Power supply protection circuit and vehicle

Abstract

The application discloses an electric protection circuit and a vehicle. The electric protection circuit comprises a power supply access end, a power supply output end, a current regulation module, a first resistor and a first triode. The first end of the first resistor is connected to the power supply access end, the second end of the first resistor is connected to the base of the first triode, the first pole of the first triode is connected to the power supply access end, the second pole of the first triode is connected to the power supply output end, and the first pole and the second pole are one of the collector and the emitter and the other one. The current regulation module is connected in parallel to the first end and the second end of the first resistor and is configured to regulate the current flowing through the first resistor and the base of the first triode by limiting the voltage across the first resistor, so that the current of the second pole of the first triode working in the amplification zone is limited. The application can meet the dual requirements of overcurrent protection and continuous power supply for the power supply protection circuit, thereby improving the power supply protection performance.

Description

Technical Field

[0001] This application relates to the field of power supply protection technology, and in particular to a power supply protection circuit and a vehicle. Background Technology

[0002] In power supply systems, power protection circuits are typically installed between power supply modules and power consumption modules to prevent damage to circuit components or equipment caused by abnormal operating conditions on the power supply side and / or the power consumption side. Overcurrent protection, as one of the core functions of power supply protection, aims to promptly cut off the current when the current in the circuit exceeds a preset safety threshold, preventing damage to the power consumption module due to overcurrent. Currently, commonly used overcurrent protection solutions in the industry mainly include fuse protection solutions and current detection and switching control solutions. Among them, the fuse protection solution uses a fuse as an overcurrent protection device. It utilizes the thermal effect of current; when the current flowing through the fuse exceeds the rated value, the fuse element melts due to heat, thereby cutting off the circuit. The current detection and switching control solution uses a current sampling resistor or Hall sensor to detect the output current in real time, compares the detected signal with a reference voltage, and when the detected current exceeds the threshold, it drives the switching device (such as a MOSFET) to turn off through control logic, thereby achieving overcurrent protection.

[0003] Most commonly used overcurrent protection solutions in the industry achieve this by directly cutting off the current, which cannot meet the dual requirements of overcurrent protection and continuous power supply. Therefore, how to enable power supply protection circuits to have better overcurrent protection functions is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a power supply protection circuit and vehicle that can simultaneously meet the dual requirements of overcurrent protection and continuous power supply, thereby improving power supply protection performance.

[0005] To achieve the above objectives: In a first aspect, embodiments of this application provide a power supply protection circuit, including a power input terminal, a power output terminal, a current regulation module, a first resistor, and a first transistor; a first end of the first resistor is connected to the power input terminal, a second end of the first resistor is connected to the base of the first transistor, a first terminal of the first transistor is connected to the power input terminal, and a second terminal of the first transistor is connected to the power output terminal, the first terminal and the second terminal being one of the collector and the other, respectively; the current regulation module is connected in parallel to the first and second ends of the first resistor, and is configured to regulate the current flowing through the first resistor and the base of the first transistor by limiting the voltage across the first resistor, so as to limit the current at the second terminal of the first transistor operating in the amplification region.

[0006] Optionally, the current regulation module includes a second transistor, the emitter and base of which are respectively connected to the two ends of the first resistor, and the voltage across the first resistor is limited by the emitter junction of the second transistor.

[0007] Optionally, the second transistor is a PNP transistor; the base of the second transistor is connected to the second terminal of the first resistor, the emitter of the second transistor is connected to the first terminal of the first resistor, and the collector of the second transistor is grounded.

[0008] Optionally, the power supply protection circuit also includes a device protection module; the device protection module is connected to the second transistor and is configured to provide overcurrent protection for the second transistor.

[0009] Optionally, the device protection module includes a third transistor and a second resistor, wherein the third transistor is a PNP transistor; the first terminal of the second resistor is connected to the collector of the second transistor, and the collector of the second transistor is grounded through the second resistor; the base of the third transistor is connected between the collector of the second transistor and the second resistor; the emitter of the third transistor is connected to the second terminal of the first resistor; and the collector of the second transistor is connected to the base of the first transistor.

