Detection circuit, method, airbag controller, in-vehicle device, and vehicle

Abstract

The application relates to the technical field of circuit processing, and discloses a detection circuit, a method, an airbag controller, a vehicle-mounted device and a vehicle. An interface selection module of the detection circuit of the application comprises m interface units, a driving module comprises n driving units, and a to-be-detected switch comprises i switch units; when 1<=m The application relates to the technical field of circuit processing, and discloses a detection circuit, a method, an airbag controller, a vehicle-mounted device and a vehicle. An interface selection module of the detection circuit of the application comprises m interface units, a driving module comprises n driving units, and a to-be-detected switch comprises i switch units; when 1<=m The application relates to the technical field of circuit processing, and discloses a detection circuit, a method, an airbag controller, a vehicle-mounted device and a vehicle. An interface selection module of the detection circuit of the application comprises m interface units, a driving module comprises n driving units, and a to-be-detected switch comprises i switch units; when 1<=m

Description

Technical Field

[0001] This application relates to the field of circuit processing technology, and in particular to a detection circuit, method, airbag controller, vehicle-mounted equipment, and vehicle. Background Technology

[0002] In the design of the vehicle's electronic airbag control unit (ACU), the ACU can perform full diagnostics on all switches requiring complete diagnostics (e.g., occupant airbag disable switches, driver's seatbelt buckle circuit switches, and rollover airbag disable switches), and control the airbag status based on the switch states. For example, the ACU can perform full diagnostics on occupant airbag disable switches and determine whether to deploy the airbag based on their state; it can perform full diagnostics on driver's seatbelt buckle circuit switches and determine the degree of airbag deployment based on their state; and it can perform full diagnostics on rollover airbag disable switches and determine whether to deploy the airbag based on their state.

[0003] Currently, the ACU (Automatic Control Unit) can perform full diagnostics on switches requiring full diagnostics using its switch detection circuit and low-side drive (LD) circuit with controllable switch timing. For every n switches in a vehicle requiring full diagnostics, the ACU's switch detection circuit needs n switch detection interfaces and the drive circuit needs n LDs. However, due to limitations in the size, functionality, and cost of the integrated chips (circuit / printed circuit board, PCB) used in the ACU, some ACUs cannot simultaneously accommodate n switch detection interfaces and n LDs. This prevents the detection of all switches requiring full diagnostics in the vehicle, hindering the prediction and prevention of potential problems before they occur, and increasing the risk of unexpected failures. Summary of the Invention

[0004] To address the issue that some ACUs cannot simultaneously set up n switch detection interfaces and n LDs due to limitations in the size, functionality, and cost of the integrated chips (circuits / PCBs) used by the ACU, embodiments of this application provide a detection circuit, method, airbag controller, vehicle-mounted equipment, and vehicle.

[0005] In a first aspect, embodiments of this application provide a detection circuit, including a detection module, an interface selection module, a driving module, and a switch to be detected. The detection module is connected to a first end of the interface selection module, a second end of the interface selection module is connected to a first end of the switch to be detected, and a second end of the switch to be detected is connected to a first end of the driving module. The interface selection module includes m interface units, the driving module includes n driving units, and the switch to be detected includes i switching units, where m < i and / or n < i. When 1 ≤ m < i, the second end of the first interface unit among the m interface units is connected to the first end of multiple switching units among the i switching units, and the second ends of the multiple switching units are connected to multiple different driving units. When 1 ≤ n < i, the first end of the first driving unit among the n driving units is connected to the second end of multiple switching units among the i switching units, and the first ends of the multiple switching units are connected to the second ends of multiple different interface units.

[0006] In this way, the interface unit in the interface selection module and / or the drive unit in the drive module can connect to multiple switch units in i switch units. That is, the interface unit in the interface selection module and / or the drive unit in the drive module can be reused in the detection process of the switch unit, thereby reducing the number of interface units and / or control units required in the detection circuit, that is, reducing the number of electronic devices in the detection circuit, and reducing the size, chip function, and circuit cost of the integrated chip (circuit / PCB) used by the ACU.

[0007] In one possible implementation, i ≤ m × n.

[0008] In one possible implementation, the first interface unit includes a first voltage interface unit and a first current interface unit. The first voltage interface unit is connected to the voltage detection terminal of the detection module, and the first current interface unit is connected to the current detection terminal of the detection module. The second terminals of both the first voltage interface unit and the first current interface unit are connected to the first terminal of the first switching unit among the i switching units. The second terminal of the first switching unit is connected to the first terminal of the first driving unit among the n driving units.

[0009] In one possible implementation, the first switching unit includes a first switch, a first resistor, and a second resistor; the first voltage interface unit includes a second switch; the first current interface unit includes a third switch; the first driving unit includes a fourth switch; the second terminals of both the second and third switches are connected to the first terminal of the first resistor; the second terminal of the first resistor is connected to the first terminal of the second resistor and the first terminal of the first switch; the second terminal of the second resistor and the second terminal of the first switch are both connected to the first terminal of the fourth switch; or the second terminal of the second switch and the second terminal of the third switch are both connected to the first resistor and the first terminal of the first switch; the second terminal of the first resistor and the second switch are connected to the first terminal of the second resistor; and the second terminal of the second resistor is connected to the first terminal of the fourth switch.

[0010] It is understood that the first switch can be the switch SWI1 in the embodiment of this application, the second switch can be the MUX1_V in the embodiment of this application, the third switch can be the MUX1_I in the embodiment of this application, the fourth switch can be the switch LD1 in the embodiment of this application, the first resistor can be the first resistor R1 in the embodiment of this application, and the second resistor can be the second resistor R2 in the embodiment of this application.

[0011] In one possible implementation, a control module is also included; the control module is used to control the second switch to be in the on state and to control the third and fourth switches to be in the off state; the detection module is used to detect that the first voltage corresponding to the first switch is greater than the voltage threshold and output a first signal, wherein the first signal indicates that there is a short circuit between at least one switching unit and the power supply in the switch to be detected.

[0012] In this embodiment, the voltage of the first switch is measured when the first voltage characterization detection module, interface selection module, and drive module do not form a closed loop with the switch to be detected.

[0013] In one possible implementation, the control module is used to control the second and third switches to be in the on state and control the fourth switch to be in the off state; the detection module is used to detect that the first current corresponding to the first switch is greater than the current threshold and output a second signal, wherein the second signal indicates that there is a short circuit between at least one switch unit and ground in the switch to be detected.

[0014] In this embodiment, the current of the first switch is measured when the first current characterization detection module, interface selection module, and drive module do not form a closed loop with the switch to be detected.

[0015] In one possible implementation, corresponding to a first voltage less than or equal to a voltage threshold and a first current less than or equal to a current threshold, the control module controls the second, third, and fourth switches to be in a conducting state; the detection module is used to detect the second voltage and the second current corresponding to the first switch; the detection module is used to output a third signal when the ratio of the second voltage and the second current is greater than the first threshold, the third signal indicating an open circuit between the second terminal of the interface selection module and the first terminal of the drive module; the detection module is used to output a fourth signal when the ratio of the second voltage and the second current is less than or equal to the first threshold and greater than the second threshold, the fourth signal indicating that the first switch is open; the detection module is used to output a fifth signal when the ratio of the second voltage and the second current is less than or equal to the second threshold and greater than the third threshold, the fifth signal indicating that the second voltage and the second current are invalid; the detection module is used to output a sixth signal when the ratio of the second voltage and the second current is less than or equal to the third threshold and greater than the fourth threshold, the sixth signal indicating that the first switch is closed; the detection module is used to output a seventh signal when the ratio of the second voltage and the second current is less than or equal to the fourth threshold, the seventh signal indicating a short circuit between the second terminal of the interface selection module and the first terminal of the drive module.

[0016] In this embodiment, the second voltage is the voltage of the first switch when the detection module, interface selection module, and drive module form a closed loop with the switch to be tested, and the second current is the current of the first switch when the detection module, interface selection module, and drive module form a closed loop with the switch to be tested.

[0017] In one possible implementation, the second switch is turned on earlier than the third switch, and the third switch is turned on earlier than the fourth switch.

[0018] In one possible implementation, the i switching units include at least one of an occupant airbag disable switch, a switch for the driver's seatbelt buckle circuit, and a rollover airbag disable switch.

[0019] Secondly, embodiments of this application provide a detection method, which is used in any detection circuit provided by the first aspect and various possible implementations of the first aspect; the method includes: a control module in the detection circuit is used to control a second switch in a voltage interface unit in a first interface unit connected to a first switch unit to be in a conducting state, a third switch in a current interface unit in a first interface unit connected to the first switch unit to be in a de-energized state, and a fourth switch in a first drive unit connected to the first switch unit to be in a de-energized state; the detection module is used to detect that a first voltage corresponding to the first switch in the first switch unit is greater than a voltage threshold, and output a first signal, wherein the first signal indicates that there is a short circuit between at least one switch unit and a power supply in the switch to be detected.

[0020] In this embodiment, the voltage of the first switch is measured when the first voltage characterization detection module, interface selection module, and drive module do not form a closed loop with the switch to be detected.

