Vehicle and current monitoring device and method for anti-reverse circuit
By using a current monitoring device with an anti-reverse circuit, and by calculating the current using a temperature acquisition component and a voltage detection module, the problems of large detection error of dormant current and high cost of sampling resistor in centralized vehicle electrical architecture are solved, and accurate monitoring of dormant current and operating current is achieved.
Patent Information
- Application Number
- CN202511804664.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-02
- Publication Date
- 2026-03-03
AI Technical Summary
In centralized vehicle electronic and electrical architectures, the dormant current detection of low-voltage batteries has large errors and the sampling resistors are expensive, making it impossible to accurately monitor the current.
The current monitoring device employing the anti-reverse circuit includes an anti-reverse switch, a temperature acquisition component, a voltage detection module, and an amplification component. The control component calculates the current based on the type of anti-reverse switch and the vehicle status, combined with the temperature and voltage values.
It enables accurate monitoring of the sleep current and operating current of the area controller, reduces the cost of sampling resistors, and improves detection accuracy.
Smart Images
Figure CN121595947A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of vehicle technology, and more particularly to a current monitoring device and method for a vehicle and an anti-reverse circuit. Background Technology
[0002] With the development of vehicle electronic and electrical architecture, centralized architecture has become the mainstream choice for automakers. Conventional intelligent power distribution boxes are gradually being replaced by regional controller power distribution, which is the core feature of the new generation architecture.
[0003] The core of power distribution is power allocation, which is mainly achieved through fuses in distributed architectures; centralized architectures rely on electronic fuses and high-side drivers (HSDs). Current centralized architectures monitor low-voltage batteries primarily focusing on dormant current, which is collected by sampling the voltage across a resistor.
[0004] However, in related technologies, the operating current of low-voltage batteries needs to be calculated by adding the currents of each distribution branch, which makes it impossible to detect the dormant current accurately. Furthermore, as the number of electronic components in the vehicle increases, the error in current detection will be greater, and the cost of sampling resistors is also high, which urgently needs to be addressed. Summary of the Invention
[0005] This application provides a current monitoring device and method for a vehicle, a vehicle, and an anti-reverse circuit, aiming to improve the problems of large errors and high cost of sampling resistors in related technologies. It achieves simultaneous monitoring of the sleep current and operating current of the area controller through a simple circuit, making it simple to implement.
[0006] To achieve the above objectives, the first aspect of this application provides a current monitoring device for an anti-reverse circuit, comprising: an anti-reverse switch, a temperature acquisition component, a voltage detection module, an amplification component, and a control component.
[0007] Anti-reverse switch and temperature acquisition component for acquiring the current temperature of the anti-reverse circuit; A voltage detection module, comprising a first voltage detection unit and / or a second voltage detection unit, wherein one end of the first voltage detection unit is connected to a first detection point, and one end of the second voltage detection unit is connected to a second detection point; An amplification component, comprising a first amplification unit and / or a second amplification unit, wherein the non-inverting input terminal and the inverting input terminal of the first amplification unit are respectively connected to the two ends of the anti-reverse switch, and the non-inverting input terminal and the inverting input terminal of the second amplification unit are respectively connected to the two ends of the anti-reverse switch. A control component is connected to the temperature acquisition component, the other end of the first voltage detection unit, the other end of the second voltage detection unit, the output terminal of the first amplification unit, and the output terminal of the second amplification unit. The control component is configured to obtain the operating current or sleep current of the anti-reverse switch based on the type and current state of the anti-reverse switch, according to at least one of the detection values of the first voltage detection unit, the detection values of the second voltage detection unit, the output voltage of the first amplification unit, and the first output voltage of the second amplification unit.
[0008] Therefore, the current temperature of the anti-reverse circuit is collected, and the voltage value of the anti-reverse switch detection point in the anti-reverse circuit is determined according to the type of the anti-reverse switch and the current state of the vehicle. The non-inverting and inverting input terminals of the first amplification unit and / or the second amplification unit are respectively connected to the two ends of the anti-reverse switch. Based on the type of the anti-reverse switch and the current state, the control component obtains the operating current or sleep current of the anti-reverse circuit according to the current temperature, the voltage value of the anti-reverse switch detection point, and the output voltage of the first and second amplification units. This solves the problems of large error and high cost of sampling resistors in related technologies, and simultaneously monitors the sleep current and operating current of the area controller through a simple circuit, making it simple to implement.
[0009] According to one embodiment of this application, the first voltage detection unit includes: a first switching circuit and a first voltage divider circuit, wherein, The input terminal of the first switching circuit is connected to the first detection point, the output terminal of the first switching circuit is connected to the first voltage divider circuit, the control terminal of the first switching circuit is connected to the first output terminal of the control component, and the first switching circuit is configured to be in a closed state when a first closing signal is received. The first detection point is the connection node between the anti-reverse switch and the vehicle battery. The first voltage divider circuit includes a first resistor, a second resistor, and a third resistor. One end of the first resistor is connected to the output terminal of the first switching circuit. One end of the second resistor is connected to the other end of the first resistor. The other end of the second resistor is connected to a grounding node. One end of the third resistor is connected to the connection node between the first resistor and the second resistor. The other end of the third resistor is connected to the first input terminal of the control component.
[0010] Therefore, by linking the first switching circuit with the first detection point and the control component, and by having the first voltage divider circuit composed of the first to third resistors connected to the control component, the target node voltage can be collected in a controlled and accurate manner, providing a stable and reliable voltage basis for the calculation of the anti-reverse circuit current.
