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]

[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, and for designated states where incorporation by reference of literature is permitted, the contents of the above application are incorporated by reference into this application and made part of the description of this application. [Background technology]

[0002] Conventionally, an in-vehicle electronic system that suppresses power consumption during standby has 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 an IG off state, a plurality of non-standby ECUs that are normally in sleep or off in an IG off state, sensor wires provided between each of the sensors and the standby ECU for supplying power from the standby ECU to each of the sensors, a sensor signal wire that takes in signals from each of the sensors to the standby ECU, and lines G2-G4 provided between each of the non-standby ECUs and the standby ECU for waking up each of the non-standby ECUs, and the standby ECU starts up the non-standby ECU according to the signal from the sensor via the lines G2-G4 in response to the input of a signal from the sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-280314 A Summary of the Invention [Problem 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 maintain a normal operating state, resulting in high power consumption by the standby ECU.

[0005] An object of the present invention is to provide an electronic control device and an electronic control method that can reduce the power consumption of an ECU connected to a sensor. [Means for solving the problem]

[0006] The present invention solves the above problem by having a first judgment circuit capable of operating at a low speed while the first ECU and second ECU are in a sleep state determine whether or not there has been a change in the detection value, generate an internal trigger when it is determined that there has been a change, and activate a second judgment circuit using the internal trigger, after which the second judgment circuit obtains an input value by performing a filtering process on the detection value of the sensor, determines whether or not there has been a change in the input value, and if it is determined that there has been a change, sends a wake-up signal to the second ECU. Effect of the Invention

[0007] According to the present invention, it is possible to reduce the power consumption of an ECU connected to a sensor. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram of an in-vehicle electronic control system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a flowchart showing a control process flow of the first ECU when the first and second ECUs are in a sleep state. [Diagram 3] FIG. 3 is a flowchart showing a control process flow of the first ECU when the first and second ECUs are in a normal startup state. [Figure 4] FIG. 4 is a block diagram of the first determination circuit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of an electronic control device and an electronic control method according to the present invention will be described below with reference to the drawings. FIG. 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 provided in a vehicle, and includes a communication network for transmitting control signals to in-vehicle devices such as a battery, a motor, and a fan, and a control unit for controlling the in-vehicle devices. Note that an apparatus 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 process executed by the first ECU 10 corresponds to the "electronic control method" of the present invention.

[0010] The first ECU 10 and the second ECU 20 are controllers (Electronic Control Units) that control in-vehicle devices and transmit control signals to the in-vehicle devices. 20 The first ECU 10 and the second ECU 20 each have a memory that stores a program for controlling the in-vehicle devices, a processor that executes the program stored in the memory, and a communication module that communicates with the in-vehicle devices and / or other ECUs. The in-vehicle electronic control system also has communication between the multiple ECUs and / or between the ECU and the in-vehicle devices. device A communication network that enables communication between the ECUs is constructed, 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 started up by a wake-up signal transmitted from the first ECU 10.

[0011] The in-vehicle electronic control system according to the present embodiment is applied to the following system, for example. For example, the sensor 30 connected to the first ECU 10 is a sensor that detects the approach of a user to the vehicle. The first ECU 10 and the second ECU 20 control the in-vehicle communication device to transition from a sleep state to a normal activation state using the approach of a person as a trigger, and to wirelessly communicate with a key or a communication terminal owned by the user. In such a system, when the user approaches, the main switch (ignition switch or power switch) of the vehicle is in an 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 determines a change 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 driving circuit included in the first ECU 10 with 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 to transition the second ECU 20 from a sleep state to a normal startup state. When the second ECU 20 enters the normal startup state, the second ECU 20 is in a state in which it can control the in-vehicle communication device. This allows the in-vehicle electronic control system to wirelessly communicate with a user's key or a communication terminal. Each component of the in-vehicle electronic control system according to this embodiment will be described below.