[0021] In one possible implementation, the control module is used to control the second and third switches to be in the on state and control the fourth switch to be in the off state; the detection module is used to detect that the first current corresponding to the first switch is greater than the current threshold and output a second signal, wherein the second signal indicates that there is a short circuit between at least one switch unit and ground in the switch to be detected.

[0022] In this embodiment, the current of the first switch is measured when the first current characterization detection module, interface selection module, and drive module do not form a closed loop with the switch to be detected.

[0023] In one possible implementation, when the first voltage is less than or equal to a voltage threshold and the first current is less than or equal to a current threshold, the control module controls the second, third, and fourth switches to be in a conducting state; the detection module is used to detect the second voltage and the second current corresponding to the first switch; when the ratio of the second voltage and the second current is greater than the first threshold, a third signal is output, indicating an open circuit between the second terminal of the interface selection module and the first terminal of the drive module; when the ratio of the second voltage and the second current is less than or equal to the first threshold but greater than the second threshold, a fourth signal is output, indicating that the first switch is open; when the ratio of the second voltage and the second current is less than or equal to the second threshold but greater than the third threshold, a fifth signal is output, indicating that the second voltage and the second current are invalid; when the ratio of the second voltage and the second current is less than or equal to the third threshold but greater than the fourth threshold, a sixth signal is output, indicating that the first switch is closed; when the ratio of the second voltage and the second current is less than or equal to the fourth threshold, a seventh signal is output, indicating a short circuit between the second terminal of the interface selection module and the first terminal of the drive module.

[0024] In this embodiment, the second voltage is the voltage of the first switch when the detection module, interface selection module, and drive module form a closed loop with the switch to be tested, and the second current is the current of the first switch when the detection module, interface selection module, and drive module form a closed loop with the switch to be tested.

[0025] In this embodiment, the interface unit in the interface selection module and / or the drive unit in the drive module can connect to multiple switch units in the i switch units. That is, the interface unit in the interface selection module and / or the drive unit in the drive module can be reused during the detection process of the switch unit, thereby reducing the number of interface units and / or control units required in the detection circuit, i.e. reducing the number of electronic devices in the detection circuit, and reducing the size, chip function, and circuit cost of the integrated chip (circuit / PCB) used by the ACU.

[0026] Thirdly, embodiments of this application provide an airbag controller, including the first aspect and any detection circuit provided by various possible implementations of the first aspect.

[0027] Fourthly, embodiments of this application provide an in-vehicle device including an airbag controller as provided in the third aspect and various possible implementations of the third aspect above.

[0028] Fifthly, embodiments of this application provide a vehicle including in-vehicle equipment as provided in the fourth aspect and various possible implementations of the fourth aspect above. Attached Figure Description

[0029] Figure 1 A schematic diagram of a detection circuit is shown.

[0030] Figure 2 A timing diagram of the switches in a detection circuit is shown;

[0031] Figure 3 According to an embodiment of this application, a schematic diagram of a detection circuit is shown;

[0032] Figure 4a According to an embodiment of this application, a schematic diagram of a detection circuit is shown when m=1, n=4, and i=4.

[0033] Figure 4b According to an embodiment of this application, a schematic diagram of the circuit structure of a detection circuit when m=1, n=4, i=4 is shown.

[0034] Figure 5a According to an embodiment of this application, a timing diagram of each switch in a detection circuit is shown when m=1, n=4, i=4;

[0035] Figure 5b According to an embodiment of this application, another timing diagram of each switch in the detection circuit is shown when m=1, n=4, i=4;

[0036] Figure 6a According to an embodiment of this application, a schematic diagram of a detection circuit is shown when m=4, n=1, and i=4.

[0037] Figure 6b According to an embodiment of this application, a schematic diagram of the circuit structure of a detection circuit when m=4, n=1, i=4 is shown.

[0038] Figure 7 According to an embodiment of this application, a timing diagram of each switch in a detection circuit is shown when m=4, n=1, i=4;

[0039] Figure 8a According to an embodiment of this application, a schematic diagram of a detection circuit is shown when m=2, n=2, and i=4.

[0040] Figure 8b According to an embodiment of this application, a schematic diagram of the circuit structure of a detection circuit when m=2, n=2, i=4 is shown;

[0041] Figure 9 According to an embodiment of this application, a timing diagram of each switch in a detection circuit is shown when m=2, n=2, i=4;

[0042] Figure 10 According to an embodiment of this application, a structural schematic diagram of an in-vehicle device 1300 is shown. Detailed Implementation

[0043] The illustrative embodiments of this application include, but are not limited to, a detection circuit, a method, an airbag controller, an in-vehicle device, and a vehicle.

[0044] Understandably, currently, when performing a full diagnostic on vehicle switches, each switch requires a switch detection interface in the ACU's switch detection circuit and an LD to work together to achieve the diagnosis. This full diagnostic includes detecting whether the switch is short-circuited to the power supply, short-circuited to ground, open-circuited, short-circuited, whether the switch's resistance is valid, and whether the switch is actually closed. The following section will combine... Figure 1 and Figure 2 This paper introduces the working principle of ACU for full diagnostics of switches.

[0045] like Figure 1 As shown, the ACU's PCB includes a switch detection circuit 100 and a low-side drive circuit 200. The switch detection circuit 100 includes a power supply 101 with current and voltage detection capabilities and a multiplexer (MUX) 102. The multiplexer 102 includes switches MUX1_I, MUX1_V, MUX2_I, MUX2_V, MUX3_I, MUX3_V, MUX4_I, and MUX4_V. The low-side drive circuit 200 includes switches LD1, LD2, LD3, and LD4. The ACU's PCB is connected to the vehicle's test switch 300, which includes switches SWI1, SWI2, SWI3, and SWI4, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8.

[0046] In this embodiment, switch SWI1 is connected in parallel with the second resistor R2, switch SWI2 is connected in parallel with the fourth resistor R4, switch SWI3 is connected in parallel with the sixth resistor R6, and switch SWI4 is connected in parallel with the eighth resistor R8. That is, the current detection port of power supply 101 is connected to the first terminal of switch MUX1_I, the first terminal of switch MUX2_I, the first terminal of switch MUX3_I, and the first terminal of switch MUX4_I; the voltage detection port of power supply 101 is connected to the first terminal of switch MUX1_V, the first terminal of switch MUX2_V, the first terminal of switch MUX3_V, and the first terminal of switch MUX4_V. The second terminals of switches MUX1_I and MUX1_V are connected to the first terminal of the first resistor R1; the second terminals of switches MUX2_I and MUX2_V are connected to the first terminal of the third resistor R3; the second terminals of switches MUX3_I and MUX3_V are connected to the first terminal of the fifth resistor R5; and the second terminals of switches MUX4_I and MUX4_V are connected to the first terminal of the seventh resistor R7.

[0047] The second terminal of the first resistor R1 is connected to the first terminal of the second resistor R2 and the first terminal of switch SWI1. The second terminal of the second resistor R2 and the second terminal of switch SWI1 are connected to the first terminal of switch LD1, and the second terminal of switch LD1 is grounded. The second terminal of the third resistor R3 is connected to the first terminal of the fourth resistor R4 and the first terminal of switch SWI2. The second terminal of the fourth resistor R4 and the second terminal of switch SWI2 are connected to the first terminal of switch LD2, and the second terminal of switch LD2 is grounded. The second terminal of the fifth resistor R5 is connected to the first terminal of the sixth resistor R6 and the first terminal of switch SWI3. The second terminal of the sixth resistor R6 and the second terminal of switch SWI3 are connected to the first terminal of switch LD3, and the second terminal of switch LD3 is grounded. The second terminal of the seventh resistor R7 is connected to the first terminal of the eighth resistor R8 and the first terminal of switch SWI4. The second terminal of the eighth resistor R8 and the second terminal of switch SWI4 are connected to the first terminal of switch LD4, and the second terminal of switch LD4 is grounded.

[0048] It is understood that in some other embodiments, switch SWI1 is connected in parallel with the first resistor R1, switch SWI2 is connected in parallel with the third resistor R3, switch SWI3 is connected in parallel with the fifth resistor R5, and switch SWI4 is connected in parallel with the seventh resistor R7. That is, the current detection port of power supply 101 is connected to the first terminal of switch MUX1_I, the first terminal of switch MUX2_I, the first terminal of switch MUX3_I, and the first terminal of switch MUX4_I; the voltage detection port of power supply 101 is connected to the first terminal of switch MUX1_V, the first terminal of switch MUX2_V, the first terminal of switch MUX3_V, and the first terminal of switch MUX4_V. The second terminals of switches MUX1_I and MUX1_V are connected to the first terminals of the first resistor R1 and the first terminal of switch SWI1; the second terminals of switches MUX2_I and MUX2_V are connected to the first terminals of the third resistor R3 and the first terminal of switch SWI2; the second terminals of switches MUX3_I and MUX3_V are connected to the first terminals of the fifth resistor R5 and the first terminal of switch SWI3; and the second terminals of switches MUX4_I and MUX4_V are connected to the first terminals of the seventh resistor R7 and the first terminal of switch SWI4.