[0011] According to one embodiment of this application, the second voltage detection unit includes: a second switching circuit and a second voltage divider circuit, wherein... The input terminal of the second switching circuit is connected to the second detection point, the output terminal of the second switching circuit is connected to the second voltage divider circuit, the control terminal of the second switching circuit is connected to the second output terminal of the control component, and the second switching circuit is configured to be in a closed state when a second closing signal is received. The second detection point is the connection node between the anti-reverse switch and the anti-reverse switch control circuit. The second voltage divider circuit includes a fourth resistor, a fifth resistor, and a sixth resistor. One end of the fourth resistor is connected to the output terminal of the second switching circuit. One end of the fifth resistor is connected to the other end of the fourth resistor, and the other end of the fifth resistor is connected to a grounding node. One end of the sixth resistor is connected to the connection node between the fourth and fifth resistors, and the other end of the sixth resistor is connected to the second input terminal of the control component.
[0012] Therefore, by linking the second switching circuit with the second detection point and the control component, and by using the second voltage divider circuit, which consists of the fourth to sixth resistors and is connected to the control component, the voltage of the corresponding node can be collected in a controlled and accurate manner, thereby improving the detection adaptability and reliability.
[0013] According to one embodiment of this application, the reverse protection switch is at least one of NMOS transistor, PMOS transistor, and diode. When the reverse protection switch is a PMOS transistor, a seventh resistor is provided between the gate and source of the PMOS transistor, and an eighth resistor is provided between the gate of the PMOS transistor and the ground node.
[0014] Therefore, by supporting the use of at least one of NMOS transistors, PMOS transistors, or diodes for the reverse protection switch, it can adapt to different application scenarios while ensuring the operational stability of the PMOS transistor, thus improving the adaptability and reliability of the reverse protection circuit.
[0015] According to the current monitoring device for the anti-reverse circuit proposed in this application embodiment, the current temperature of the anti-reverse circuit is collected, and the voltage value of the detection point of the anti-reverse switch in the anti-reverse circuit is determined according to the type of the anti-reverse switch and the current state of the vehicle. The non-inverting input terminal and the inverting input terminal of the first amplification unit and / or the second amplification unit are respectively connected to the two ends of the anti-reverse switch. The control component obtains the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to the current temperature, the voltage value of the detection point of the anti-reverse switch, and the output voltage of the first amplification unit and the second amplification unit. This solves the problems of large errors and high cost of sampling resistors in related technologies, and simultaneously monitors the sleep current and operating current of the area controller through a simple circuit, achieving simplicity.
[0016] To achieve the above objectives, a second aspect of this application provides a vehicle that includes a current monitoring device for the anti-reverse circuit shown in the first aspect embodiment.
[0017] To achieve the above objectives, a third aspect of this application provides a current monitoring method for an anti-reverse circuit. The method employs the current monitoring device for the anti-reverse circuit described in the first aspect embodiment, and includes the following steps: Obtain the current temperature of the anti-reverse circuit and the current status of the vehicle; Determine the voltage value of at least one detection point of the anti-reverse switch based on the type of the anti-reverse switch and the current state; Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit.
[0018] According to one embodiment of this application, the anti-reverse switch is an NMOS transistor, the current state is an operating state, and the step of obtaining the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, includes: Calculate the first voltage difference between the voltage values of the first detection point and the voltage values of the second detection point among the voltage values of the at least one detection point; Based on a preset temperature-pressure difference-impedance table, the on-resistance of the NMOS transistor is determined according to the first voltage difference and the current temperature, and the first actual voltage of the NMOS transistor is obtained according to the first output voltage of the first amplification unit and the first amplification factor of the first amplification unit. The operating current is obtained by the ratio of the first actual voltage of the NMOS transistor to the on-resistance of the NMOS transistor.
[0019] According to one embodiment of this application, the anti-reverse switch is an NMOS transistor, the current state is a sleep state, and the step of obtaining the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, includes: The second actual voltage of the NMOS transistor is obtained based on the first output voltage of the second amplification unit and the first amplification factor of the second amplification unit. Based on a preset temperature-voltage-current meter, the sleep current is obtained according to the current temperature and the second actual voltage of the NMOS transistor.
[0020] According to one embodiment of this application, the anti-reverse switch is a PMOS transistor, the current state is an operating state, and the step of obtaining the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, includes: The source voltage of the PMOS transistor is determined based on the voltage value of the first detection point among the voltage values of the at least one detection point, and the second voltage difference between the gate and source of the PMOS transistor is obtained based on the source voltage of the PMOS transistor, the resistance value of the seventh resistor and the resistance value of the eighth resistor. Based on a preset temperature-pressure difference-impedance table, the first on-resistance of the PMOS transistor is determined according to the second voltage difference and the current temperature, and the first actual voltage of the PMOS transistor is obtained according to the second output voltage of the first amplification unit and the second amplification factor of the first amplification unit. The operating current is obtained by the ratio of the first actual voltage of the PMOS transistor to the first on-resistance of the PMOS transistor.
[0021] According to one embodiment of this application, the anti-reverse switch is a PMOS transistor, the current state is a sleep state, and the step of obtaining the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, includes: The source voltage of the PMOS transistor is determined based on the voltage value of the first detection point among the voltage values of the at least one detection point, and the third voltage difference between the gate and source of the PMOS transistor is obtained based on the source voltage of the PMOS transistor, the resistance value of the seventh resistor and the resistance value of the eighth resistor. Based on a preset temperature-pressure difference-impedance table, the second on-resistance of the PMOS transistor is determined according to the third voltage difference and the current temperature, and the second actual voltage of the PMOS transistor is obtained according to the third output voltage of the first amplification unit and the third amplification factor of the first amplification unit. The quiescent current is obtained by the ratio of the second actual voltage of the PMOS transistor to the second on-resistance of the PMOS transistor.