[0010] Optionally, the power supply protection circuit further includes a first voltage clamping module; the first voltage clamping module is connected to the base of the first transistor and is configured to reduce the voltage of the base of the first transistor to a preset safe voltage when the power supply module dumps a load, so that the power supply output terminal connected to the emitter of the first transistor outputs a power supply voltage less than or equal to the preset safe voltage.

[0011] Optionally, the first voltage clamping module is a Zener diode; the base of the first transistor is grounded through the Zener diode.

[0012] Optionally, the power supply protection circuit may also include at least one of the following: The second voltage clamping module, connected between the first end of the first resistor and the power input terminal, is configured to reduce the increased voltage when the power module dumps a load and transmit the reduced voltage to the first resistor. The reverse power protection module is connected between the first end of the first resistor and the power input terminal and is configured to prevent reverse current from flowing into the power module. The voltage regulator module is connected to the power output terminal and is configured to stabilize the power output of the power supply terminal.

[0013] Optionally, the second voltage clamping module includes a transient voltage suppression diode.

[0014] Optionally, the power supply reverse protection module includes a reverse protection diode. Optionally, the voltage regulator module includes a voltage regulator capacitor.

[0015] Secondly, embodiments of this application provide a vehicle including a power module, a controller, and the power supply protection circuit described above; the controller is connected to the power module through the power supply protection circuit.

[0016] The technical solution provided in this application connects a current regulation module in parallel across a first resistor. By limiting the voltage across the first resistor using the current regulation module, the current flowing through the first resistor and the base of the first transistor is controlled. This limits the current at the second terminal (e.g., emitter) of the first transistor operating in the amplification region to a preset safe current. Compared to solutions that achieve overcurrent protection by directly cutting off the current, this technical solution can simultaneously provide overcurrent protection while continuously supplying power to the power module with a preset safe current, thus addressing both overcurrent protection and continuous power supply requirements and improving power supply protection performance. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0018] Figure 1 This is a first circuit structure diagram of the power supply protection circuit provided in the first embodiment of this application.

[0019] Figure 2 This is a second circuit structure diagram of the power supply protection circuit provided in the second embodiment of this application.

[0020] Figure 3 This is a third circuit structure diagram of the power supply protection circuit provided in the third embodiment of this application.

[0021] Figure 4 This is the fourth circuit structure diagram of the power supply protection circuit provided in the fourth embodiment of this application.

[0022] Figure 5 This is the fifth circuit structure diagram of the power supply protection circuit provided in the fourth embodiment of this application.

[0023] Figure 6 This is the sixth circuit structure diagram of the power supply protection circuit provided in the fifth embodiment of this application.

[0024] Figure 7 This is the seventh circuit structure diagram of the power supply protection circuit provided in the fifth embodiment of this application.

[0025] Figure 8This is the eighth circuit structure diagram of the power supply protection circuit provided in the sixth embodiment of this application.

[0026] The realization of the objectives, functional features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and textual descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0027] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0028] It should be understood that although the terms first, second, third, etc., may be used in this document to describe various information, elements, units, or modules, these information, elements, units, or modules should not be limited to these terms. These terms are only used to distinguish information, elements, units, or modules of the same type from one another.

[0029] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0030] In the following description, the use of suffixes such as "module," "part," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" may be used interchangeably.

[0031] First Embodiment See Figure 1 The first embodiment of this application (hereinafter referred to as "this embodiment") provides a power supply protection circuit, including a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1 and a first transistor Q1; Wherein, the first end of the first resistor R1 is connected to the power input terminal VBAT, the second end of the first resistor R1 is connected to the base of the first transistor Q1, the first terminal of the first transistor Q1 is connected to the power input terminal VBAT, and the second terminal of the first transistor Q1 is connected to the power output terminal Vout. The first terminal and the second terminal are respectively one of the collector and the other of the emitter. The current regulation module M1 is connected in parallel to the first and second ends of the first resistor R1. It is configured to regulate the current flowing through the first resistor R1 and the base of the first transistor Q1 by limiting the voltage across the first resistor R1, so as to limit the current at the second terminal of the first transistor Q1 operating in the amplification region.

