A large current starting control circuit based on mos transistor control on a motor vehicle

Abstract

The utility model relates to motor vehicle electrical control technical field discloses a kind of large current starting control circuit based on MOS tube control on motor vehicle, comprising: the main power path between battery and starting motor;Starting relay module, the including first metal oxide semiconductor tube MOSA and second metal oxide semiconductor tube MOSB, electrically connected on main power path, for as the controllable switch of starting loop;Drive control circuit IC, the starting relay module is electrically connected;Controller module;Communication module.In the utility model, MOS tube replaces traditional starting relay, and the large current on-off between battery and starting motor is realized by electronic switch, effectively avoid the device aging problem caused by physical contact wear, oxidation or adhesion and other factors, improve the reliability and service life of starting control circuit, maintain stable conduction performance.

Description

Technical Field

[0001] This utility model relates to the field of electrical control technology for motor vehicles, and in particular to a high-current start-up control circuit based on MOSFET control for motor vehicles. Background Technology

[0002] In the current automotive electronics field, engine starting requires the cooperation of a starter relay, starter motor, and spark plugs to complete ignition and starting. A starter relay is an electrical device commonly used to control the starting process of an electric motor. It acts as a switch in the circuit, starting or stopping the electric motor by controlling the flow of current. Traditional motor vehicles typically use mechanical starter relays to achieve the switching of large currents between the battery and the starter motor.

[0003] However, with current technology, mechanical relays are prone to unstable circuit conduction due to component aging during long-term use, which in turn affects the normal starting of the vehicle and its service life. Utility Model Content

[0004] To overcome the above deficiencies, this utility model provides a high-current start-up control circuit based on MOSFET control for motor vehicles, aiming to improve the problem of unstable circuit conduction, which affects the normal start-up and service life of the vehicle.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a high-current start-up control circuit based on MOSFET control for motor vehicles, comprising:

[0006] The main power path between the battery and the starter motor;

[0007] The start relay module includes a first metal-oxide-semiconductor transistor (MOSA) and a second metal-oxide-semiconductor transistor (MOSB), which are electrically connected to the main power supply path and are used as a controllable switch for the start circuit.

[0008] The drive control circuit IC is electrically connected to the start relay module and is used to provide the gate drive level to the MOS transistor according to the external switch signal or the control signal of the controller module. It also has overcurrent protection and temperature protection functions.

[0009] The controller module includes a microcontroller unit (MCU) that is electrically connected to the drive control circuit IC. The controller module is used to receive detection signals from the drive control circuit IC and output control signals.

[0010] A communication module, electrically connected to the controller module, is used to send control information to the vehicle control system;

[0011] A power load, electrically connected to the main power path, is used to receive battery power and operate.

[0012] By using the above technical solution, MOSFETs are used to replace traditional mechanical relays, realizing electronic control of the high-current circuit between the battery and the starter motor. Combined with the overcurrent and overtemperature protection functions of the drive control circuit, it can ensure reliable conduction of high current while having active protection capabilities. Through the cooperation of the controller module and the communication module, the circuit state can be logically managed and interact with the vehicle control system, thereby improving the stability and controllability of the starter control circuit.

[0013] Preferably, the first metal oxide semiconductor transistor (MOSA) and the second metal oxide semiconductor transistor (MOSB) are connected in series to enable the relay to operate without distinguishing between the motor side and the battery side.

[0014] By using the above technical solution, the first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB) are connected in series, giving the starting relay module a bidirectional conduction characteristic. This eliminates the need to distinguish between the motor side and the battery side when wiring the relay, freeing it from wiring direction restrictions, facilitating installation and layout, and preventing circuit abnormalities caused by wiring errors. This improves the applicability and reliability of the circuit. Furthermore, the first metal-oxide-semiconductor transistor (MOSA) can be composed of multiple transistors connected in parallel to achieve the function of a single MOSA. This, while maintaining the series connection with the second metal-oxide-semiconductor transistor (MOSB), shares the conduction pressure caused by high current, reduces the heat generation and loss of individual devices, and enhances the overall circuit's load-bearing capacity and reliability under high current starting conditions.

[0015] Preferably, when the drive control circuit IC detects that the current exceeds a preset range, it triggers overcurrent protection and controls the start relay module to turn off.