[0049] The second terminal of the first resistor R1 and the second terminal of the switch SWI1 are both connected to the first terminal of the second resistor R2. The second terminal of the second resistor R2 is connected to the first terminal of the switch LD1, and the second terminal of the switch LD1 is grounded. The second terminal of the third resistor R3 and the second terminal of the switch SWI2 are both connected to the first terminal of the fourth resistor R4. The second terminal of the fourth resistor R4 is connected to the first terminal of the switch LD2, and the second terminal of the switch LD2 is grounded. The second terminal of the fifth resistor R5 and the second terminal of the switch SWI3 are both connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is connected to the first terminal of the switch LD3, and the second terminal of the switch LD3 is grounded. The second terminal of the seventh resistor R7 and the second terminal of the switch SWI4 are both connected to the first terminal of the eighth resistor R8. The second terminal of the eighth resistor R8 is connected to the first terminal of the switch LD4, and the second terminal of the switch LD4 is grounded.

[0050] That is, for the circuit structure described above, the n SWIs of the switch 300 under test require n switch detection interfaces and n LDs. Each switch detection interface includes a current-corresponding detection interface and a voltage-corresponding detection interface. Some ACUs cannot simultaneously accommodate n switch detection interfaces and n LDs, making it impossible to detect all switches in the vehicle, hindering the prediction and prevention of potential problems before a fault occurs, and increasing the risk of unexpected failures. Furthermore, simultaneously accommodating n switch detection interfaces and n LDs on the ACU increases costs.

[0051] The following is combined with Figure 2The working principle of the switch detection circuit 100 and the low-side drive circuit 200 for detecting the switch 300 under test is introduced. It can be understood that all the switches 300 under test in the vehicle share the same power supply 101 with voltage and current detection capability. By default, the MUX1_I, MUX1_V, MUX2_I, MUX2_V, MUX3_I, MUX3_V, MUX4_I, and MUX4_V of the switch detection circuit 100 and the LD1, LD2, LD3, and LD4 of the low-side drive circuit 200 are all in the off state.

[0052] The controller in the ACU (not shown in the figure) controls the switch MUX1_V to be in the ON state. After switch MUX1_V is turned on, the voltage detection port of power supply 101 can obtain the first voltage of switch SWI1 and determine whether the first voltage is greater than the voltage threshold. If the first voltage is greater than the voltage threshold, it is determined that there is a short circuit between switch SWI1 and the battery power line on the ACU harness / the power supply after the battery power passes through the start switch IGN. If the first voltage is less than or equal to the voltage threshold, it is determined that there is no short circuit between switch SWI1 and the battery power line on the ACU harness / the power supply after the battery power passes through the start switch IGN. The ON signal is a high-level signal, and the OFF signal is a low-level signal.

[0053] The controller in the ACU sends conduction signals to switches MUX1_V and MUX1_I to control them to be in the conducting state. After switches MUX1_V and MUX1_I are in the conducting state, the SRC output and current detection port of power supply 101 can obtain the first current of switch SWI1. Power supply 101 determines whether the first current is greater than the current threshold. If the first current is greater than the current threshold, it is determined that there is a short circuit between switch SWI1 and ground. If the first current is less than or equal to the current threshold, it is determined that there is no short circuit between switch SWI1 and ground.

[0054] When the first voltage is less than or equal to a voltage threshold and the first current is less than or equal to a current threshold, the ACU controller can send a conduction signal to switches MUX1_V, MUX1_I, and LD1 to control them to be in the conducting state. After switches MUX1_V, MUX1_I, and LD1 are in the conducting state, the SRC output and current detection port of power supply 101 can acquire the second voltage and second current of switch SWI1, calculate the first resistance value of switch SWI1 based on the second voltage and second current, and determine whether the first resistance value is greater than the first threshold. If the first resistance value is greater than the first threshold, a third signal is output, indicating an open circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. If the first resistance value is less than or equal to the first threshold, it is determined whether the first resistance value is greater than the second threshold. If the first resistance value is greater than the second threshold, a third signal is output. The system outputs a fourth signal, indicating that switch SWI1 is open. If the first resistance value is less than or equal to the second threshold, it checks whether the first resistance value is greater than the third threshold. If the first resistance value is greater than the third threshold, it outputs a fifth signal, indicating that the second voltage and second current are invalid. If the first resistance value is less than or equal to the third threshold, it checks whether the first resistance value is greater than the fourth threshold. If the first resistance value is greater than the fourth threshold, it outputs a sixth signal, indicating that switch SWI1 is closed. If the first resistance value is less than or equal to the fourth threshold, it outputs a seventh signal, indicating that there is a short circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303.

[0055] like Figure 2 As shown, the turn-on time of switch MUX1_V is earlier than that of switch MUX1_I, and the turn-on time of switch MUX1_I is earlier than that of switch LD1. A first resistance value less than or equal to a first threshold and greater than a second threshold, or less than or equal to a third threshold and greater than a fourth threshold, all indicate that the second voltage and second current are effective. After checking switch SWI1, a turn-off signal can be sent to switches MUX1_V, MUX1_I, and LD1 to turn them off.

[0056] It is understandable that when checking switches SWI2, SWI3, and SWI4, conduction signals can be sent sequentially to the detection interfaces and LDs connected to switches SWI2, SWI3, and SWI4 to perform a full diagnosis of switches SWI2, SWI3, and SWI4.

[0057] To address the issue that some ACUs cannot simultaneously accommodate n switch detection interfaces and n LDs due to limitations in the size, functionality, and cost of the integrated chips / circuits / PCBs used by the ACU, embodiments of this application provide a detection circuit, such as... Figure 3As shown, the detection circuit includes a detection module 301, an interface selection module 302, a driving module 303, and a switch to be tested 304. The detection module 301 is connected to the first end of the interface selection module 302, the second end of the interface selection module 302 is connected to the first end of the switch to be tested 304, and the second end of the switch to be tested 304 is connected to the first end of the driving module 303. The interface selection module 302 includes m interface units (e.g., the first interface unit 3021, the second interface unit 3022, and the m-th interface unit 302m), and the driving module 303 includes n driving units (e.g., the first driving unit 3031, the second driving unit 3032, and the n-th driving unit 302m). Unit 303n), the switch to be detected 304 includes i switch units (e.g., first switch unit 3041, second switch unit 3042, i-th drive unit 304i), m < i and / or n < i; when 1 ≤ m < i, the second end of the first interface unit 3021 in the m interface units is connected to the first end of multiple switch units in the i switch units, and the second end of multiple switch units is connected to multiple different drive units; when 1 ≤ n < i, the first end of the first drive unit 3031 in the n drive units is connected to the second end of multiple switch units in the i switch units, and the first end of multiple switch units is connected to the second end of multiple different interface units.

[0058] Thus, the interface unit in the interface selection module 302 and / or the drive unit in the drive module 303 can connect to multiple switch units in i switch units. That is, the interface unit in the interface selection module 302 and / or the drive unit in the drive module 303 can be reused during the detection process of the switch unit, thereby reducing the number of interface units and / or control units required in the detection circuit, i.e., reducing the number of electronic devices in the detection circuit, and reducing the size, chip function, and circuit cost of the integrated chip (circuit / PCB) used by the ACU.

[0059] In some embodiments, i ≤ m × n, meaning that m interface units and n interface units can detect at most i switches. For example, if m = 1 and n = 4, then at most 4 switch units can be detected; if m = 2 and n = 2, then at most 4 switch units can be detected; if m = 4 and n = 1, then at most 4 switch units can be detected; if m = 2 and n = 3, then at most 6 switch units can be detected.

[0060] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described clearly and in detail below with reference to the accompanying drawings.

[0061] Figure 4a A schematic diagram of a detection circuit with m=1, n=4, and i=4 is shown according to an embodiment of this application. Figure 4aThe detection circuit shown includes a detection module 301, an interface selection module 302, a drive module 303, a switch to be tested 304, and a control module 305 (not shown in the figure). The interface selection module 302 includes a first interface unit 3021, which includes a first voltage interface unit 3021a and a first current interface unit 3021b. The drive module 303 includes a first drive unit 3031, a second drive unit 3032, a third drive unit 3033, and a fourth drive unit 3034. The switch to be tested 304 includes a first switch unit 3041, a second switch unit 3042, a third switch unit 3043, and a fourth switch unit 3044. The control module 305 includes a controller.

[0062] The first end of the interface selection module 302 is connected to the first end of the detection module 301, that is, the first end of the first interface unit 3021 is connected to the first end of the detection module 301, or the first ends of the first voltage interface unit 3021a and the first current interface unit 3021b are both connected to the first end of the detection module 301. The second end of the interface selection module 302 is connected to the first end of the switch to be tested 304, that is, the second end of the first interface unit 3021 is connected to the first end of the switch to be tested 304, or the second ends of the first voltage interface unit 3021a and the first current interface unit 3021b are both connected to the first end of the switch to be tested 304, or the second ends of the first voltage interface unit 3021a and the first current interface unit 3021b are both connected to the first ends of the first switch unit 3041, the second switch unit 3042, the third switch unit 3043, and the fourth switch unit 3044.

