Electronic control device

Abstract

The ECU (20) includes a control unit (70) for controlling the cut-off circuit (50). The cut-off circuit (50) includes a cut-off circuit (50C) provided on the main line (41), cut-off circuits (50A1, 50B1) provided corresponding to the terminals (30A1, 30B1) connected to the power supply (10), and cut-off circuits (50A2, 50A3, 50B2, 50B3) provided corresponding to the terminals (30A2, 30A3, 30B2, 30B3) connected to the load (11). When at least one of the current flowing through the cut-off circuit (50) and the voltage of the power supply line (40) meets a specified abnormality detection condition, the control unit (70) controls a portion of the plurality of cut-off circuits (50A1, 50A2, 50A3, 50B1, 50B2, 50B3) and the cut-off circuit (50C) to be in a cut-off state.

Description

[0001] Cross-referencing of related applications This application is based on Japanese Patent Application No. 2023-186045, filed on October 31, 2023, and is incorporated herein by reference in its entirety. Technical Field

[0002] The disclosure in this specification relates to an electronic control device with power distribution function. Background Technology

[0003] Patent Document 1 discloses a power supply device (electronic control device) with power distribution function. The description of technical elements in this specification is based on prior art documents referenced by way of reference.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2020-120479 Summary of the Invention

[0005] The electronic control device in Patent Document 1 includes two switches disposed on wires connecting two power sources. The load is electrically connected to the wires at a position between the two switches. Therefore, if, for example, an abnormality such as a grounding occurs in the power line connecting the electronic control device and the power source, the switches malfunction (remaining closed), the power supply to the load cannot be maintained. In the above-mentioned viewpoint, or in other viewpoints not mentioned, further improvements are required to the electronic control device.

[0006] One of the disclosed objectives is to provide an electronic control device capable of maintaining a power supply to at least a portion of the load.

[0007] One disclosed embodiment is an electronic control device that receives power from multiple power sources and distributes power to multiple loads, wherein the electronic control device comprises: Terminals, including multiple power terminals electrically connected to multiple power sources and multiple load terminals electrically connected to multiple loads; Power wiring includes a main line that electrically connects a first power terminal, which is one of a plurality of power terminals, to a second power terminal, which is another of a plurality of power terminals, and a plurality of branch lines that electrically connect the main line to load terminals. Multiple disconnection circuits, respectively located on the main line and branch lines, are used to energize or disconnect the current supplied by the power source; and The control unit controls multiple disconnection circuits. The disconnection circuit includes a trunk disconnection circuit located on the trunk line and multiple terminal disconnection circuits located corresponding to the terminals. The terminal disconnect circuit includes: multiple load disconnect circuits, each disposed on a branch line corresponding to a load terminal; a first power disconnect circuit, disposed on a first trunk line (i.e., on the trunk line between the main disconnect circuit and the first power terminal) between the connection portion of the branch line and the first power terminal; and a second power disconnect circuit, disposed on a second trunk line (i.e., on the trunk line between the main disconnect circuit and the second power terminal) between the connection portion of the branch line and the second power terminal. When at least one of the current flowing through the disconnect circuit and the voltage of the power supply line meets the specified abnormality detection conditions, the control unit controls a portion of the multiple terminal disconnect circuits and the main line disconnect circuit to the disconnect state.

[0008] According to the disclosed electronic control device, even if the terminal disconnect circuit becomes uninterruptible in the event of an abnormality such as grounding, it can prevent the inability to supply power to all loads due to the disconnection of the main line disconnect circuit. That is, it can maintain power supply to at least a portion of the loads.

[0009] The various methods disclosed in this specification employ different technical means to achieve their respective purposes. The reference numerals enclosed in parentheses in the claims are used to illustratively indicate the correspondence with portions of the embodiments described later and are not intended to limit the scope of the technology. The purposes, features, and effects disclosed in this specification become clearer with reference to the following detailed description and the accompanying drawings. Attached Figure Description

[0010] Figure 1 This is a diagram showing the overall configuration of the ECU in the first embodiment.

[0011] Figure 2 This is a diagram illustrating an example of a circuit being cut off.

[0012] Figure 3 This is another example of a circuit being cut off.

[0013] Figure 4 This is another example of a circuit being cut off.

[0014] Figure 5 This is another example of a circuit being cut off.

[0015] Figure 6 This is a diagram representing the control unit.

[0016] Figure 7 This is a diagram showing the terminals of a microcomputer.

[0017] Figure 8 This is a graph representing the threshold.

[0018] Figure 9 This is a diagram showing the relationship between the detection of each latch and the abnormal mode.

[0019] Figure 10 This is a flowchart illustrating the INT_C interrupt handling process.

[0020] Figure 11 This is a flowchart representing post-cutting processing 1.

[0021] Figure 12 This is a flowchart representing the A3 / B3 output processing.

[0022] Figure 13 This is a flowchart illustrating the INT_A1 interrupt handling.

[0023] Figure 14 This is a flowchart illustrating the INT_A1H' interrupt handling.

[0024] Figure 15 This is a flowchart representing post-cutting processing 2.

[0025] Figure 16 This is a flowchart illustrating the INT_A1h interrupt handling.

[0026] Figure 17 This diagram illustrates an example of the operation when a ground fault occurs at terminal A3.

[0027] Figure 18 This diagram illustrates the action when a ground fault occurs at terminal A3.

[0028] Figure 19 This diagram illustrates an example of the operation when the circuit A3 cannot be disconnected due to a ground fault at terminal A3.

[0029] Figure 20 This diagram illustrates an example of the operation when a ground fault occurs at terminal A1.

[0030] Figure 21 This diagram illustrates the action when a ground fault occurs at terminal A1.

[0031] Figure 22 This diagram illustrates an example of the operation when the circuit A1 cannot be disconnected due to a ground fault at terminal A1.

[0032] Figure 23 This diagram illustrates an example of the operation when an open-circuit fault occurs at terminal A1.

[0033] Figure 24 This diagram illustrates the action when an open-circuit fault occurs at terminal A1.

[0034] Figure 25 This diagram illustrates an example of the action taken when a ground fault occurs due to a disconnection delay.

[0035] Figure 26 This diagram illustrates the action when a ground fault occurs due to a disconnection delay.

[0036] Figure 27 This diagram illustrates the operation of the control unit when a ground fault occurs.

[0037] Figure 28 This is a diagram showing a variation of the control unit.

[0038] Figure 29 This is a graph representing the threshold.

[0039] Figure 30 This is another diagram illustrating load.

[0040] Figure 31 This is a diagram showing the control unit in the ECU of the second embodiment.

[0041] Figure 32 This is a diagram showing the control unit in the ECU of the third embodiment.

[0042] Figure 33 This is a diagram showing the control unit in the ECU of the fourth embodiment.

[0043] Figure 34 This is a graph representing the threshold.

[0044] Figure 35 This is a diagram representing a variation.

[0045] Figure 36 This is a diagram representing a variation.

[0046] Figure 37 This is a diagram showing the power supply system of the ECU using the fifth embodiment.

[0047] Figure 38 This is a diagram representing the control unit.

[0048] Figure 39 This is a graph representing the threshold.

[0049] Figure 40 This is a diagram showing the conditions for cutting off a circuit.

[0050] Figure 41 This is a diagram illustrating an example of the action that occurs when a ground fault occurs.

[0051] Figure 42 This is a diagram illustrating an example of the action that occurs when a ground fault occurs. Detailed Implementation

[0052] Hereinafter, several embodiments will be described based on the accompanying drawings. Furthermore, the same reference numerals are used to denote corresponding components in each embodiment, thus sometimes omitting repeated descriptions. Even when only a portion of the configuration is described in each embodiment, the configurations of other previously described embodiments can be applied to the other parts of that configuration. Moreover, not only combinations of configurations explicitly shown in the descriptions of each embodiment, but also configurations of multiple embodiments can be partially combined with each other, even if not explicitly shown, as long as the combination does not particularly cause obstacles.

[0053] (First Implementation) The electronic control device of this embodiment has a power distribution function. Hereinafter, the electronic control device will be referred to as an ECU. ECU is an abbreviation for Electronic Control Unit. An ECU is, for example, mounted on a mobile body. The ECU receives power from multiple power sources mounted on the mobile body and distributes power to multiple devices mounted on the mobile body. Examples of mobile bodies include vehicles, aircraft, ships, construction machinery, and agricultural machinery. As an example, the ECU of this embodiment is mounted on a vehicle. The ECU is a power distribution ECU that integrates power distribution functions in a vehicle. For example, a regional ECU can also function as a power distribution ECU. A vehicle may have a power distribution ECU different from a regional ECU, or it may have a power distribution ECU in a configuration that does not have a regional ECU.

[0054] Furthermore, the regional ECUs, together with the central ECU (which acts as a higher-level ECU), vehicle-mounted devices, and communication lines, form the in-vehicle network system. This in-vehicle network system is a communication network based on a regional architecture, enabling efficient data exchange between the central ECU, multiple regional ECUs, and multiple vehicle-mounted devices. The regional ECUs control the vehicle-mounted devices based on instructions from the central ECU. The vehicle-mounted devices may include ECUs, actuators, and sensors located below the regional ECUs. The regional ECUs are configured in pre-defined areas within the vehicle. The regional ECUs have power distribution functions, supplying power to each vehicle-mounted device. The regional ECUs also have gateway functions, enabling mutual communication by converting and relaying data between networks with different communication methods. At least one of the multiple regional ECUs can also function as the aforementioned power distribution ECU.

[0055] <ecu> First, based on Figure 1 The overall configuration of the ECU will be described. As shown in Figure 1 The ECU 20 receives supply of electric power from a plurality of power supplies 10, and distributes electric power to a plurality of loads 11. The load 11 corresponds to the above-described vehicle-mounted device.

[0056] The power supply 10 that supplies electric power to the ECU 20 includes at least a power supply 10A and a power supply 10B. As an example, the power supply 10A (power supply A) of the present embodiment is a main power supply, and the power supply 10B (power supply B) is an auxiliary power supply that has a lower electric power supply capability than the power supply 10A. The power supply 10A corresponds to the first power supply, and the power supply 10B corresponds to the second power supply. The power supply 10B alone cannot supply electric power to all of the loads 11. The power supply 10A is, for example, a DCDC converter that steps down electric power supplied from a main battery and outputs the same. The power supply 10B is, for example, an auxiliary battery.

[0057] The load 11 includes a load that is electrically connected to the trunk line 41A in the trunk line 41 described later and a load that is electrically connected to the trunk line 41B. The load 11 can include a load that is electrically connected to both of the trunk line 41A and the trunk line 41B. As an example, the load 11 of the present embodiment includes a load 11A, a load 11B, and a load 11C. The load 11A (load A) is electrically connected to the trunk line 41A via a corresponding branch line 42. The load 11B (load B) is electrically connected to the trunk line 41B via a corresponding branch line 42. The load 11C (load C) is electrically connected to the trunk lines 41A and 41B, respectively. The plurality of loads 11 can communicate via a communication bus 12, for example.

[0058] The priority of electric power supply based on the ECU 20 of the load 11C is higher than that of the loads 11A and 11B. The priority of electric power supply based on the ECU 20 of the loads 11A and 11B is lower than that of the load 11C. The load 11C corresponds to the first load, and the loads 11A and 11B correspond to the second load. The priority of electric power supply in the plurality of loads 11 is set in advance. The priority is set, for example, in accordance with the importance of the function. It is also possible to set the load 11 that has an important function in terms of running, such as a safety-related function, as a load with high priority, and to set the load 11 that has a function other than this (a general function), that is, a non-safety-related function, as a load with low priority. It is also possible to set the load 11 that is redundantly configured as a load with high priority, and to set the load 11 that is not redundantly configured as a load with low priority. In a vehicle, an EPS device, a brake device, and the like are redundantly provided. EPS is an abbreviation for Electric Power Steering.

[0059] As an example, the load 11C of the present embodiment is an ECU that has a safety-related function. The load 11C is a redundantly configured load. The load 11C is, for example, an ECU that is redundantly configured in correspondence with a redundantly provided motor in an EPS device.

[0060] The ECU20 has multiple terminals 30, power wiring 40, multiple disconnect circuits 50, power circuit 60, and control unit 70.

[0061] Terminal 30 is an external connection terminal used to electrically connect ECU 20 to external devices. As an example, in this embodiment, terminal 30 includes terminals 30A1, 30A2, 30A3, 30B1, 30B2, and 30B3. Terminals 30A1 and 30B1 are so-called power terminals. Terminal 30A1 (A1 terminal) is electrically connected to power supply 10A via a power line. Terminal 30B1 (B1 terminal) is electrically connected to power supply 10B via a power line. Terminal 30A1 corresponds to a first power terminal, and terminal 30B1 corresponds to a second power terminal. As an example, in this embodiment, terminals 30A1 and 30B1 are connected to the corresponding power supplies 10A and 10B without passing through other devices (e.g., ECU).

[0062] Terminals 30A2, 30A3, 30B2, and 30B3 are load terminals used to output power from ECU20 to the corresponding load 11. Terminals 30A2 and 30B2 are electrically connected to load 11C via their respective power lines. Terminal 30A2 (A2 terminal) is connected via one of the power lines corresponding to the redundant configuration of load 11C, and terminal 30B2 (B2 terminal) is connected via the other corresponding power line corresponding to the redundant configuration of load 11C. Terminal 30A3 (A3 terminal) is electrically connected to load 11A via its corresponding power line. Terminal 30B3 (B3 terminal) is electrically connected to load 11B via its corresponding power line.

[0063] Multiple terminals 30 are mounted on a printed circuit board, for example, as connectors. These terminals 30 can be grouped together in one connector or distributed across multiple connectors. As mentioned above, the load 11C is redundantly configured, therefore the corresponding terminals 30A2 and 30B2 are also redundantly configured. For example, the number of terminals 30A2 and 30B2 (pin counts) is equal to each other, and their structures are also approximately equal.

[0064] Power wiring 40 electrically connects multiple terminals 30. Power wiring 40 provides the power grid. Power wiring 40 includes a main line 41 and multiple branch lines 42. The main line 41 electrically connects the power terminals. The main line 41 is the power wiring connecting terminals 30A1 and 30B1. The main line 41 forms the main backbone of the power grid. The main line 41 may be referred to as the backbone, etc.

[0065] The trunk line 41 includes trunk lines 41A and 41B. Trunk line 41A (trunk line A) is the portion of trunk line 41 from terminal 30A1 to the disconnection circuit 50C (described later). Trunk line 41B (trunk line B) is the portion of trunk line 41 from terminal 30B1 to the disconnection circuit 50C. Trunk line 41A is the portion of trunk line 41 on the terminal 30A1 side, and trunk line 41B is the portion of trunk line 41 on the terminal 30B1 side. Trunk line 41A corresponds to the first trunk line, and trunk line 41B corresponds to the second trunk line.

[0066] Branch lines 42 electrically connect each load terminal to the main line 41. Branch lines 42 individually connect load terminals to the main line 41. Power wiring 40 includes branch lines 42 connected to the main line 41A and branch lines 42 connected to the main line 41B. As an example, the power wiring 40 of this embodiment includes two branch lines 42 connected to the main line 41A and two branch lines 42 connected to the main line 41B. One of the branch lines 42 connected to the main line 41A is connected to terminal 30A2, and the other is connected to terminal 30A3. One of the branch lines 42 connected to the main line 41B is connected to terminal 30B2, and the other is connected to terminal 30B3.