[0032] The power input terminal VBAT is used to connect the power module to receive power current and voltage.

[0033] The power output terminal Vout is used to connect to the power module to supply power to the power module.

[0034] The first resistor R1 provides a path for the base current of the first transistor Q1, so that the power supply voltage is stepped down by the first resistor R1 to provide a forward bias voltage and base current to the base of the first transistor Q1.

[0035] Specifically, the resistance value of the first resistor R1 is determined by a combination of the preset safe current, the amplification factor of the first transistor Q1 when it is operating in the amplification region, and the voltage limit value of the current control module M1.

[0036] In one implementation, the first transistor Q1 can be an NPN transistor.

[0037] Understandably, when the first transistor Q1 is an NPN transistor, one of the conditions for an NPN transistor to operate in the amplification region is that the collector voltage is greater than the base voltage (expressed as VC > VB). Based on this condition, the collector voltage of the first transistor Q1 is mainly affected by the power supply voltage (e.g., VC = Vbat, representing the power supply voltage), and the base voltage of the first transistor Q1 is mainly affected by the voltage drop between the power supply and the first resistor R1 (e.g., ...). , (This represents the voltage drop across the first resistor R1). Based on the above analysis of the voltage data, it can be concluded that the collector voltage of the first transistor Q1 is greater than the base voltage of the first transistor Q1. Therefore, after the first transistor Q1 is connected to the power module at the power input terminal VBAT to receive the power supply current and voltage, it can operate in the amplification region.

[0038] Understandably, when the first transistor Q1 is operating in the amplification region, the amplification rule it follows is: the collector current (flowing from the collector to the emitter) is equal to the amplification factor in the device characteristics of the first transistor Q1 multiplied by the base current (flowing from the base to the emitter).

[0039] Specifically, the base current of the first transistor Q1 is mainly affected by the current flowing through the first resistor R1. Therefore, when the first transistor Q1 operates in the amplification region, its power supply output capability is affected by the current flowing through the first resistor R1. For example, the formula for calculating the power supply output capability of the first transistor Q1 when it operates in the amplification region is: , where represents the power output capability ( (Approximately equal to or equal to the collector current of the first transistor Q1). This represents the current flowing through the first resistor R1 ( (Approximately equal to or equal to the base current of the first transistor Q1). This represents the amplification factor in the device characteristics of the first transistor Q1. Therefore, by limiting the maximum current flowing through the first resistor R1, the maximum output capability of the first transistor Q1 can be made to correspond to a preset safe current, where the preset safe current can be either the maximum current that the power module can withstand during operation or a specific current calibrated.

[0040] In other embodiments, the polarity connection of the circuit can be adjusted so that the first transistor Q1 is a PNP transistor, and the condition for it to be in the amplification region is VE > VB > VC. In this case, the emitter of the first transistor Q1 is connected to the power supply input terminal VBAT, and the collector is connected to the power supply output terminal Vout. Based on a similar principle, the first transistor Q1 can also be made to work in the amplification region, which will not be repeated here.

[0041] Specifically, when the first transistor Q1 operates in the amplification region, it can dynamically adjust its power supply output capability (i.e., dynamically adjust the supply current) according to the load requirements (or current demand) of the power module. When the power supply output capability of the first transistor Q1 increases (the collector current increases), the base current of the first transistor Q1 will increase, causing the voltage across the first resistor R1 to rise. Thus, when the voltage across the first resistor R1 rises to a specific voltage, the current regulation module M1 can be triggered to clamp the voltage across the first resistor R1 to a specific voltage, thereby limiting the further increase of the power supply output capability of the first transistor Q1 (the collector current further increases). In other words, the first transistor Q1 reaches and maintains its maximum power supply output capability to supply power to the power module. The supply current represented by the maximum power supply output capability is less than or equal to the maximum safe current for maintaining the normal operation of the power module, thereby achieving continuous power supply to the power module with a preset safe current, taking into account both overcurrent protection and continuous power supply requirements.