[0022] According to one embodiment of this application, the anti-reverse switch is a diode. The step of obtaining the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, includes: The actual voltage of the diode is obtained based on the second output voltage of the second amplification unit and the second amplification factor of the second amplification unit. Based on a preset temperature-voltage-current meter, the dormant current is obtained according to the current temperature and the actual voltage of the diode.
[0023] According to the current monitoring method for the anti-reverse circuit proposed in this application embodiment, the current temperature of the anti-reverse circuit is collected, and the voltage value of the detection point of the anti-reverse switch in the anti-reverse circuit is determined according to the type of the anti-reverse switch and the current state of the vehicle. The non-inverting input terminal and the inverting input terminal of the first amplification unit and / or the second amplification unit are respectively connected to the two ends of the anti-reverse switch. Based on the type of the anti-reverse switch and the current state, the control component obtains the operating current or the sleep current of the anti-reverse circuit according to the current temperature, the voltage value of the detection point of the anti-reverse switch, and the output voltage of the first amplification unit and the second amplification unit. This solves the problems of large errors and high cost of sampling resistors in related technologies, and simultaneously monitors the sleep current and operating current of the area controller through a simple circuit, achieving a simple implementation.
[0024] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0025] Figure 1 This is a block diagram of a current monitoring device for an anti-reverse circuit provided according to an embodiment of this application; Figure 2 This is a schematic diagram of an NTC temperature acquisition circuit according to an embodiment of this application; Figure 3 This is a schematic diagram of an NMOS anti-reverse drive circuit according to an embodiment of this application; Figure 4 This is a schematic diagram of current monitoring in an NMOS anti-reverse circuit according to an embodiment of this application; Figure 5 This is a schematic diagram of the on-resistance characteristics of an NMOS according to an embodiment of this application; Figure 6 This is a schematic diagram of a source voltage acquisition circuit according to an embodiment of this application; Figure 7This is a schematic diagram of a gate voltage acquisition circuit according to an embodiment of this application; Figure 8 This is a schematic diagram illustrating the characteristics of an NMOS diode according to an embodiment of this application; Figure 9 This is a schematic diagram of current monitoring in a PMOS anti-reverse circuit according to an embodiment of this application; Figure 10 This is a flowchart of a current monitoring method for an anti-reverse circuit provided according to an embodiment of this application. Detailed Implementation
[0026] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0027] The following description, with reference to the accompanying drawings, describes a current monitoring device and method for a vehicle and an anti-reverse circuit according to embodiments of this application.
[0028] Figure 1 This is a block diagram of a current monitoring device for an anti-reverse circuit according to an embodiment of this application.
[0029] like Figure 1 As shown, the current monitoring device 10 of the anti-reverse circuit includes: an anti-reverse switch 100, a temperature acquisition component 200, a voltage detection module 300, an amplification component 400, and a control component 500.
[0030] The system includes a reverse protection switch 100 and a temperature acquisition component 200 for acquiring the current temperature of the reverse protection circuit; a voltage detection module 300, which includes a first voltage detection unit and / or a second voltage detection unit, wherein one end of the first voltage detection unit is connected to a first detection point, and one end of the second voltage detection unit is connected to a second detection point; and an amplification component 400, which includes a first amplification unit and / or a second amplification unit, wherein the non-inverting input terminal and the inverting input terminal of the first amplification unit are respectively connected to the two ends of the reverse protection switch 100, and the non-inverting input terminal and the inverting input terminal of the second amplification unit are respectively connected to the two ends of the reverse protection switch 100. The phase input terminals are respectively connected to the two ends of the anti-reverse switch 100; the control component 500 is respectively connected to the temperature acquisition component 200, the other end of the first voltage detection unit, the other end of the second voltage detection unit, the output terminal of the first amplification unit, and the output terminal of the second amplification unit. The control component 500 is configured to obtain the operating current or sleep current of the anti-reverse circuit based on the type and current state of the anti-reverse switch 100, according to at least one of the detection value of the first voltage detection unit, the detection value of the second voltage detection unit, the output voltage of the first amplification unit, and the first output voltage of the second amplification unit.
[0031] Here, "current temperature" refers to the actual temperature of the anti-reverse circuit in real-time, whether it is in operating or dormant state. "Vehicle's current state" refers to the vehicle's actual operating mode or mode at the current moment, such as operating or dormant state. "Operating current" refers to the real-time current flowing through the core circuit path when the vehicle is in a non-dormant operating state, such as driving, charging, or starting. "Dormant current" refers to the small current generated by the anti-reverse circuit to maintain basic standby functions when the vehicle is in a non-operating state, such as idle or dormant state.
[0032] Specifically, in this embodiment, the temperature acquisition component 200 can be a single-board temperature detection module. The current temperature of the anti-reverse circuit is obtained through the single-board temperature detection module. This module does not need to operate continuously for a long time; it is only for the purpose of handling the circuit, i.e., meeting basic detection requirements. The control component 500 only needs to be activated once at intervals to collect temperature data. A common implementation method is to use a local negative temperature coefficient thermistor (NTC) to sense the temperature. This embodiment has the advantages of obtaining temperature through local single-board temperature acquisition, which has small errors and the acquired temperature is the actual temperature of the single board. For example, such as Figure 2 As shown, Figure 2 This is a schematic diagram of an NTC temperature acquisition circuit according to an embodiment of this application. The embodiments of this application can be based on... Figure 2 The NTC temperature acquisition circuit shown collects the current temperature.
