state, and Figure 4 shows the control flow when the first ECU10 and the second ECU20 are in a normal startup state.

[0025] As shown in Figure 3, in step S1, the first ECU 10 acquires the detected value of the sensor 30 input to the input port. In step S2, the first ECU 10 compares the current value with the previous value of the detected value using the first determination circuit 11 to determine whether or not there has been a change in the detected value. If it is determined that there has been no change in the detected value, the first ECU 10 terminates the control process. The first ECU 10 and the second ECU 20 remain in a sleep state.

[0026] On the other hand, if it is determined that there has been a change in the detected value, in step S3 the first ECU 10 generates an internal trigger to activate the second determination circuit 12. The first ECU 10 also stores the changed detected value in memory as the previous value. In step S4, the second determination circuit 12 is activated (wake-up). In step S5, the first ECU 10 obtains an input value by filtering the detected value of the sensor 30 using the second determination circuit 12. The first ECU 10 compares the current input value with the previous input value using the second determination circuit 12 to determine whether or not there has been a change in the input value. If it is determined that there has been a change in the input value, the first ECU 10 sends a wake-up signal to the second ECU 20 to activate it (step S7). The first ECU 10 also stores the changed input value in memory as the previous value. Then the first ECU 10 terminates its control processing.

[0027] If it is determined that there is no change in the input value, in step S8, the first ECU 10 puts the second determination circuit 12 into sleep mode and terminates the control process.

[0028] When the main switch is ON and the first ECU 10 and second ECU 20 are in a normal startup state, the first ECU 10 executes the control processing flow shown in Figure 4. Since the second determination circuit 12 is in a normal startup state, the filtering process is functioning effectively. In step S11, the first ECU 10 obtains an input value by filtering the detected value of the sensor 30 using the second determination circuit 12.

[0029] In step S12, the first ECU 10 compares the current input value with the previous input value using the second determination circuit 12 to determine whether or not the input value has changed. If it determines that the input value has changed, the first ECU 10 sends an event generation command to the second ECU 20 (step S13). The first ECU 10 also stores the changed input value in memory as the previous value. Then the first ECU 10 terminates the control process. If it determines that there has been no change in the input value, the first ECU 10 terminates the control process.

[0030] As described above, the electronic control device according to this embodiment includes a first ECU 10 connected to a sensor 30 capable of detecting an object when the main switch is off, and a second ECU 20 connected to the first ECU 10 by a communication line. The first ECU 10 includes a first determination circuit 11 that generates an internal trigger based on the detection value of the sensor 30, and a second determination circuit 12 that is activated by the internal trigger. The first determination circuit 11 is a circuit that can operate at a low speed when the first ECU 10 is in sleep mode, and the second determination circuit 12 is a circuit that is activated by the internal trigger generated by the first determination circuit 11 and operates at high speed to perform filtering processing. When the first ECU 10 and the second ECU 20 are in sleep mode, the first determination circuit 11 determines whether there is a change in the detected value. If it determines that there is a change, it generates an internal trigger. The second determination circuit 12, after being activated by the internal trigger, obtains an input value by filtering the detected value of the sensor 30, determines whether there is a change in the input value, and if it determines that there is a change, it sends a wake-up signal to the second ECU. As a result, the first ECU 10 can determine whether there is a change in the detected value with low power consumption, and if there is a change in the detected value, the second ECU 20 can be activated with low power consumption. Consequently, the power consumption of the first ECU 10 connected to the sensor 30 can be suppressed.

[0031] Furthermore, the electronic control method according to this embodiment is the first ECU 10 The processor included in the system executes the following: While the first ECU 10 and second ECU 20 are in sleep mode, the first determination circuit 11 determines whether there is a change in the detected value of the sensor 30. If a change is detected, an internal trigger is generated, which activates the second determination circuit 12. The second determination circuit 12 then performs filtering on the detected value of the sensor 30 to obtain an input value, determines whether there is a change in the input value, and if a change is detected, sends a wake-up signal to the second ECU 20. As a result, the first ECU 10 can determine whether there is a change in the detected value with low power consumption, and if there is a change in the detected value, the second ECU 20 can be activated with low power consumption. Consequently, the power consumption of the first ECU 10 connected to the sensor 30 can be suppressed.

[0032] Furthermore, in the electronic control device according to this embodiment, if the second determination circuit 12 determines that there has been a change in the input value, it stores the changed input value as the previous value, and the input value (Current value) The input value is compared with the previous value to determine whether or not there has been a change. As a result, the second determination circuit 12 can detect changes in the sensor 30's detected value in two stages, and can activate the determination circuit according to the stage. Consequently, the dark current can be reduced in two stages.

[0033] Furthermore, in the electronic control device according to this embodiment, when the first ECU 10 and the second ECU 20 are in a normal operating state, the second determination circuit 12 determines whether or not there has been a change in the input value obtained by filtering the detected value of the sensor 30, and if it determines that there has been a change, it sends an event occurrence command to the second ECU 20. In other words, the first ECU 10 does not need to send an event occurrence command at regular intervals, but only needs to send an event occurrence command when there has been a change in the input value. This makes it possible to suppress the power consumption of the first ECU 10.