[0067] The power supply wiring 40 may be configured to include wiring formed on a printed circuit board, for example. The power supply wiring 40 may also be configured to include the above-described wiring and wiring components such as a metal plate mounted on the printed circuit board.

[0068] A disconnect circuit 50 is provided on the power supply line 40 to energize or disconnect the current flowing through the power supply line 40. The disconnect circuit 50 disconnects the electrical connection with the power supply 10. The disconnect circuit 50 is provided on the main line 41 and the branch line 42 respectively. As an example, the disconnect circuit 50 in this embodiment includes disconnect circuits 50A1, 50A2, 50A3, 50B1, 50B2, 50B3, and 50C.

[0069] A disconnect circuit 50C (disconnect circuit C) is installed on trunk line 41. Disconnect circuit 50C is equivalent to a trunk line disconnect circuit. Trunk line 41A is connected to disconnect circuit 50C. Trunk line 41B is connected to disconnect circuit 50C. Disconnect circuit 50C electrically disconnects trunk lines 41A and 41B in the disconnected (open) state. Disconnect circuit 50C electrically connects trunk lines 41A and 41B in the connected (on) state. Disconnect circuit 50C is sometimes referred to as an isolator, backbone switch, etc.

[0070] Disconnecting circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 are configured corresponding to terminals 30. Disconnecting circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 are equivalent to terminal disconnecting circuits. Disconnecting circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 connect or disconnect the corresponding terminals 30 from the power supply wiring 40.

[0071] A disconnect circuit 50A1 (disconnect circuit A1) is located near terminal 30A1 in the main line 41A. Disconnect circuit 50A1 is equivalent to a first power disconnect circuit. Disconnect circuit 50A1 is located in the main line 41A between the connection point of branch line 42 and terminal 30A1. That is, branch line 42 is connected to the main line 41A between disconnect circuit 50A1 and disconnect circuit 50C. In the disconnected state, disconnect circuit 50A1 electrically disconnects the portion of the main line 41 closer to disconnect circuit 50C than disconnect circuit 50A1 from terminal 30A1 (power supply 10A).

[0072] A disconnect circuit 50B1 (disconnect circuit B1) is disposed on the main line 41B near terminal 30B1. Disconnect circuit 50B1 is equivalent to a second power disconnect circuit. Disconnect circuit 50B1 is disposed on the main line 41B between the connection point of branch line 42 and terminal 30B1. That is, branch line 42 is connected to the main line 41B between disconnect circuit 50B1 and disconnect circuit 50C. In the disconnected state, disconnect circuit 50B1 electrically disconnects the portion of the main line 41 closer to disconnect circuit 50C than disconnect circuit 50B1 from terminal 30B1 (power supply 10B).

[0073] Disconnection circuits 50A2, 50A3, 50B2, and 50B3 are equivalent to load disconnection circuits. Disconnection circuit 50A2 (disconnection circuit A2) is provided on branch line 42 connecting main line 41A and terminal 30A2. Disconnection circuit 50A2 is located near terminal 30A2 on the corresponding branch line 42. In the disconnected state, disconnection circuit 50A2 electrically disconnects terminal 30A2 from main line 41A. Disconnection circuit 50B2 (disconnection circuit B2) is provided on branch line 42 connecting main line 41B and terminal 30B2. Disconnection circuit 50B2 is located near terminal 30B2 on the corresponding branch line 42. In the disconnected state, disconnection circuit 50B2 electrically disconnects terminal 30B2 from main line 41B. As an example, in this embodiment, disconnection circuit 50A2 electrically disconnects one of the redundant components of load 11C from main line 41A in the disconnected state. When the disconnect circuit 50B2 is in the disconnected state, it electrically disconnects the redundant component of the load 11C from the main line 41B.

[0074] A disconnect circuit 50A3 (disconnect circuit A3) is installed on branch line 42 connecting main line 41A and terminal 30A3. Disconnect circuit 50A3 is located near terminal 30A3 on the corresponding branch line 42. In the disconnected state, disconnect circuit 50A3 electrically disconnects terminal 30A3 from main line 41A. A disconnect circuit 50B3 (disconnect circuit B3) is installed on branch line 42 connecting main line 41B and terminal 30B3. Disconnect circuit 50B3 is located near terminal 30B3 on the corresponding branch line 42. In the disconnected state, disconnect circuit 50B3 electrically disconnects terminal 30B3 from main line 41B.

[0075] The cut-off circuit 50 is configured, for example, to include electronic components mounted on a printed circuit board. The cut-off circuit 50 has a switch, a drive unit (drive circuit) for driving the switch, and a current detection unit. Hereinafter, the direction of the current flowing in each cut-off circuit 50 toward the nearby terminal 30 will be defined as the positive direction, and the direction toward the side opposite to the terminal 30 will be defined as the negative direction. Figure 1 The directions indicated by the solid arrows are all positive directions. The detailed configuration of the cut-off circuit 50 will be described later.

[0076] The power supply circuit 60 is an internal power supply circuit located within the ECU 20. The power supply circuit 60 generates a constant voltage lower than the supply voltage based on the voltage supplied from the power supply 10. The power supply circuit 60 generates the operating voltage (e.g., 5V) for the control unit 70 and outputs it to the control unit 70. In addition to the power supply circuit 60, the ECU 20 also includes diodes 61 and 62, capacitor 63, voltage divider circuits 64 and 65, and a communication IC 66. The power supply circuit 60, diodes 61 and 62, capacitor 63, voltage divider circuits 64 and 65, and communication IC 66 are configured, for example, to include electronic components mounted on a printed circuit board. In addition to the electronic components, wiring on the printed circuit board may also be included.

[0077] Diodes 61 and 62 are configured in the wiring that electrically connects power supply 10 to power supply circuit 60 to prevent reverse current. Diodes 61 and 62 are configured such that their anodes are on the power supply 10 side. The anode of diode 61 is connected to main line 41A between terminal 30A1 and disconnect circuit 50A1. The anode of diode 62 is connected to main line 41B between terminal 30B1 and disconnect circuit 50B1.

[0078] Capacitor 63 is connected to the wiring that electrically connects power supply 10 and power circuit 60. Capacitor 63 is connected to the wiring between the cathodes of diodes 61 and 62. The positive terminal of capacitor 63 is connected to the wiring, and the negative terminal is grounded.

[0079] Voltage divider circuit 64 is used to detect the voltage of main line 41A. Voltage divider circuit 65 is used to detect the voltage of main line 41B. Control unit 70 monitors the voltage Va after voltage division by resistors in voltage divider circuit 64 and the voltage Vb after voltage division by resistors in voltage divider circuit 65. Communication IC 66 is a circuit for ECU 20 (control unit 70) to communicate with other devices, such as other ECUs, via communication bus 12.

[0080] The control unit 70 controls the disconnect circuit 50. The control unit 70 controls the operation (on / off) of the switches included in the disconnect circuit 50. The control unit 70 acquires the aforementioned voltages Va and Vb, and controls the disconnect circuit 50 based on the voltages Va and Vb. The control unit 70 acquires the current detected by the disconnect circuit 50, and controls the disconnect circuit 50 based on the current. Figure 1 As shown, the control unit 70 obtains current Ia1 from the cut-off circuit 50A1 and current Ib1 from the cut-off circuit 50B1. The control unit 70 obtains current Ia2 from the cut-off circuit 50A2 and current Ib2 from the cut-off circuit 50B2. The control unit 70 obtains current Ia3 from the cut-off circuit 50A3 and current Ib3 from the cut-off circuit 50B3.

[0081] The control unit 70 is configured, for example, to include electronic components mounted on the printed circuit board and wiring formed on the printed circuit board. In addition to the function of detecting anomalies based on voltage and current, the control unit 70 also has a latching function to retain anomaly detection data. Detailed configuration of the control unit 70 will be described later.

[0082] <Disconnecting the circuit> Next, based on Figures 2-5 The structure of the cut-off circuit is explained. Figure 2 This represents an example of cutting off a circuit. Figure 3 This is another example of cutting off a circuit. Figure 4 This is another example of cutting off a circuit. Figure 5 This is another example of cutting off a circuit. Figures 2-5 The solid arrows indicate the direction of the current that can be cut off by each MOSFET.

[0083] For example, the disconnect circuit 50C can be used Figure 2 , Figure 3 as well as Figure 4 Any of the components in it. For example, the cut-off circuit 50A1 can employ... Figure 2 , Figure 3 , Figure 4 as well as Figure 5 Any of the following configurations. The remaining disconnect circuits 50A2, 50A3, 50B1, 50B2, and 50B3 can, for example, employ... Figure 5 The structure shown. In Figures 2-4 As an example, the cutoff circuit 50C is shown in the diagram. Figure 5 As an example, the cut-off circuit 50A2 is shown.

[0084] Figure 2 The cutoff circuit 50C shown includes n-channel MOSFETs 51 and 52, diodes 53 and 54, driving units 55 and 56, and a current sensing unit 57. MOSFET is an abbreviation for Metal Oxide Semiconductor Field Effect Transistor. MOSFETs 51 and 52 are equivalent to the switches described above. The cutoff circuit 50C is a source-shared type cutoff circuit where the sources of two MOSFETs 51 and 52 are connected together. Diodes 53 and 54 are parasitic diodes of the corresponding MOSFETs 51 and 52. Diode 53 is connected in reverse parallel with the corresponding MOSFET 51. Diode 54 is connected in reverse parallel with the corresponding MOSFET 52. The anodes of diodes 53 and 54 are connected to the sources of the corresponding MOSFETs 51 and 52, and their cathodes are connected to the drains.

[0085] The drive units 55 and 56 are sometimes referred to as drivers. The drive units 55 and 56 are input with a common control signal (gate drive signal). When an off-state signal (L level) is input, the drive units 55 and 56 turn off MOSFETs 51 and 52. A current sensing unit 57 is disposed outside the series circuit based on MOSFETs 51 and 52. The current sensing unit 57 may, for example, include a shunt resistor to obtain a voltage value corresponding to the current.

[0086] By reversing the diodes 53 and 54, bidirectional current flow can be prevented by disconnecting both MOSFETs 51 and 52. Diode 53 interrupts the current flowing from the drain to the source of MOSFET 51, i.e., from MOSFET 51 to MOSFET 52. Diode 54 interrupts the current flowing from the drain to the source of MOSFET 52, i.e., from MOSFET 52 to MOSFET 51. On the other hand, when an on signal (a signal at level H) is input, the cutoff circuit 50C becomes energized, allowing current to flow in both directions—one from MOSFET 51 to MOSFET 52 and the other from MOSFET 52 to MOSFET 51—that is, bidirectional current. This allows for the energization or interruption of bidirectional current.

[0087] like Figure 3 As shown, the current sensing unit 57 can also be disposed between MOSFETs 51 and 52. The current sensing unit 57 is disposed between the source of MOSFET 51 and the source of MOSFET 52. Other configurations are similar. Figure 2 The example shown is the same. In Figure 3 The configuration shown also allows for the energization or interruption of bidirectional current.

[0088] like Figure 4 As shown, it can also be configured as a drain-shared cutoff circuit. MOSFETs 51 and 52 have their drains connected together. Other configurations are the same as... Figure 2 The example is the same. In this configuration, diodes 53 and 54 are also reverse-biased. Therefore, by disconnecting both MOSFETs 51 and 52, bidirectional current flow can be prevented. Alternatively, by turning on both MOSFETs 51 and 52, bidirectional current can be passed through. Although the diagram is omitted, it is also possible to... Figure 4 In the configuration shown, the current sensing unit 57 is disposed between the drains of MOSFETs 51 and 52.

[0089] Figure 5 The cutoff circuit 50A2 shown includes a MOSFET 51, a diode 53, a drive unit 55, and a current detection unit 57. Similar to the configuration described above, the diode 53 and MOSFET 51 are connected in reverse parallel. The anode of the MOSFET 51 and diode 53 are connected to the source, and the cathode is connected to the drain. The MOSFET 51 is configured such that its drain is inside the ECU 20, and its source is outside the ECU 20. The current detection unit 57 is connected to the source of the MOSFET 51.

[0090] The cutoff circuit 50A2 cuts off the current flowing from the drain of MOSFET 51 towards its source, i.e., from inside the ECU 20 towards the outside, by turning off MOSFET 51. Turning off MOSFET 51 also cuts off the current flowing from the cutoff circuit 50 towards the corresponding terminal 30.

[0091] Furthermore, the switch included in the cut-off circuit 50 can be replaced by a switch without a parasitic diode, such as an IGBT or a normally-on switch. IGBT is an abbreviation for Insulated Gate Bipolar Transistor. When using a switch without a parasitic diode, for example, the cut-off circuit 50C can be constructed using only one switch.

[0092] <Control Department> Next, based on Figures 6-8 The structure of the control unit 70 will be explained. Figure 6 This indicates the control unit 70. Figure 7 The terminals of the microcomputer 71 are shown. Figure 8 The threshold is shown.

[0093] The control unit 70 includes arithmetic processing circuitry comprising a processor, memory, and storage. The processor executes various processes to implement its functions by accessing the memory. The memory is, for example, RAM (Random Access Memory). Storage includes non-volatile storage media such as flash memory. Control programs executed by the processor are stored in the storage. The processor executing the control program is equivalent to executing the control method corresponding to the control program.

[0094] As an example, the control unit 70 in this embodiment includes a microcomputer 71, a DAC 72, multiple comparators 73, multiple latches 74, and multiple logic gates. DAC is an abbreviation for Digital to Analog Converter.

[0095] The microcomputer 71 includes a CPU, RAM, ROM, and an A / D converter. CPU is an abbreviation for Central Processing Unit. ROM is an abbreviation for Read Only Memory. For example... Figure 7 As shown, the microcomputer 71 has multiple terminals. The terminals include an ADin terminal, an INT terminal, a PT terminal, and a COMn terminal.

[0096] The ADin terminal is used to input the voltages Va, Vb, and currents Ia1, Ia2, Ia3, Ib1, Ib2, Ib3, and Ic. The ADin terminal is used to monitor voltage and current. The INT terminal is used to input the value output by latch 74. The INT terminal is an interrupt request terminal. The PT terminal includes terminals that output control signals for the switches (MOSFETs) constituting the cutoff circuit 50. The PT terminal includes terminals that output signals for clearing latch 74 and for setting DAC 72. The communication terminal COMn is an input / output terminal used for communication with external devices via the communication IC 66.

[0097] DAC72 performs D / A conversion on the set value output from microcomputer 71 and outputs it as a threshold to each comparator 73. Comparator 73 compares the detected voltage or current value with the threshold and outputs the comparison result. Comparator 73 detects anomalies such as grounding and overvoltage. Comparator 73 includes comparators 73A1, 73A2, 73A3, 73B1, 73B2, and 73B3. These comparators 73A1, 73A2, 73A3, 73B1, 73B2, and 73B3 detect grounding based on the current flowing through the cutoff circuit 50, for example.

[0098] The comparison results of comparator 73A1 output current Ia1 with the threshold. The comparison results of comparator 73A2 output current Ia2 with the threshold. The comparison results of comparator 73A3 output current Ia3 with the threshold. The comparison results of comparator 73B1 output current Ib1 with the threshold. The comparison results of comparator 73B2 output current Ib2 with the threshold. The comparison results of comparator 73B3 output current Ib3 with the threshold. Figure 6 In the example shown, the threshold is input to the inverting input terminals of comparators 73A1, 73A2, 73A3, 73B1, 73B2, and 73B3, while the current value is input to the non-inverting input terminals.