[0033] Furthermore, the voltage detection module 300 of this embodiment can adaptively select at least one key detection point and collect the voltage value of each detection point according to the type of the reverse protection switch 100 and the current state of the vehicle. The voltage detection module 300 includes a first voltage detection unit and / or a second voltage detection unit. The first voltage detection unit is used to detect the first terminal voltage of the reverse protection switch 100, and the second voltage detection unit is used to detect the second terminal voltage of the reverse protection switch 100. The signal amplification component 400 is composed of a first amplification unit and / or a second amplification unit, which adapts to the signal amplification requirements of different scenarios. The non-inverting input terminal and the inverting input terminal of the two amplification units are respectively connected to the two ends of the reverse protection switch 100 to amplify the voltage difference between the two ends of the device. The control component 500 calculates the operating current and sleep current of the reverse protection circuit based on the type of the reverse protection switch 100 and the current state of the vehicle by fusing and analyzing at least one parameter of the current temperature, the first terminal voltage of the reverse protection switch 100, the second terminal voltage of the reverse protection switch 100, the output voltage of the first amplification unit, and the output voltage of the second amplification unit. Among them, the control component 500 can be a microcontroller unit (MCU).
[0034] To facilitate those skilled in the art to further understand the current monitoring device of the anti-reverse circuit in the embodiments of this application, a detailed description is provided below with reference to specific embodiments.
[0035] Further, in some embodiments, the first voltage detection unit includes: a first switching circuit and a first voltage divider circuit, wherein the input terminal of the first switching circuit is connected to a first detection point, the output terminal of the first switching circuit is connected to the first voltage divider circuit, the control terminal of the first switching circuit is connected to the first output terminal of the control component, and the first switching circuit is configured to be in a closed state when a first closing signal is received, wherein the first detection point is the connection node between the anti-reverse switch 100 and the vehicle battery; the first voltage divider circuit includes a first resistor, a second resistor, and a third resistor, one end of the first resistor is connected to the output terminal of the first switching circuit, one end of the second resistor is connected to the other end of the first resistor, the other end of the second resistor is connected to a grounding node, one end of the third resistor is connected to the connection node between the first resistor and the second resistor, and the other end of the third resistor is connected to the first input terminal of the control component 500.
[0036] Optionally, in some embodiments, the second voltage detection unit includes: a second switching circuit and a second voltage divider circuit, wherein the input terminal of the second switching circuit is connected to a second detection point, the output terminal of the second switching circuit is connected to the second voltage divider circuit, the control terminal of the second switching circuit is connected to the second output terminal of the control component, and the second switching circuit is configured to be in a closed state when a second closing signal is received, wherein the second detection point is a connection node between the anti-reverse switch 100 and the anti-reverse switch control circuit; the second voltage divider circuit includes a fourth resistor, a fifth resistor, and a sixth resistor, one end of the fourth resistor is connected to the output terminal of the second switching circuit, one end of the fifth resistor is connected to the other end of the fourth resistor, the other end of the fifth resistor is connected to a grounding node, one end of the sixth resistor is connected to the connection node between the fourth and fifth resistors, and the other end of the sixth resistor is connected to the second input terminal of the control component.
[0037] Specifically, for example, taking the reverse protection switch 100 as an NMOS (N-Metal-Oxide-Semiconductor) transistor, such as... Figure 3 As shown, Figure 3 This is a schematic diagram of an NMOS anti-reverse drive circuit provided according to an embodiment of this application. If the current state of the vehicle is that the entire vehicle is operating, such as... Figure 4 As shown, Figure 4 This is a schematic diagram of an NMOS anti-reverse circuit current monitoring according to an embodiment of this application. When the vehicle is currently in the fully operational state, the NMOS transistor is in the ON state, and the gate-source voltage (Voltage between Gate and Source, V) is... GSVR is the voltage between the gate (G) and source (S) of an NMOS transistor. When this voltage exceeds a certain value, the source (S) and drain (D) exhibit resistive characteristics. Since the drain-source voltage is VR when the NMOS transistor is turned on... DS(on) The calculation formula is: ; Among them, R DS(on) I is the on-resistance; D This is the drain current, which is the main circuit current through the NMOS transistor.
[0038] In summary, by controlling component 500 to acquire the voltage of the NMOS transistor at this moment, the magnitude of the on-resistance is related to V. GS Depending on the current temperature, the control component can obtain the current I flowing through the NMOS transistor by acquiring the voltage and on-resistance of the NMOS at this time. D The specific process is as follows.
[0039] Specifically, such as Figure 5 As shown, Figure 5 This is a schematic diagram of the NMOS on-resistance characteristics according to an embodiment of this application, wherein, Figure 5 (a) is a schematic diagram of the on-resistance versus current curve at a certain temperature. Figure 5 (b) is a schematic diagram of the on-resistance versus temperature curves under certain current and voltage. For example, taking a certain semiconductor device as an example, its characteristics in the on-state are as follows. The requirement is that the NMOS anti-reverse circuit, upon startup, has V... GS The voltage must be at least 7V, this R DS(on) The magnitude of the conduction impedance R is independent of the conduction current. DS(on) Size and V GS It is related to temperature.
