Switch circuit, battery management system and vehicle

Abstract

Embodiments of the present application provide a switch circuit, a battery management system and a vehicle. The switch circuit comprises a switch module, wherein the switch module is suitable for being connected to a battery and a power management chip; when a signal input by the switch module is a turn-off signal, the switch module is turned off to disconnect a positive electrode of the battery from a power end of the power management chip; and when a signal input by the switch module is a turn-on signal, the switch module is turned on to enable the battery to supply power to the power end of the power management chip. The embodiments of the present application can reduce the quiescent current of the power management chip.

Description

Switching circuits, battery management systems, and vehicles

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202421754764.5, filed on July 22, 2024, entitled "Switching Circuit, Battery Management System and Vehicle", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of electronic circuit technology, specifically to a switching circuit, a battery management system, and a vehicle. Background Technology

[0004] With the development of vehicle electrification, there are more and more electrical appliances in vehicles. However, due to limitations in size and materials, the total battery capacity is finite. Therefore, managing the battery consumption of appliances that remain connected after the vehicle is turned off is crucial. Otherwise, the vehicle may fail to start on the next attempt due to a depleted battery. Currently, power management chips still exhibit significant quiescent current. Summary of the Invention

[0005] This application provides a switching circuit, a battery management system, and a vehicle that can reduce the quiescent current of the power management chip.

[0006] A first aspect of this application provides a switching circuit, including a switching module, the switching module being adapted to connect a battery and a power management chip;

[0007] When the signal input to the switching module is a shutdown signal, the switching module is disconnected, thereby disconnecting the positive terminal of the battery from the power supply terminal of the power management chip.

[0008] When the signal input to the switch module is a conduction signal, the switch module is turned on, so that the battery supplies power to the power terminal of the power management chip.

[0009] In this embodiment, when the input signal to the switching module is a shutdown signal, the switching module is disconnected, thereby disconnecting the positive terminal of the battery from the power supply terminal of the power management chip, physically cutting off the battery from the power management chip, and thus reducing the static current of the power management chip.

[0010] Optionally, the input terminal of the switch module is adapted to connect to the output terminal of the output module; the output module is used to input the off signal or on signal to the input terminal of the switch module through the output terminal.

[0011] Optionally, the switching module includes at least one switching transistor.

[0012] Optionally, the switch module includes a first switch unit and a second switch unit, wherein the control terminal of the second switch unit is connected to the first terminal of the first switch unit.

[0013] Optionally, the first terminal of the second switching unit is connected to the positive terminal of the battery, the second terminal of the second switching unit is connected to the power terminal of the power management chip, the control terminal of the first switching unit is connected to the output terminal of the output module, and the second terminal of the first switching unit is grounded.

[0014] Optionally, the first switching unit includes a first semiconductor switch, a first end of which is connected to the control terminal of the second switching unit, and a second end of which is grounded.

[0015] Optionally, the first switching unit further includes a first resistor and a second resistor. The output terminal of the output module is 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 control terminal of the first semiconductor switch, and the second terminal of the second resistor is grounded.

[0016] Optionally, the first switching unit further includes a first diode, and the output terminal of the output module is connected to the first terminal of the first resistor through the first diode; the output terminal of the output module is connected to the positive terminal of the first diode, and the negative terminal of the first diode is connected to the first terminal of the first resistor.

[0017] Optionally, the second switching unit includes a second semiconductor switch, the positive terminal of the battery is connected to the first terminal of the second semiconductor switch, the second terminal of the second semiconductor switch is connected to the power supply terminal of the power management chip, and the control terminal of the second semiconductor switch is connected to the first terminal of the first semiconductor switch.

[0018] Optionally, the second switching unit further includes a third resistor, wherein the control terminal of the second semiconductor switch is connected to the first terminal of the first semiconductor switch through the third resistor, the control terminal of the second semiconductor switch is connected to the first terminal of the third resistor, and the second terminal of the third resistor is connected to the first terminal of the first semiconductor switch.

[0019] Optionally, the second switching unit further includes a second diode, the positive terminal of the battery is connected to the first terminal of the second semiconductor switch through the second diode, the positive terminal of the battery is connected to the positive terminal of the second diode, and the negative terminal of the second diode is connected to the first terminal of the second semiconductor switch.

[0020] Optionally, the wake-up terminal of the power management chip is connected to the output terminal of the output module or the negative terminal of the first diode. When the output terminal of the output module outputs a conduction signal, the power management chip is powered on.

[0021] Optionally, the power supply terminal of the power management chip is connected to the power supply terminal of the main control chip, and the wake-up terminal of the power management chip is connected to the first output terminal of the main control chip and the negative terminal of the first diode; the main control chip is a chip that controls the switching module and the power management chip.