[0016] Through the above technical solution, when the drive control circuit IC detects that the current exceeds the preset range, it can promptly trigger the overcurrent protection logic, cancel the gate drive signal of the MOSFET, and turn off the start relay module, thereby cutting off the circuit between the battery and the starter motor, avoiding device damage or circuit abnormalities caused by overcurrent, and ensuring the safety and reliability of the circuit under high current start conditions.

[0017] Preferably, when the drive control circuit IC detects that the temperature exceeds a preset threshold, it triggers temperature protection and controls the start relay module to shut down.

[0018] With the above technical solution, when the drive control circuit IC detects that the temperature exceeds the preset threshold, it immediately triggers the temperature protection logic, cancels the gate drive signal of the MOSFET, shuts it off, cuts off the path between the battery and the starter motor, and ensures the safety and stability of the circuit operation.

[0019] Preferably, the drive control circuit IC includes a boost circuit for providing the required gate drive level for the first metal-oxide-semiconductor transistor MOSA and the second metal-oxide-semiconductor transistor MOSB.

[0020] Through the above technical solution, the drive control circuit IC boosts the battery voltage to the gate drive level required for the MOSFET to turn on, thereby ensuring that the first metal-oxide-semiconductor transistor MOSA and the second metal-oxide-semiconductor transistor MOSB can be turned on quickly and reliably under high current conditions, ensuring stable power supply from the battery to the starter motor and improving the overall reliability of the circuit.

[0021] Preferably, the drive control circuit IC is an integrated circuit IC, which includes functions such as boost, overcurrent protection, temperature protection, and wiring judgment.

[0022] Through the above technical solution, the drive control circuit adopts integrated circuit IC, which integrates functions such as boost, overcurrent protection, temperature protection and wiring judgment, to realize centralized driving and protection of MOSA and MOSB. While meeting the gate level requirements, it can quickly shut down the path when the current or temperature is abnormal, and judge the wiring status to avoid misconnection, thereby simplifying peripheral devices and wiring, reducing size and complexity, and improving the reliability and consistency of high current switching for startup.

[0023] Preferably, the drive control circuit IC can also be implemented using discrete components, including a boost circuit and devices for setting temperature protection and current protection thresholds.

[0024] Through the above technical solutions, the drive control circuit IC can be implemented not only by integrated chips, but also by discrete components, including boost circuits and devices for temperature protection and current protection threshold setting. Thus, it can be configured according to cost, design flexibility and device selection in different application scenarios, ensuring that the MOSFET has the required gate drive level and that overcurrent and overtemperature protection can be achieved through hardware, thereby improving the adaptability and reliability of the circuit design.

[0025] Preferably, the high-current start-up control circuit may further include a microcontroller unit (MCU) and a communication module within the controller module, used to perform logic control on the drive control circuit IC and send control information to the vehicle control system;

[0026] The MCU is an optional configuration. When the MCU is used by default, the hardware threshold protection for current and temperature is completed by the drive control circuit IC.

[0027] Through the above technical solution, the high-current start-up control circuit can optionally add a microcontroller unit (MCU) and a communication module to the drive control circuit IC. The MCU enables logic control and software protection of the drive control circuit IC, and the communication module sends relevant information to the vehicle control system. When no MCU is configured, the drive control circuit IC can independently complete the hardware threshold protection of current and temperature, thereby ensuring that the circuit has basic safety protection capabilities, while providing expandable intelligent and information interaction functions when needed.

[0028] This utility model has the following beneficial effects:

[0029] 1. In this utility model, a MOS transistor is used to replace the traditional starter relay, and a large current switching between the battery and the starter motor is achieved through an electronic switch. This effectively avoids the aging problem of the device caused by factors such as wear, oxidation or adhesion of physical contacts, improves the reliability and service life of the starter control circuit, and maintains stable conduction performance.

[0030] 2. In this utility model, a current and temperature detection protection mechanism is introduced into the drive control circuit to realize real-time monitoring of the entire process from power-on to startup. When the current exceeds the preset range or the temperature exceeds the limit, the protection logic can be triggered immediately and the MOSFET can be turned off, thereby avoiding short circuits, device damage and abnormal driving of the starting motor caused by overcurrent or overheating, and improving the safety of the circuit.

[0031] 3. In this utility model, a microcontroller unit (MCU) and a communication module are used in conjunction with the drive control circuit to realize the acquisition and transmission of circuit operation information. The current, temperature and control status information can be sent to the vehicle controller, thereby enabling the circuit to have information interaction and monitoring functions and improving the intelligence level of the charging control and detection circuit. Attached Figure Description

[0032] Figure 1 This utility model presents an architecture diagram of a high-current start-up control circuit based on MOSFET control for motor vehicles.