[0099] Figure 8 This represents an example of a set threshold. In Figure 8 The threshold for grounding detection, the overcurrent threshold, and the normal operating current range are shown. The detection value of the current detection unit 57 is a positive (+) value when the current flows in the positive direction, and a negative (-) value when the current flows in the negative direction. The grounding detection threshold is set between the overcurrent threshold and the normal operating current range. As will be described later, grounding refers to grounding outside terminal 30 or grounding generated by terminal 30. The outside of terminal 30 is, for example, the power line connecting terminal 30 to power supply 10, or the power line connecting terminal 30 to load 11. For convenience, grounding generated outside terminal 30 will sometimes be referred to as grounding of terminal 30 as grounding of terminal 30.

[0100] As an example, in this embodiment, the grounding detection threshold for current Ia1 is set to also be capable of open-circuit detection. That is, a threshold that can be used for both open and open circuit detection is set. The current Ia1 flowing in an open circuit is approximately zero (0), so a negative value close to zero is set. In this embodiment, the power supply capacity of power supply 10B is lower than that of power supply 10A, and power supply 10B may also be charged by power supplied from power supply 10A. An open circuit in terminal 30A1 refers, for example, to an open circuit generated in the power line connecting terminal 30A1 and power supply 10A.

[0101] Comparator 73 also includes comparators 73AH1, 73AH2, 73VA1, 73VA2, 73VB1, and 73VB2. Comparators 73AH1 and 73AH2 detect voltage anomalies (overvoltages) from a high-capacity power supply of 10A. Both comparators 73AH1 and 73AH2 are input voltage Va. The threshold set for comparator 73AH2 is higher than the threshold set for comparator 73AH1. Therefore, comparator 73AH2 outputs a signal indicating an anomaly (H level) with a delay compared to comparator 73AH1. Consequently, the timing of the latch is also delayed. Figure 6 In the example shown, the threshold is input to the inverting input terminals of comparators 73AH1 and 73AH2, and the voltage value is input to the non-inverting input terminal.

[0102] Comparators 73VA1 and 73VA2, for example, detect a decrease in voltage Va caused by grounding. Both comparators 73VA1 and 73VA2 are input with voltage Va. The threshold set for comparator 73VA2 is lower than the threshold set for comparator 73VA1. Therefore, comparator 73VA2 outputs a signal indicating an abnormal H level, delayed compared to comparator 73VA1. Similarly, comparators 73VB1 and 73VB2 detect a decrease in voltage Vb. Both comparators 73VB1 and 73VB2 are input with voltage Vb. The threshold set for comparator 73VB2 is lower than the threshold set for comparator 73VB1. Therefore, comparator 73VB2 outputs a signal indicating an abnormal H level, delayed compared to comparator 73VB1.

[0103] exist Figure 6 In the example shown, the threshold values ​​are input to the non-inverting input terminals of comparators 73VA1, 73VA2, 73VB1, and 73VB2, while the voltage values ​​are input to the inverting input terminals. As an example, in this embodiment, the threshold values ​​of comparators VA1 and VB1 are common (equal values). The threshold values ​​of comparators VA2 and VB2 are also common.

[0104] Latch 74 holds the data. As an example, the latch 74 in this embodiment is an SR latch. A PT terminal (PT_LC) is electrically connected to the R terminal of each latch 74, which outputs a signal for clearing the data in the latch 74. The latches 74 include latches 74A1, 74A2, 74A3, 74B1, 74B2, 74B3, and 74C.

[0105] To perform open-circuit detection, the S-terminal of latch 74A1 is input to the output signal of comparator 73A1. The S-terminal of latch 74A2 is input to the output signal of gate circuit 75A2. Gate circuit 75A2 is an AND gate, and its input terminals are input to the output signals of comparators 73A2 and 73VA1. Similarly, the S-terminal of latch 74A3 is input to the output signal of gate circuit 75A3. Gate circuit 75A3 is an AND gate, and its input terminals are input to the output signals of comparators 73A3 and 73VA1.

[0106] The S-terminal of latch 74B1 is input to the output signal of the corresponding gate circuit 75B1. Gate circuit 75B1 is an AND gate, and its input terminals are input to the output signals of comparators 73B1 and 73VB1. Similarly, the S-terminal of latch 74B2 is input to the output signal of the corresponding gate circuit 75B2. Gate circuit 75B2 is an AND gate, and its input terminals are input to the output signals of comparators 73B2 and 73VB1. The S-terminal of latch 74B3 is input to the output signal of the corresponding gate circuit 75B3. Gate circuit 75B3 is an AND gate, and its input terminals are input to the output signals of comparators 73B3 and 73VB1.

[0107] The latch 74 also includes latches 74AH1 and 74AH2. The S-terminal of latch 74AH1 is input to the output signal of the corresponding comparator 73AH1. Similarly, the S-terminal of latch 74AH2 is input to the output signal of the corresponding comparator 73AH2.

[0108] Latch 74A1 outputs signal A1b. Latch 74A2 outputs signal A2b. Latch 74A3 outputs signal A3b. Latch 74B1 outputs signal B1b. Latch 74B2 outputs signal B2b. Latch 74B3 outputs signal B3b. Latch 74AH1 outputs signal A1hb. Latch 74AH2 outputs signal A1hb'. These signals are input to the corresponding INT terminals of the microcomputer 71.

[0109] The gate circuits also include gate circuits 76A1, 76A2, 76A3, 76B1, 76B2, 76B3, and 76C. Gate circuits 76A1, 76A2, 76A3, 76B1, 76B2, 76B3, and 76C are AND gates, with a NOT gate connected to one of their input terminals. The output signals of gate circuits 76A1, 76A2, 76A3, 76B1, 76B2, 76B3, and 76C are input to the driving section of the corresponding cutoff circuit 50.

[0110] Gate circuit 76A1 is input to the inverted signal of A1b and the output signal of gate circuit 771. Gate circuit 771 is also an AND gate, with a NOT gate connected to one of its input terminals. Gate circuit 771 is input to the control signal of the cut-off circuit 50A1 output from the microcomputer 71 and the inverted signal of A1hb. When at least one of the following conditions is met—the control signal is at level L, the A1b signal is at level H, and the A1hb signal is at level H—gate circuit 76A1 outputs a disconnect signal (at level L) to the cut-off circuit 50A1 (switch) to set it to the cut-off state. For example, when the A1b signal becomes at level H due to grounding or an open circuit, gate circuit 76A1 outputs a disconnect signal to the cut-off circuit 50A1. When the A1hb signal becomes at level H due to overvoltage, gate circuit 76A1 outputs a disconnect signal to the cut-off circuit 50A1.

[0111] Gate circuit 76A2 is input with the inverted signal of A2b and the control signal of the cut-off circuit 50A2 output from microcomputer 71. When the control signal is at level L and / or the A2b signal is at level H, gate circuit 76A2 outputs a cut-off signal to the cut-off circuit 50A2. For example, when the A2b signal becomes at level H due to grounding, gate circuit 76A2 outputs a cut-off signal to the cut-off circuit 50A2.

[0112] Gate circuit 76A3 is input to the inverted signal of A3b and the output signal of gate circuit 772. Gate circuit 772 is an AND gate with a NOT gate connected to one of its input terminals. Gate circuit 772 is input to the control signal of the cut-off circuit 50A3 output from microcomputer 71 and the inverted signal of A3b'. A3b' is the A1b' signal output from gate circuit 773. Gate circuit 773 is an OR gate, and gate circuit 773 is input to the A1b and A1hb signals. When at least one of the following conditions is met—the control signal is at level L, the A3b signal is at level H, the A1b signal is at level H, and the A1hb signal is at level H—gate circuit 76A3 outputs a disconnect signal to the cut-off circuit 50A3.

[0113] For example, when signal A3b becomes H level due to grounding, gate circuit 76A3 outputs a disconnect signal to disconnect circuit 50A3. When signal A1hb becomes H level due to overvoltage, gate circuit 76A3 outputs a disconnect signal to disconnect circuit 50A3. When signal A1b becomes H level due to grounding or an open circuit, gate circuit 76A3 outputs a disconnect signal to disconnect circuit 50A3.

[0114] Gate circuit 76B1 is input to the inverted signal of B1b and the control signal of the cutoff circuit 50B1 output from the microcomputer 71. When the control signal is at level L and / or the B1b signal is at level H, gate circuit 76B1 outputs a cutoff signal to the cutoff circuit 50B1. Therefore, for example, when the B1b signal becomes at level H due to grounding, gate circuit 76B1 outputs a cutoff signal to the cutoff circuit 50B1. Similarly, gate circuit 76B2 is input to the inverted signal of B2b and the control signal of the cutoff circuit 50B2 output from the microcomputer 71. When the control signal is at level L and / or the B2b signal is at level H, gate circuit 76B2 outputs a cutoff signal to the cutoff circuit 50B2. For example, when the B2b signal becomes at level H due to grounding, gate circuit 76B2 outputs a cutoff signal to the cutoff circuit 50B2.

[0115] Gate circuit 76B3 is input to the inverted signal of B3b and the output signal of gate circuit 774. Gate circuit 774 is an AND gate with a NOT gate connected to one of its input terminals. Gate circuit 774 is input to the control signal of the cut-off circuit 50B3 output from the microcomputer 71 and the inverted signal of B3b'. B3b' is the output signal of gate circuit 775. Gate circuit 775 is an OR gate, and is input to A1b' and Cb'. Cb' is the output signal of gate circuit 776. Gate circuit 776 is an OR gate, and is input to Cb and A1hb'. When at least one of the following conditions is met—control signal at level L, B3b signal at level H, Cb signal at level H, A1hb' signal at level H, A1b signal at level H, and A1hb signal at level HH—gate circuit 76B3 outputs a disconnect signal to the cut-off circuit 50B3.

[0116] For example, when the B3b signal becomes high level due to grounding, gate circuit 76B3 outputs a disconnect signal to the cutoff circuit 50B3. When voltage Va and / or voltage Vb decreases due to grounding, and the Cb signal becomes high level, gate circuit 76B3 outputs a disconnect signal to the cutoff circuit 50B3. When the A1hb signal becomes high level due to overvoltage, gate circuit 76B3 outputs a disconnect signal to the cutoff circuit 50B3. When the A1b signal becomes high level due to grounding, gate circuit 76B3 outputs a disconnect signal to the cutoff circuit 50B3.

[0117] Gate circuit 76C is input to the inverted signal of the Cb signal and the output signal of gate circuit 777. Gate circuit 777 is an AND gate with a NOT gate connected to one of its input terminals. Gate circuit 777 is input to the control signal of the cut-off circuit 50C output from the microcomputer 71 and the inverted signal of the A1hb' signal. Gate circuit 76C outputs a disconnect signal to the cut-off circuit 50C when at least one of the following conditions is met: the control signal is at level L, the A1hb' signal is at level H, and the Cb signal is at level H. For example, when voltage Va and / or voltage Vb decreases due to grounding, and the Cb signal becomes at level H, gate circuit 76C outputs a disconnect signal to the cut-off circuit 50C. When the A1hb' signal becomes at level H due to overvoltage, gate circuit 76C outputs a disconnect signal to the cut-off circuit 50C.

[0118] <Latch detection and abnormal modes> Figure 9 This is an example illustrating the relationship between each latch's detection and abnormal modes. Specifically, it shows the relationship between the state of the signals output from each latch 74 and input to the INT terminal of the microcomputer 71, and the abnormal modes detected by the microcomputer 71. Figure 9 The diagram also shows the status of the A3b' and B3b' signals used to cut off power supply to low-priority loads 11A and 11B via hardware processing.

[0119] like Figure 9 As shown, when the A1b signal obtained from the INT_A1 terminal is at level H and the Cb signal obtained from the INT_C terminal is at level L, the microcomputer 71 detects that terminal 30A1 (A1 terminal) is open. Since the A1b signal is at level H, the A3b' and B3b' signals are also at level H.

[0120] When both the A1b and Cb signals are at high level, the microcomputer 71 detects that terminal 30A1 is grounded. Since the A1b and Cb signals are at high level, the A3b' and B3b' signals are also at high level.

[0121] When the A3b signal and Cb signal obtained from the INT_A3 terminal are both at high level (H), the microcomputer 71 detects that terminal 30A3 (A3 terminal) is grounded. In this case, the A3b' signal becomes low level (L level), the Cb signal becomes high level (H level), and therefore the B3b' signal becomes high level (H level). Similarly, when the A2b signal and Cb signal obtained from the INT_A2 terminal are both at high level (H level), the microcomputer 71 detects that terminal 30A2 (A2 terminal) is grounded. In this case, the A3b' signal becomes low level (L level), the Cb signal becomes high level (H level), and therefore the B3b' signal becomes high level (H level).

[0122] When the B1b signal and Cb signal obtained from the INT_B1 terminal are both at high level (H), the microcomputer 71 detects that terminal 30B1 (B1 terminal) is grounded. In this case, the A3b' signal becomes low level (L level), the Cb signal becomes high level (H level), and therefore the B3b' signal becomes high level (H level). When the B3b signal and Cb signal obtained from the INT_B3 terminal are both at high level (H), the microcomputer 71 detects that terminal 30B3 (B3 terminal) is grounded. In this case, the A3b' signal becomes low level (L level), the Cb signal becomes high level (H level), and therefore the B3b' signal becomes high level (H level). When the B2b signal and Cb signal obtained from the INT_B2 terminal are both at high level (H level), the microcomputer 71 detects that terminal 30B2 (B2 terminal) is grounded. In this case, the A3b' signal becomes low level (L level), the Cb signal becomes high level (H level), and therefore the B3b' signal becomes high level (H level).

[0123] When the A1hb signal obtained from the INT_A1hb terminal is at level H and the A1hb' signal obtained from the INT_A1hb' terminal is at level H, the microcomputer 71 detects that terminal 30A1 (A1 terminal) is under overvoltage, that is, the voltage supplied from power supply 10A is under overvoltage (high voltage). In this case, the A1hb signal is at level H, therefore the A3b' signal is at level H; since both the A1hb and A1hb' signals are at level H, therefore the B3b' signal is at level H.

[0124] <Control Methods> Next, based on Figures 10-16 The processing, i.e., control method, executed by the microcomputer 71 (processor) will be described. When the microcomputer 71 receives an interrupt request while the circuit 50 is fully powered on, it executes the following processing. Figure 10 The INT_C interrupt handling is shown. The H level of the signal is equivalent to 1, and the L level is equivalent to 0 (zero). Hereinafter, the H level may sometimes be represented as 1, and the L level as 0.

[0125] When the INT terminal (INT_C) of the disconnect circuit 50C is input with a Cb signal of high level, the microcomputer 71 executes INT_C interrupt processing. Additionally, when the voltage Va decreases below the threshold, the output of comparator 73VA2 becomes high level, consequently the output of gate circuit 75C becomes high level, and the Cb signal output from latch 74C also becomes high level. Similarly, when the voltage Vb decreases below the threshold, the output of comparator 73VB2 becomes high level, consequently the output of gate circuit 75C becomes high level, and the Cb signal output from latch 74C also becomes high level. Thus, when at least one of the voltages Va or Vb is below the threshold, the Cb signal becomes high level.