[0022] When the power management chip is powered on, the main control chip is powered on;

[0023] When the main control chip is powered on, the first output terminal of the main control chip outputs a self-locking signal to keep the first semiconductor switch continuously on.

[0024] Optionally, the switching circuit further includes a fourth resistor and a third diode. The anode of the third diode is connected to the first output terminal of the main control chip, the cathode of the third diode is connected to the first terminal of the fourth resistor and the cathode of the first diode, and the second terminal of the fourth resistor is grounded.

[0025] Optionally, the switching circuit further includes a third switching unit, which includes a third semiconductor switch and an AND gate. The first terminal of the third semiconductor switch is connected to the positive terminal of the second diode, the second terminal of the third semiconductor switch is connected to the main circuit module, the control terminal of the third semiconductor switch is connected to the output terminal of the AND gate, the first input terminal of the AND gate is connected to the output terminal of the power management chip, and the second input terminal of the AND gate is connected to the second output terminal of the main control chip. The main circuit module is used to control the rotation of the motor.

[0026] Optionally, the semiconductor switch includes a transistor or a field-effect transistor.

[0027] A second aspect of this application provides a battery management system, including a power management chip and a switching circuit as described in any of the first aspects of this application.

[0028] A third aspect of this application provides a vehicle including a battery and a battery management system as described in any of the second aspects of this application. The battery management system may include an electric power steering (EPS) system, which is a power steering system that directly relies on an electric motor to provide auxiliary torque. EPS can determine the rotation direction of the electric motor and the magnitude of the assist current based on signals from a vehicle speed sensor and a torque sensor, thereby achieving real-time control of the power steering.

[0029] The switching circuit of this application embodiment includes a switching module adapted to connect a battery and a power management chip. When the signal input to the switching module is an off signal, the switching module is disconnected, thereby disconnecting the positive terminal of the battery from the power supply terminal of the power management chip. When the signal input to the switching module is an on signal, the switching module is turned on, allowing the battery to supply power to the power supply terminal of the power management chip. In this application embodiment, when the signal input to the switching module is an off signal, the switching module is disconnected, thereby physically cutting off the connection between the battery and the power management chip, thus reducing the quiescent current of the power management chip. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 is a schematic diagram of a switching circuit provided in an embodiment of this application;

[0032] Figure 2 is a schematic diagram of another switching circuit provided in an embodiment of this application;

[0033] Figure 3 is a schematic diagram of another switching circuit provided in an embodiment of this application;

[0034] Figure 4 is a schematic diagram of another switching circuit provided in an embodiment of this application;

[0035] Figure 5 is a schematic diagram of another switching circuit provided in an embodiment of this application;

[0036] Figure 6 is a schematic diagram of another switching circuit provided in an embodiment of this application;

[0037] Figure 7 is a schematic diagram of another switching circuit provided in an embodiment of this application;

[0038] Figure 8 is a circuit diagram showing that the output terminal KL15 of an ignition system is directly connected to the wake-up terminal WAK of a power management chip according to an embodiment of this application.

[0039] Figure 9 is a schematic block diagram of a battery management system provided in an embodiment of this application;

[0040] Figure 10 is a schematic block diagram of a vehicle provided in an embodiment of this application.

[0041] Reference numerals: 100 - Switching circuit; 10 - Switching module; 10a - Input terminal of the switching module; 101 - First switching unit; 101a - First terminal of the first switching unit; 101b - Control terminal of the first switching unit; 101c - Second terminal of the first switching unit; Q1 - First semiconductor switch; Q10a - First terminal of the first semiconductor switch; Q10b - Second terminal of the first semiconductor switch; Q10c - Control terminal of the first semiconductor switch; R1 - First resistor; R10a - First terminal of the first resistor; R10b - Second terminal of the first resistor; R2 - Second resistor; R20a - First terminal of the second resistor; R20b - Second terminal of the second resistor; D1 - First diode; D10a - First diode... Positive terminal; D10b - Negative terminal of the first diode; 102 - Second switching unit; 102a - First terminal of the second switching unit; 102b - Second terminal of the second switching unit; 102c - Control terminal of the second switching unit; Q2 - Second semiconductor switch; Q20a - First terminal of the second semiconductor switch; Q20b - Second terminal of the second semiconductor switch; Q20c - Control terminal of the second semiconductor switch; R3 - Third resistor; R30a - First terminal of the third resistor; R30b - Second terminal of the third resistor; D2 - Second diode; D20a - Positive terminal of the second diode; D20b - Cathode of the second diode; 20 - Output module; KL15 - Output terminal of the output module; R4 - Fourth resistor; R40a - First terminal of the fourth resistor; R40b - Second terminal of the fourth resistor; D3 - Third diode; D30a - Anode of the third diode; D30b - Cathode of the third diode; 30 - Third switching unit; Q3 - Third semiconductor switch; Q30a - First terminal of the third semiconductor switch; Q30b - Second terminal of the third semiconductor switch; Q30c - Control terminal of the third semiconductor switch; U1 - AND gate; U10a - Output of the AND gate Terminals: U10b - First input of AND gate; U10c - Second input of AND gate; 2 - Battery; KL30 - Positive terminal of battery; 3 - Power management chip; VS - Power supply terminal of power management chip; WAK - Wake-up terminal of power management chip; QXX - Power supply terminal of power management chip; SS1 - Output terminal of power management chip; 4 - Main control chip; 40a - Power supply terminal of main control chip; IO-LOCK - First output terminal of main control chip; IO-CTRL - Second output terminal of main control chip; 5 - Main circuit module; 200 - Battery management system; 300 - Vehicle. Detailed Implementation