[0040] Furthermore, embodiments of this application can acquire the source voltage (S-terminal) of an NMOS transistor. Specifically, the source voltage acquisition is equivalent to battery voltage acquisition, which is performed using a first voltage detection unit. This first voltage detection unit consists of a first switching circuit and a first voltage divider circuit. The presence of the first switching circuit reduces the system's sleep current and allows the acquisition circuit to be shut down during system sleep mode. Voltage acquisition is achieved through the first voltage divider circuit, which is used to acquire the battery voltage. For example, using... Figure 6 For example, Figure 6 This is a schematic diagram of a source voltage acquisition circuit according to an embodiment of this application, wherein the first voltage divider circuit consists of a first resistor R5, a second resistor R9, and a third resistor R7. If the voltage detected by the first voltage detection unit is V... ADC1 Then the voltage VS at the S terminal is: ; The function of an ADC (Analog-to-Digital Converter) is to convert continuously changing analog signals into discrete digital signals so that digital circuits such as MCUs and processors can perform calculations, storage, and processing.
[0041] Furthermore, the gate voltage of the NMOS transistor is calculated using a similar method described above and detected by a second voltage detection unit, which consists of a second switching circuit and a second voltage divider circuit. For example, such as... Figure 7 As shown, Figure 7 This is a schematic diagram of a gate voltage acquisition circuit according to an embodiment of this application, wherein the second voltage divider circuit consists of a fourth resistor R19, a fifth resistor R20, and a sixth resistor R21. If the voltage acquired by the second voltage detection unit is V... ADC2 Then the voltage VG at the G terminal is: ; Therefore, the pressure difference V between the G and S electrodes GS for: ; After obtaining the VGS and board temperature information, the on-resistance R of the MOSFET can be obtained by inputting the calibration fitting MOSFET data pre-stored in the MCU. DS(on) There are various methods for calibrating and fitting MOS transistor data. One method is to use a table lookup and curve fitting. For example, as shown in Table 1, Table 1 shows the RDS(on) corresponding to different temperatures and VGS according to an embodiment of this application. From Table 1, it can be seen that the smaller the interval between temperature and VGS, the more accurate the data is, and the more samples there are, the more accurate the data is. For multiple samples, a weighted average method can be used.
[0042] Table 1
[0043] After obtaining V GS After obtaining the board temperature and other information, the calibration fitting MOSFET data pre-stored in the MCU can be input to obtain the on-resistance R of the MOSFET at this time. DS(on) Each sampling point can be fitted with a straight line, and the more sampling points there are, the more accurate the result.
[0044] R of NMOS transistor DS(on) All have a maximum value R DS(on)max If the maximum voltage of the MCU's ADC port is V MCUADC The rated maximum current of the electronic control unit (ECU) is set to I.DMAX Then the magnification factor of the first amplification unit of the amplification component 400 is: ; Where Y is the magnification factor of the first amplification unit.
[0045] A certain margin can be reserved to allow for a halved amplification factor. Even when the ECU reaches its maximum rated current, the MCU's ADC may not reach full scale, instead operating at half its full scale. Whether to reserve this margin and how much depends on actual needs. For example, the R of the IPC100N04S5-1R7... DS(on)max The rated maximum current I of the ECU is 2 ohms. DMAX If the amplification factor is 20A, then the amplification factor Y of the first amplification unit is: ; After reserving space, the magnification is halved, resulting in a magnification of 62.5x.
[0046] Based on the single-board temperature and V collected above GS The current on-resistance R is obtained by linear fitting between voltage ranges. DS(on) If the voltage collected by the MCU is V MCUADCOP2 With a magnification factor of Y, the actual NMOS voltage is V. MCUADCOP2 / If Y, then the current through the NMOS is: .
[0047] As another possible implementation, when the vehicle is in a sleep state, the NMOS is off, and the S and D terminals exhibit diode characteristics, which are temperature-dependent. For example, taking the IPC100N04S5-1R7 as an example... Figure 8 As shown, Figure 8 This is a schematic diagram illustrating the diode characteristics of an NMOS according to an embodiment of this application. In this case, the NMOS exhibits diode characteristics; at the same temperature, the greater the current through the diode, the higher the voltage V. SD The larger the voltage drop, the lower the temperature under the same diode current, V SD The greater the pressure drop, the higher the temperature and V measured by the temperature acquisition component 200. SD Pressure drop, through Figure 8 The curve shown can be used to find the current of the diode.
[0048] There are various methods for calibrating and fitting NMOS diodes. One method is to use a lookup table to fit a curve, measuring V at different temperatures and currents. SD As shown in Table 2, Table 2 shows the V values under different temperatures and currents according to an embodiment of this application. SDThe sampling interval for current and temperature can be selected based on the actual operating range of dormant current and temperature. The smaller the interval, the more accurate it is, but the larger the amount of data will be.
[0049] Table 2
[0050] The forward voltage drop of the NMOS diodes all has a maximum value V. SDMAX If the maximum voltage of the MCU's ADC port is V MCUADC Therefore, the magnification factor of the second amplification unit of amplification component 400 is: ; Where X is the magnification factor of the second amplification unit.
[0051] Similar to the overall vehicle operating state, a certain amount of space can be reserved for magnification. Whether to reserve space and how much to reserve depends on actual needs. For example, the V of IPC100N04S5-1R7 SDmax The voltage is 1.1V, and the amplification factor X of the second amplification unit is: ; Alternatively, based on the design's maximum sleep operating current, combined with... Figure 8 Get V SDMAX This type of amplification factor is larger, and the requirements for MCU sampling accuracy are lower. After reserving space, the amplification factor is halved to 2.25 times. Alternatively, no space can be reserved. A larger amplification factor results in higher voltage resolution and more accurate current calculation.