[0126] like Figure 10 As shown, firstly, the microcomputer 71 outputs an L-level signal as a control signal from the PT terminal (PT_C) corresponding to the cutoff circuit 50C (step S100). Consequently, the output of gate circuit 777 becomes L-level, so even if the Cb signal, which is the main cause of this interruption, is subsequently latched and cleared, changing from H-level to L-level, gate circuit 76C can maintain an L-level disconnect signal (for the cutoff state) for the cutoff circuit 50C. Next, the microcomputer 71 executes the post-cutoff processing 1 (step S101) after outputting a cutoff instruction to the cutoff circuit 50C. When post-cutoff processing 1 ends, the microcomputer 71 terminates the series of processes.

[0127] Figure 11 This indicates post-cutoff processing 1. The microcomputer 71 first determines whether both voltages Va and Vb have decreased (step S110). The microcomputer 71 compares the values ​​of voltages Va and Vb obtained via the corresponding ADin terminals (AD_VA, AD_VB) with pre-stored thresholds to determine whether voltages Va and Vb are below the threshold, i.e., whether they have decreased. The threshold is, for example, a value common to both voltages Va and Vb (an equal value).

[0128] When voltages Va and Vb decrease, the microcomputer 71 determines whether the transient counter has overflowed (step S111). If it overflows, an exception flag is set (step S112), and the process proceeds to the A3 / B3 output processing described later (step S121). If it does not overflow, the transient counter is incremented by 1 (step S113), and after a specified standby time (step S114), the processing after step S110 is executed again.

[0129] If the determination in step S110 is negative, the microcomputer 71 determines whether either voltage Va or Vb is below a threshold, i.e., whether either voltage Va or Vb has decreased (step S115). If either voltage Va or Vb has decreased, it determines whether the current on the decreased side is abnormal (step S116). The microcomputer 71 compares the values ​​of currents Ia1, Ia2, Ia3, Ib1, Ib2, and Ib3 obtained through the corresponding ADin terminal with pre-stored thresholds to determine whether the current exceeds the threshold, i.e., whether there is an abnormality. For example, if voltage Va decreases, it determines whether the currents Ia1, Ia2, and Ia3 on the trunk line 41A side are abnormal. When voltage Vb decreases, it determines whether the currents Ib1, Ib2, and Ib3 on the trunk line 41B side are abnormal.

[0130] If there is no current abnormality on the reduced side, proceed to step S118. If there is a current abnormality on the reduced side, the microcomputer 71 outputs an L-level control signal from the PT terminal corresponding to the cutoff circuit 50 that detected the current abnormality, and waits for a specified time (step S117). For example, if the current Ia3 exceeds a threshold, the microcomputer 71 outputs an L-level signal from the PT terminal (PT_A3) corresponding to the cutoff circuit 50A3. As a result, the output of gate circuit 772 becomes L-level, and gate circuit 76A3 outputs a disconnect signal to the cutoff circuit 50A3.

[0131] Next, the microcomputer 71 determines again whether both voltages Va and Vb have decreased (step S118). If voltages Va and Vb have decreased, the microcomputer 71 executes the processing after step S111. If the determination in step S118 is negative, the microcomputer 71 determines again whether either voltage Va or Vb has decreased (step S119). If either voltage Va or Vb has decreased, the process moves to the A3 / B3 output processing described later (step S121).

[0132] If the determination in steps S115 and S119 is negative, i.e., the voltages Va and Vb are above the threshold, the microcomputer 71 outputs a high-level control signal from the PT terminal (PT_C) corresponding to the cut-off circuit 50C (step S120). If the voltage Va is less than the overvoltage threshold, the A1hb' signal becomes low-level, so all inputs to the gate circuit 777 become high-level. Therefore, the output of the gate circuit 777 becomes high-level. Furthermore, since the voltages Va and Vb are above the ground detection threshold, the Cb signal becomes low-level. Therefore, all inputs to the gate circuit 76C become high-level, and the gate circuit 76C outputs a turn-on signal to the cut-off circuit 50C.

[0133] Next, the microcomputer 71 executes the A3 / B3 output processing (step S121). After the A3 / B3 output processing, the microcomputer 71 executes the latch clearing processing (step S122), ending a series of post-cutoff processing steps 1. In step S123, the microcomputer 71 outputs an H-level signal from the PT terminal (PT_LC) for latch clearing. As a result, an H-level signal is input to the R terminal of each latch 74, and the data held in the latch 74 is cleared (reset).

[0134] Figure 12 This indicates A3 / B3 output processing. The microcomputer 71 first reads the data from each INT terminal (step S130). Next, the microcomputer 71 determines whether the read data is 1 (H level), i.e., whether there is an anomaly detection (step S131). If there is no 1, the microcomputer 71 terminates the series of processes. If there is a 1, the microcomputer 71 outputs an L-level control signal from the PT terminal corresponding to the object's disconnect circuit 50 (step S132). For example, when the A1b signal is 1, the microcomputer 71 outputs an L-level signal from the PT terminal (PT_A1) corresponding to the disconnect circuit 50A1.

[0135] Next, the microcomputer 71 determines whether at least one of the A1b signal and the A1hb signal is 1 (step S133). That is, it determines whether at least one of the A1b signal and the A1hb signal is at level H. If the determination is yes in step S133, in order to suppress power consumption on the trunk 41A side, the microcomputer 71 outputs a control signal at level L from the PT terminal (PT_A3) corresponding to the disconnect circuit 50A3 (step S134). As a result, the output of gate circuit 772 becomes level L, and gate circuit 76A3 outputs a disconnect signal to disconnect circuit 50A3. Thus, the microcomputer 71 controls the disconnection of power supply to the low-priority load 11A. After executing step S134, the process proceeds to step S135.

[0136] If the determination in step S133 is negative, the microcomputer 71 determines whether at least one of the A1b, A1hb, Cb, and A1hb' signals is 1 (step S135). That is, it determines whether at least one of the A1b, A1hb, Cb, and A1hb' signals is at level H. If the determination in step S135 is negative, the microcomputer 71 terminates the A3 / B3 output processing.

[0137] If the determination in step S135 is yes, in order to suppress power consumption on the trunk line 41B side, the microcomputer 71 outputs an L-level control signal from the PT terminal (PT_B3) corresponding to the disconnection circuit 50B3 (step S136). As a result, the output of gate circuit 774 becomes L-level, and gate circuit 76B3 outputs a disconnect signal to the disconnection circuit 50B3. Thus, the microcomputer 71 controls the disconnection of power supply to the low-priority load 11B. After executing step S136, the microcomputer 71 ends the A3 / B3 output processing.

[0138] By performing the A3 / B3 output processing in this way, even if latch clearing is performed in step S123, the cut-off state (disconnected) of the cut-off circuit 50A3 and the cut-off circuit 50B3 can be maintained.

[0139] Figure 13 The INT_A1 interrupt handling is illustrated. If the INT terminal (INT_A1) used by the cutoff circuit 50A1 is input with an H-level A1b signal, the microcomputer 71 executes the INT_A1 interrupt handling. Additionally, when the value of the current Ia1 exceeds the threshold, the output of comparator 73A1 becomes H-level, and the A1b signal output from latch 74A1 also becomes H-level.

[0140] like Figure 13 As shown, firstly, the microcomputer 71 outputs an L-level signal as a control signal from the PT terminal (PT_A1) corresponding to the cutoff circuit 50A1 (step S140). Therefore, the output of gate circuit 771 becomes L-level, so even if the A1b signal, which is the main cause of this interruption, changes from H to L after latch-clearing, gate circuit 76A1 can maintain an L-level disconnect signal (a signal of L-level) for the cutoff circuit 50A1 to become cut off. Next, the microcomputer 71 determines whether the voltage Va and / or voltage Vb is below a threshold, i.e., whether it has decreased (step S141). If it has decreased, the microcomputer 71 outputs an L-level control signal from the PT terminal (PT_C) corresponding to the cutoff circuit 50C and waits for a specified time (step S142). With the L-level control signal, the output of gate circuit 777 becomes L-level, and gate circuit 76C outputs a disconnect signal to the cutoff circuit 50C. After waiting in standby mode, the microcomputer 71 executes... Figure 11 The cut-off post-processing 1 (step S143) shown ends a series of INT_A1 interrupt processes after execution.

[0141] If the determination in step S141 is negative, i.e., if voltages Va and Vb do not decrease, the microcomputer 71 executes... Figure 12 The A3 / B3 output processing is shown in step S144. Next, the microcomputer 71 performs latch clear processing (step S145), ending a series of INT_A1 interrupt processes. For example, in the event of a ground fault at terminal 30A1, the disconnect signal of the disconnect circuit 50A3 is output through the processing in step S144. Therefore, even if latch clear is performed, the disconnected state of the disconnect circuit 50A3 can be maintained.

[0142] Although the illustrations are omitted, the interrupt handling for INT_A2, INT_A3, INT_B1, INT_B2, and INT_B3 is the same as that for INT_A1 interrupt handling described above. For example, in the case of INT_A2 interrupt handling, in step S140, an L-level signal is output from the PT terminal (PT_A2) corresponding to the cutoff circuit 50A2 as a control signal. As described above, the microcomputer 71 first cuts off the cutoff circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 corresponding to each terminal 30. Even if they are cut off, if at least one of the voltages Va and Vb is lower than a threshold, the cutoff circuit 50C is controlled to be cut off.

[0143] Figure 14 The interrupt handling for INT_A1h' is illustrated. If the INT terminal (INT_A1h') receives an H-level A1hb' signal, the microcomputer 71 executes the INT_A1h' interrupt handling. Additionally, if the voltage Va exceeds the overvoltage threshold, the output of comparator 73AH2 becomes H-level, and the A1hb' signal output from latch 74AH2 also becomes H-level.

[0144] like Figure 14 As shown, firstly, the microcomputer 71 outputs an L-level signal as a control signal from the PT terminal (PT_C) corresponding to the cutoff circuit 50C (step S150). As a result, gate circuit 777 becomes L-level, so even if the A1hb' signal, which is the main cause of this interrupt, is subsequently latched and cleared, changing from H-level to L-level, gate circuit 76C can maintain the output of the disconnect signal (L-level signal) to the cutoff circuit 50C to achieve the cutoff state. Next, the microcomputer 71 executes the post-cutoff processing 2 (step S151) after outputting the cutoff indication (disconnect signal) to the cutoff circuit 50C. When post-cutoff processing 2 ends, the series of INT_A1H' interrupt processes are terminated.

[0145] Figure 15 This indicates post-cutoff processing 2. The microcomputer 71 first determines whether both voltages Va and Vb exceed a threshold, i.e., whether it is an overvoltage (step S160). The overvoltage determination threshold is pre-stored. The threshold is, for example, a value shared by voltages Va and Vb. If voltages Va and Vb are overvoltages, the microcomputer 71 determines whether the abnormal counter overflows (step S161). If overflow occurs, an overvoltage abnormal flag is set (step S162), and the process proceeds to the A3 / B3 output processing described later (step S170). If no overflow occurs, the abnormal counter is incremented, i.e., the value is increased by 1 (step S163), and after a specified standby time (step S164), the processing after step S160 is executed again.

[0146] If the determination in step S160 is negative, the microcomputer 71 determines whether the voltage Va on the side of the power supply 10A with high power supply capacity is an overvoltage (step S165). If the voltage Va is an overvoltage, in order to disconnect the disconnection circuit 50A1 closest to the power supply 10A, the microcomputer 71 outputs an L-level control signal from the corresponding PT terminal (PT_A1) and waits for a specified time (step S166). With the L-level control signal, the output of gate circuit 771 becomes L-level, and gate circuit 76A1 outputs a disconnect signal to disconnection circuit 50A1.

[0147] Next, the microcomputer 71 determines again whether voltages Va and Vb are overvoltages (step S167). If voltages Va and Vb are overvoltages, the microcomputer 71 executes the processing after step S161. If the determination in step S167 is negative, the microcomputer 71 determines again whether voltage Va is an overvoltage (step S168). If voltage Va is an overvoltage, the process moves to A3 / B3 output processing (step S170).

[0148] If the determination in steps S165 and S168 is negative, i.e., the voltage Va is not an overvoltage, the microcomputer 71 outputs a high-level control signal from the PT terminal (PT_C) (step S169). If the voltage Va is less than the overvoltage threshold, the A1hb' signal becomes low-level, therefore the inputs of gate circuit 777 all become high-level. Furthermore, if the voltages Va and Vb are above the grounding determination threshold, the Cb signal becomes low-level, therefore the inputs of gate circuit 76C all become high-level. Therefore, gate circuit 76C outputs a turn-on signal to the cut-off circuit 50C.

[0149] Next, the microcomputer 71 performs A3 / B3 output processing (step S170). After A3 / B3 output processing, the microcomputer 71 performs latch clearing processing (step S171), ending a series of post-cutoff processing 2.

[0150] Figure 16 The INT_A1h interrupt handling is illustrated. If the INT terminal (INT_A1h) is input with an H-level A1hb signal, the microcomputer 71 executes the INT_A1h interrupt handling. Furthermore, when the voltage Va exceeds the overvoltage threshold, the output of comparator 73AH1 becomes H-level, and the A1hb signal output from latch 74AH1 also becomes H-level.

[0151] like Figure 16 As shown, firstly, the microcomputer 71 outputs an L-level signal from the PT terminal (PT_A1) as a control signal (step S180). As a result, the output of gate circuit 771 becomes L-level, so even if the A1b signal, which is the main cause of this interruption, changes from H-level to L-level after latch clearing, gate circuit 76A1 can maintain an output of a disconnect signal (L-level signal) to the cut-off circuit 50A1 to achieve the cut-off state. Next, the microcomputer 71 determines whether voltage Va and / or voltage Vb is an overvoltage (step S181). In the case of an overvoltage, the microcomputer 71 outputs an L-level control signal from the PT terminal (PT_C) and waits for a specified time (step S182). With the L-level output, the output of gate circuit 777 becomes L-level, and gate circuit 76C outputs a disconnect signal to the cut-off circuit 50C. After waiting in standby mode, the microcomputer 71 executes... Figure 15 The cut-off post-processing 2 (step S183) shown ends a series of INT_A1h interrupt processes after execution.

[0152] If the determination in step S181 is negative, i.e., voltages Va and Vb are not overvoltages, then the microcomputer 71 executes... Figure 12 The A3 / B3 output processing is shown in step S184. Next, the microcomputer 71 performs latch clearing processing (step S185), ending a series of INT_A1h interrupt processing.

[0153] <Example of actions during abnormal situations> Figure 17 and Figure 18 This illustrates an example of operation when a ground fault occurs at terminal 30A3 (terminal A3). For example... Figure 17 As shown, when a ground fault occurs at terminal 30A3, current flows into the grounded area as indicated by the solid arrow, and the voltages of main lines 41A and 41B decrease, thus causing the voltages Va and Vb, which are their voltage dividers, to decrease. When the current Ia3 of the cut-off circuit 50A3 closest to the ground fault exceeds the threshold and the voltage Va is lower than the ground fault threshold, the A3b signal becomes H level, and gate circuit 76A3 outputs a disconnect signal to the cut-off circuit 50A3. When at least one of the voltages Va and Vb is lower than the threshold, the Cb signal becomes H level, and gate circuit 76C outputs a disconnect signal to the cut-off circuit 50C. When the Cb signal becomes H level, the B3b' signal becomes H level, and gate circuit 76B3 outputs a disconnect signal to the cut-off circuit 50B3.