[0012] As shown in FIG. 1, the first ECU 10 has a first judgment circuit 11 connected to the sensor 30 and generating an internal trigger based on the detection value of the sensor 30, and a second judgment circuit 12 activated by the internal trigger. The first ECU 10 is connected to the second ECU 20 by a communication line. The first judgment circuit 11 is a circuit that can operate at a low speed in the sleep state of the first ECU 10. The first judgment circuit 11 does not perform AD conversion that operates with a high-speed clock and filtering processing that performs arithmetic processing with a high-speed clock. The first ECU 10 also judges whether or not there is a change in the detection value of the sensor 30, and generates an internal trigger when it judges that there is a change. The detection value of the sensor 30 is input to an input port of the first ECU 10 as an analog value. The first ECU 10 acquires the detection value of the sensor 30 at a predetermined period (e.g., 50 msec) in accordance with the low-speed clock, and compares the previous value and the current value of the detection value of the sensor 30.

[0013] The detection value of the sensor 30 is an analog value, and the first ECU 10 sets a predetermined range including the previous value of the detection value in order to determine a change in the detection value, and determines whether the current detection value is within the predetermined range including the previous value. The predetermined range including the previous value indicates the allowable range of the change in the detection value from 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 may set the predetermined range so that the previous value is the median value of the predetermined range. Then, if the current detection value is within the predetermined range, the first ECU 10 determines that the detection value has not changed. On the other hand, if the current detection value is outside the predetermined range, the first ECU 10 determines that the detection value has changed. If it is determined that the detection value of the sensor 30 has changed, the first ECU 10 stores the detection value after the change in memory as the previous value. Also, if it is determined that the detection value of the sensor 30 has changed, the first ECU 10 generates an internal trigger. The internal trigger is a command for causing the second determination circuit 12 to transition from a sleep state to a normal activation state, in other words, a command for activating some of the circuits in the first ECU .

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

[0015] The second judgment circuit 12 acquires the detection value of the sensor 30 at a predetermined period (for example, 10 msec) in accordance with the high-speed clock, obtains an input value by performing a filtering process on the acquired detection value, and judges whether the input value has changed. The filtering process converts the detection value into an AD conversion value, and if the continuity of the converted detection value is maintained, the value having the continuity is set as the input value. For example, if the same detection value is input three times in succession, the second judgment circuit 12 sets the input detection value as the input value. For example, if the AD converted detection value is 000 or 001, the input value becomes "0", and if the detection value is input three times in succession, such as 111, the input value becomes "1". In this way, the second judgment circuit 12 executes a filtering process to check the continuity of the detection value input in accordance with the high-speed clock. The filtering process may include noise removal, etc.

[0016] The second judgment circuit 12 compares the current value and the previous value of the input value to judge whether the input value has changed. If the current value of the input value matches the previous value, the second judgment circuit 12 judges that the input value has not changed. If it is determined that the input value has not changed, the second judgment circuit 12 transitions from the normal startup state to the sleep state. The second judgment circuit 12 may also output a state signal indicating the transition from the normal startup state to the sleep state to the first judgment circuit 11.

[0017] When it is determined that the input value has changed, 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, when the second ECU 20 is in a 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 a normal startup state, the second determination circuit 12 transmits a command for event occurrence to the second ECU 20. The command for event occurrence 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 a normal startup state, the second determination circuit 12 does not need to transmit a wake-up signal to the second ECU 20. Then, when it is determined that the input value has changed, the second determination circuit 12 stores the changed input value in a memory as a previous value.

[0018] When the second ECU 20 receives a wake-up signal from the first ECU 10, the second ECU 20 transitions from the sleep state to a normal startup state. The second ECU 20 also controls in-vehicle devices in response to a communication event. The sensor 30 is a sensor that can detect an object not only when the main switch is on but also when it is off. The sensor 30 is, for example, a camera, an infrared sensor, a radar, or the like. The object to be detected by the sensor may be a dynamic object such as a user.