[0052] The temperature collected above and the voltage collected by the second amplification unit MCU are V. MCUADCOP1 The amplification factor of the second amplification unit is X, and the actual voltage V of the NMOS body diode is obtained. MCUADCOP1 The current flowing through the body diode of the NMOS is obtained by fitting the temperature and diode voltage through a table.
[0053] Therefore, taking NMOS as an example, the current of the anti-reverse circuit when the vehicle is in the current state of vehicle operation and vehicle sleep is calculated.
[0054] Optionally, in some embodiments, the reverse protection switch 100 is at least one of NMOS transistor, PMOS transistor and diode, wherein when the reverse protection switch 100 is a PMOS transistor, a seventh resistor is provided between the gate and source of the PMOS transistor, and an eighth resistor is provided between the gate of the PMOS transistor and the ground node.
[0055] Among them, PMOS (positive channel metal oxide semiconductor) is a field-effect transistor that uses holes as the main charge carriers.
[0056] Specifically, the above example uses an NMOS transistor to illustrate a reverse protection circuit for NMOS transistors. The following section uses PMOS transistors and diodes as examples for further explanation.
[0057] When the vehicle is currently in the fully operational state, the PMOS transistor is in the ON state, such as... Figure 9 As shown, Figure 9 This is a schematic diagram of current monitoring in a PMOS anti-reverse circuit according to an embodiment of this application. Figure 9 As shown, the PMOS does not necessarily sample the gate (G) voltage directly; it only needs to sample the source (S) voltage, i.e., the battery voltage, and then obtain the voltage through a voltage divider using resistors R1 and R2. If the sampled source voltage is V... S (The acquisition method is the same as that used in the NMOS transistor described above, and will not be elaborated further here.) Then, the voltage difference V between the gate and source (GS) is... GS for: ; Furthermore, in obtaining V GS Subsequently, under the vehicle's operating conditions, the current calculation method for the anti-reverse circuit with a PMOS switch type is the same as that for an NMOS switch, and will not be elaborated further here.
[0058] When the vehicle is in a sleep state, the current calculation method for the reverse protection circuit using a PMOS transistor as a switch is no different from that when the NMOS transistor is in the on state. The main difference is that when most ECUs are in operating mode, the rated maximum current of the ECU is I. DMAX Therefore, the magnification factor of the first amplification unit is: ; At this time, the ECU is in sleep mode, and the sleep current is small. In order to make the MCU's ADC sampling more accurate, the sleep current I is reduced. Dsleep Replace I Dmax Therefore, the operational amplifier gain Z is: ; In the vehicle's sleep state, apart from the op-amp multiplier, the current calculation method for the anti-reverse circuit with a PMOS transistor is the same as when the NMOS transistor is in the on state, so it will not be elaborated further here.
[0059] When the switch type is a diode, the calculation method is the same as when the vehicle is in sleep mode and the NMOS transistor is a switch type. It should be noted that when calculating the 400 amplification factor of the amplification component, the sleep current should be replaced with the operating current.
[0060] When the vehicle is in a sleep state, the MCU is often in sleep mode and cannot monitor the ADC. The MCU can be woken up periodically by an internal timer to monitor the ADC voltage value. If the voltage value exceeds the predetermined sleep current threshold, it is considered to have been woken up and the ECU starts the wake-up process. Alternatively, the ADC voltage value can be compared with the hardware threshold of the op-amp comparator. If the voltage value exceeds the threshold value, an interrupt is generated.
[0061] According to the current monitoring device for the anti-reverse circuit proposed in this application embodiment, the current temperature of the anti-reverse circuit is collected, and the voltage value of the detection point of the anti-reverse switch in the anti-reverse circuit is determined according to the type of the anti-reverse switch and the current state of the vehicle. The non-inverting input terminal and the inverting input terminal of the first amplification unit and / or the second amplification unit are respectively connected to the two ends of the anti-reverse switch. The control component obtains the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to the current temperature, the voltage value of the detection point of the anti-reverse switch, and the output voltage of the first amplification unit and the second amplification unit. This solves the problems of large errors and high cost of sampling resistors in related technologies, and simultaneously monitors the sleep current and operating current of the area controller through a simple circuit, achieving simplicity.
[0062] Secondly, this application provides a vehicle that includes... Figure 1 The current monitoring device for the anti-reverse circuit shown in the embodiment.
[0063] The vehicle proposed in the embodiments of this application solves the problems of large error and high cost of sampling resistor in related technologies by using the current monitoring device of the anti-reverse circuit described above. It can simultaneously monitor the sleep current and working current of the area controller through a simple circuit, which is simple to implement.
[0064] Furthermore, the current monitoring method for the anti-reverse circuit proposed according to an embodiment of this application is described with reference to the accompanying drawings.
[0065] Figure 10 This is a flowchart of a current monitoring method for an anti-reverse circuit according to an embodiment of this application.
[0066] In this embodiment, the current monitoring method of the anti-reverse circuit adopts... Figure 1 The current monitoring device for the anti-reverse circuit shown in the embodiment.
[0067] like Figure 10 As shown, the current monitoring method of this anti-reverse circuit includes the following steps: S1001, obtain the current temperature of the anti-reverse circuit and the current status of the vehicle; S1002, Determine the voltage value of at least one detection point of the anti-reverse switch according to the type of the anti-reverse switch and the current state; S1003, based on the type and current state of the anti-reverse switch, obtains the operating current or sleep current of the anti-reverse circuit according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit.