[0154] As described above, in this embodiment, the threshold values ​​of comparators 73VA1 and 73VB1 are higher than the threshold values ​​of comparators 73VA2 and 73VB2. Therefore, a disconnect signal is first output to the disconnect circuit 50A3. Even if a disconnect signal is output to the disconnect circuit 50A3, the voltage does not recover. When at least one of the voltages Va and Vb is lower than the threshold value of the corresponding comparator 73VA2 or 73VB2, a disconnect signal is output to the disconnect circuit 50C. In addition, a disconnect signal is output to the disconnect circuit 50B3. When the voltages Va and Vb recover to above the threshold value after the disconnect circuit 50C is disconnected, an on signal is output to the disconnect circuit 50C through the interrupt processing of the microcomputer 71 described above. Figure 18 The diagram shows the disconnected state of circuits 50A3, 50B3, and 50C. The remaining disconnected circuits 50A1, 50A2, 50B1, and 50B2 are in the connected (energized) state.

[0155] First, by outputting a disconnect signal to the disconnect circuit 50A3, the disconnection of the disconnect circuit 50C on the main line 41 can be avoided when voltages Va and Vb are restored through this process. Even if the disconnect circuit 50C is disconnected, power can still be supplied to the high-priority load 11C from the paths of power supply 10A, main line 41A, and disconnect circuit 50A2, and power supply 10B, main line 41B, and disconnect circuit 50B2. Power supply can be maintained.

[0156] Figure 19 This illustrates an example of operation when terminal 30A3 cannot be disconnected due to a ground fault. Specifically, it shows an example of operation when the disconnection circuit 50A3 cannot be disconnected due to a fault such as a stuck connection. As described above, firstly, gate circuit 76A3 outputs a disconnect signal to the disconnection circuit 50A3. However, due to a stuck connection, the disconnection circuit 50A3 does not disconnect. In this case, voltages Va and Vb do not recover, and at least one of voltages Va and Vb is below the threshold of the corresponding comparators 73VA2 and 73VB2. Therefore, gate circuit 76C outputs a disconnect signal to the disconnection circuit 50C. Additionally, gate circuit 76B3 outputs a disconnect signal to the disconnection circuit 50B3. Figure 19 This indicates that circuit 50A3 is faulty (fixed connection), and circuits 50B3 and 50C are open. The remaining circuits 50A1, 50A2, 50B1, and 50B2 are in the closed state.

[0157] By disconnecting the disconnect circuit 50C, the main line 41B can be disconnected from the grounded main line 41A. Therefore, the voltage on the main line 41B is restored. Even if the disconnect circuit 50A3 closest to the grounding point fails (is stuck), power can still be supplied to the high-priority load 11C via the path of power supply 10B, main line 41B, and disconnect circuit 50B2. Power can be supplied to one of the redundancy features of load 11C to maintain its function. Furthermore, by disconnecting the disconnect circuit 50B3, power from power supply 10B can be preferentially supplied to load 11C. Thus, the function of the high-priority load 11C can also be maintained.

[0158] In the event of a ground fault at terminal 30B3 (terminal B3), the operation is the same as in the event of a ground fault at terminal 30A3. For example, in this embodiment, the disconnect circuit 50A3 corresponding to the low-priority load 11A is not disconnected. For instance, when disconnect circuit 50B3 is fixed in place, disconnect circuit 50C is disconnected, thereby restoring voltage to the main line 41A. Since power supply 10A has a higher power supply capacity than power supply 10B, disconnect circuit 50A3 may not be disconnected. For example, in a configuration where the power supply capacities of power supplies 10A and 10B are approximately equal, disconnect circuit 50A3 and disconnect circuit 50C may be disconnected together.

[0159] In the event of a ground fault at terminal 30A2 (terminal A2), the operation is the same as in the event of a ground fault at terminal 30A3. Power can be supplied to the high-priority load 11C via the path of power supply 10B, main line 41B, and disconnect circuit 50B2. Even if disconnect circuit 50A2 is closed, voltage can be restored to main line 41B by disconnecting disconnect circuit 50C. Power can be preferentially supplied to load 11C by disconnecting disconnect circuit 50B3. In the event of a ground fault at terminal 30B2 (terminal B2), the operation is the same as in the event of a ground fault at terminal 30B3. Power can be supplied to the high-priority load 11C via the path of power supply 10A, main line 41A, and disconnect circuit 50A2.

[0160] Figure 20 and Figure 21 This illustrates an example of operation when a ground fault occurs at terminal 30A1 (terminal A1). For example... Figure 20 As indicated by the solid arrow, current flows into the grounding point, causing a drop in the voltage of main lines 41A and 41B, thus reducing the voltage division values ​​Va and Vb. When the current Ia1 of the cutoff circuit 50A1 closest to the grounding point exceeds the threshold, the A1b signal becomes high level, and gate circuit 76A1 outputs a disconnect signal to cutoff circuit 50A1. If the A1b signal becomes high level, then the A3b' signal becomes high level, and gate circuit 76A3 outputs a disconnect signal to cutoff circuit 50A3. When at least one of the voltages Va and Vb is below the threshold, the Cb signal becomes high level, and gate circuit 76C outputs a disconnect signal to cutoff circuit 50C. Additionally, when the A1b signal and / or the Cb signal become high level, the B3b' signal becomes high level, and gate circuit 76B3 outputs a disconnect signal to cutoff circuit 50B3.

[0161] In this embodiment, a disconnect signal is first output to the disconnect circuit 50A1. Additionally, a disconnect signal is output to the disconnect circuit 50A3. Even if a disconnect signal is output to the disconnect circuit 50A1, the voltage does not recover. When at least one of the voltages Va and Vb is lower than the threshold values ​​of comparators 73VA2 and 73VB2, a disconnect signal is output to the disconnect circuit 50C. Additionally, a disconnect signal is output to the disconnect circuit 50B3. When the voltages Va and Vb become above the threshold values ​​after the disconnection of the disconnect circuit 50C, an on signal is output to the disconnect circuit 50C through the interruption processing of the microcomputer 71 described above. Figure 21 This indicates that circuits 50A1, 50A3, 50B3, and 50C are in the open state. The remaining circuits 50A2, 50B1, and 50B2 are in the closed state.

[0162] When voltages Va and Vb recover by outputting a disconnect signal to disconnect circuit 50A1, disconnection of disconnect circuit 50C, and consequently disconnection of disconnect circuit 50B3, can be avoided. Even if disconnect circuit 50C is disconnected, power can still be supplied to the load 11C, which has a higher power supply priority, via the path of power supply 10B, main line 41B, and disconnect circuit 50B2. By disconnecting disconnect circuit 50B3, power can be supplied to load 11C preferentially. By disconnecting disconnect circuit 50A3, even if disconnect circuit 50C is connected, power can still be supplied to load 11C preferentially. Even if disconnecting disconnect circuit 50A1 disconnects power supply 10A and ECU 20, power supply to load 11C can be maintained.

[0163] Figure 22 This illustrates an example of operation when terminal 30A1 cannot be disconnected due to a ground fault. Specifically, it shows an example of operation when the disconnection circuit 50A1 cannot be disconnected due to a fault such as a stuck connection. Even if gate circuit 76A1 outputs a disconnect signal to the disconnection circuit 50A1, the disconnection circuit 50A1 will not disconnect due to the stuck connection. In this case, voltages Va and Vb do not recover, and at least one of voltages Va and Vb is below the threshold values ​​of comparators 73VA2 and 73VB2. Therefore, gate circuit 76C outputs a disconnect signal to the disconnection circuit 50C. Additionally, gate circuit 76B3 outputs a disconnect signal to the disconnection circuit 50B3. Figure 22 This indicates that circuit 50A1 is faulty (fixed connection), and circuits 50A3, 50B3, and 50C are open. The remaining circuits 50A1, 50A2, 50B1, and 50B2 are in the closed state.

[0164] By disconnecting the disconnecting circuit 50C, the main line 41B can be disconnected from the grounded main line 41A. Therefore, the voltage on the main line 41B is restored. Thus, even if the disconnecting circuit 50A1, which is closest to the grounded point, fails (remains connected), power can still be supplied to the load 11C, which has a higher power supply priority, through the path of power source 10B, main line 41B, and disconnecting circuit 50B2. Furthermore, by disconnecting the disconnecting circuit 50B3, power from power source 10B can be preferentially supplied to the load 11C.

[0165] In the event of an overvoltage abnormality at terminal 30A1, the operation is identical to that in the event of a ground fault at terminal 30A1. When an overvoltage abnormality occurs at terminal 30A1, the voltage Va exceeds the overvoltage threshold, and the A1hb signal becomes H level. Consequently, gate circuit 76A1 outputs a disconnect signal to the disconnect circuit 50A1, and gate circuit 76A3 outputs a disconnect signal to the disconnect circuit 50A3. If the A1hb signal becomes H level, gate circuit 76C outputs a disconnect signal to the disconnect circuit 50C. Additionally, gate circuit 76B3 outputs a disconnect signal to the disconnect circuit 50B3.

[0166] Figure 23 and Figure 24 This illustrates an example of operation when an open-circuit fault occurs in terminal 30A1. Due to the open circuit, the power supply from power source 10A to ECU 20 is cut off. Therefore, the current supplied from power source 10B flows to each load 11. When the current Ia1 in the cut-off circuit 50A1 closest to the open circuit exceeds the threshold for both grounding and open circuit operation, the A1b signal becomes H level, and gate circuit 76A1 outputs a disconnect signal to cut-off circuit 50A1. Additionally, gate circuit 76A3 outputs a disconnect signal to cut-off circuit 50A3, and gate circuit 76B3 outputs a disconnect signal to cut-off circuit 50B3. Figure 24 The diagram shows the open state of disconnecting circuits 50A1, 50A3, and 50B3. The remaining disconnecting circuits 50A2, 50B1, 50B2, and 50C are in the closed state.

[0167] Even if the power supply from power source 10A is cut off due to an open circuit, power from power source 10B can be preferentially supplied to load 11C by disconnecting disconnection circuit 50A3. Similarly, by disconnecting disconnection circuit 50B3, power from power source 10B can be preferentially supplied to load 11C.

[0168] Figure 25 and Figure 26 An example of operation is shown when a ground fault occurs due to a disconnection delay. An example of operation is shown when a ground fault occurs due to a disconnection delay of the switch in disconnecting circuit 50. Figure 25 and Figure 26 In, with Figure 17 Similarly, an example of grounding occurring at terminal 30A3 is shown. Figure 27 This indicates the action of the control unit when a ground fault occurs.

[0169] The disconnect circuit 50 has a power-on reset circuit (not shown). When a ground fault occurs at terminal 30A3 and the resistance near the ground fault is low, the voltage division values ​​Va and Vb of the main lines 41A and 41B drop sharply. Therefore, a ground fault is detected by the current Ia3 and the voltages Va and Vb, and the S terminal of latches 74A3 and 74C is set to H. However, when the disconnect circuits 50A3 and 50C fail to disconnect (cut off) due to a delay and the main lines 41A and 41B are momentarily disconnected (grounded), the disconnect circuit 50 performs a power-on reset.

[0170] As described above, the ECU20 of this embodiment includes a capacitor 63. Therefore, even if a momentary interruption occurs, the voltage of the control unit 70 is maintained. That is, the data in the latch 74 is retained. Therefore, upon recovery from a power-on reset (restart), as... Figure 27 As shown, the H-level signal output from latch 74A3 is used as signal A3b and outputs a disconnect signal to disconnect circuit 50A3. Additionally, the H-level signal output from latch 74C is used as signal Cb and outputs a disconnect signal to disconnect circuit 50C. Since signal B3b' becomes H-level based on signal Cb, it outputs a disconnect signal to disconnect circuit 50B3. Connect signals are output to other disconnect circuits 50A1, 50A2, 50B1, and 50B2. Therefore, the transient interruption (grounding) of trunk lines 41A and 41B can be suppressed. That is, repeated transient interruptions can be suppressed.

[0171] <Summary of the First Implementation> According to this embodiment, in addition to the disconnection circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 (terminal disconnection circuits) corresponding to the terminals 30, the ECU20 also includes a disconnection circuit 50C (mains disconnection circuit) on the main line 41. When at least one of the current flowing through the disconnection circuit 50 and the voltage of the power supply line 40 meets a predetermined abnormality detection condition, the control unit 70 outputs a disconnection signal to the corresponding terminal disconnection circuit and the main line disconnection circuit among the plurality of terminal disconnection circuits that exceed the current threshold. Therefore, even if the terminal disconnection circuit closest to the abnormality location cannot be disconnected when a ground fault occurs, the disconnection of the main line disconnection circuit can prevent the inability to supply power to all loads 11. That is, it is possible to maintain the power supply to at least a portion of the loads 11.

[0172] As illustrated in this embodiment, the load 11 may also include a load 11C (first load) with high power supply priority and loads 11A and 11B (second loads) with low power supply priority. Terminals 30A2 and 30B2, electrically connected to the main line 41A and the main line 41B respectively, can be connected to the common load 11C. Therefore, even if the disconnection circuit 50C is disconnected, the power supply to the high-priority load 11C can be maintained. Furthermore, the control unit 70 may also control at least one of the disconnection circuits 50A3 and 50B3 corresponding to the loads 11A and 11B to a disconnected state, while controlling the disconnection circuit 50C to a disconnected state or controlling the disconnection circuit 50A1 to a disconnected state. This ensures that the power supplied to the high-priority load 11C is maintained.

[0173] The control unit 70 may also output a disconnect signal to the disconnect circuit 50C if the value of the current flowing through the disconnect circuit 50C exceeds a predetermined threshold current. As illustrated in this embodiment, the control unit 70 may also output a disconnect signal to the disconnect circuit 50C if at least one of the voltage division values ​​Va and Vb of the main lines 41A and 41B is lower than a predetermined threshold voltage. Since the voltage of the disconnect circuits 50 is monitored only, and not the voltage of the main lines 41A and 41B, the configuration can be simplified.

[0174] The control unit 70 can also output a disconnect signal to the corresponding disconnect circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 when any one of the currents Ia1, Ia2, Ia3, Ib1, Ib2, and Ib3 exceeds a predetermined threshold current. As illustrated in this embodiment, the control unit 70 can also output a disconnect signal to the corresponding disconnect circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 when at least one of the voltages Va and Vb is below a predetermined threshold voltage and any one of the currents Ia1, Ia2, Ia3, Ib1, Ib2, and Ib3 exceeds a predetermined threshold current. Since voltages Va and Vb are also used, the current threshold for detecting grounding can be set lower. This improves the disconnect response and suppresses false disconnections.

[0175] Alternatively, the threshold voltage for cutting off the cutoff circuit 50C and the threshold voltages for cutting off the cutoff circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 can be set to a common value. As illustrated in this embodiment, the threshold voltage for cutting off the cutoff circuit 50C can also be lower than the threshold voltages for cutting off the cutoff circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3. That is, the thresholds of comparators 73VA2 and 73VB2 are lower than the thresholds of comparators 73VA1 and 73VB1. Therefore, the cutoff circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 corresponding to the abnormality are first disconnected, and even if the voltages Va and Vb decrease, the cutoff circuit 50C is disconnected. Thus, unnecessary disconnection of the cutoff circuit 50C can be suppressed.