[0042] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0043] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0044] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0045] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0046] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0047] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, system, product, or apparatus that comprises a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, products, or apparatuses.

[0049] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0050] With the development of vehicle electrification, the number of electrical appliances in vehicles is increasing. However, due to limitations in size and materials, the total battery capacity is finite. Therefore, managing the battery consumption of appliances still connected after the vehicle is turned off is crucial. Otherwise, the vehicle may fail to start on the next attempt due to a depleted battery. Currently, power management chips draw power directly from the battery. Even after the vehicle is turned off, the power is not physically cut off. While the power management chip controls itself to enter a sleep or low-power mode to reduce power consumption, it still retains a significant static current.

[0051] Please refer to Figure 1, which is a schematic diagram of a switching circuit 100 provided in an embodiment of this application. As shown in Figure 1, the switching circuit 100 may include a switching module 10, which is adapted to connect a battery 2 and a power management chip 3. When the signal input to the switching module 10 is an off signal, the switching module 10 is disconnected, so that the positive terminal KL30 of the battery 2 is disconnected from the power supply terminal VS of the power management chip 3. When the signal input to the switching module 10 is an on signal, the switching module 10 is turned on, so that the battery 2 supplies power to the power supply terminal VS of the power management chip 3.

[0052] In this embodiment, battery 2 can be a storage battery 2 on vehicle 300. For example, it can be a 12V storage battery 2, which can provide 12V DC power.

[0053] When the switch module 10 is off, the power management chip 3 is powered down; when the switch module 10 is on, the power management chip 3 is powered on.

[0054] After power-on, the power management chip 3 is used to supply power to the various modules on the vehicle 300.

[0055] After power is off, the power management chip 3 physically disconnects the battery 2 from the power management chip 3 because the switching module 10 is disconnected, thereby reducing the static current of the power management chip 3.

[0056] In this embodiment, when the signal input to the switch module 10 is a turn-off signal, the switch module 10 is turned off, so that the positive terminal KL30 of the battery 2 is disconnected from the power terminal VS of the power management chip 3, thereby physically disconnecting the battery 2 from the power management chip 3 and reducing the static current of the power management chip 3.

[0057] Please refer to Figure 2, which is a schematic diagram of another switching circuit 100 provided in an embodiment of this application. Figure 2 is based on Figure 1. As shown in Figure 2, the input terminal 10a of the switching module 10 is adapted to connect to the output terminal KL15 of the output module 20; the output module 20 is used to input the off signal or the on signal to the input terminal 10a of the switching module 10 through the output terminal.

[0058] The output module 20 is used to control the switch module 10 to open or close. The output module 20 can be the ignition system of the vehicle 300. When the ignition system is off, the output module 20 can output a shutdown signal (e.g., an ignition shutdown signal), and when the ignition system is on, the output module 20 can output an on signal (e.g., an ignition signal).

[0059] The switching module 10 includes at least one switching transistor. The switching transistor can be a semiconductor switch.

[0060] Please refer to Figure 3, which is a schematic diagram of another switching circuit 100 provided in an embodiment of this application. Figure 3 is based on Figure 2. As shown in Figure 3, the switching module 10 includes a first switching unit 101 and a second switching unit 102. The control terminal 102c of the second switching unit 102 is connected to the first terminal 101a of the first switching unit 101.

[0061] Optionally, as shown in Figure 3, the output terminal KL15 (output terminal of the ignition system) of the output module 20 is connected to the control terminal 101b of the first switch unit 101, the first terminal 102a of the second switch unit 102 is connected to the positive terminal KL30 of the battery 2, and the second terminal 102b of the second switch unit 102 is connected to the power terminal VS of the power management chip 3.