[0063] The second end of the switch to be tested 304 is connected to the first end of the drive module 303. In some embodiments, the second end of the first switch unit 3041 is connected to the first end of the first drive unit 3031, the second end of the second switch unit 3042 is connected to the first end of the second drive unit 3032, the second end of the third switch unit 3043 is connected to the first end of the third drive unit 3033, and the second end of the fourth switch unit 3044 is connected to the first end of the fourth drive unit 3034.

[0064] The control module 305 is used to control the on and off states of the switches in the interface selection module 302 and the on and off states of the switches in the drive module 303.

[0065] In this embodiment, the detection module 301 includes a power supply 101 with current and voltage detection capabilities, a voltage detection port, and a current detection port; the first voltage interface unit 3021a includes a switch MUX1_V, the first current interface unit 3021b includes a switch MUX1_I, the first drive unit 3031 includes a switch LD1, the second drive unit 3032 includes a switch LD2, the third drive unit 3033 includes a switch LD3, and the fourth drive unit 3034 includes a switch LD4; the first switch unit 3041 includes a switch SWI1, a first resistor R1, and a second resistor R2; the second switch unit 3042 includes a switch SWI2, a third resistor R3, and a fourth resistor R4; the third switch unit 3043 includes a switch SWI3, a fifth resistor R5, and a sixth resistor R6; and the fourth switch unit 3044 includes a switch SWI4, a seventh resistor R7, and an eighth resistor R8.

[0066] In this embodiment, switch SWI1 is connected in parallel with the second resistor R2, switch SWI2 is connected in parallel with the fourth resistor R4, switch SWI3 is connected in parallel with the sixth resistor R6, and switch SWI4 is connected in parallel with the eighth resistor R8. That is... Figure 4b As shown, the first terminal of switch MUX1_V is connected to the voltage detection port, and the first terminal of switch MUX1_I is connected to the SRC output and current detection port; the second terminals of switch MUX1_V and switch MUX1_I are connected to the first terminals of the first resistor R1, the third resistor R3, the fifth resistor R5, and the seventh resistor R7.

[0067] The second terminal of the first resistor R1 is connected to the first terminal of the second resistor R2 and the first terminal of switch SWI1. The second terminal of the second resistor R2 and the second terminal of switch SWI1 are connected to the first terminal of switch LD1, and the second terminal of switch LD1 is grounded. The second terminal of the third resistor R3 is connected to the first terminal of the fourth resistor R4 and the first terminal of switch SWI2. The second terminal of the fourth resistor R4 and the second terminal of switch SWI2 are connected to the first terminal of switch LD2, and the second terminal of switch LD2 is grounded. The second terminal of the fifth resistor R5 is connected to the first terminal of the sixth resistor R6 and the first terminal of switch SWI3. The second terminal of the sixth resistor R6 and the second terminal of switch SWI3 are connected to the first terminal of switch LD3, and the second terminal of switch LD3 is grounded. The second terminal of the seventh resistor R7 is connected to the first terminal of the eighth resistor R8 and the first terminal of switch SWI4. The second terminal of the eighth resistor R8 and the second terminal of switch SWI4 are connected to the first terminal of switch LD4, and the second terminal of switch LD4 is grounded.

[0068] It is understood that in some other embodiments, switch SWI1 is connected in parallel with the first resistor R1, switch SWI2 is connected in parallel with the third resistor R3, switch SWI3 is connected in parallel with the fifth resistor R5, and switch SWI4 is connected in parallel with the seventh resistor R7. That is, the first terminal of switch MUX1_V is connected to the voltage detection port, and the first terminal of switch MUX1_I is connected to the SRC output and the current detection port; the second terminals of switch MUX1_V and switch MUX1_I are connected to the first terminals of the first resistor R1 and the first terminal of switch SWI1, the first terminal of the third resistor R3 and the first terminal of switch SWI2, the first terminal of the fifth resistor R5 and the first terminal of switch SWI3, and the first terminal of the seventh resistor R7 and the first terminal of switch SWI4.

[0069] The second terminal of the first resistor R1 and the second terminal of the switch SWI1 are both connected to the first terminal of the second resistor R2. The second terminal of the second resistor R2 is connected to the first terminal of the switch LD1, and the second terminal of the switch LD1 is grounded. The second terminal of the third resistor R3 and the second terminal of the switch SWI2 are both connected to the first terminal of the fourth resistor R4. The second terminal of the fourth resistor R4 is connected to the first terminal of the switch LD2, and the second terminal of the switch LD2 is grounded. The second terminal of the fifth resistor R5 and the second terminal of the switch SWI3 are both connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is connected to the first terminal of the switch LD3, and the second terminal of the switch LD3 is grounded. The second terminal of the seventh resistor R7 and the second terminal of the switch SWI4 are both connected to the first terminal of the eighth resistor R8. The second terminal of the eighth resistor R8 is connected to the first terminal of the switch LD4, and the second terminal of the switch LD4 is grounded.

[0070] The following is combined with Figure 5a right Figure 4b The working principle of the detection circuit shown is explained. It can be understood that, by default, switches MUX1_V, MUX1_I, LD1, LD2, LD3, and LD4 are all in the off state.

[0071] In this embodiment, the ACU control module 305 sends a turn-on signal to switch MUX1_V to control switch MUX1_V to be in the on state, and sends a turn-off signal to switches MUX1_I, LD1, LD2, LD3, and LD4 to control switches MUX1_I, LD1, LD2, LD3, and LD4 to be in the off state. After switch MUX1_V is turned on, the voltage detection port of power supply 101 can obtain the first voltage of switch SWI1 and determine whether the first voltage is greater than the voltage threshold. The first voltage represents the voltage of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 have not formed a closed loop with the switch 304 under test. If the first voltage is greater than the voltage threshold, a first signal is output. The first signal represents that there is a short circuit between at least one switch in the switch 304 under test and the battery power line / power supply of the battery power after the start switch IGN on the ACU harness. For example, if... Figure 4b In the example shown, the first signal indicates that at least one of the switches SWI1, SWI2, SWI3, and SWI4 is short-circuited with the battery power line / battery power supply on the ACU harness after passing through the start switch IGN. If the first voltage is less than or equal to a voltage threshold, it is determined that there is no short circuit between the switches SWI1, SWI2, SWI3, and SWI4 and the battery power line / battery power supply on the ACU harness after passing through the start switch IGN. The on signal is a high-level signal, and the off signal is a low-level signal.

[0072] The ACU control module 305 sends conduction signals to switches MUX1_V and MUX1_I to control them to be in the conduction state, and sends deactivation signals to switches LD1, LD2, LD3, and LD4 to control them to be in the deactivation state. After switches MUX1_V and MUX1_I are in the conduction state, the SRC output and current detection port of the power supply 101 can obtain the first current of switch SWI1. The first current represents the current of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 have not formed a closed loop with the switch under test 304. The power supply 101 determines whether the first current is greater than the current threshold. If the first current is greater than the current threshold, it outputs a second signal. The second signal represents that there is a short circuit between at least one switching unit and ground in the switch under test 304. For example, ... Figure 4bIn the example shown, the first signal can characterize the presence of a short circuit between at least one of the switches SWI1, SWI2, SWI3, and SWI4 in the switch to be detected and ground. If the first current is less than or equal to a current threshold, it is determined that there is no short circuit between switches SWI1, SWI2, SWI3, and SWI4 and ground.

[0073] When the first voltage is less than or equal to a voltage threshold and the first current is less than or equal to a current threshold, the ACU's control module 305 can send a turn-on signal to switches MUX1_V, MUX1_I, and LD1 to control them to be in a conducting state; and send a turn-off signal to switches LD2, LD3, and LD4 to control them to be in a disconnected state. After switches MUX1_V, MUX1_I, and LD1 are in a conducting state, the SRC output and current detection port of the power supply 101 can obtain the second voltage and second current of switch SWI1; the second voltage is the voltage of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 form a closed loop with the switch 304 under test, and the second current is the current of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 form a closed loop with the switch 304 under test. Power supply 101 calculates the first resistance value of switch SWI1 based on the second voltage and the second current, and determines whether the first resistance value is greater than the first threshold. If the first resistance value is greater than the first threshold, a third signal is output, indicating that there is an open circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. If the first resistance value is less than or equal to the first threshold, it determines whether the first resistance value is greater than the second threshold. If the first resistance value is greater than the second threshold, a fourth signal is output, indicating that switch SWI1 is open. If the first resistance value is less than or equal to the second threshold, it determines whether the first resistance value is greater than the third threshold. If the first resistance value is greater than the third threshold, a fifth signal is output, indicating that the second voltage and the second current are invalid. If the first resistance value is less than or equal to the third threshold, it determines whether the first resistance value is greater than the fourth threshold. If the first resistance value is greater than the fourth threshold, a sixth signal is output, indicating that switch SWI1 is closed. If the first resistance value is less than or equal to the fourth threshold, a seventh signal is output, indicating that there is a short circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. It is understandable that a first resistance value less than or equal to the first threshold and greater than the second threshold, or less than or equal to the third threshold and greater than the fourth threshold, all indicate that the second voltage and the second current are effective.