[0176] As illustrated in this embodiment, the control unit 70 can also reconnect the disconnect circuit 50C after it has been disconnected, when voltages Va and Vb reach or exceed the threshold voltages. After grounding detection and redundancy operation, if the disconnected disconnect circuit 50 is fault-free, the disconnect circuit 50C is reconnected. This allows for continued operation of the redundant power supply for the load 11.

[0177] As illustrated in this embodiment, the ECU 20 may also include a capacitor 63 connected to the power path from the power supply 10 to the control unit 70, and the control unit 70 may have a latching function to retain anomaly detection data. The anomaly detection data is data related to the fulfillment of anomaly detection conditions. As described above, when the corresponding disconnection circuit 50 fails to disconnect in time due to a delay in detecting a ground fault, and the main lines 41A and 41B are momentarily disconnected, each disconnection circuit 50 is powered on and reset. By including the capacitor 63, the operating voltage of the control unit 70 can be ensured even if a momentary interruption occurs. That is, the control unit 70 can retain anomaly detection data based on ground fault detection. Therefore, during recovery (restart), the anomaly detection data can be used to disconnect the corresponding disconnection circuit 50.

[0178] As illustrated in this embodiment, the power supply capacity of power supply 10A (first power supply) can be higher than that of power supply 10B (second power supply). In this configuration where power supply 10A has a higher power supply capacity, if the direction of current from the cut-off circuit 50A1 to terminal 30A1 is set to positive, the control unit 70 can control the cut-off circuit 50A1 to be in a cut-off state when the current flowing through it is positive or zero. Therefore, not only grounding can be detected, but also open circuits can be detected.

[0179] In a configuration where the power supply capacity of power source 10A is high, control unit 70 can also output a disconnect signal to disconnect circuit 50A1 and disconnect circuit 50C when the voltage Va exceeds the overvoltage threshold. Therefore, even if disconnect circuit 50A1 fails when the supply voltage from power source 10A is an overvoltage, the disconnection of disconnect circuit 50C can suppress the impact of the overvoltage on the main line 41B side.

[0180] Alternatively, the overvoltage threshold voltages for cutting off the cutoff circuit 50C and the overvoltage threshold voltages for cutting off the cutoff circuit 50A1 can be set to a common value. As illustrated in this embodiment, the overvoltage threshold voltage used for cutting off the cutoff circuit 50C can also be higher than the threshold voltage used for cutting off the cutoff circuit 50A1. The threshold voltage of comparator 73AH2 is higher than the threshold voltage of comparator 73AH1. Therefore, the cutoff circuit 50A1 is disconnected first, and the cutoff circuit 50C is also disconnected even if the voltage Va rises. Thus, unnecessary disconnection of the cutoff circuit 50C can be suppressed.

[0181] The ECU20 of this embodiment has gate circuits 772-776 for cutting off the power supply to low-priority loads 11A and 11B. Additionally, it has a latch 74 (SR latch) for holding an anomaly sensing signal. Through hardware processing, the cutoff response to anomaly sensing can be improved.

[0182] <Variation Example> like Figure 28 As shown, ECU20 can also be configured to not detect an open-circuit fault at terminal 30A1. ECU20 includes gate circuit 75A1. The output signals of comparators 73A1 and 73VA1 are input to gate circuit 75A1. The output signal of gate circuit 75A1 is input to terminal S of latch 74A1. When current Ia1 is greater than the threshold voltage for ground detection and voltage Va is lower than the threshold voltage for ground detection, gate circuit 75A1 outputs a signal at level H. Figure 29 As shown, the threshold for grounding detection, compared with the current Ia1, is dedicated to this purpose and is not shared with open-circuit detection. When a ground fault occurs at terminal 30A1, the current Ia1 flows in the opposite direction to its normal operation, i.e., the positive direction. Therefore, a positive (+) value is set. By setting it to a low value close to zero, the cutoff circuit 50A1 can be quickly disconnected via hardware processing upon grounding.

[0183] The number and configuration of load 11 are not limited to the examples above. For example... Figure 30 As shown, terminals 30A2 and 30B2 can also be configured to connect to different loads 11. Figure 30 In the diagram, load 11D (load D) is electrically connected to terminal 30A2, and load 11E (load E) is electrically connected to terminal 30B2. For example... Figure 30 As shown, it can also be configured to supply power only to loads 11 that do not have redundancy. Alternatively, it can be configured so that no priority is set for power supply among the multiple loads 11.

[0184] Alternatively, multiple high-priority loads 11 can be provided with power supply. Alternatively, multiple high-priority loads 11 can be connected to the ECU 20 at approximately the same location. Alternatively, multiple low-priority loads 11 can be provided for each trunk line 41A, 41B. Alternatively, multiple loads 11 corresponding to each trunk line 41A, 41B can be connected to the ECU 20 at approximately the same location. The loads 11 can also have power distribution functions. Power can also be distributed from the loads 11 to downstream devices.

[0185] ECU20 Figure 1 As shown, it features a communication IC66. Figure 6 As shown, the control unit 70 (microcomputer 71) can communicate via the communication IC 66. Therefore, instead of cutting off the power supply to the low-priority loads 11A and 11B, it is possible to send an action restriction request to the loads 11A and 11B to reduce power consumption. As a result, the power consumption of the loads 11A and 11B can be reduced, ensuring the power supply to the high-priority load 11C.

[0186] like Figure 1 and Figure 6 As shown, the control unit 70 (microcomputer 71) acquires the values ​​of the currents Ia1, Ia2, Ia3, Ib1, Ib2, Ib3, and Ic flowing in each cut-off circuit 50. Therefore, fault diagnosis of the current detection unit 57 of the cut-off circuits 50A1, 50A2, 50A3, and 50C can also be performed by comparing the currents Ia1, Ia2, and Ia3 on the power supply 10A side with the current Ic. Specifically, if the sum of the currents flowing through the terminal cut-off circuits on the power supply 10A side (-Ia1-Ia3-Ia2) is approximately the same as the current Ic, it is normal. Similarly, fault diagnosis of the current detection unit 57 of the cut-off circuits 50B1, 50B2, 50B3, and 50C can also be performed by comparing the currents Ib1, Ib2, and Ib3 on the power supply 10B side with the current Ic. Specifically, if the sum of the currents flowing through the terminal cutoff circuit on the power supply 10B side (Ib1+Ib3+Ib2) is approximately the same as the current Ic, then it is normal.

[0187] (Second Implementation) This embodiment is a variation based on a prior embodiment, and the description of the prior embodiment can be referenced. In the previous embodiment, the power supply to the low-priority loads 11A and 11B was cut off in the hardware configuration. Instead, the microcomputer 71 may also cut off the power supply to the low-priority loads 11A and 11B.

[0188] Figure 31 This describes the configuration of the control unit 70 in the ECU 20 of this embodiment. The control unit 70 is derived from the previous embodiment (see reference 1). Figure 6 The configuration shown excludes gate circuits 772, 773, 774, 775, and 776. The microcomputer 71 has the function of cutting off the power supply to low-priority loads 11A and 11B (low-priority cutoff function). The microcomputer 71 (processor) executes processing equivalent to gate circuits 772 and 773. When the microcomputer 71 receives an H-level signal as an A1b signal and / or an A1hb signal at the corresponding INT terminal, it outputs an L-level control signal from the PT_A3 terminal. Therefore, gate circuit 76A3 outputs a disconnect signal to the cutoff circuit 50A3.

[0189] The microcomputer 71 performs processing equivalent to gate circuits 774, 775, and 776. When the microcomputer 71 receives an H-level signal as at least one of the A1b, Cb, A1hb, and A1hb' signals at the corresponding INT terminal, it outputs an L-level control signal from the PT_B3 terminal. Consequently, gate circuit 76B3 outputs a disconnect signal for the cutoff circuit 50B3. Other configurations are the same as those of the ECU 20 described in the prior embodiment.

[0190] <Summary of the Second Implementation> The ECU20 in this embodiment can also achieve the same effect as the configuration described in the prior embodiment. The microcomputer 71 has the function of cutting off the power supply to low-priority loads 11A and 11B, thus simplifying the circuit configuration of the control unit 70.

[0191] (Third Implementation) This embodiment is a variation based on a prior embodiment, and the description of the prior embodiment can be referenced. In the previous embodiment, the fault detection data was latched by hardware. The control unit 70 is equipped with an SR latch. Alternatively, the fault detection data may be latched by a microcomputer 71.

[0192] Figure 32 This describes the configuration of the control unit 70 in the ECU 20 of this embodiment. The control unit 70 is derived from the previous embodiment (see reference 1). Figure 31 The configuration shown excludes all latches 74 and gate circuits 76A1, 76A2, 76A3, 76B1, 76B2, 76B3, 76C, 771, and 777. The microcomputer 71 has the function of holding abnormal detection data (latch function). The microcomputer 71 performs processing equivalent to that of latches 74A1, 74A2, 74A3, 74AH1, 74AH2, 74B1, 74B2, 74B3, and 74C. The INT terminal of the microcomputer 71 is input with the output signals of comparators 73A1, 73AH1, and 73AH2, and the output signals of gate circuits 75A2, 75A3, 75B1, 75B2, 75B3, and 75C. The control signal output from the PT terminal of the microcomputer 71 is input to the drive section of the corresponding cutoff circuit 50.

[0193] Even in the event of a momentary interruption, the operating voltage of the microcomputer 71 is maintained through capacitor 63. The microcomputer 71 retains the abnormality detection data acquired through the INT terminal. Upon recovery after power-on reset, it outputs a control signal corresponding to the retained abnormality detection data. Other configurations are the same as those of the ECU 20 described in the prior embodiment.

[0194] <Summary of the Third Implementation> The ECU 20 in this embodiment can achieve the same effect as the configuration described in the prior embodiment. In addition to the function of cutting off power to low-priority loads 11A and 11B, the microcomputer 71 also has the function of latching abnormality detection data. Therefore, the circuit configuration of the control unit 70 can be further simplified.

[0195] (Fourth Implementation) This embodiment is a variation based on a prior embodiment, and the description of the prior embodiment can be referenced. In the previous embodiment, the current flowing through each cutoff circuit 50 was used to detect grounding. Instead, grounding may also be detected solely by cutting off circuit 50C.

[0196] Figure 33 This describes the configuration of the control unit 70 in the ECU 20 of this embodiment. The control unit 70 includes a microcomputer 71, a DAC 72, multiple comparators 73, multiple latches 74, and multiple gate circuits. The DAC 72 sets the threshold values ​​of each comparator 73 according to the instructions of the microcomputer 71.

[0197] Comparator 73 does not include comparators corresponding to the cutoff circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3. Comparator 73 includes comparators 73VA and 73VB for detecting voltage drops. The threshold values ​​of comparators 73VA and 73VB are, for example, common values. To avoid grounding detection based on currents Ia1, Ia2, Ia3, Ib1, Ib2, and Ib3, one comparator 73VA and one comparator 73VB are included for each. When voltage Va is below the threshold, comparator 73VA outputs a signal at level H. When voltage Vb is below the threshold, comparator 73VB outputs a signal at level H. Comparator 73 also includes comparators 73AH1 and 73AH2 for overvoltage, similar to the prior embodiment.

[0198] Comparator 73 also includes comparators 73C1 and 73C2. The inverting input terminal of comparator 73C1 is input with a threshold value, and the non-inverting input terminal is input with a current Ic. The inverting input terminal of comparator 73C2 is input with a current Ic, and the non-inverting input terminal is input with a threshold value. Comparator 73C1 detects anomalies in the positive direction, i.e., from trunk 41A towards trunk 41B. Comparator 73C1, for example, detects a ground fault on the trunk 41B side. Comparator 73C2 detects anomalies in the negative direction, i.e., from trunk 41B towards trunk 41A. Comparator 73C2, for example, detects a ground fault on the trunk 41A side.

[0199] Figure 34 The threshold values ​​are shown. The threshold value of comparator 73C1 is a positive (+) value and is set between the normal operating current range and the overcurrent threshold on the positive side to detect grounding on the trunk 41B side. The threshold value of comparator 73C2 is a negative (-) value and is set between the normal operating current range and the overcurrent threshold on the negative side to detect grounding on the trunk 41A side.

[0200] Latch 74 does not include latches corresponding to cut-off circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3. Latch 74 includes latches 74AH1 and 74AH2, similar to the prior embodiment. Latch 74 also includes latches 74C1 and 74C2. The S-terminal of latch 74C1 is input to the output signal of gate circuit 778. Gate circuit 778 is an AND gate, and it is input to the output signals of comparators 73C1 and 73VB. Latch 74C1 outputs the signal Cb1. The S-terminal of latch 74C2 is input to the output signal of gate circuit 779. Gate circuit 779 is an AND gate, and it is input to the output signals of comparators 73C2 and 73VA. Latch 74C2 outputs the signal Cb2.

[0201] The microcomputer 71 has four INT terminals. As signals indicating interrupt requests, the A1hb signal, A1hb' signal, Cb1 signal, and Cb2 signal are input to the microcomputer 71.

[0202] The gate circuits include gate circuits 76C, 777~789. Gate circuits 76C, 777~789 are all AND gates with a NOT gate connected to one of their input terminals.

[0203] The control signal output from the PT terminal (PT_C) of the microcomputer 71 is input to gate circuit 777 in the same manner as in the prior embodiment. Gate circuit 777 is input with the control signal and the A1hb' signal. The output signal of gate circuit 777 is input to gate circuit 780. Gate circuit 780 is input with the output signal of gate circuit 777 and the inverted Cb2 signal. The output signal of gate circuit 780 is input to gate circuit 76C. Gate circuit 76C is input with the output signal of gate circuit 780 and the inverted Cb1 signal. That is, when at least one of the following conditions is met—the control signal is at level L, the A1hb' signal is at level H, the Cb2 signal is at level H, and the Cb1 signal is at level H—gate circuit 76C outputs a disconnect signal to the disconnect circuit 50C.

[0204] The control signal output from the PT terminal (PT_A1) of the microcomputer 71 is input to gate circuit 781. Gate circuit 781 receives the control signal and the inverted Cb2 signal. The output signal of gate circuit 781 is input to gate circuit 782. Gate circuit 782 receives the output signal of gate circuit 781 and the inverted A1hb signal. That is, if at least one of the following conditions is met: the control signal is at level L, the A1hb signal is at level H, and the Cb2 signal is at level H, gate circuit 782 outputs a disconnect signal to the disconnect circuit 50A1.

[0205] The control signal output from the PT terminal (PT_A2) of the microcomputer 71 is input to the gate circuit 783. The gate circuit 783 is input with the control signal and the inverted Cb2 signal. When the control signal is at level L and / or the Cb2 signal is at level H, the gate circuit 783 outputs a disconnect signal to the disconnect circuit 50A2.

[0206] The control signal output from the PT terminal (PT_A3) of the microcomputer 71 is input to gate circuit 784. Gate circuit 784 receives the control signal and the inverted Cb2 signal. The output signal of gate circuit 784 is input to gate circuit 785. Gate circuit 785 receives the output signal of gate circuit 784 and the inverted A1hb signal. When at least one of the following conditions is met—the control signal is at level L, the A1hb signal is at level H, and the Cb2 signal is at level H—gate circuit 785 outputs a disconnect signal to the disconnect circuit 50A3.

[0207] The control signal output from the PT terminal (PT_B1) of the microcomputer 71 is input to the gate circuit 786. The gate circuit 786 is input with the control signal and the inverted Cb1 signal. When the control signal is at level L and / or the Cb1 signal is at level H, the gate circuit 786 outputs a disconnect signal to the disconnect circuit 50B1.