[0062] When the output terminal KL15 of the output module 20 outputs a conduction signal (for example, the output terminal KL15 of the ignition system outputs an ignition stop signal), the first switch unit 101 is turned off, so that the second switch unit 102 is turned off, so that the positive terminal KL30 of the battery 2 is disconnected from the power terminal VS of the power management chip 3, and the power management chip 3 is powered down.

[0063] In this embodiment, the flameout signal can be a signal that triggers the first switching unit 101 to open. When the first switching unit 101 is open, the control terminal 102c of the second switching unit 102 is disconnected from ground, and thus the second switching unit 102 is open. Specifically, the first switching unit 101 is turned on when its control terminal 101b receives a high-level signal, and turned off when its control terminal 101b receives a low-level signal; the second switching unit 102 is open when the first switching unit 101 is open, and turned on when the first switching unit 101 is turned on.

[0064] For example, the engine shutdown signal is a low-level signal. When a low-level signal is input to the control terminal 101b of the first switching unit 101, the first switching unit 101 is disconnected, and since there is no signal input to the control terminal 102c of the second switching unit 102, the second switching unit 102 is also disconnected. When the second switching unit 102 is disconnected, the power terminal VS of the power management chip 3 is disconnected from the positive terminal KL30 of the battery 2, and the power management chip 3 loses power supply, causing the power management chip 3 to power down.

[0065] In Figure 3, the negative terminal of battery 2 is grounded.

[0066] In this embodiment, after the vehicle 300 is turned off, the output terminal KL15 of the output module 20 outputs a shutdown signal (e.g., an engine shutdown signal), the first switching unit 101 is disconnected, causing the second switching unit 102 to disconnect, and the power management chip 3 is powered down. After the vehicle 300 is turned off, the second switching unit 102 disconnects the positive terminal KL30 of the battery 2 from the power terminal VS of the power management chip 3, thereby reducing the quiescent current of the power management chip 3 after the vehicle 300 is turned off.

[0067] Battery 2 can be the storage battery 2 on vehicle 300. For example, it can be a 12V storage battery 2, which can provide 12V DC power.

[0068] Optionally, when the output terminal KL15 of the output module 20 outputs a conduction signal (e.g., an ignition signal), the first switching unit 101 is turned on, so that the second switching unit 102 is turned on, so that the battery 2 supplies power to the power terminal VS of the power management chip 3, and the power management chip 3 is powered on at this time.

[0069] For example, the ignition signal is a high-level signal. When a high-level signal is input to the control terminal 101b of the first switching unit 101, the first switching unit 101 is turned on, and the control terminal 102c of the second switching unit 102 is essentially grounded (i.e., a low-level signal is input to the control terminal 102c of the second switching unit 102), and the second switching unit 102 is turned on. When the second switching unit 102 is turned on, the power terminal VS of the power management chip 3 is connected to the positive terminal KL30 of the battery 2, and the power management chip 3 is powered.

[0070] In this embodiment of the application, after the vehicle 300 is ignited, the output terminal KL15 of the ignition system outputs an ignition signal, the first switching unit 101 is turned on, so that the second switching unit 102 is turned on, and the power management chip 3 is powered.

[0071] Please refer to Figure 4, which is a schematic diagram of another switching circuit 100 provided in an embodiment of this application. Figure 4 is derived from Figure 3. As shown in Figure 4, the first switching unit 101 includes a first semiconductor switch Q1. The first terminal Q10a of the first semiconductor switch Q1 is connected to the control terminal 102c of the second switching unit 102, and the second terminal Q10b of the first semiconductor switch Q1 is grounded.

[0072] Optionally, as shown in Figure 4, the first switching unit 101 further includes a first resistor R1 and a second resistor R2. The output terminal KL15 of the output module 20 is connected to the first terminal R10a of the first resistor R1. The second terminal R10b of the first resistor R1 is connected to the first terminal R20a of the second resistor R2 and the control terminal Q10c of the first semiconductor switch Q1. The second terminal R20b of the second resistor R2 is grounded.

[0073] Optionally, the first switching unit 101 further includes a first diode D1, and the output terminal KL15 of the output module 20 is connected to the first terminal R10a of the first resistor R1 through the first diode D1; the output terminal KL15 of the output module 20 is connected to the positive terminal D10a of the first diode D1, and the negative terminal D10b of the first diode D1 is connected to the first terminal R10a of the first resistor R1.