[0019] Next, the circuit configuration of the first judgment circuit 11 will be described with reference to Fig. 2. As shown in Fig. 2, the first judgment circuit 11 has a memory 111, an adder circuit 112, a subtracter circuit 113, a selector circuit 114, a switching circuit 115, a D / A converter 116, a comparator 117, and a control decision circuit 118.

[0020] When it is determined that the detection value has changed, the memory 111 stores the detected value after the change as the previous value. The adder circuit 112 adds a predetermined value to the previous value to set the upper limit of a predetermined range indicating the allowable value. The subtracter circuit 113 subtracts a predetermined value from the previous value to set the lower limit of the predetermined range indicating the allowable value. The adder circuit 112 and the subtracter circuit 113 are circuits that calculate a predetermined range including the previous value of the detection value, and correspond to the "arithmetic circuit" of the present invention. The selector circuit 114 selects the calculated value of the adder circuit 112 or the calculated value of the subtracter circuit 113 according to the output of the switch circuit 115, and outputs the selected calculated 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 decision 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 adder circuit 112 in accordance with the high level of the low-speed clock and selects the calculation value of the subtractor circuit 113 in accordance with the low level of the low-speed 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. The D / A converter 116 is a circuit that uniquely determines an output value for the value input from the selection circuit 114, and does not require a clock. The comparator 117 compares an input voltage (analog value) input from the sensor 30 to an input port of the first ECU 10 with a value input from the D / A converter 116, and outputs the comparison result to the control decision circuit 118. An intermittent voltage is supplied to the comparator 117 from the vehicle battery, and the intermittent voltage is also supplied to the sensor 30. The control decision circuit 118 determines whether or not there has been a change in the detection value of the sensor 30 based on 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 based on 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 according to the determination result as a detection signal.

[0023] In this way, the first judgment circuit 11 uses a low-speed clock to intermittently monitor the input to the input port of the first ECU 10. Intermittent monitoring does not perform arithmetic processing or filtering processing for AD conversion, thereby reducing power consumption. If there is a change in the input to the input port, the first judgment circuit 11 activates the second judgment circuit 12, which is a circuit in the first ECU 10 that is a slave node and performs arithmetic processing and filtering processing for AD conversion. Then, based on the results of the filtering processing, it determines whether or not there is a change in the input to the input port (analog value), and if there is a change, it transmits a wake-up signal to the second ECU 20. On the other hand, if there is no change, the first ECU 10 does not transmit a wake-up signal and activates the second judgment circuit 12 The first determination circuit 11 then returns to the sleep state, and the first determination circuit 11 continues intermittent monitoring.

[0024] Next, a control process flow of the first ECU 10 will be described with reference to Fig. 3 and Fig. 4. Fig. 3 shows a control flow when the first ECU 10 and the second ECU 20 are in a sleep state, and Fig. 4 shows a control flow when the first ECU 10 and the second ECU 20 are in a normal startup state.

[0025] As shown in Fig. 3, in step S1, the first ECU 10 acquires the detection value of the sensor 30 input to the input port. In step S2, the first ECU 10 uses the first determination circuit 11 to compare the current detection value with the previous detection value and determines whether or not the detection value has changed. If it is determined that the detection value has not changed, the first ECU 10 ends the control process. Note that the first ECU 10 and the second ECU 20 remain in the sleep state.

[0026] On the other hand, if it is determined that the detected value has changed, the first ECU 10 generates an internal trigger to start the second determination circuit 12 in step S3. The first ECU 10 also stores the changed detected value in memory as a previous value. The second determination circuit 12 is started (wake-up) in step S4. In step S5, the first ECU 10 obtains an input value by performing a filtering process on the detected value of the sensor 30 using the second determination circuit 12. The first ECU 10 compares the current value and the previous value of the input value using the second determination circuit 12 to determine whether the input value has changed. If it is determined that the input value has changed, the first ECU 10 transmits a wake-up signal to the second ECU 20 to start the second ECU 20 (step S7). The first ECU 10 also stores the changed input value in memory as a previous value. The first ECU 10 then ends the control process.