[0074] like Figure 5aAs shown, the turn-on time of switch MUX1_V is earlier than the turn-on time of switch MUX1_I, and the turn-on time of switch MUX1_I is earlier than the turn-on time of switch LD1. In this embodiment, after the check of switch SWI1 is completed, a turn-off signal can be sent to switches MUX1_V, MUX1_I, and LD1 to turn off switches MUX1_V, MUX1_I, and LD1.

[0075] It is understandable that when checking switches SWI2, SWI3, and SWI4, conduction signals can be sent sequentially to the detection interfaces and LDs connected to switches SWI2, SWI3, and SWI4 to perform a full diagnosis of switches SWI2, SWI3, and SWI4.

[0076] For example, when checking switch SWI2, control module 305 can send conduction signals to switches MUX1_V, MUX1_I, and LD2 in sequence; when checking switch SWI3, control module 305 can send conduction signals to switches MUX1_V, MUX1_I, and LD3 in sequence; when checking switch SWI4, control module 305 can send conduction signals to switches MUX1_V, MUX1_I, and LD4 in sequence.

[0077] In some embodiments, after the switch SWI1 has been checked, such as Figure 5b As shown, a shutdown signal can be sent only to switch LD1 to shut it off. When checking switches SWI2, SWI3, and SWI4, a turn-on signal can be sent sequentially to the LDs connected to switches SWI2, SWI3, and SWI4 to perform a full diagnostic on switches SWI2, SWI3, and SWI4.

[0078] For example, when checking switch SWI2, control module 305 can send a conduction signal to switch LD2; when checking switch SWI3, control module 305 can send a conduction signal to switch LD3; when checking switch SWI4, control module 305 can send a conduction signal to switch LD4.

[0079] Figure 6a A schematic diagram of a detection circuit with m=4, n=1, and i=4 is shown according to an embodiment of this application. Figure 6aThe detection module 301 of the detection circuit shown includes a control module 305 (not shown in the figure), a detection module 301, an interface selection module 302, a switch to be tested 304, and a drive module 303; the interface selection module 302 includes a first interface unit 3021, a second interface unit 3022, a third interface unit 3023, and a fourth interface unit 3024. The first interface unit 3021 includes a first voltage interface unit 3021a and a first current interface unit 3021b, and the second interface unit 3022 includes a second voltage interface unit 3021a and a first current interface unit 3021b. Interface unit 3022a and second current interface unit 3022b, third interface unit 3023 including third voltage interface unit 3023a and third current interface unit 3023b, fourth interface unit 3024 including fourth voltage interface unit 3024a and fourth current interface unit 3024b; drive module 303 including first drive unit 3031; switch to be detected 304 including first switch unit 3041, second switch unit 3042, third switch unit 3043 and fourth switch unit 3044. Control module 305 includes a controller.

[0080] The first end of the interface selection module 302 is connected to the first end of the detection module 301, that is, the first end of the first interface unit 3021, the first end of the second interface unit 3022, the first end of the third interface unit 3023, and the first end of the fourth interface unit 3024 are connected to the first end of the detection module 301.

[0081] The second end of the interface selection module 302 is connected to the first end of the switch to be tested 304. In some embodiments, the second end of the first interface unit 3021 is connected to the first end of the first switch unit 3041, the second end of the second interface unit 3022 is connected to the first end of the second switch unit 3042, the second end of the third interface unit 3023 is connected to the first end of the third switch unit 3043, and the second end of the fourth interface unit 3024 is connected to the first end of the fourth switch unit 3044.

[0082] The second end of the switch to be tested 304 is connected to the first end of the drive module 303. In some embodiments, the second ends of the first switch unit 3041, the second ends of the second switch unit 3042, the third switch unit 3043, and the fourth switch unit 3044 are connected to the first end of the first drive unit 3031.

[0083] The control module 305 is used to control the on and off states of the switches in the interface selection module 302 and the on and off states of the switches in the drive module 303.

[0084] In this embodiment, the detection module 301 includes a power supply 101 with current and voltage detection capabilities, a voltage detection port, and a current detection port; the first voltage interface unit 3021a includes a switch MUX1_V, the first current interface unit 3021b includes a switch MUX1_I, the second voltage interface unit 3022a includes a switch MUX2_V, the first current interface unit 3021b includes a switch MUX2_I, the third voltage interface unit 3023a includes a switch MUX3_V, the third current interface unit 3023b includes a switch MUX3_I, and the fourth voltage... Interface unit 3024a includes switch MUX4_V; fourth current interface unit 3024b includes switch MUX4_I; first drive unit 3031 includes switch LD1; first switch unit 3041 includes switch SWI1, first resistor R1, and second resistor R2; second switch unit 3042 includes switch SWI2, third resistor R3, and fourth resistor R4; third switch unit 3043 includes switch SWI3, fifth resistor R5, and sixth resistor R6; fourth switch unit 3044 includes switch SWI4, seventh resistor R7, and eighth resistor R8.

[0085] In this embodiment, switch SWI1 is connected in parallel with the second resistor R2, switch SWI2 is connected in parallel with the fourth resistor R4, switch SWI3 is connected in parallel with the sixth resistor R6, and switch SWI4 is connected in parallel with the eighth resistor R8. That is... Figure 6b As shown, the first terminals of switches MUX1_V, MUX2_V, MUX3_V, and MUX4_V are connected to the voltage detection port, and the first terminals of switches MUX1_I, MUX2_I, MUX3_I, and MUX4_I are connected to the current detection port. The second terminals of switches MUX1_V and MUX1_I are connected to the first terminal of the first resistor R1, the second terminals of switches MUX2_V and MUX2_I are connected to the first terminal of the third resistor R3, the second terminals of switches MUX3_V and MUX3_I are connected to the first terminal of the fifth resistor R5, and the second terminals of switches MUX4_V and MUX4_I are connected to the first terminal of the seventh resistor R7.

[0086] The second terminal of the first resistor R1 is connected to the first terminal of the second resistor R2 and the first terminal of switch SWI1. The second terminal of the second resistor R2 and the second terminal of switch SWI1 are connected to the first terminal of switch LD1. The second terminal of the third resistor R3 is connected to the first terminal of the fourth resistor R4 and the first terminal of switch SWI2. The second terminal of the fourth resistor R4 and the second terminal of switch SWI2 are connected to the first terminal of switch LD1. The second terminal of the fifth resistor R5 is connected to the first terminal of the sixth resistor R6 and the first terminal of switch SWI3. The second terminal of the sixth resistor R6 and the second terminal of switch SWI3 are connected to the first terminal of switch LD1. The second terminal of the seventh resistor R7 is connected to the first terminal of the eighth resistor R8 and the first terminal of switch SWI4. The second terminal of the eighth resistor R8 and the second terminal of switch SWI4 are connected to the first terminal of switch LD1. The second terminal of switch LD1 is grounded.

[0087] It is understood that in some other embodiments, switch SWI1 is connected in parallel with the first resistor R1, switch SWI2 is connected in parallel with the third resistor R3, switch SWI3 is connected in parallel with the fifth resistor R5, and switch SWI4 is connected in parallel with the seventh resistor R7. Specifically, the first terminals of switches MUX1_V, MUX2_V, MUX3_V, and MUX4_V are connected to the voltage detection port; the first terminals of switches MUX1_I, MUX2_I, MUX3_I, and MUX4_I are connected to the current detection port; the second terminals of switches MUX1_V and MUX1_I are connected to the first terminals of the first resistor R1 and the first terminal of switch SWI1; the second terminals of switches MUX2_V and MUX2_I are connected to the first terminals of the third resistor R3 and the first terminal of switch SWI2; the second terminals of switches MUX3_V and MUX3_I are connected to the first terminals of the fifth resistor R5 and the first terminal of switch SWI3; and the second terminals of switches MUX4_V and MUX4_I are connected to the first terminals of the seventh resistor R7 and the first terminal of switch SWI4.

[0088] The second terminal of the first resistor R1 and the second terminal of the switch SWI1 are both connected to the first terminal of the second resistor R2. The second terminal of the second resistor R2 is connected to the first terminal of the switch LD1. The second terminal of the third resistor R3 and the second terminal of the switch SWI2 are both connected to the first terminal of the fourth resistor R4. The second terminal of the fourth resistor R4 is connected to the first terminal of the switch LD1. The second terminal of the fifth resistor R5 and the second terminal of the switch SWI3 are both connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is connected to the first terminal of the switch LD1. The second terminal of the seventh resistor R7 and the second terminal of the switch SWI4 are both connected to the first terminal of the eighth resistor R8. The second terminal of the eighth resistor R8 is connected to the first terminal of the switch LD1. The second terminal of the switch LD1 is grounded.

[0089] The following is combined with Figure 7 right Figure 6b The working principle of the detection circuit shown is explained. It can be understood that, by default, switches MUX1_V, MUX1_I, MUX2_V, MUX2_I, MUX3_V, MUX3_I, MUX4_V, MUX4_I, and LD1 are all in the off state.