[0208] The control signal output from the PT terminal (PT_B2) of the microcomputer 71 is input to the gate circuit 787. The gate circuit 787 is input with the control signal and the inverted signal of the Cb1 signal. When the control signal is at level L and / or the Cb1 signal is at level H, the gate circuit 787 outputs a disconnect signal to the disconnect circuit 50B2.

[0209] The control signal output from the PT terminal (PT_B3) of the microcomputer 71 is input to gate circuit 788. Gate circuit 788 is input with the control signal and a signal obtained by inverting the Cb1 signal. The output signal of gate circuit 788 is input to gate circuit 789. Gate circuit 789 is input with the output signal of gate circuit 788 and a signal obtained by inverting the Cb2 signal. When at least one of the following conditions is met—the control signal is at level L, the Cb1 signal is at level H, and the Cb2 signal is at level H—gate circuit 789 outputs a disconnect signal to the disconnect circuit 50A3. For example, when the Cb2 signal is at level H, gate circuit 789 outputs a disconnect signal, thus enabling the power supply to the low-priority load 11B to be cut off in the event of a ground fault on the main line 41A side. Other configurations are the same as those of the ECU 20 described in the prior embodiment.

[0210] <Summary of the Fourth Implementation> The ECU 20 in this embodiment can achieve the same effect as the configuration described in the prior embodiment. In this embodiment, the control unit 70 outputs a disconnect signal to the disconnect circuit 50C when at least one of the voltages Va and Vb is below a predetermined threshold voltage and the current Ic exceeds a predetermined threshold current. Since grounding detection can be performed solely through the disconnect circuit 50C, the circuit configuration can be simplified.

[0211] <Variation Example> like Figure 35 As shown, the microcomputer 71 can also have the function of cutting off the power supply to low-priority loads. Figure 35 The control unit 70 shown becomes from Figure 33 The configuration shown excludes gate circuits 785 and 789. Microcomputer 71 has the function of cutting off low-priority loads 11A and 11B. Microcomputer 71 (processor) executes processing equivalent to gate circuit 785. If microcomputer 71 receives an input H-level signal as the A1hb signal, it outputs an L-level control signal from the PT_A3 terminal. Gate circuit 784 outputs a disconnect signal to the cutoff circuit 50A3. Microcomputer 71 executes processing equivalent to gate circuit 789. If microcomputer 71 receives an input H-level signal as the Cb2 signal, it outputs an L-level control signal from the PT_B3 terminal. Gate circuit 788 outputs a disconnect signal to the cutoff circuit 50B3.

[0212] like Figure 36 As shown, the microcomputer 71 can also have the function of latching abnormal detection data. Figure 36 The control unit 70 shown becomes from Figure 35 The configuration shown excludes all latches 74 and gate circuits 76C, 777, and 780-787. The microcomputer 71 has the function of holding abnormality detection data. The microcomputer 71 performs processing equivalent to that of latches 74AH1, 74AH2, 74C1, and 74C2. The INT terminal of the microcomputer 71 is input with the output signals of comparators 73AH1 and 73AH2 and the output signals of gate circuits 778 and 789. The control signal output from the PT terminal of the microcomputer 71 is input to the drive section of the corresponding cutoff circuit 50.

[0213] Even in the event of a momentary interruption, the operating voltage of the microcomputer 71 is maintained through capacitor 63. The microcomputer 71 retains the abnormality detection data prior to the momentary interruption. Upon power-on reset and recovery, the microcomputer 71 outputs a control signal corresponding to the retained abnormality detection data.

[0214] (Fifth implementation method) This embodiment is a variation based on a prior embodiment, and the description of the prior embodiment can be referenced. In the prior embodiment, power is supplied from multiple power sources 10 to a single ECU 20. Alternatively, power can be supplied from multiple power sources 10 to multiple ECU 20 connected in a ring.

[0215] <Power System> Figure 37 An example of a power supply system is shown. The power supply system includes multiple power supplies 10 and multiple ECUs 20. As an example, the power supply 10 in this embodiment is the same as in the prior embodiment, including power supply 10A and power supply 10B.

[0216] Similar to the prior embodiment, ECU 20 receives power from multiple power sources 10 and distributes power to multiple loads 11. As an example, the ECU 20 in this embodiment includes six ECUs 20A, 20B, 20C, 20D, 20E, and 20F. The number and function of the connected loads 11 can also vary depending on the ECU 20. Similar to the prior embodiment, the loads 11 connected to each ECU 20 can also include loads with higher power supply priority and loads with lower priority. Alternatively, only a portion of the ECUs 20 may include both high-priority and low-priority loads as connected loads 11. For convenience, in... Figure 37 In this embodiment, the configuration of each ECU 20 is set to be common, and the number of loads 11 connected to each ECU 20 is set to 3. The configuration of the terminals 30, power wiring 40, and disconnection circuit 50 in the ECU 20 is the same as that shown in the previous embodiment (for example, refer to...). Figure 1 (Same as above.) ECU20 has capacitor 63.

[0217] Multiple ECUs 20 are connected in a ring via power cable 13. Figure 37 In the example shown, ECUs 20A, 20B, 20C, 20D, 20E, and 20F are arranged in the order of ECU 20A, ECU 20B, and ECU 20F. In a ring configuration, for example, ECUs 20B and 20F are positioned next to ECU 20A. ECU 20C is positioned next to ECUs 20B and 20D. A power supply 10A is connected to power line 13 connecting ECUs 20A and ECU 20F. A power supply 10B is connected to power line 13 connecting ECUs 20C and ECU 20D.

[0218] For example, power is supplied from power source 10A to ECU 20A via power line 13; power is supplied from power source 10B to ECU 20A via power line 13 and ECUs 20B and 20C; power is supplied from power source 10A to ECU 20F via power line 13; power is supplied from power source 10B to ECU 20F via power line 13 and ECUs 20D and 20E; power is supplied from power source 10A to ECU 20B via power line 13 and ECU 20A; and power is supplied from power source 10B to ECU 20B via power line 13 and ECU 20C.

[0219] Multiple ECUs 20 can communicate with each other via the communication bus 12. As an example, in this embodiment, adjacent ECUs 20 share a portion of the information obtained from the INT terminal. Similar to previous embodiments, the load 11 can communicate with other devices, other loads 11, and ECUs 20 other than the connected objects via the communication bus 12.

[0220] <Control Department> Figure 38 This describes the configuration of the control unit 70 in the ECU20 of this embodiment. Figure 39 The threshold is shown. The control unit 70 includes a microcomputer 71, a DAC 72, multiple comparators 73, multiple latches 74, and multiple gate circuits.

[0221] Comparator 73 is configured according to the prior embodiment (see reference). Figure 6 The configuration excludes comparators 73AH1, 73AH2, 73VA1, 73VA2, 73VB1, and 73VB2, and adds comparators 73VA and 73VB. Comparator 73 includes comparators 73A1, 73A2, 73A3, 73B1, 73B2, 73B3, 73VA, and 73VB. The threshold values ​​of comparators 73VA and 73VB are, for example, common values.

[0222] Figure 39 This represents an example of a set threshold. In Figure 39 In, with Figure 8 Similarly, the threshold for grounding detection, the overcurrent threshold, and the normal operating current range are shown. The positive and negative directions are the same as in the prior embodiment. Through the loop connection, the currents Ia1 and Ib1 can flow in both positive and negative directions under normal conditions. The grounding detection threshold for currents Ia1 and Ib1 is a positive (+) value and is set between the normal operating current range and the overcurrent threshold. The grounding detection threshold for currents Ia1 and Ib1 is approximately equal to the grounding detection threshold on the B side of current Ic.

[0223] The latch 74 is configured according to the prior embodiment (see reference). Figure 6 The configuration of latches 74AH1, 74AH2, and 74C is excluded. Latch 74 includes latches 74A1, 74A2, 74A3, 74B1, 74B2, and 74B3.

[0224] Gate circuits are constructed from the prior embodiments shown (see reference). Figure 6 The configuration excludes gate circuits 75C, 76A1, 76B1, and 771-777, and adds gate circuits 790, 791, and 792. Gate circuits 790, 791, and 792 are all OR gates. Gate circuit 790 outputs a Cb signal. The Cb signal is input to the INT terminal of gate circuit 76C and microcomputer 71. Gate circuit 790 is input with the output signals of gate circuits 791 and 792. Gate circuit 791 is input with the A2b signal output from latch 74A2 and the A3b signal output from latch 74A3. Gate circuit 792 is input with the B2b signal output from latch 74B2 and the B3b signal output from latch 74B3. Other configurations are the same as those of the ECU20 described in the prior embodiment.

[0225] <Disconnection Conditions> Figure 40 The cutting conditions of the cutting circuit 50 based on the microcomputer 71 are shown. The microcomputer 71 of the control unit 70, according to... Figure 40 The cutoff logic shown cuts off (disconnects) the corresponding cutoff circuit 50. Based on ground detection (latch) information from the INT terminal and ground detection (latch) information obtained via communication from the adjacent ECU 20, the microcomputer 71 outputs L-level control signals to the cutoff circuits 50A1, 50B1, and 50C configured on the main line 41 and cuts them off. Cutoff circuits 50A2, 50A3, 50B2, and 50B3 are cut off by the ground detection (latch) circuits in hardware. As described above, each signal 1 corresponds to an H-level signal.

[0226] The cut-off circuit 50A1 receives a control signal output from the PT terminal (PT_A1) of the microcomputer. When the A1b signal input from the INT terminal is 1, and at least one of the B1b, B2b, and B3b signals obtained from the adjacent ECU 20 is 1, the microcomputer 71 outputs an L-level signal as a control signal. That is, in this ECU 20, when the voltage Va decreases and the current Ia1 exceeds a threshold, and / or in the adjacent ECU 20, when the voltage Vb decreases and at least one of the currents Ib1, Ib2, and Ib3 exceeds a threshold, the microcomputer 71 outputs a disconnect signal to the cut-off circuit 50A1.

[0227] The cutoff circuit 50A2 receives the output signal from the gate circuit 76A2. The gate circuit 76A2 receives the control signal output from the PT terminal (PT_A2) of the microcomputer 71 and the inverted signal of the A2b signal. When the control signal is at level L and / or the A2b signal output from the latch 74A2 is at level H, the gate circuit 76A2 outputs a disconnect signal to the cutoff circuit 50A2.

[0228] The cutoff circuit 50A3 receives the output signal from the gate circuit 76A3. The gate circuit 76A3 receives the control signal output from the PT terminal (PT_A3) of the microcomputer 71 and the signal after the A3b signal is inverted. When the control signal is at level L and / or the A3b signal output from the latch 74A3 is at level H, the gate circuit 76A3 outputs a disconnect signal to the cutoff circuit 50A3.

[0229] The disconnect circuit 50B1 receives a control signal output from the PT terminal (PT_B1) of the microcomputer. When the B1b signal input from the INT terminal is 1, and at least one of the A1b, A2b, and A3b signals obtained from the adjacent ECU 20 on the right is 1, the microcomputer 71 outputs an L-level signal as a control signal. That is, in this ECU 20, when the voltage Vb decreases and the current Ib1 exceeds a threshold, and / or in the adjacent ECU 20 on the right, when the voltage Va decreases and at least one of the currents Ia1, Ia2, and Ia3 exceeds a threshold, the microcomputer 71 outputs a disconnect signal to the disconnect circuit 50B1.

[0230] The cutoff circuit 50B2 receives the output signal from the gate circuit 76B2. The gate circuit 76B2 receives the control signal output from the PT terminal (PT_B2) of the microcomputer 71 and the inverted B2b signal. When the control signal is at level L and / or the B2b signal output from the latch 74B2 is at level H, the gate circuit 76B2 outputs a disconnect signal to the cutoff circuit 50B2.

[0231] The cutoff circuit 50B3 receives the output signal from the gate circuit 76B3. The gate circuit 76B3 receives the control signal output from the PT terminal (PT_B3) of the microcomputer 71 and the inverted B3b signal. When the control signal is at level L and / or the B3b signal output from the latch 74B3 is at level H, the gate circuit 76B3 outputs a disconnect signal to the cutoff circuit 50B3.

[0232] The cut-off circuit 50C receives the output signal from the gate circuit 76C. The gate circuit 76C receives the control signal output from the PT terminal (PT_C) of the microcomputer 71 and the Cb signal output from the gate circuit 790. When at least one of the following conditions is met: the A2b signal, A3b signal, B2b signal, and B3b signal input from the INT terminal is 1; the B1b signal obtained from the left adjacent ECU 20 is 1; and the A1b signal obtained from the right adjacent ECU 20 is 1, the microcomputer 71 outputs an L-level signal as the control signal. When the control signal is L-level and / or the Cb signal output from the gate circuit 790 is H-level, the gate circuit 76C outputs a disconnect signal to the cut-off circuit 50C.

[0233] <Example of operation during grounding> Figure 41 This illustrates an example of operation when a ground fault occurs in the power line 13 connecting ECU20B and ECU20C. Specifically, it shows an example of operation when a ground fault occurs between terminal 30B1 of ECU20B and terminal 30A1 of ECU20C.

[0234] As indicated by the solid arrows, current flows from power supplies 10A and 10B into the grounding portion. Because the voltage division value Vb corresponding to the voltage of the grounding-side trunk line 41B in ECU 20B decreases and the current Ib1 flowing in the cutoff circuit 50B1 closest to the grounding portion exceeds a threshold, the B1b signal becomes H level. Additionally, in ECU 20C, the voltage division value Va corresponding to the voltage of the grounding-side trunk line 41A decreases, and the current Ia1 flowing in the cutoff circuit 50A1 closest to the grounding portion exceeds a threshold, so the A1b signal becomes 1 (H level). Since the B1b signal of ECU 20B is 1, and the A1b signal of the adjacent ECU 20C on the right, obtained through communication, is 1, the microcomputer 71 of ECU 20B outputs an L level control signal to the cutoff circuit 50B1. Since the A1b signal of the adjacent ECU 20C on the right is 1, the microcomputer 71 of ECU 20B outputs an L level control signal to the cutoff circuit 50C.

[0235] Similarly, since the A1b signal of ECU20C is 1 and the B1b signal of the neighboring ECU20B obtained through communication is 1, the microcomputer 71 of ECU20C outputs an L-level control signal to the cut-off circuit 50A1. Since the B1b signal of the neighboring ECU20B is 1, the microcomputer 71 of ECU20C outputs an L-level control signal to the cut-off circuit 50C.

[0236] Based on the above, such as Figure 41 As shown, the disconnection circuits 50B1 and 50C of ECU20B and 50A1 and 50C of ECU20C are disconnected. Therefore, power can be supplied from power source 10A to loads 11A and 11C of ECU20B. Power can also be supplied from power source 10B to loads 11A and 11C of ECU20B via paths ECU20D, 20E, and 20F. Additionally, power can be supplied from power source 10B to loads 11B and 11C of ECU20B. Power can also be supplied from power source 10A to loads 11B and 11C of ECU20B via paths ECU20F, 20E, and 20D. Even when disconnection circuit 50C is disconnected, power supply to the higher-priority load 11C can be maintained. Furthermore, by disconnecting the cut-off circuits 50C of both ECUs 20B and 20C, even if a short circuit fault or other failure occurs in the cut-off circuit 50A1 of ECU 20C that prevents disconnection, the power supply to the high-priority load 11C can still be maintained.