[0068] According to one embodiment of this application, the anti-reverse switch is an NMOS transistor, currently in an operating state. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: Calculate the first voltage difference between the voltage values of the first detection point and the voltage values of the second detection point, among the voltage values of at least one detection point; Based on the preset temperature-pressure difference-impedance table, the on-resistance of the NMOS transistor is determined according to the first voltage difference and the current temperature, and the first actual voltage of the NMOS transistor is obtained according to the first output voltage of the first amplification unit and the first amplification factor of the first amplification unit. The operating current is obtained by the ratio of the first actual voltage of the NMOS transistor to the on-resistance of the NMOS transistor.
[0069] According to one embodiment of this application, the anti-reverse switch is an NMOS transistor, currently in a sleep state. Based on the type of the anti-reverse switch and its current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The second actual voltage of the NMOS transistor is obtained based on the first output voltage of the second amplification unit and the first amplification factor of the second amplification unit. Based on a preset temperature-voltage-current meter, the sleep current is obtained according to the current temperature and the second actual voltage of the NMOS transistor.
[0070] According to one embodiment of this application, the anti-reverse switch is a PMOS transistor, currently in an operating state. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The source voltage of the PMOS transistor is determined based on the voltage value of the first detection point among the voltage values of at least one detection point, and the second voltage difference between the gate and source of the PMOS transistor is obtained based on the source voltage of the PMOS transistor, the resistance value of the seventh resistor and the resistance value of the eighth resistor. Based on the preset temperature-pressure difference-impedance table, the first on-resistance of the PMOS transistor is determined according to the second voltage difference and the current temperature, and the first actual voltage of the PMOS transistor is obtained according to the second output voltage of the first amplification unit and the second amplification factor of the first amplification unit. The operating current is obtained by the ratio of the first actual voltage of the PMOS transistor to the first on-resistance of the PMOS transistor.
[0071] According to one embodiment of this application, the anti-reverse switch is a PMOS transistor, currently in a dormant state. Based on the type of the anti-reverse switch and its current state, the operating current or dormant current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The source voltage of the PMOS transistor is determined based on the voltage value of the first detection point among the voltage values of at least one detection point, and the third voltage difference between the gate and source of the PMOS transistor is obtained based on the source voltage of the PMOS transistor, the resistance value of the seventh resistor and the resistance value of the eighth resistor. Based on the preset temperature-pressure difference-impedance table, the second on-resistance of the PMOS transistor is determined according to the third voltage difference and the current temperature, and the second actual voltage of the PMOS transistor is obtained according to the third output voltage of the first amplification unit and the third amplification factor of the first amplification unit. The quiescent current is obtained by the ratio of the second actual voltage of the PMOS transistor to the second on-resistance of the PMOS transistor.
[0072] According to one embodiment of this application, the anti-reverse switch is a diode. Based on the type of the anti-reverse switch and its current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The actual voltage of the diode is obtained based on the second output voltage of the second amplification unit and the second amplification factor of the second amplification unit. Based on a preset temperature-voltage-current meter, the dormant current is obtained according to the current temperature and the actual voltage of the diode.
[0073] It should be noted that the foregoing explanation of the current monitoring device embodiment for the anti-reverse circuit also applies to the current monitoring method of the anti-reverse circuit in this embodiment, and will not be repeated here.
[0074] According to the current monitoring method for the anti-reverse circuit proposed in this application embodiment, the current temperature of the anti-reverse circuit is collected, and the voltage value of the detection point of the anti-reverse switch in the anti-reverse circuit is determined according to the type of the anti-reverse switch and the current state of the vehicle. The non-inverting input terminal and the inverting input terminal of the first amplification unit and / or the second amplification unit are respectively connected to the two ends of the anti-reverse switch. Based on the type of the anti-reverse switch and the current state, the control component obtains the operating current or the sleep current of the anti-reverse circuit according to the current temperature, the voltage value of the detection point of the anti-reverse switch, and the output voltage of the first amplification unit and the second amplification unit. This solves the problems of large errors and high cost of sampling resistors in related technologies, and simultaneously monitors the sleep current and operating current of the area controller through a simple circuit, achieving a simple implementation.
[0075] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0076] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0077] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.
Claims
1. A current monitoring device for an anti-reverse circuit, characterized in that, include: Anti-reverse switch and temperature acquisition component for acquiring the current temperature of the anti-reverse circuit; A voltage detection module, comprising a first voltage detection unit and / or a second voltage detection unit, wherein one end of the first voltage detection unit is connected to a first detection point, and one end of the second voltage detection unit is connected to a second detection point; An amplification component, comprising a first amplification unit and / or a second amplification unit, wherein the non-inverting input terminal and the inverting input terminal of the first amplification unit are respectively connected to the two ends of an anti-reverse switch, and the non-inverting input terminal and the inverting input terminal of the second amplification unit are respectively connected to the two ends of an anti-reverse switch. A control component is connected to the temperature acquisition component, the other end of the first voltage detection unit, the other end of the second voltage detection unit, the output terminal of the first amplification unit, and the output terminal of the second amplification unit. The control component is configured to obtain the operating current or sleep current of the anti-reverse circuit based on the type of the anti-reverse switch and the current state, according to at least one of the detection values of the first voltage detection unit, the detection values of the second voltage detection unit, the output voltage of the first amplification unit, and the first output voltage of the second amplification unit.