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

[0028] When the main switch is in an ON state and the first ECU 10 and the second ECU 20 are in a normal startup state, the first ECU 10 executes the control process flow shown in Fig. 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 performing a filtering process on the detection value of the sensor 30 using the second determination circuit 12.

[0029] In step S12, the first ECU 10 uses the second judgment circuit 12 to compare the current value and the previous value of the input value and judges whether the input value has changed. If it is judged that the input value has changed, the first ECU 10 transmits a command for event occurrence 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 ends the control process. If it is judged that the input value has not changed, the first ECU 10 ends the control process.

[0030] As described above, the electronic control device according to this embodiment has a first ECU 10 connected to a sensor 30 capable of detecting an object when a main switch is in an off state, and a second ECU 20 connected to the first ECU 10 by a communication line. The first ECU 10 has a first determination circuit 11 that generates an internal trigger based on a 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 a sleep state, and the second determination circuit 12 is a circuit that is activated by an internal trigger generated by the first determination circuit 11 and operates at a high speed to perform filtering processing. When the first ECU 10 and the second ECU 20 are in a sleep state, the first judgment circuit 11 judges whether or not there is a change in the detection value, and generates an internal trigger when it judges that there is a change, and the second judgment circuit 12, after being started by the internal trigger, obtains an input value by filtering the detection value of the sensor 30, judges whether or not there is a change in the input value, and transmits a wake-up signal to the second ECU when it judges that there is a change. This allows the first ECU 10 to judge whether or not there is a change in the detection value with low power consumption, and to start up the second ECU 20 with low power consumption when there is a change in the detection value. As a result, the power consumption of the first ECU 10 connected to the sensor 30 can be suppressed.

[0031] In addition, the electronic control method according to the present embodiment is 10 The program is executed by a processor included in the ECU 20, and when the first ECU 10 and the second ECU 20 are in a sleep state, the first determination circuit 11 determines whether or not there is a change in the detection value of the sensor 30, and when it is determined that there is a change, an internal trigger is generated, and the second determination circuit 12 is started by the internal trigger. After that, the second determination circuit 12 obtains an input value by performing a filtering process on the detection value of the sensor 30, and determines whether or not there is a change in the input value, and when it is determined that there is a change, transmits a wake-up signal to the second ECU 20. This allows the first ECU 10 to determine whether or not there is a change in the detection value with low power consumption, and when there is a change in the detection value, it can start up the second ECU 20 with low power consumption. As a result, the power consumption of the first ECU 10 connected to the sensor 30 can be suppressed.

[0032] In the electronic control device according to this embodiment, when the second determination circuit 12 determines that the input value has changed, it stores the input value after the change as the previous value, and (Current value) The second determination circuit 12 compares the current value with the previous value to determine whether the input value has changed. This allows the second determination circuit 12 to detect the change in the detection value of the sensor 30 in two stages and activate the determination circuit according to the stage. As a result, the dark current can be reduced in two stages.

[0033] 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 is a change in the input value obtained by filtering the detection value of the sensor 30, and when it determines that there is a change, transmits a command for an event occurrence to the second ECU 20. In other words, the first ECU 10 does not need to periodically transmit the presence or absence of an event occurrence, but only needs to transmit a command for an event occurrence when there is a change in the input value. This makes it possible to reduce the power consumption of the first ECU 10.

[0034] In the electronic control device according to this embodiment, the first determination circuit 11 determines at a predetermined cycle whether or not there is a change in the detection value of the sensor 30. This allows the change in the detection value to be determined at a low clock, thereby reducing the power consumption of the first ECU 10.

[0035] In the electronic control device according to this embodiment, when the first determination circuit 11 determines that there is a change, it stores the detected value after the change as the previous value, and determines whether there is a change depending on whether the current detected value is within a predetermined range including the previous value. This makes it possible to determine whether there is a change in the detected value even if the input to the input port is an analog value.