[0033] Figure 2 This invention provides a circuit diagram of an embodiment of a high-current start-up control circuit based on MOS transistor control for motor vehicles.

[0034] Figure 3 This is a circuit diagram of Embodiment 3 of a high-current start-up control circuit based on MOS transistor control for motor vehicles proposed in this utility model. Detailed Implementation

[0035] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0036] Reference Figures 1-3 This utility model provides an embodiment of a high-current start-up control circuit based on MOSFET control for motor vehicles, comprising:

[0037] The main power path between the battery and the starter motor;

[0038] The start relay module includes a first metal-oxide-semiconductor transistor (MOSA) and a second metal-oxide-semiconductor transistor (MOSB), which are electrically connected to the main power supply path and are used as a controllable switch for the start circuit.

[0039] The drive control circuit IC is electrically connected to the start relay module. It is used to provide the gate drive level to the MOSFET according to the external switch signal or the control signal of the controller module, and has overcurrent protection and temperature protection functions.

[0040] The controller module contains a microcontroller unit (MCU) that is electrically connected to the drive control circuit IC. It is used to receive detection signals from the drive control circuit IC and output control signals.

[0041] The communication module, electrically connected to the controller module, is used to send control information to the vehicle control system.

[0042] A power load, electrically connected to the main power path, is used to receive battery power and operate.

[0043] Specifically, the main power path is connected to the starter motor via the battery positive terminal through the starter relay module, and is also connected to the power load. This is used to provide a large current to the starter motor to drive the engine to start when the vehicle starts, and at the same time to supply power to the on-board power load, ensuring stable and reliable energy transmission during vehicle start-up and operation.

[0044] The starting relay module is equipped with module A and module B, which serve as interface terminals for high current paths. They are connected to the battery and the starter motor respectively to realize energy transfer from the battery to the starter motor. There is no fixed distinction between module A and module B in terms of structure, and the battery end and the motor end can be interchanged. The module itself is powered by the terminal connected to the battery, thereby ensuring that the module can achieve stable power supply and high current transmission under different installation methods.

[0045] The drive control circuit IC is electrically connected to the start relay module. It is used to provide the gate drive level to the MOSFET according to the external switch signal or the signal output by the controller module. The drive control circuit IC can be implemented by integrated circuit IC or built by discrete components. It has a boost circuit to provide sufficient gate level and has overcurrent protection and temperature protection functions, thereby ensuring the stability of the MOSFET under high current operation and cutting off the path in time in case of abnormality to protect the circuit and device.

[0046] The controller module can include a microcontroller unit (MCU), which is electrically connected to the drive control circuit IC. The MCU receives detection signals from the drive circuit and outputs control commands according to preset logic to control the on / off state of the MOSFETs, thereby achieving logical adjustment and management of the startup process. It should be noted that the MCU is not mandatory. With the MCU defaulted, the drive control circuit IC itself can perform hardware threshold protection for current and temperature, but it cannot provide software logic protection. The final hardware protection is configured and executed by the IC.

[0047] The communication module is electrically connected to the controller module and interacts with the vehicle control system through the vehicle communication bus. It uploads the status information of the controller module and the relevant detection information of the drive control circuit IC to the vehicle control system, so that the vehicle can monitor the operation of the starting circuit in real time and perform centralized management, realize information sharing and linkage, and improve the controllability and safety of the vehicle system.

[0048] The power load is electrically connected to the main power path through a branch circuit and is powered by the battery when the starter relay module is turned on. The power load can be high-power components in the vehicle such as air conditioning, heaters, and lighting equipment, ensuring that the high-current electrical equipment on the vehicle continuously receives stable power support during engine start-up and vehicle operation, thereby improving the reliable operation capability of the vehicle's electrical system.

[0049] The first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB) are connected in series to enable the relay to operate without distinguishing between the motor side and the battery side.

[0050] Specifically, the first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB) are connected in series, giving the starting relay module bidirectional symmetrical characteristics when it is turned on. This eliminates the need to distinguish between the motor side and the battery side when wiring the relay, meaning it is not restricted by the wiring direction. This structure facilitates installation and layout, avoids circuit abnormalities caused by incorrect wiring direction, and improves the applicability and reliability of the high-current starting control circuit.