[0034] Furthermore, in the electronic control device according to this embodiment, the first determination circuit 11 determines whether or not there is a change in the detected value of the sensor 30 at a predetermined period. As a result, the change in the detected value can be determined at a low clock speed, thus suppressing the power consumption of the first ECU 10.

[0035] Furthermore, in the electronic control device according to this embodiment, if the first determination circuit 11 determines that a change has occurred, it stores the detected value after the change as the previous value, and determines whether or not a change has occurred depending on whether or not the current detected value is within a predetermined range including the previous value. This makes it possible to determine whether or not a change has occurred in the detected value even if the input to the input port is an analog value.

[0036] Furthermore, in the electronic control device according to this embodiment, the second determination circuit 12 enters a sleep state if it determines that there is no change in the input value obtained by filtering the value detected by the sensor 30. This makes it possible to suppress the power consumption of the second ECU 20.

[0037] Furthermore, in the electronic control device according to this embodiment, the first determination circuit 11 includes a memory 111 that stores the detected value after the change as the previous value when it is determined that a change has occurred, an arithmetic circuit that calculates a predetermined range including the previous value, and a comparator 117 that compares the detected value with the calculated value of the arithmetic circuit. This makes it possible to determine whether or not there has been a change in the detected value even if the input to the input port is an analog value.

[0038] The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit it. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention. [Explanation of Symbols]

[0039] 10 1st ECU 11 First judgment circuit 12 Second judgment circuit 20 2nd ECU 30 sensors 100 In-vehicle electronic control systems 111 memory 112 Adding Circuit 113 Subtraction Circuit 114 Selection Circuit 115 Switching Circuit 116 D / A Converters 117 Comparator 118 Control Decision Circuit

Claims

1. A first ECU having a first determination circuit connected to a sensor capable of detecting an object when the main switch is off, which generates an internal trigger based on the detection value of the sensor, and a second determination circuit which is activated by the internal trigger, The system includes a second ECU connected to the first ECU by a communication line, The first determination circuit is a circuit that can operate in the sleep state of the first ECU, The second determination circuit is activated by the internal trigger generated by the first determination circuit and operates at a clock speed faster than the operating clock of the first determination circuit to perform filtering processing. When the first ECU and the second ECU are in a sleep state, The first determination circuit determines whether or not the detected value has changed, and if it determines that there has been a change, it generates the internal trigger, and, The second determination circuit is an electronic control device that, after being activated by the internal trigger, obtains an input value by filtering the detected value, determines whether or not the input value has changed, and if it is determined that there has been a change, transmits a wake-up signal to the second ECU.

2. In the electronic control device according to claim 1, The second determination circuit described above is: If it is determined that the input value has changed, the changed input value is stored as the previous value. An electronic control device that compares the input value with the previous value to determine whether or not the input value has changed.

3. In the electronic control device according to claim 1 or 2, When the first ECU and the second ECU are in a normal startup state, The second determination circuit is an electronic control device that determines whether or not there is a change in the input value obtained by filtering the detected value, and if it determines that there is a change, it transmits an event generation command to the second ECU.

4. In the electronic control device according to claim 1 or 2, The first determination circuit is an electronic control device that determines whether or not the detected value has changed at a predetermined period.

5. In the electronic control device according to claim 1 or 2, If the first determination circuit determines that a change has occurred, it stores the detected value after the change as the previous value. An electronic control device that determines whether or not there has been a change in the detected value, depending on whether the current value of the detected value is within a predetermined range including the previous value.

6. In the electronic control device according to claim 5, The aforementioned previous value is the median value of the predetermined range of the electronic control device.

7. In the electronic control device according to claim 5, The first determination circuit is an electronic control device that determines that there is a change if the current value of the detected value is outside the predetermined range.

8. In the electronic control device according to claim 1 or 2, The second determination circuit is an electronic control device that enters a sleep state if it determines that there is no change in the input value.

9. In the electronic control device according to claim 1 or 2, The first determination circuit is, If a change is detected, a memory is used to store the detected value after the change as the previous value. A calculation circuit that calculates a predetermined range including the previous value, An electronic control device having a comparator that compares the detected value with the calculated value of the calculation circuit.

10. An electronic control method executed by a processor included in the first ECU, The first ECU is, When the main switch is off, it is connected to a sensor capable of detecting the target. It is connected to the second ECU via a communication line. The system includes a first determination circuit that generates an internal trigger based on the sensor's detection value, and a second determination circuit that is activated by the internal trigger. The first determination circuit is a circuit that can operate in the sleep state of the first ECU, The second determination circuit is activated by the internal trigger generated by the first determination circuit and operates at a clock speed faster than the operating clock of the first determination circuit to perform filtering processing. The aforementioned processor, When the first ECU and the second ECU are in sleep mode, the first determination circuit determines whether or not the detected value has changed, and when it determines that there has been a change, it generates the internal trigger. After the second determination circuit is activated by the internal trigger, the second determination circuit performs a filtering process on the detected value to obtain an input value. An electronic control method that determines whether or not the input value has changed, and if it is determined that there has been a change, transmits a wake-up signal to the second ECU.