[0042] In one embodiment, the current regulation module M1 can be a device capable of detecting the voltage across the first resistor R1 as the load requirement increases and clamping the voltage across the first resistor R1, or a current regulation circuit composed of one or more devices.

[0043] For example, the current regulation module M1 may be one of the following: a current regulation circuit composed of transistors, a current regulation circuit composed of Zener diode D1, or a digital circuit based on a controller. For example, in a current regulation circuit composed of Zener diode D1, the cathode of Zener diode D1 is connected to the power input terminal VBAT (the first end of the first resistor R1), and the anode is connected to the base of the first transistor Q1 (the second end of the first resistor R1). When Zener diode D1 is operating in the reverse breakdown region, the voltage across its terminals is clamped at a specific voltage. When the base current of the first transistor Q1 increases, causing the voltage across the first resistor R1 to rise and reach a specific voltage, Zener diode D1 breaks down and conducts, clamping the voltage across the first resistor R1 at the specific voltage, thereby limiting the further increase of the base current of the first transistor Q1.

[0044] The technical solution of this embodiment connects the current regulation module M1 in parallel across the first resistor R1. The current regulation module M1 limits the voltage across the first resistor R1, thereby regulating the current flowing through the first resistor R1 and the base of the first transistor Q1. This limits the emitter current of the first transistor Q1, which operates in the amplification region, to a preset safe current. Compared to solutions that achieve overcurrent protection by directly cutting off the current, this embodiment's technical solution can simultaneously provide overcurrent protection while continuously supplying power to the power module with a preset safe current, thus addressing both overcurrent protection and continuous power supply requirements and improving power supply protection performance.

[0045] Second Embodiment Based on the technical concept of the first embodiment of this application, see [reference] Figure 2 This embodiment further provides a power supply protection circuit, including a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1 and a first transistor Q1, and the current regulation module M1 includes a second transistor Q2. Wherein, the first end of the first resistor R1 is connected to the power input terminal VBAT, the second end of the first resistor R1 is connected to the base of the first transistor Q1, the collector of the first transistor Q1 is connected to the power input terminal VBAT, and the emitter of the first transistor Q1 is connected to the power output terminal Vout. The emitter and base of the second transistor Q2 are connected to the two ends of the first resistor R1, respectively, and the voltage across the first resistor R1 is limited by the emitter junction of the second transistor Q2.

[0046] In one embodiment, the second transistor Q2 is a PNP transistor; the base of the second transistor Q2 is connected to the second terminal of the first resistor R1, the emitter of the second transistor Q2 is connected to the first terminal of the first resistor R1, and the collector of the second transistor Q2 is grounded.

[0047] Specifically, when the second transistor Q2 is operating in the amplification region, it can clamp the voltage across the first resistor R1 to the saturation voltage drop of the emitter-collector of the second transistor Q2, thereby limiting the maximum current of the first resistor R1 and the base of the first transistor Q1, so that the current of the emitter of the first transistor Q1 operating in the amplification region is limited.

[0048] Understandably, when the power module is supplying power normally and the power supply current at the power output terminal Vout increases, causing the voltage drop across the first resistor R1 to increase and the second transistor Q2 to switch to the amplification region (for example, in the case of a damaged or short-circuited power module causing overcurrent), the second transistor Q2 can make the maximum voltage across the first resistor R1 equal to the saturation voltage drop across the emitter-collector of the second transistor Q2. This allows the base current of the first transistor Q1 to be limited by the first resistor R1 and the maximum voltage across it, thereby limiting the emitter current of the first transistor Q1 operating in the amplification region.

[0049] Understandably, when the emitter voltage of a PNP transistor is greater than the base voltage and the base voltage is greater than the collector voltage, the PNP transistor operates in the amplification region.

[0050] Specifically, when the power module is damaged or short-circuited, causing overcurrent, the collector current of the first transistor Q1, which operates in the amplification region, increases proportionally. This increases the current flowing through the first resistor R1, resulting in an increase in the voltage drop across the first resistor R1. Consequently, the emitter-junction voltage difference of the second transistor Q2, which is connected in parallel with the first resistor R1 through its emitter and base, increases (the emitter voltage is greater than the base voltage, and the base voltage is greater than the collector voltage), causing the second transistor Q2 to operate in the amplification region.