[0051] Among them, the MOSA can be composed of multiple MOSFETs connected in parallel to share the conduction current under high current conditions, reduce the loss and heat pressure of individual devices, and further improve the circuit's load-bearing capacity and reliability.

[0052] When the drive control circuit IC detects that the current exceeds the preset range, it triggers the overcurrent protection and controls the start relay module to turn off.

[0053] When the drive control circuit IC detects that the current exceeds the preset range, it triggers the overcurrent protection and controls the start relay module to turn off.

[0054] Specifically, the drive control circuit IC includes current detection and temperature detection units. The current detection section monitors the current in the main power path in real time through a sampling resistor or current sampling chip and compares it with a preset threshold. When the detected current exceeds the preset range, the overcurrent protection logic is immediately triggered, canceling the drive level of the first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB), and turning off the start relay module. The temperature detection section collects the device temperature through sensors such as NTC. When the detected temperature exceeds the safety threshold, the over-temperature protection logic is also triggered, and the start relay module is turned off. This achieves active protection against electrical abnormalities during high-current startup, avoiding device failure and circuit damage caused by overcurrent or overheating, and ensuring the safe operation of the circuit and the entire vehicle system.

[0055] The drive control circuit IC includes a boost circuit for providing the required gate drive level for the first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB).

[0056] Specifically, the drive control circuit IC includes a boost circuit, which can adopt a BOOST circuit or other voltage boosting structure to boost the battery voltage to the gate level required for the first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB) to conduct. The boosted level is then stably applied to the gate port of the MOS transistor through a driver chip or discrete components, enabling it to conduct quickly and reliably during high-current startup. This ensures the normal operation of the start relay module and improves the stability and reliability of the vehicle start control circuit.

[0057] Example 1:

[0058] Reference Figure 2 Furthermore, the drive control circuit IC is an integrated circuit IC, which includes functions such as boost, overcurrent protection, temperature protection, and wiring judgment.

[0059] Specifically, Module A and Module B serve as main power interface terminals, connecting to the battery and starter motor respectively. The two ends are structurally symmetrical and can be interchanged depending on the installation. The module is powered by the terminal connected to the battery. When an external switch signal is input, the drive control circuit IC is implemented using an integrated circuit IC. The IC boosts the battery voltage to the gate drive level required by the MOSFET through a boost circuit, driving the first metal-oxide-semiconductor transistor MOSA and the second metal-oxide-semiconductor transistor MOSB to conduct sequentially or simultaneously, forming a closed path between Module A and Module B. The battery current is transmitted to the starter motor through the module to start the engine. When the IC detects that the current exceeds the preset range or the temperature is abnormal, it immediately cancels the drive signal, turns off the MOSFET, and cuts off the current path between Module A and Module B, thereby achieving overcurrent and overtemperature protection.

[0060] Example 2:

[0061] Furthermore, the drive control circuit IC can also be implemented using discrete components, including a boost circuit and devices for setting temperature protection and current protection thresholds.

[0062] Specifically, the drive control circuit IC can also be implemented using discrete components, including a boost circuit and devices for setting temperature and current protection thresholds. The boost circuit raises the battery voltage to the gate drive level required for the first MOSFET (MOSA) and the second MOSFET (MOSB) to conduct. The temperature and current protection devices detect the device's operating status and compare it with preset thresholds. When the temperature or current exceeds the threshold, protection logic is triggered, and the drive signal to the MOSFET is revoked, thereby shutting down the start-up relay module. Through this combination of discrete components, even without using integrated chips, it is possible to drive the MOSFETs, boost the voltage, and provide overcurrent and overtemperature protection, ensuring the stability and reliability of the high-current start-up control circuit.

[0063] Example 3:

[0064] Reference Figure 3 Furthermore, the high-current start-up control circuit may further include a microcontroller unit (MCU) and a communication module within the controller module, used to perform logic control on the drive control circuit IC and send control information to the vehicle control system.

[0065] The MCU is an optional configuration. When the MCU is used by default, the hardware threshold protection for current and temperature is completed by the drive control circuit IC.

[0066] Specifically, the high-current start-up control circuit, based on integrated circuit (IC) or discrete device implementation, also includes a microcontroller unit (MCU) and a communication module within the controller module. The communication module is electrically connected to the MCU and is used to send the status information of the drive circuit and the MCU to the vehicle control system through the vehicle communication bus, thereby realizing real-time monitoring of circuit operation and vehicle management.