[0074] In this circuit, the first resistor R1 and the second resistor R2 form a voltage divider circuit. The resistance values ​​of the first resistor R1 and the second resistor R2 can be set according to the forward voltage of the first diode D1 and the high-level voltage. Taking the ignition system as an example, the first diode D1 in the output module 20 is a reverse protection diode, which allows the signal output from the ignition system to reach the control terminal Q10c of the first semiconductor switch Q1 through the first diode D1, preventing the signal from the control terminal Q10c of the first semiconductor switch Q1 from flowing back to the output terminal of the ignition system and preventing interference with the signal at the output terminal of the ignition system.

[0075] Optionally, as shown in Figure 4, the second switching unit 102 includes a second semiconductor switch Q2. The positive terminal KL30 of the battery 2 is connected to the first terminal Q20a of the second semiconductor switch Q2, the second terminal Q20b of the second semiconductor switch Q2 is connected to the power terminal VS of the power management chip 3, and the control terminal Q20c of the second semiconductor switch Q2 is connected to the first terminal Q10a of the first semiconductor switch Q1.

[0076] Optionally, as shown in Figure 4, the second switching unit 102 further includes a third resistor R3. The control terminal Q20c of the second semiconductor switch Q2 is connected to the first terminal Q10a of the first semiconductor switch Q1 through the third resistor R3. The control terminal Q20c of the second semiconductor switch Q2 is connected to the first terminal R30a of the third resistor R3. The second terminal R30b of the third resistor R3 is connected to the first terminal Q10a of the first semiconductor switch Q1.

[0077] Optionally, as shown in Figure 4, the second switching unit 102 further includes a second diode D2. The positive terminal KL30 of the battery 2 is connected to the first terminal Q20a of the second semiconductor switch Q2 through the second diode D2. The positive terminal KL30 of the battery 2 is connected to the positive terminal D20a of the second diode D2, and the negative terminal D20b of the second diode D2 is connected to the first terminal Q20a of the second semiconductor switch Q2.

[0078] Among them, the second diode D2 is a reverse protection diode to prevent the voltage of the power supply terminal VS of the power management chip 3 from flowing back to the positive terminal KL30 of the battery 2, thus preventing damage to the battery 2.

[0079] In Figure 4, the first semiconductor switch Q1 and the second semiconductor switch Q2 are examples of transistors. Specifically, the first semiconductor switch Q1 is an NPN transistor, and the second semiconductor switch is a PNP transistor.

[0080] Please refer to Figure 5, which is a schematic diagram of another switching circuit 100 provided in an embodiment of this application. Figure 5 is based on Figure 4. The wake-up terminal WAK of the power management chip 3 is connected to the output terminal KL15 of the output module 20 or the negative terminal D10b of the first diode D1. When the output terminal KL15 of the output module 20 outputs a conduction signal (e.g., an ignition signal), the power management chip 3 is powered on.

[0081] Taking the ignition system as an example, when the output module 20 outputs the ignition signal, the wake-up terminal WAK of the power management chip 3 is woken up, and the power terminal VS of the power management chip 3 is connected to the positive terminal KL30 of the battery 2, so that the power management chip 3 is powered.

[0082] In Figures 4 and 5, the power management chip 3 is powered on when the power supply terminal of the power management chip 3 is connected to the positive terminal KL30 of the battery 2 and the wake-up terminal WAK of the power management chip 3 is woken up.

[0083] After the power management chip 3 is powered on, it can output signals through the output terminal and also output voltage through the power supply terminal to supply power to other modules.

[0084] Optionally, as shown in Figure 5, the power supply terminal QXX of the power management chip 3 is connected to the power supply terminal 40a of the main control chip 4, and the wake-up terminal WAK of the power management chip 3 is connected to the first output terminal IO-LOCK of the main control chip 4 (as shown in Figure 3) and the negative terminal D10b of the first diode D1; the main control chip 4 is a chip that controls the switching module 10 and the power management chip 3.

[0085] When the power management chip 3 is powered on, the main control chip 4 is powered on;

[0086] When the power management chip 3 is powered on, the power supply terminal of the power management chip 3 can output voltage to the power supply terminal 40a of the main control chip 4, thereby powering on the main control chip 4.

[0087] When the main control chip 4 is powered on, the first output terminal IO-LOCK of the main control chip 4 outputs a self-locking signal IO-LOCK to keep the first semiconductor switch Q1 continuously on.

[0088] In this embodiment, the output terminal of the ignition system is connected to the positive terminal D10a of the first diode D1 via a snap-fit ​​connector. The vehicle 300 experiences bumps during operation. If the snap-fit ​​becomes loose, the output terminal of the ignition system will disconnect from the positive terminal D10a of the first diode D1, causing the power management chip 3 to enter sleep mode and malfunction. To avoid this, when the main control chip 4 is powered on, its first output terminal IO-LOCK outputs a self-locking signal IO-LOCK to keep the first semiconductor switch Q1 continuously conducting. This prevents the ignition signal from being lost due to jitter during vehicle operation and prevents abnormal power loss.