[0237] Figure 42 This illustrates an example of operation when a ground fault occurs at terminal 30B3 of ECU20B. Specifically, it shows an example of operation when a ground fault occurs in the power line connecting terminal 30B3 of ECU20B and load 11B.

[0238] As indicated by the solid arrows, current flows from power supplies 10A and 10B into the grounding portion. Because the voltage division value Vb corresponding to the voltage of the main line 41B on the ground side in ECU 20B decreases, and the current Ib3 flowing through the cutoff circuit 50B3 closest to the grounding portion exceeds the threshold, the B3b signal becomes 1. Furthermore, through gate circuits 76B3 and 792, 790, and 76C, control signals at level L are output to the cutoff circuits 50B3 and 50C. Therefore, power can be supplied from power supply 10A to the loads 11A and 11C of ECU 20B. Power can also be supplied from power supply 10B to the loads 11A and 11C of ECU 20B via paths ECU 20D, 20E, and 20F. Even when the cutoff circuit 50C is disconnected, the power supply to the high-priority load 11C can be maintained.

[0239] Furthermore, since the B3b signal of the neighboring ECU 20B obtained through communication is 1, the microcomputer 71 of ECU 20C outputs a control signal of level L to the cutoff circuit 50A1. Therefore, power can be supplied from power supply 10B to each load 11 (11A, 11B, 11C) of ECU 20B. Power can be supplied from power supply 10A to each load 11 of ECU 20C via paths ECU 20F, 20E, and 20D. Moreover, by disconnecting the cutoff circuit 50C of ECU 20B, even if a short circuit or other failure occurs in the cutoff circuit 50B3 of ECU 20B or the cutoff circuit 50A1 of ECU 20C, the power supply to the high-priority load 11C of ECU 20B can be maintained.

[0240] As shown in the prior embodiment, the disconnection circuits 50A1, 50A2, 50A3, 50B1, 50B2, and 50B3 corresponding to terminal 30 may be disconnected first, and then the disconnection circuit 50C may be disconnected. Alternatively, the disconnection circuit 50C may be restored to operation when the voltage exceeds a threshold value after the disconnection circuit 50C is disconnected.

[0241] <Summary of the Fifth Implementation> The ECU20 in this embodiment can also achieve the same effect as the configuration described in the prior embodiment.

[0242] (Other implementation methods) The disclosure in this specification and accompanying drawings is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and modifications made by those skilled in the art based on them. For example, the disclosure is not limited to combinations of components and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure may have additional portions that can be added to the embodiments. The disclosure includes content that omits components and / or elements of the embodiments. The disclosure includes substitutions or combinations of components and / or elements between one embodiment and other embodiments. The scope of the disclosure is not limited to the description of the embodiments. Several technical scopes of the disclosure are indicated by the description in the claims and should be understood to include all modifications within the meaning and scope equivalent to the description in the claims.

[0243] The disclosures in the specification and drawings are not limited by the claims. The disclosures in the specification and drawings encompass the technical ideas described in the claims, and involve a wider range of technical ideas than those described in the claims. Therefore, without being bound by the claims, various technical ideas can be extracted from the disclosures in the specification and drawings.

[0244] When referring to an element or layer as "above," "connected," "joined," or "combined," it sometimes means that it is directly above, connected, or combined with other elements or layers, and sometimes there is an intervening element or intervening layer. Conversely, when referring to an element as "directly above," "directly connected," "directly joined," or "directly combined" with other elements or layers, there is no intervening element or intervening layer. Other terms used to describe relationships between elements should be interpreted in the same way (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). As used in this specification, the term "and / or" includes any and all combinations relating to one or more of the related listed items. That is, the description of A and / or B refers to at least one of A and B.

[0245] The spatially relative terms "inside," "outside," "back," "down," "low," "up," and "high" are used here to facilitate the description of the relationship of one element or feature relative to other elements or features, as illustrated in the figures. In addition to the orientations depicted in the figures, the spatially relative terms can also be intended to encompass different orientations of the device in use or operation. For example, if the device in the figure is flipped, the element described as "down" or "directly below" other elements or features faces "up" of other elements or features. Therefore, the term "down" can encompass both up and down orientations. The device may also face other directions (or rotate 90 degrees or other orientations), and the spatially relative descriptors used in this specification are interpreted accordingly.

[0246] As a processor, an example of a CPU found in the microcomputer 71 is shown, but it is not limited to this. MPU, GPU, DFP, etc., can be used. MPU is an abbreviation for Micro-Processing Unit. GPU is an abbreviation for Graphics Processing Unit. DFP is an abbreviation for Data Flow Processor. Alternatively, SoC can be used instead of the microcomputer 71. SoC is an abbreviation for System on Chip. ASIC, FPGA, etc., can also be used. ASIC is an abbreviation for Application Specific Integrated Circuit. FPGA is an abbreviation for Field-Programmable Gate Array.

[0247] Control programs can also be stored as computer-executable instructions on a non-transitory tangible storage medium. Medium for storing control programs can include HDDs, SSDs, and flash memory. HDD stands for Hard-disk Drive. SSD stands for Solid State Drive.

[0248] (The disclosure of technical ideas) This specification discloses several technical ideas described in the following list of items. Some items are sometimes described by selectively referencing a preceding item in a multiple dependent form in a subsequent item. Furthermore, some items may be described by referring to another multiple dependent form. Items described in these multiple dependent forms define several technical ideas.

[0249] <Technical Idea 1> An electronic control device receives power from multiple power sources (10) and distributes power to multiple loads, wherein the electronic control device comprises: Terminal (30) includes a plurality of power terminals (30A1, 30B1) electrically connected to a plurality of said power sources and a plurality of load terminals (30A2, 30A3, 30B2, 30B3) electrically connected to a plurality of said loads. The power wiring (40) includes a main line (41) that electrically connects a first power terminal, which is one of the plurality of power terminals, to a second power terminal, which is another of the power terminals, and a plurality of branch lines (42) that electrically connect the main line to the load terminal. Multiple disconnection circuits (50) are respectively provided on the main line and the branch line, and energize or disconnect the current supplied from the power source; and The control unit (70) controls the plurality of said disconnect circuits. The disconnection circuit includes a trunk disconnection circuit (50C) disposed on the trunk line and a plurality of terminal disconnection circuits (50A1, 50A2, 50A3, 50B1, 50B2, 50B3) disposed corresponding to the terminals. The terminal disconnect circuit includes: a plurality of load disconnect circuits, each corresponding to a load terminal and disposed on the branch line; a first power disconnect circuit, disposed on the trunk line (41A) between the trunk line disconnect circuit and the first power terminal, between the connection portion of the branch line and the first power terminal; and a second power disconnect circuit, disposed on the trunk line (41B) between the trunk line disconnect circuit and the second power terminal, between the connection portion of the branch line and the second power terminal. When at least one of the current flowing through the disconnect circuit and the voltage of the power supply line meets a specified abnormality detection condition, the control unit controls a portion of the plurality of terminal disconnect circuits and the main line disconnect circuit to a disconnect state.

[0250] <Technological Ideas 2> The electronic control device according to technical concept 1 The load includes a first load and a second load whose power supply priority is lower than that of the first load. One of the load terminals electrically connected to the first trunk line and one of the load terminals electrically connected to the second trunk line are connected to the first load.

[0251] <Technological Idea 3> The electronic control device according to technical concept 2 The control unit controls at least one of the load disconnection circuits corresponding to the second load to a disconnection state while controlling the trunk disconnection circuit to a disconnection state or the first power disconnection circuit to a disconnection state.

[0252] <Technological Ideas 4> The electronic control device according to technical concept 2 The control unit sends an action restriction request to reduce power consumption to at least one of the second loads while controlling the trunk disconnect circuit to a disconnected state or the first power disconnect circuit to a disconnected state.

[0253] <Technological Idea 5> The electronic control device according to any one of technical concepts 1-4, If at least one of the voltages of the first trunk line and the second trunk line is lower than a predetermined threshold voltage, the control unit controls the trunk line disconnection circuit to be in a disconnected state.

[0254] <Technological Ideas 6> The electronic control device according to any one of technical concepts 1-4, If at least one of the voltages of the first trunk line and the second trunk line is lower than a predetermined threshold voltage and the current flowing through the trunk line disconnection circuit is higher than a predetermined threshold current, the control unit controls the trunk line disconnection circuit to be in a disconnected state.

[0255] <Technological Ideas 7> The electronic control device according to technical concept 5 If at least one of the voltages of the first trunk line and the second trunk line is lower than a predetermined threshold voltage and the current flowing through the terminal disconnect circuit is higher than a predetermined threshold current, the control unit controls the corresponding terminal disconnect circuit to be in a disconnected state.

[0256] <Technological Ideas 8> The electronic control device according to technical concept 7 The threshold voltage used to cut off the trunk disconnect circuit is lower than the threshold voltage used to cut off the terminal disconnect circuit.

[0257] <Technological Ideas 9> The electronic control device according to any one of technical concepts 5-8, After the control unit controls the trunk line disconnection circuit to the disconnected state, when the voltage of the first trunk line and the voltage of the second trunk line reach a threshold voltage or above, the control unit controls the trunk line disconnection circuit to the energized state.

[0258] <Technological Ideas 10> The electronic control device according to any one of technical concepts 1-9, It also includes a capacitor (63) connected to the power path from the power source to the control unit. The control unit has a latching function to maintain data related to meeting the anomaly detection conditions.

[0259] <Technological Ideas 11> The electronic control device according to any one of technical concepts 1-9, The power supply capacity of the first power source electrically connected to the first power terminal is higher than that of the second power source electrically connected to the second power terminal.

[0260] <Technological Ideas 12> The electronic control device according to technical concept 11 If the direction of current from the first power cut-off circuit to the first power terminal is defined as the positive direction... If the current flowing through the first power cut-off circuit is positive or zero, the control unit controls the first power cut-off circuit to be in a cut-off state.

[0261] <Technological Ideas 13> The electronic control device according to technical concept 11 or technical concept 12 If the voltage of the first trunk line exceeds the overvoltage threshold, the control unit controls the first power cut-off circuit and the trunk line cut-off circuit to be in a cut-off state.

[0262] <Technological Ideas 14> The electronic control device according to technical concept 13 The overvoltage threshold used to disconnect the trunk disconnect circuit is higher than the overvoltage threshold used to disconnect the first power disconnect circuit.

[0263] <Technological Ideas 15> The electronic control device according to any one of technical concepts 1-14, The control unit performs fault diagnosis of the cutting-off circuit based on the current flowing through the trunk cutting-off circuit and the current flowing through the terminal cutting-off circuit.< / ecu>

Claims

1. An electronic control device that receives power from multiple power sources (10) and distributes power to multiple loads, characterized in that, The electronic control device includes: Terminal (30) includes a plurality of power terminals (30A1, 30B1) electrically connected to a plurality of said power sources and a plurality of load terminals (30A2, 30A3, 30B2, 30B3) electrically connected to a plurality of said loads. The power wiring (40) includes a main line (41) that electrically connects a first power terminal, which is one of the plurality of power terminals, to a second power terminal, which is another of the power terminals, and a plurality of branch lines (42) that electrically connect the main line to the load terminal. Multiple disconnection circuits (50) are respectively provided on the main line and the branch line, and energize or disconnect the current supplied from the power source; and The control unit (70) controls the plurality of said disconnect circuits. The disconnection circuit includes a trunk disconnection circuit (50C) disposed on the trunk line and a plurality of terminal disconnection circuits (50A1, 50A2, 50A3, 50B1, 50B2, 50B3) disposed corresponding to the terminals. The terminal disconnect circuit includes: a plurality of load disconnect circuits, each corresponding to a load terminal and disposed on the branch line; a first power disconnect circuit, disposed on the trunk line (41A) between the trunk line disconnect circuit and the first power terminal, between the connection portion of the branch line and the first power terminal; and a second power disconnect circuit, disposed on the trunk line (41B) between the trunk line disconnect circuit and the second power terminal, between the connection portion of the branch line and the second power terminal. When at least one of the current flowing through the disconnect circuit and the voltage of the power supply line meets a specified abnormality detection condition, the control unit controls a portion of the plurality of terminal disconnect circuits and the main line disconnect circuit to a disconnect state.

2. The electronic control device according to claim 1, characterized in that, The load includes a first load and a second load whose power supply priority is lower than that of the first load. One of the load terminals electrically connected to the first trunk line and one of the load terminals electrically connected to the second trunk line are connected to the first load.

3. The electronic control device according to claim 2, characterized in that, The control unit controls at least one of the load disconnection circuits corresponding to the second load to a disconnection state while controlling the trunk disconnection circuit to a disconnection state or the first power disconnection circuit to a disconnection state.

4. The electronic control device according to claim 2, characterized in that, The control unit sends an action restriction request to reduce power consumption to at least one of the second loads while controlling the trunk disconnect circuit to a disconnected state or the first power disconnect circuit to a disconnected state.

5. The electronic control device according to claim 1, characterized in that, If at least one of the voltages of the first trunk line and the second trunk line is lower than a predetermined threshold voltage, the control unit controls the trunk line disconnection circuit to be in a disconnected state.

6. The electronic control device according to claim 1, characterized in that, If at least one of the voltages of the first trunk line and the second trunk line is lower than a predetermined threshold voltage and the current flowing through the trunk line disconnection circuit is higher than a predetermined threshold current, the control unit controls the trunk line disconnection circuit to be in a disconnected state.

7. The electronic control device according to claim 5, characterized in that, If at least one of the voltages of the first trunk line and the second trunk line is lower than a predetermined threshold voltage and the current flowing through the terminal disconnect circuit is higher than a predetermined threshold current, the control unit controls the corresponding terminal disconnect circuit to be in a disconnected state.

8. The electronic control device according to claim 7, characterized in that, The threshold voltage used to cut off the trunk disconnect circuit is lower than the threshold voltage used to cut off the terminal disconnect circuit.

9. The electronic control device according to any one of claims 5-8, characterized in that, After the control unit controls the trunk line disconnection circuit to the disconnected state, when the voltage of the first trunk line and the voltage of the second trunk line reach a threshold voltage or above, the control unit controls the trunk line disconnection circuit to the energized state.

10. The electronic control device according to any one of claims 1-8, characterized in that, It also includes a capacitor (63) connected to the power path from the power source to the control unit. The control unit has a latching function to maintain data related to meeting the anomaly detection conditions.

11. The electronic control device according to any one of claims 1-8, characterized in that, The power supply capacity of the first power source electrically connected to the first power terminal is higher than that of the second power source electrically connected to the second power terminal.

12. The electronic control device according to claim 11, characterized in that, If the direction of current from the first power cut-off circuit to the first power terminal is defined as the positive direction... If the current flowing through the first power cut-off circuit is positive or zero, the control unit controls the first power cut-off circuit to be in a cut-off state.

13. The electronic control device according to claim 11, characterized in that, If the voltage of the first trunk line exceeds the overvoltage threshold, the control unit controls the first power cut-off circuit and the trunk line cut-off circuit to be in a cut-off state.

14. The electronic control device according to claim 13, characterized in that, The overvoltage threshold used to disconnect the trunk disconnect circuit is higher than the overvoltage threshold used to disconnect the first power disconnect circuit.

15. The electronic control device according to any one of claims 1-8, characterized in that, The control unit performs fault diagnosis of the cutting-off circuit based on the current flowing through the trunk cutting-off circuit and the current flowing through the terminal cutting-off circuit.

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