[0067] Working Principle: The starter relay module includes MOSFETs MOSA and MOSFETB, which, together with the drive control circuit, control the on / off state of the high-current loop between the battery and the starter motor. The starter relay module has multiple interfaces, including a signal switch input for receiving external start / stop control signals (active low or active high) to implement start / stop logic control. Module A and Module B serve as main power interface terminals. When a switch signal is input, the drive control circuit, via a boost unit, raises the battery voltage to the gate drive level required for the MOSFETs to conduct, causing MOSA and MOSFETB to conduct sequentially or simultaneously. This forms a closed circuit between Module A and Module B, allowing battery current to flow through the MOSFETs to the starter motor, driving the engine for ignition and starting. The circuit collects the starting current in real time through a sampling resistor or detection device and compares it with a preset threshold. When the current exceeds the set range, the overcurrent protection logic is triggered, the drive of the MOSFET is removed, and the module enters the current protection mode, cutting off the path between the battery and the starter motor. At the same time, through the temperature detection unit, when the temperature of the MOSFET exceeds the preset threshold, the protection logic is also triggered, the MOSFET is turned off, and the module enters the temperature protection mode. This avoids damage to the device or abnormal motor drag caused by overcurrent or overheating, thus realizing electronic control of the high-current starting circuit. It can not only quickly supply power from the battery to the starter motor, but also actively cut off the path in abnormal situations, thereby improving the reliability and safety of the starting control circuit.

[0068] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A high-current start-up control circuit based on MOSFET control for motor vehicles, characterized in that: include: The main power path between the battery and the starter motor; The start relay module includes a first metal-oxide-semiconductor transistor (MOSA) and a second metal-oxide-semiconductor transistor (MOSB), which are electrically connected to the main power supply path and are used as a controllable switch for the start circuit. The drive control circuit IC is electrically connected to the start relay module and is used to provide the gate drive level to the MOS transistor according to the external switch signal or the control signal of the controller module. It also has overcurrent protection and temperature protection functions. The controller module includes a microcontroller unit (MCU) that is electrically connected to the drive control circuit IC. The controller module is used to receive detection signals from the drive control circuit IC and output control signals. A communication module, electrically connected to the controller module, is used to send control information to the vehicle control system; A power load, electrically connected to the main power path, is used to receive battery power and operate.

2. The high-current start-up control circuit based on MOSFET control for motor vehicles according to claim 1, characterized in that: The first metal-oxide-semiconductor transistor (MOSA) and the second metal-oxide-semiconductor transistor (MOSB) are connected in series to enable the relay to operate without distinguishing between the motor side and the battery side.

3. The high-current start-up control circuit based on MOSFET control for motor vehicles according to claim 1, characterized in that: When the drive control circuit IC detects that the current exceeds the preset range, it triggers overcurrent protection and controls the start relay module to turn off.

4. The high-current start-up control circuit based on MOSFET control for motor vehicles according to claim 1, characterized in that: When the drive control circuit IC detects that the temperature exceeds a preset threshold, it triggers temperature protection and controls the start relay module to shut down.

5. A high-current start-up control circuit based on MOSFET control for motor vehicles according to claim 1, characterized in that: The drive control circuit IC includes a boost circuit for providing the required gate drive level for the first metal-oxide-semiconductor transistor MOSA and the second metal-oxide-semiconductor transistor MOSB.

6. A high-current start-up control circuit based on MOSFET control for motor vehicles according to claim 1, characterized in that: The drive control circuit IC is an integrated circuit IC, which includes functions such as boost, overcurrent protection, temperature protection, and wiring judgment.

7. A high-current start-up control circuit for motor vehicles based on MOSFET control according to claim 1, characterized in that: The drive control circuit IC can also be implemented using discrete components, including a boost circuit and devices for setting temperature protection and current protection thresholds.

8. A high-current start-up control circuit based on MOSFET control for motor vehicles according to claim 1, characterized in that: The high-current start-up control circuit may further include a microcontroller unit (MCU) and a communication module within the controller module, used to perform logic control on the drive control circuit IC and send control information to the vehicle control system. The MCU is an optional configuration. When the MCU is used by default, the hardware threshold protection for current and temperature is completed by the drive control circuit IC.

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