[0089] The self-locking signal can be a high-level signal. As long as the main control chip 4 is powered on, even if the ignition signal output from the ignition system is lost due to jitter, the power management chip 3 and the main control chip 4 will not experience abnormal power loss.

[0090] It should be noted that when the main control chip 4 outputs a shutdown signal at its first output terminal IO-LOCK, this shutdown signal will also pull the self-locking signal low, thereby causing the power management chip 3 to enter a sleep state.

[0091] The main control chip 4 can be a microcontroller unit (MCU).

[0092] Optionally, as shown in Figure 5, the switching circuit 100 further includes a fourth resistor R4 and a third diode D3. The negative terminal D30bD30a of the third diode D3 is connected to the first output terminal IO-LOCK of the main control chip 4. The negative terminal of the third diode D3 is connected to the second terminal R40bR40a of the fourth resistor R4 and the negative terminal D10b of the first diode D1. The second terminal of the fourth resistor R4 is grounded.

[0093] The first output terminal IO-LOCK of the main control chip 4 outputs a latching signal IO-LOCK to the negative terminal D30b / D30a of the third diode D3. Even if the ignition signal output from the ignition system is lost due to jitter, the first semiconductor switch Q1 can remain on by outputting the latching signal IO-LOCK from the first output terminal IO-LOCK of the main control chip 4. This prevents the ignition signal output from the ignition system from being lost due to jitter during vehicle operation, thus preventing abnormal power loss.

[0094] Please refer to Figure 6, which is a schematic diagram of another switching circuit 100 provided in this application embodiment. Figure 6 is based on Figure 5. The switching circuit 100 further includes a third switching unit, which includes a third semiconductor switch Q3 and an AND gate U1. The second terminals Q30b and Q30a of the third semiconductor switch Q3 are connected to the positive terminal D20a of the second diode D2. The second terminal of the third semiconductor switch Q3 is connected to the main circuit module 5. The control terminal Q30c of the third semiconductor switch Q3 is connected to the output terminal U10a of the AND gate U1. The first input terminal U10b of the AND gate U1 is connected to the output terminal SS1 of the power management chip 3. The second input terminal U10c of the AND gate U1 is connected to the second output terminal IO-CTRL of the main control chip 4. The main circuit module 5 is used to control the rotation of the motor.

[0095] In this embodiment, IO-CTRL and SS1 are control signals output by the main control chip 4 and the power management chip 3, respectively, to control the third semiconductor switch Q3. When both the output terminal SS1 of the power management chip 3 and the second output terminal IO-CTRL of the main control chip 4 output a high level, the main circuit module 5 is powered on and begins to work.

[0096] The main circuit module 5 can be a component of the battery management system 200, and the main circuit module 5 can be used to control the rotation of the motor.

[0097] Optionally, the semiconductor switch includes a transistor or a field-effect transistor.

[0098] In Figures 4 to 6 above, the first semiconductor switch Q1 and the second semiconductor switch Q2 are both transistors, and the third semiconductor switch Q3 is a field-effect transistor.

[0099] Please refer to Figure 7, which is a schematic diagram of another switching circuit 100 provided in an embodiment of this application. Compared with Figure 6, the first semiconductor switch Q1 and the second semiconductor switch Q2 in Figure 7 are replaced with field-effect transistors (FETs). FETs can include metal-oxide-semiconductor field-effect transistors (MOSFETs), which can also be simply referred to as MOS transistors. MOS transistors can include N-channel MOS transistors (NMOS) or P-channel MOS transistors (PMOS). For example, the first semiconductor switch Q1 in Figure 7 is an NMOS, the second semiconductor switch Q2 is a PMOS, and the third semiconductor switch Q3 is an NMOS.

[0100] Please refer to Figure 8, which is a circuit diagram showing the direct connection between the output terminal KL15 of the output module 20 and the wake-up terminal WAK of the power management chip 3 according to an embodiment of this application. In Figure 8, the positive terminal KL30 of the battery 2 is connected to the power terminal VS of the power management chip 3 through the second diode D2. When the power management chip 3 is in sleep mode, the positive terminal KL30 of the battery 2 is connected to the power terminal VS of the power management chip 3 through the second diode D2, and the power management chip 3 generates a certain static current, approximately 70 microamps (µA). When the vehicle is turned off, compared with the circuit scheme in Figure 8, the static current in Figure 6 changes from the operating current of the power management chip 3 in sleep mode to the leakage current of the second semiconductor switch Q2, which is approximately 0.1µA. The static current changes from 70µA to 0.1µA (0.1µA is the leakage current of the second semiconductor switch Q2), greatly reducing the static current of the power management chip 3. This minimizes the power consumption of the power management chip 3 in the vehicle's power-off state, almost eliminating the power consumption of the vehicle.