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

[0037] In the electronic control device according to this embodiment, the first determination circuit 11 has a memory 111 for storing the detected value after the change as a previous value when it is determined that there is a change, a calculation circuit for calculating a predetermined range including the previous value, and a comparator 117 for comparing the detected value with a value calculated by the calculation circuit. This makes it possible to determine whether or not there is a change in the detected value even if the input to the input port is an analog value.

[0038] The above-described embodiments are described for the purpose of facilitating understanding of the present invention, and are not described for the purpose of limiting the present invention. Therefore, the elements disclosed in the above embodiments are 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 system 111 Memory 112 Addition Circuit 113 Subtraction Circuit 114 Selection circuit 115 Switching circuit 116 D / A Converter 117 Comparator 118 Control Decision Circuit

Claims

1. An electronic control device comprising: a first ECU connected to a sensor capable of detecting an object when a main switch is off, the first ECU having a first determination circuit that generates an internal trigger based on the detection value of the sensor, and a second determination circuit that is activated by the internal trigger; and a second ECU connected to the first ECU by a communication line, the first determination circuit being a circuit that can operate at a low speed when the first ECU is in a sleep state, and the second determination circuit being a circuit that is activated by the internal trigger generated by the first determination circuit and operates at a high speed 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 there has been a change in the detection value, and generates the internal trigger when it determines that there has been a change, and the second determination circuit, after being activated by the internal trigger, obtains an input value by filtering the detection value, determines whether or not there has been a change in the input value, and when it determines that there has been a change, sends a wake-up signal to the second ECU.

2. An electronic control device according to claim 1, wherein, when the second judgment circuit judges that the input value has changed, it stores the input value after the change as a previous value, and compares the input value with the previous value to judge whether or not the input value has changed.

3. An electronic control device according to claim 1 or 2, wherein, when the first ECU and the second ECU are in a normal startup state, the second determination circuit determines whether or not there has been a change in the input value obtained by filtering processing of the detected value, and if it determines that there has been a change, sends a command to the second ECU to generate an event.

4. An electronic control device according to claim 1 or 2, wherein the first determination circuit determines whether or not the detected value has changed at a predetermined cycle.

5. An electronic control device according to claim 1 or 2, wherein, when the first determination circuit determines that there has been a change, it stores the detected value after the change as a previous value, and determines whether there has been a change depending on whether the current detected value is within a predetermined range including the previous value.

6. An electronic control device according to claim 5, wherein the previous value is the median value of the predetermined range.

7. An electronic control device according to claim 5, wherein the first determination circuit determines that there has been a change when the current detected value is outside the predetermined range.

8. An electronic control device according to claim 1 or 2, wherein the second determination circuit transitions to a sleep state when it determines that there is no change in the input value.

9. An electronic control device according to claim 1 or 2, wherein the first judgment circuit has: a memory for storing the detected value after the change as a previous value when it judges that there has been a change; an arithmetic circuit for calculating a predetermined range including the previous value; and a comparator for comparing the detected value with the calculated value of the arithmetic circuit.

10. An electronic control method executed by a processor included in a first ECU, wherein the first ECU is connected to a sensor capable of detecting an object when a main switch is off and is connected to a second ECU by a communication line, and has a first judgment circuit that generates an internal trigger based on a detection value of the sensor, and a second judgment circuit that is activated by the internal trigger, wherein the first judgment circuit is a circuit that can operate at a low speed when the first ECU is in a sleep state, and the second judgment circuit is a circuit that is activated by the internal trigger generated by the first judgment circuit and operates at a high speed to perform filtering processing, and the processor, when the first ECU and the second ECU are in a sleep state, determines whether or not there has been a change in the detection value using the first judgment circuit, and generates the internal trigger when it determines that there has been a change, and after activating the second judgment circuit using the internal trigger, obtains an input value by filtering the detection value using the second judgment circuit, and determines whether or not there has been a change in the input value, and if it determines that there has been a change, sends a wake-up signal to the second ECU.