[0090] In this embodiment, the ACU control module 305 sends a turn-on signal to switch MUX1_V to control switch MUX1_V to be in the on state, and sends a turn-off signal to switches MUX1_I, MUX2_V, MUX2_I, MUX3_V, MUX3_I, MUX4_V, MUX4_I, and LD1 to control switches MUX1_I, MUX2_V, MUX2_I, MUX3_V, MUX3_I, MUX4_V, MUX4_I, and LD1 to be in the off state. After switch MUX1_V is turned on, the voltage detection port of power supply 101 can obtain the first voltage of switch SWI1 and determine whether the first voltage is greater than the voltage threshold. The first voltage represents the voltage of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 have not formed a closed loop with the switch 304 to be detected. If the first voltage is greater than the voltage threshold, a short circuit is determined between switch SWI1 and the battery power line / power supply of the battery power supply after passing through the start switch IGN on the ACU harness. A first signal is output, indicating that at least one switching unit in the switch 304 under test has a short circuit between the battery power line / power supply of the battery power supply after passing through the start switch IGN on the ACU harness. For example, if... Figure 6b In the example shown, the first signal indicates that at least one of the switches SWI1, SWI2, SWI3, and SWI4 in the switch to be detected (SWI4) is short-circuited with the battery power line / battery power supply after the start switch IGN on the ACU harness. If the first voltage is less than or equal to a voltage threshold, it is determined that there is no short circuit between switch SWI1 and the battery power line / battery power supply after the start switch IGN on the ACU harness. The on signal is a high-level signal, and the off signal is a low-level signal.

[0091] The ACU's control module 305 sends conduction signals to switches MUX1_V and MUX1_I to control them to be in the conduction state, and sends shutdown signals to switches MUX2_V, MUX2_I, MUX3_V, MUX3_I, MUX4_V, MUX4_I, and LD1 to control them to be in the off state. After switches MUX1_V and MUX1_I are in the conduction state, the current detection port of the power supply 101 can obtain the first current of switch SWI1. The first current represents the current of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 have not formed a closed loop with the switch 304 under test. Power supply 101 determines whether the first current is greater than the current threshold. If the first current is greater than the current threshold, it determines that there is a short circuit between switch SWI1 and ground, and outputs a second signal. The second signal indicates that there is a short circuit between at least one switching unit in the switch to be detected 304 and ground. For example, ... Figure 6b In the example shown, the first signal can characterize the presence of a short circuit between at least one of switches SWI1, SWI2, SWI3, and SWI4 and ground. If the first current is less than or equal to a current threshold, it is determined that there is no short circuit between switch SWI1 and ground.

[0092] When the first voltage is less than or equal to the voltage threshold and the first current is less than or equal to the current threshold, the ACU control module 305 can send a turn-on signal to switches MUX1_V, MUX1_I, and LD1 to control switches MUX1_V, MUX1_I, and LD1 to be in the turn-on state; and send a turn-off signal to switches MUX2_V, MUX2_I, MUX3_V, MUX3_I, MUX4_V, and MUX4_I to control switches MUX2_V, MUX2_I, MUX3_V, MUX3_I, MUX4_V, and MUX4_I to be in the turn-off state. After switches MUX1_V, MUX1_I, and LD1 are in the ON state, the SRC output and current detection port of power supply 101 can obtain the second voltage and second current of switch SWI1. The second voltage is the voltage of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 form a closed loop with the switch under test 304, and the second current is the current of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 form a closed loop with the switch under test 304. Power supply 101 calculates the first resistance value of switch SWI1 based on the second voltage and the second current, and determines whether the first resistance value is greater than the first threshold. If the first resistance value is greater than the first threshold, a third signal is output, indicating that there is an open circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. If the first resistance value is less than or equal to the first threshold, it determines whether the first resistance value is greater than the second threshold. If the first resistance value is greater than the second threshold, a fourth signal is output, indicating that switch SWI1 is open. If the first resistance value is less than or equal to the second threshold, it determines whether the first resistance value is greater than the third threshold. If the first resistance value is greater than the third threshold, a fifth signal is output, indicating that the second voltage and the second current are invalid. If the first resistance value is less than or equal to the third threshold, it determines whether the first resistance value is greater than the fourth threshold. If the first resistance value is greater than the fourth threshold, a sixth signal is output, indicating that switch SWI1 is closed. If the first resistance value is less than or equal to the fourth threshold, a seventh signal is output, indicating that there is a short circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. It is understandable that a first resistance value less than or equal to the first threshold and greater than the second threshold, or less than or equal to the third threshold and greater than the fourth threshold, all indicate that the second voltage and the second current are effective.

[0093] like Figure 7As shown, the turn-on time of switch MUX1_V is earlier than the turn-on time of switch MUX1_I, and the turn-on time of switch MUX1_I is earlier than the turn-on time of switch LD1. In this embodiment, after the check of switch SWI1 is completed, a turn-off signal can be sent to switches MUX1_V, MUX1_I, and LD1 to turn off switches MUX1_V, MUX1_I, and LD1.

[0094] It is understandable that when checking switches SWI2, SWI3, and SWI4, conduction signals can be sent sequentially to the detection interfaces and LDs connected to switches SWI2, SWI3, and SWI4 to perform a full diagnosis of switches SWI2, SWI3, and SWI4.

[0095] For example, when checking switch SWI2, control module 305 can send conduction signals to switch MUX2_V, switch MUX2_I and LD1 in sequence; when checking switch SWI3, control module 305 can send conduction signals to switch MUX3_V, switch MUX3_I and LD1 in sequence; when checking switch SWI4, control module 305 can send conduction signals to switch MUX4_V, switch MUX4_I and LD1 in sequence.

[0096] Figure 8a A schematic diagram of a detection circuit with m=2, n=2, and i=4 is shown according to an embodiment of this application. Figure 8a The detection module 301 of the detection circuit shown includes a control module 305 (not shown in the figure), a detection module 301, an interface selection module 302, a switch to be tested 304, and a drive module 303. The interface selection module 302 includes a first interface unit 3021 and a second interface unit 3022. In some embodiments, the first interface unit 3021 includes a first voltage interface unit 3021a and a first current interface unit 3021b, and the second interface unit 3022 includes a second voltage interface unit 3022a and a second current interface unit 3022b. The drive module 303 includes a first drive unit 3031 and a second drive unit 3032. The switch to be tested 304 includes a first switch unit 3041, a second switch unit 3042, a third switch unit 3043, and a fourth switch unit 3044. The control module 305 includes a controller.

[0097] In this embodiment, the first end of the interface selection module 302 is connected to the first end of the detection module 301, that is, the first end of the first interface unit 3021 and the first end of the second interface unit 3022 are connected to the first end of the detection module 301. The second end of the interface selection module 302 is connected to the first end of the switch to be tested 304. In some embodiments, the second end of the first interface unit 3021 is connected to the first end of the first switch unit 3041 and the first end of the second switch unit 3042, and the second end of the second interface unit 3022 is connected to the first end of the third switch unit 3043 and the first end of the fourth switch unit 3044.

[0098] The second end of the switch to be tested 304 is connected to the first end of the drive module 303. In some embodiments, the second end of the first switch unit 3041 is connected to the first end of the first drive unit 3031, the second end of the second switch unit 3042 is connected to the first end of the second drive unit 3032, the second end of the third switch unit 3043 is connected to the first end of the first drive unit 3031, and the second end of the fourth switch unit 3044 is connected to the first end of the second drive unit 3032.

[0099] The control module 305 is used to control the on and off states of the switches in the interface selection module 302 and the on and off states of the switches in the drive module 303.

[0100] In this embodiment, the detection module 301 includes a power supply 101 with current and voltage detection capabilities, a voltage detection port, and a current detection port; the first voltage interface unit 3021a includes a switch MUX1_V, the first current interface unit 3021b includes a switch MUX1_I, the second voltage interface unit 3022a includes a switch MUX2_V, the second current interface unit 3022b includes a switch MUX2_I, the first drive unit 3031 includes a switch LD1, and the second drive unit 3032 includes a switch LD2; the first switch unit 3041 includes a switch SWI1, a first resistor R1, and a second resistor R2; the second switch unit 3042 includes a switch SWI2, a third resistor R3, and a fourth resistor R4; the third switch unit 3043 includes a switch SWI3, a fifth resistor R5, and a sixth resistor R6; and the fourth switch unit 3044 includes a switch SWI4, a seventh resistor R7, and an eighth resistor R8.

[0101] In this embodiment, switch SWI1 is connected in parallel with the second resistor R2, switch SWI2 is connected in parallel with the fourth resistor R4, switch SWI3 is connected in parallel with the sixth resistor R6, and switch SWI4 is connected in parallel with the eighth resistor R8. That is... Figure 8bAs shown, the first terminals of switches MUX1_V and MUX2_V are connected to the voltage detection port; the first terminals of switches MUX1_I and MUX2_V are connected to the SRC output and current detection port; the second terminals of switches MUX1_V and MUX1_I are connected to the first terminals of the first resistor R1 and the third resistor R3; the second terminals of switches MUX2_V and MUX2_I are connected to the first terminals of the fifth resistor R5 and the seventh resistor R7.