[0101] As shown in Figure 6, in this embodiment of the application, a switching circuit 100 is added to the front end of the power management chip 3, and the ignition signal is used as the input of this switching circuit 100. In this way, the static current of the entire electric power steering system EPS is transformed from the static current of the power management chip 3 in Figure 8 to the leakage current of the second semiconductor switch Q2 of the switching circuit 100 in Figure 6, which greatly reduces the static current of the system. In the off state, the power management chip 3 consumes the least amount of power to the vehicle (battery 2), and almost no power to the vehicle is consumed.

[0102] After the electric power steering system EPS is powered on, the main control chip 4 uses the self-locking signal output from the first output port to form a self-locking of the ignition signal, ensuring that the ignition signal will not be lost due to vibration during vehicle 300 driving, which would cause the system to lose power abnormally.

[0103] When the vehicle 300 is turned off, since there is no self-locking signal, the power management chip 3 and the vehicle power supply are disconnected, and the main circuit is also disconnected through the third semiconductor switch Q3. At this time, the static current of the electric power steering system EPS is almost zero, which minimizes the static current of the electric power steering system EPS.

[0104] When the vehicle 300 is ignited, the output terminal KL15 of the output module 20 outputs a conduction signal (e.g., an ignition signal). The output terminal of the ignition signal outputs a high-level signal. The first semiconductor switch Q1 is turned on through the switch control circuit composed of the ignition signal, the first resistor R1, and the second resistor R2. The second semiconductor switch Q2 is turned on through the first semiconductor switch Q1 and the third resistor R3. At this time, the power terminal VS of the power management chip 3 is energized and outputs QXX power to supply power to the modules of the system. The first output terminal IO-LOCK of the main control chip 4 outputs a self-locking signal to keep the first semiconductor switch Q1 on, preventing the ignition signal from being lost due to jitter during the driving of the vehicle 300, which would cause the system to lose power abnormally.

[0105] This application also provides a battery management system 200. Referring to FIG9, it includes any one of the switching circuits 100 in FIG1 to FIG7. The battery management system 200 may further include a power management chip 3, a control chip, and a main circuit module 5. The battery management system 200 may be an electric power steering system (EPS).

[0106] This application also provides a vehicle 300, as shown in FIG10, which includes the battery management system 200 described above.

[0107] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0108] In the several embodiments provided in this application, it should be understood that the disclosed switch circuit 100, battery management system 200, and vehicle 300 can be implemented in other ways. For example, the switch circuit 100 embodiment described above is merely illustrative. For instance, the division of the units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

Claims

1. A switching circuit, wherein, The switch module (10) is adapted to connect the battery (2) and the power management chip (3); In the case that the signal input into the switch module (10) is an off signal, the switch module (10) is turned off to disconnect the positive pole (KL30) of the battery (2) from the power terminal (VS) of the power management chip (3); In the case that the signal input into the switch module (10) is an on signal, the switch module (10) is turned on to supply power from the battery (2) to the power terminal (VS) of the power management chip (3).

2. The switching circuit of claim 1, wherein, The input end (10a) of the switch module (10) is adapted to connect the output end (KL15) of the output module (20); the output module (20) is used to input the off signal or on signal into the input end (10a) of the switch module (10) through the output end.

3. The switching circuit according to claim 1 or 2, wherein The switch module (10) comprises at least one switch tube.

4. The switching circuit of claim 2, wherein, The switch module (10) comprises a first switch unit (101) and a second switch unit (102), and a control end (102c) of the second switch unit (102) is connected to a first end (101a) of the first switch unit (101).

5. The switching circuit of claim 4, wherein, A first end (102a) of the second switch unit (102) is connected to the positive pole (KL30) of the battery (2), a second end (102b) of the second switch unit (102) is connected to the power terminal (VS) of the power management chip (3), a control end (101b) of the first switch unit (101) is connected to the output end (KL15) of the output module (20), and a second end (101c) of the first switch unit (101) is grounded.

6. The switching circuit of claim 5, wherein, The first switch unit (101) comprises a first semiconductor switch (Q1), a first end (Q10a) of the first semiconductor switch (Q1) is connected to the control end (102c) of the second switch unit (102), and a second end (Q10b) of the first semiconductor switch (Q1) is grounded.

7. The switching circuit of claim 6, wherein, The first switch unit (101) further comprises a first resistor (R1) and a second resistor (R2), an output end (200) of the output module (20) is connected to a first end (R10a) of the first resistor (R1), a second end (R10b) of the first resistor (R1) is connected to a first end (R20a) of the second resistor (R2) and a control end (Q10c) of the first semiconductor switch (Q1), and a second end (R20b) of the second resistor (R2) is grounded.