2. The current monitoring device for the anti-reverse circuit according to claim 1, characterized in that, The first voltage detection unit includes: a first switching circuit and a first voltage divider circuit, wherein, The input terminal of the first switching circuit is connected to the first detection point, the output terminal of the first switching circuit is connected to the first voltage divider circuit, the control terminal of the first switching circuit is connected to the first output terminal of the control component, and the first switching circuit is configured to be in a closed state when a first closing signal is received. The first detection point is the connection node between the anti-reverse switch and the vehicle battery. The first voltage divider circuit includes a first resistor, a second resistor, and a third resistor. One end of the first resistor is connected to the output terminal of the first switching circuit. One end of the second resistor is connected to the other end of the first resistor. The other end of the second resistor is connected to a grounding node. One end of the third resistor is connected to the connection node between the first resistor and the second resistor. The other end of the third resistor is connected to the first input terminal of the control component.
3. The current monitoring device for the anti-reverse circuit according to claim 1 or 2, characterized in that, The second voltage detection unit includes: a second switching circuit and a second voltage divider circuit, wherein, The input terminal of the second switching circuit is connected to the second detection point, the output terminal of the second switching circuit is connected to the second voltage divider circuit, the control terminal of the second switching circuit is connected to the second output terminal of the control component, and the second switching circuit is configured to be in a closed state when a second closing signal is received. The second detection point is the connection node between the anti-reverse switch and the anti-reverse switch control circuit. The second voltage divider circuit includes a fourth resistor, a fifth resistor, and a sixth resistor. One end of the fourth resistor is connected to the output terminal of the second switching circuit. One end of the fifth resistor is connected to the other end of the fourth resistor, and the other end of the fifth resistor is connected to a grounding node. One end of the sixth resistor is connected to the connection node between the fourth and fifth resistors, and the other end of the sixth resistor is connected to the second input terminal of the control component.
4. The current monitoring device for the anti-reverse circuit according to claim 1, characterized in that, The reverse protection switch is at least one of NMOS transistor, PMOS transistor, and diode. When the reverse protection switch is a PMOS transistor, a seventh resistor is provided between the gate and source of the PMOS transistor, and an eighth resistor is provided between the gate of the PMOS transistor and the ground node.
5. A vehicle, characterized in that, include: The current monitoring device for the anti-reverse circuit as described in any one of claims 1-4.
6. A current monitoring method for an anti-reverse circuit, characterized in that, The method is applied to a current monitoring device for an anti-reverse circuit as described in any one of claims 1-4, wherein the method includes the following steps: Obtain the current temperature of the anti-reverse circuit and the current status of the vehicle; Determine the voltage value of at least one detection point of the anti-reverse switch based on the type of the anti-reverse switch and the current state; Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of the at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit.
7. The method according to claim 6, characterized in that, The anti-reverse switch is an NMOS transistor, and the current state is the operating state. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: Calculate the first voltage difference between the voltage values of the first detection point and the voltage values of the second detection point among the voltage values of the at least one detection point; Based on a preset temperature-pressure difference-impedance table, the on-resistance of the NMOS transistor is determined according to the first voltage difference and the current temperature, and the first actual voltage of the NMOS transistor is obtained according to the first output voltage of the first amplification unit and the first amplification factor of the first amplification unit. The operating current is obtained by the ratio of the first actual voltage of the NMOS transistor to the on-resistance of the NMOS transistor.
8. The method according to claim 6, characterized in that, The anti-reverse switch is an NMOS transistor, and the current state is a sleep state. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The second actual voltage of the NMOS transistor is obtained based on the first output voltage of the second amplification unit and the first amplification factor of the second amplification unit. Based on a preset temperature-voltage-current meter, the sleep current is obtained according to the current temperature and the second actual voltage of the NMOS transistor.
9. The method according to claim 6, characterized in that, The anti-reverse switch is a PMOS transistor, and the current state is the operating state. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The source voltage of the PMOS transistor is determined based on the voltage value of the first detection point among the voltage values of the at least one detection point, and the second voltage difference between the gate and source of the PMOS transistor is obtained based on the source voltage of the PMOS transistor, the resistance value of the seventh resistor and the resistance value of the eighth resistor. Based on a preset temperature-pressure difference-impedance table, the first on-resistance of the PMOS transistor is determined according to the second voltage difference and the current temperature, and the first actual voltage of the PMOS transistor is obtained according to the second output voltage of the first amplification unit and the second amplification factor of the first amplification unit. The operating current is obtained by the ratio of the first actual voltage of the PMOS transistor to the first on-resistance of the PMOS transistor.
10. The method according to claim 6, characterized in that, The anti-reverse switch is a PMOS transistor, and the current state is a sleep state. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The source voltage of the PMOS transistor is determined based on the voltage value of the first detection point among the voltage values of the at least one detection point, and the third voltage difference between the gate and source of the PMOS transistor is obtained based on the source voltage of the PMOS transistor, the resistance value of the seventh resistor and the resistance value of the eighth resistor. Based on a preset temperature-pressure difference-impedance table, the second on-resistance of the PMOS transistor is determined according to the third voltage difference and the current temperature, and the second actual voltage of the PMOS transistor is obtained according to the third output voltage of the first amplification unit and the third amplification factor of the first amplification unit. The quiescent current is obtained by the ratio of the second actual voltage of the PMOS transistor to the second on-resistance of the PMOS transistor.
11. The method according to claim 6, characterized in that, The anti-reverse switch is a diode. Based on the type of the anti-reverse switch and the current state, the operating current or sleep current of the anti-reverse circuit is obtained according to at least one of the current temperature, the voltage value of at least one detection point, the output voltage of the first amplification unit, and the output voltage of the second amplification unit, including: The actual voltage of the diode is obtained based on the second output voltage of the second amplification unit and the second amplification factor of the second amplification unit. Based on a preset temperature-voltage-current meter, the dormant current is obtained according to the current temperature and the actual voltage of the diode.