[0102] The second terminal of the first resistor R1 is connected to the first terminal of the second resistor R2 and the first terminal of switch SWI1. The second terminal of the second resistor R2 and the second terminal of switch SWI1 are connected to the first terminal of switch LD1, and the second terminal of switch LD1 is grounded. The second terminal of the third resistor R3 is connected to the first terminal of the fourth resistor R4 and the first terminal of switch SWI2. The second terminal of the fourth resistor R4 and the second terminal of switch SWI2 are connected to the first terminal of switch LD2, and the second terminal of switch LD2 is grounded. The second terminal of the fifth resistor R5 is connected to the first terminal of the sixth resistor R6 and the first terminal of switch SWI3. The second terminal of the sixth resistor R6 and the second terminal of switch SWI3 are connected to the first terminal of switch LD1, and the second terminal of switch LD1 is grounded. The second terminal of the seventh resistor R7 is connected to the first terminal of the eighth resistor R8 and the first terminal of switch SWI4. The second terminal of the eighth resistor R8 and the second terminal of switch SWI4 are connected to the first terminal of switch LD2, and the second terminal of switch LD2 is grounded.

[0103] It is understood that in some other embodiments, switch SWI1 is connected in parallel with the first resistor R1, switch SWI2 is connected in parallel with the third resistor R3, switch SWI3 is connected in parallel with the fifth resistor R5, and switch SWI4 is connected in parallel with the seventh resistor R7. That is, the first terminals of switches MUX1_V and MUX2_V are connected to the voltage detection port, and the first terminals of switches MUX1_I and MUX2_V are connected to the SRC output and current detection port; the second terminals of switches MUX1_V and MUX1_I are connected to the first terminals of the first resistor R1 and switch SWI1, the first terminal of the third resistor R3 and switch SWI2; the second terminals of switches MUX2_V and MUX2_I are connected to the first terminals of the fifth resistor R5 and switch SWI3, the first terminal of the seventh resistor R7 and switch SWI4.

[0104] The second terminal of the first resistor R1 and the second terminal of the switch SWI1 are both connected to the first terminal of the second resistor R2. The second terminal of the second resistor R2 is connected to the first terminal of the switch LD1, and the second terminal of the switch LD1 is grounded. The second terminal of the third resistor R3 and the second terminal of the switch SWI2 are both connected to the first terminal of the fourth resistor R4. The second terminal of the fourth resistor R4 is connected to the first terminal of the switch LD2, and the second terminal of the switch LD2 is grounded. The second terminal of the fifth resistor R5 and the second terminal of the switch SWI3 are both connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is connected to the first terminal of the switch LD1, and the second terminal of the switch LD1 is grounded. The second terminal of the seventh resistor R7 and the second terminal of the switch SWI4 are both connected to the first terminal of the eighth resistor R8. The second terminal of the eighth resistor R8 is connected to the first terminal of the switch LD2, and the second terminal of the switch LD2 is grounded.

[0105] The following is combined with Figure 9 right Figure 8b The working principle of the detection circuit shown is explained. It can be understood that, by default, switches MUX1_V, MUX1_I, MUX2_V, MUX2_I, LD1, and LD2 are all in the off state.

[0106] In this embodiment, the control module of the electronic device used in the ACU sends a conduction signal to switch MUX1_V to control switch MUX1_V to be in the conduction state, and sends a turn-off signal to switches MUX1_I, MUX2_V, MUX2_I, LD1, and LD2 to control switches MUX1_I, MUX2_V, MUX2_I, LD1, and LD2 to be in the off state. After switch MUX1_V is turned on, the voltage detection port of power supply 101 can obtain the first voltage of switch SWI1 and determine whether the first voltage is greater than the voltage threshold. The first voltage represents the voltage of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 have not formed a closed loop with the switch 304 to be detected. If the first voltage is greater than the voltage threshold, a short circuit is determined between switch SWI1 and the battery power line / power supply of the battery power supply after passing through the start switch IGN on the ACU harness. A first signal is output, indicating that at least one switching unit in the switch 304 under test has a short circuit between the battery power line / power supply of the battery power supply after passing through the start switch IGN on the ACU harness. For example, if... Figure 8bIn the example shown, the first signal indicates that at least one of the switches SWI1, SWI2, SWI3, and SWI4 is short-circuited with the battery power supply line / battery power supply on the ACU harness after passing through the start switch IGN. If the first voltage is less than or equal to a voltage threshold, it is determined that there is no short circuit between the switches SWI1, SWI2, SWI3, and SWI4 and the battery power supply line / battery power supply on the ACU harness after passing through the start switch IGN. The on signal is a high-level signal, and the off signal is a low-level signal.

[0107] In the ACU, the control module 305 sends conduction signals to switches MUX1_V and MUX1_I to control them to be in the conduction state, and sends turn-off signals to switches MUX2_V, MUX2_I, LD1, and LD2 to control them to be in the off state. After switches MUX1_V and MUX1_I are in the conduction state, the SRC output and current detection port of the power supply 101 can obtain the first current of switch SWI1. The first current represents the current of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 have not formed a closed loop with the switch under test 304. The power supply 101 determines whether the first current is greater than the current threshold. If the first current is greater than the current threshold, it determines that there is a short circuit between switch SWI1 and ground, and outputs a second signal. The second signal represents that there is a short circuit between at least one switching unit in the switch under test 304 and ground. For example, if... Figure 8b In the example shown, the first signal can characterize the presence of a short circuit between at least one of switches SWI1, SWI2, SWI3, and SWI4 and ground. If the first current is less than or equal to a current threshold, it is determined that there is no short circuit between switches SWI1, SWI2, SWI3, and SWI4 and ground.

[0108] When the first voltage is less than or equal to a voltage threshold and the first current is less than or equal to a current threshold, the ACU's control module 305 can send a turn-on signal to switches MUX1_V, MUX1_I, and LD1 to control them to be in a conducting state; and send a turn-off signal to switches MUX2_V, MUX2_I, and LD2 to control them to be in a disconnected state. After switches MUX1_V, MUX1_I, and LD1 are in a conducting state, the SRC output and current detection port of the power supply 101 can acquire the second voltage and second current of switch SWI1; the second voltage is the voltage of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 form a closed loop with the switch 304 under test; the second current is the current of switch SWI1 when the detection module 301, interface selection module 302, and drive module 303 form a closed loop with the switch 304 under test. Power supply 101 calculates the first resistance value of switch SWI1 based on the second voltage and the second current, and determines whether the first resistance value is greater than the first threshold. If the first resistance value is greater than the first threshold, a third signal is output, indicating that there is an open circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. If the first resistance value is less than or equal to the first threshold, it determines whether the first resistance value is greater than the second threshold. If the first resistance value is greater than the second threshold, a fourth signal is output, indicating that switch SWI1 is open. If the first resistance value is less than or equal to the second threshold, it determines whether the first resistance value is greater than the third threshold. If the first resistance value is greater than the third threshold, a fifth signal is output, indicating that the second voltage and the second current are invalid. If the first resistance value is less than or equal to the third threshold, it determines whether the first resistance value is greater than the fourth threshold. If the first resistance value is greater than the fourth threshold, a sixth signal is output, indicating that switch SWI1 is closed. If the first resistance value is less than or equal to the fourth threshold, a seventh signal is output, indicating that there is a short circuit between the second terminal of interface selection module 302 and the first terminal of drive module 303. It is understandable that a first resistance value less than or equal to the first threshold and greater than the second threshold, or less than or equal to the third threshold and greater than the fourth threshold, all indicate that the second voltage and the second current are effective.

[0109] like Figure 9 As shown, the turn-on time of switch MUX1_V is earlier than the turn-on time of switch MUX1_I, and the turn-on time of switch MUX1_I is earlier than the turn-on time of switch LD1. In this embodiment, after the check of switch SWI1 is completed, a turn-off signal can be sent to switches MUX1_V, MUX1_I, and LD1 to turn off switches MUX1_V, MUX1_I, and LD1.

[0110] It is understandable that when checking switches SWI2, SWI3, and SWI4, conduction signals can be sent sequentially to the detection interfaces and LDs connected to switches SWI2, SWI3, and SWI4 to perform a full diagnosis of switches SWI2, SWI3, and SWI4.

[0111] For example, when checking switch SWI2, control module 305 can send conduction signals to switches MUX1_V, MUX1_I, and LD2 in sequence; when checking switch SWI3, control module 305 can send conduction signals to switches MUX2_V, MUX2_I, and LD1 in sequence; when checking switch SWI4, control module 305 can send conduction signals to switches MUX2_V, MUX2_I, and LD2 in sequence.

[0112] This application also provides an airbag controller, including the detection circuit described above.

[0113] This application also provides an in-vehicle device, including the aforementioned airbag controller.

[0114] This application also provides a vehicle including the above-described vehicle-mounted equipment.

[0115] According to the embodiments of this application, Figure 10 A block diagram of an in-vehicle device 1300 based on a system-on-chip (SOC) is shown. Figure 10 In this designation, similar components share the same reference numerals. Additionally, the dashed box is an optional feature for more advanced SOCs. Figure 10 In this embodiment, the in-vehicle device 1300 includes: an interconnect unit 1350 coupled to a processor 1315; a system proxy unit 1370; a bus controller unit 1380; an integrated memory controller unit 1340; a group or one or more coprocessors 1320, which may include integrated graphics logic, an image processor, an audio processor, and a video processor; a static random-access memory (SRAM) unit 1330; and a direct memory access (DMA) unit 1360. In one embodiment, the coprocessor 1320 includes a dedicated processor, such as, for example, a network or communication processor, a compression engine, or an embedded processor.