8. The switching circuit of claim 7, wherein, The first switch unit (101) further comprises a first diode (D1), the output end (KL15) of the output module (20) is connected to the first end (R10a) of the first resistor (R1) through the first diode (D1), the output end (KL15) of the output module (20) is connected to the positive pole (D10a) of the first diode (D1), and the negative pole (D10b) of the first diode (D1) is connected to the first end (R10a) of the first resistor (R1).

9. The switching circuit of claim 8, wherein, The second switch unit (102) comprises a second semiconductor switch (Q2), a positive electrode (KL30) of the battery (2) is connected to a first end (Q20a) of the second semiconductor switch (Q2), a second end (Q20b) of the second semiconductor switch (Q2) is connected to a power supply end (VS) of the power management chip (3), and a control end (Q20c) of the second semiconductor switch (Q2) is connected to a first end (Q10a) of the first semiconductor switch (Q1).

10. The switching circuit of claim 9, wherein, The second switch unit (102) further comprises a third resistor (R3), the control end (Q20c) of the second semiconductor switch (Q2) is connected to the first end (Q10a) of the first semiconductor switch (Q1) through the third resistor (R3), the control end (Q20c) of the second semiconductor switch (Q2) is connected to a first end (R30a) of the third resistor (R3), and a second end (R30b) of the third resistor (R3) is connected to the first end (Q10a) of the first semiconductor switch (Q1).

11. The switching circuit of claim 9 or 10, wherein, The second switch unit (102) further comprises a second diode (D2), the positive electrode (KL30) of the battery (2) is connected to the first end (Q20a) of the second semiconductor switch (Q2) through the second diode (D2), the positive electrode (2) of the battery (2) is connected to a positive electrode (D20a) of the second diode (D2), and a negative electrode (D20b) of the second diode (D2) is connected to the first end (Q20a) of the second semiconductor switch (Q2).

12. The switching circuit of claim 9, wherein, The wake-up end (WAK) of the power management chip (3) is connected to an output end (KL15) of the output module (20) or a negative electrode (D10b) of the first diode (D1), and the power management chip (3) is powered on in the case that the output end (KL15) of the output module (20) outputs a conduction signal.

13. The switching circuit of claim 12, wherein, The power supply end (QXX) of the power management chip (3) is connected to a power supply end (40a) of a master control chip (4), the wake-up end (WAK) of the power management chip (3) is connected to a first output end (IO-LOCK) of the master control chip (4) and the negative electrode (D10b) of the first diode (D1), and the master control chip (4) is a chip for controlling the switch module (10) and the power management chip (3). The master control chip (4) is powered on in the case that the power management chip (3) is powered on. In the case that the master control chip (4) is powered on, the first output end (IO-LOCK) of the master control chip (4) outputs a self-locking signal to make the first semiconductor switch (Q1) continuously conductive.

14. The switching circuit of claim 13, wherein, The switch circuit (100) further comprises a fourth resistor (R4) and a third diode (D3), a positive electrode (D30a) of the third diode (D3) is connected to a first output end (IO-LOCK) of the master control chip (4), a negative electrode (D30b) of the third diode (D3) is connected to a first end (R40a) of the fourth resistor (R4) and a negative electrode (D10b) of the first diode (D1), and a second end (R40b) of the fourth resistor (R4) is grounded.

15. The switching circuit of claim 14, wherein, The switch circuit (100) further comprises a third switch unit (30), the third switch unit (30) comprises a third semiconductor switch (Q3) and an AND gate (U1), a first end (Q30a) of the third semiconductor switch (Q3) is connected to a positive electrode (D20a) of the second diode (D2), a second end (Q30b) of the third semiconductor switch (Q3) is connected to a main circuit module (5), a control end (Q30c) of the third semiconductor switch (Q3) is connected to an output end (U10a) of the AND gate (U1), a first input end (U10b) of the AND gate (U1) is connected to an output end (SS1) of the power management chip (3), and a second input end (U10c) of the AND gate (U1) is connected to a second output end (IO-CTRL) of the master control chip (4); the main circuit module (5) is used for controlling rotation of a motor.

16. The switching circuit according to any one of claims 6 to 10, 12 to 15, wherein The semiconductor switch comprises a triode or a field effect transistor.

17. A battery management system, wherein, The battery management system (200) comprises the power management chip (3) and the switch circuit (100) according to any one of claims 1-16.

18. A vehicle, wherein, The battery management system (200) comprises the battery (2) and the switch circuit (100) according to claim 17.

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