[0116] In some cases, the disclosed embodiments may be implemented in hardware, firmware, software, or any combination thereof. The disclosed embodiments may also be implemented as instructions carried or stored thereon on one or more temporary or non-temporary machine-readable (e.g., computer-readable) storage media, which may be read and executed by one or more processors. For example, the instructions may be distributed via a network or through other computer-readable media. Therefore, machine-readable media may include any mechanism for storing or transmitting information in a machine-readable (e.g., computer-readable) form, including but not limited to floppy disks, optical disks, CD-ROMs, compact disc-read-only memory (CD-ROMs), magneto-optical disks, read-only memory (ROM), random access memory (RAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic cards or optical cards, flash memory, or tangible machine-readable storage for transmitting information (e.g., carrier waves, infrared signals, digital signals, etc.) using the Internet in the form of electrical, optical, acoustic, or other forms of propagated signals. Therefore, machine-readable media include any type of machine-readable medium suitable for storing or transmitting electronic instructions or information in a machine-readable (e.g., computer-readable) form.

[0117] In the accompanying drawings, some structural or methodological features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order may not be necessary. Rather, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. Furthermore, the inclusion of structural or methodological features in a particular figure does not imply that such features are required in all embodiments, and in some embodiments, these features may be omitted or may be combined with other features.

[0118] It should be noted that all units / modules mentioned in the device embodiments of this application are logical units / modules. Physically, a logical unit / module can be a physical unit / module, a part of a physical unit / module, or a combination of multiple physical units / modules. The physical implementation of these logical units / modules themselves is not the most important factor; the combination of functions implemented by these logical units / modules is the key to solving the technical problems proposed in this application. Furthermore, to highlight the innovative aspects of this application, the above-described device embodiments of this application have not introduced units / modules that are not closely related to solving the technical problems proposed in this application. This does not mean that the above-described device embodiments do not contain other units / modules.

[0119] It should be noted that, in the examples and specification of this patent, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0120] Although this application has been illustrated and described with reference to certain preferred embodiments thereof, those skilled in the art should understand that various changes in form and detail may be made thereto without departing from the spirit and scope of this application.

Claims

1. A detection circuit, characterized in that, It includes a detection module, an interface selection module, a driver module, and a switch to be tested. The detection module is connected to the first end of the interface selection module, the second end of the interface selection module is connected to the first end of the switch to be tested, and the second end of the switch to be tested is connected to the first end of the driver module. The interface selection module includes m interface units, the driving module includes n driving units, and the switch to be detected includes i switching units, where m < i and / or n < i; When 1≤m<i, the second end of the first interface unit in the m interface units is connected to the first end of the multiple switch units in the i switch units, and the second end of the multiple switch units is connected to multiple different drive units. When 1≤n<i, the first end of the first driving unit among the n driving units is connected to the second end of the multiple switching units among the i switching units, and the first end of the multiple switching units is connected to the second end of the multiple different interface units.

2. The detection circuit according to claim 1, characterized in that, i≤m×n.

3. The detection circuit according to claim 1, characterized in that, The first interface unit includes a first voltage interface unit and a first current interface unit. The first voltage interface unit is connected to the voltage detection terminal of the detection module, and the first current interface unit is connected to the current detection terminal of the detection module. The second terminals of the first voltage interface unit and the first current interface unit are both connected to the first terminal of the first switch unit among the i switch units; The second end of the first switching unit is connected to the first end of the first driving unit among the n driving units.

4. The detection circuit according to claim 3, characterized in that, The first switching unit includes a first switch, a first resistor, and a second resistor; the first voltage interface unit includes a second switch; the first current interface unit includes a third switch; and the first drive unit includes a fourth switch. The second terminals of both the second and third switches are connected to the first terminal of the first resistor. The second terminal of the first resistor is connected to both the first terminal of the second resistor and the first terminal of the first switch. The second terminal of both the second resistor and the second terminal of the first switch are connected to the first terminal of the fourth switch. The second terminal of the second switch and the second terminal of the third switch are both connected to the first resistor and the first terminal of the first switch. The second terminal of the first resistor and the first switch are connected to the first terminal of the second resistor. The second terminal of the second resistor is connected to the first terminal of the fourth switch.

5. The detection circuit according to claim 4, characterized in that, It also includes a control module; The control module is used to control the second switch to be in the on state and to control the third and fourth switches to be in the off state. The detection module is used to detect that the first voltage corresponding to the first switch is greater than the voltage threshold and output a first signal, wherein the first signal indicates that there is a short circuit between at least one switching unit and the power supply in the switch to be detected.

6. The detection circuit according to claim 5, characterized in that, include: The control module is used to control the second switch and the third switch to be in the on state, and to control the fourth switch to be in the off state; The detection module is used to detect that the first current corresponding to the first switch is greater than the current threshold and output a second signal, wherein the second signal indicates that there is a short circuit between at least one switch unit and ground in the switch to be detected.

7. The detection circuit according to claim 5, characterized in that, include: When the first voltage is less than or equal to a voltage threshold and the first current is less than or equal to a current threshold, the control module controls the second switch, the third switch, and the fourth switch to be in the ON state. The detection module is used to detect the second voltage and the second current corresponding to the first switch; The detection module is used to output a third signal when the ratio of the second voltage to the second current is greater than a first threshold. The third signal indicates that there is an open circuit between the second terminal of the interface selection module and the first terminal of the drive module. The detection module is used to output a fourth signal when the ratio of the second voltage to the second current is less than or equal to the first threshold and greater than the second threshold, the fourth signal indicating that the first switch is open; The detection module is used to output a fifth signal when the ratio of the second voltage to the second current is less than or equal to the second threshold and greater than the third threshold. The fifth signal indicates that the second voltage and the second current are invalid. The detection module is used to output a sixth signal when the ratio of the second voltage to the second current is less than or equal to the third threshold and greater than the fourth threshold, the sixth signal indicating that the first switch is closed; The detection module is used to output a seventh signal when the ratio of the second voltage to the second current is less than or equal to the fourth threshold. The seventh signal indicates a short circuit between the second terminal of the interface selection module and the first terminal of the drive module.

8. The detection circuit according to any one of claims 5 to 7, characterized in that, The second switch is turned on earlier than the third switch, and the third switch is turned on earlier than the fourth switch.

9. The detection circuit according to any one of claims 1 to 7, characterized in that, The i-th switching unit includes at least one of the following: an occupant airbag disable switch, a driver seatbelt buckle circuit switch, and a rollover airbag disable switch.

10. A detection method, characterized in that, The detection method is used in the detection circuit according to any one of claims 1 to 9; The method includes: The control module in the detection circuit is used to control the second switch in the voltage interface unit of the first interface unit connected to the first switch unit to be in the on state, the third switch in the current interface unit of the first interface unit connected to the first switch unit to be in the off state, and the fourth switch in the first drive unit connected to the first switch unit to be in the off state. The detection module is used to detect that the first voltage corresponding to the first switch in the first switching unit is greater than the voltage threshold, and outputs a first signal, wherein the first signal indicates that there is a short circuit between at least one switching unit and the power supply in the switch to be detected.

11. The detection method according to claim 10, characterized in that, include: The control module is used to control the second switch and the third switch to be in the on state, and to control the fourth switch to be in the off state; The detection module is used to detect that the first current corresponding to the first switch is greater than the current threshold and output a second signal, wherein the second signal indicates that there is a short circuit between at least one switch unit and ground in the switch to be detected.

12. The detection method according to claim 10, characterized in that, include: When the first voltage is less than or equal to a voltage threshold and the first current is less than or equal to a current threshold, the control module controls the second switch, the third switch, and the fourth switch to be in the ON state. The detection module is used to detect the second voltage and the second current corresponding to the first switch; When the ratio of the second voltage to the second current is greater than the first threshold, a third signal is output, which indicates that there is an open circuit between the second terminal of the interface selection module and the first terminal of the drive module. If the ratio of the second voltage to the second current is less than or equal to the first threshold and greater than the second threshold, a fourth signal is output, which indicates that the first switch is open. If the ratio of the second voltage to the second current is less than or equal to the second threshold and greater than the third threshold, a fifth signal is output, which indicates that the second voltage and the second current are invalid. If the ratio of the second voltage to the second current is less than or equal to the third threshold and greater than the fourth threshold, a sixth signal is output, which indicates that the first switch is closed. When the ratio of the second voltage to the second current is less than or equal to the fourth threshold, a seventh signal is output, which indicates a short circuit between the second terminal of the interface selection module and the first terminal of the drive module.

13. An airbag controller, characterized in that, The detection circuit includes any one of claims 1 to 9.

14. A vehicle-mounted device, characterized in that, Includes the airbag controller as described in claim 13.

15. A vehicle, characterized in that, Includes the vehicle-mounted equipment as described in claim 14.

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