[0051] Understandably, when the power module is supplying power normally and the power supply current output at the power output terminal Vout is within the preset safe current, the voltage difference across the first resistor R1 is very small. Therefore, the emitter-junction voltage difference of the second transistor Q2, which is connected in parallel with the first resistor R1 through the emitter and base, is very small (less than the turn-on voltage), and the turn-on condition of the second transistor Q2 is not met. Therefore, the second transistor Q2 is in the off state. Thus, the current flowing through the first resistor R1 is mainly affected by the collector current of the first transistor Q1 in the working amplification region. Therefore, when the collector current increases, the current flowing through the first resistor R1 to the base of the first transistor Q1 increases synchronously. The power supply output capability of the first transistor Q1 is dynamically adjusted according to the load change, and the output voltage value of the first transistor Q1 changes dynamically with the power supply voltage.

[0052] The technical solution of this embodiment limits the voltage across the first resistor R1 by using the emitter junction of the second transistor Q2. Voltage clamping is achieved by utilizing the PN junction characteristics of the emitter junction of the second transistor Q2. This method is simple in structure, low in cost, and has a fast response speed (nanosecond level). Therefore, the technical solution of this embodiment achieves higher reliability and lower power consumption while fulfilling the dual requirements of overcurrent protection and continuous power supply, without requiring additional control logic circuitry.

[0053] Third Embodiment Based on the technical concept of the second embodiment of this application, this embodiment further provides a power supply protection circuit, including a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1, a first transistor Q1 and a device protection module, wherein the current regulation module M1 includes a second transistor Q2. Wherein, the first end of the first resistor R1 is connected to the power input terminal VBAT, the second end of the first resistor R1 is connected to the base of the first transistor Q1, the collector of the first transistor Q1 is connected to the power input terminal VBAT, and the emitter of the first transistor Q1 is connected to the power output terminal Vout. The emitter and base of the second transistor Q2 are connected to the two ends of the first resistor R1, respectively, and the voltage across the first resistor R1 is limited by the emitter junction of the second transistor Q2. The device protection module is connected to the second transistor Q2 and is configured to provide overcurrent protection for the second transistor Q2.

[0054] In one embodiment, the second transistor Q2 is a PNP transistor; the base of the second transistor Q2 is connected to the second terminal of the first resistor R1, the emitter of the second transistor Q2 is connected to the first terminal of the first resistor R1, and the collector of the second transistor Q2 is grounded.

[0055] Specifically, when the second transistor Q2 is operating in the amplification region, it can clamp the voltage across the first resistor R1 to the saturation voltage drop of the emitter-collector of the second transistor Q2, thereby limiting the maximum current of the first resistor R1 and the base of the first transistor Q1, so that the current of the emitter of the first transistor Q1 operating in the amplification region is limited.

[0056] Understandably, the second transistor Q2 is connected in parallel across R1 through its emitter and base. Under normal operation (such as when the power module is supplying power normally and the power supply current output at the power output terminal Vout is within the preset safe current), a small current flows through the second transistor Q2. When the second transistor Q2 enters the conduction state or operates in the amplification region, the path from the emitter to the collector of the second transistor Q2 may bear a large current. Therefore, when the collector current of the second transistor Q2 is too large, the second transistor Q2 may be at risk of thermal damage due to excessive power consumption.

[0057] Specifically, the device protection module and the second transistor Q2 are configured to monitor the operating current or operating voltage of the second transistor Q2, and when the operating parameters of the second transistor Q2 exceed the safety threshold, reduce the current stress of the second transistor Q2 through a current shunting or current limiting mechanism, thereby preventing the second transistor Q2 from being damaged due to overcurrent or overpowering.

[0058] In one implementation, see [reference] Figure 3 The device protection module includes a third transistor Q3 and a second resistor R2. The third transistor Q3 is a PNP transistor. The first end of the second resistor R2 is connected to the collector of the second transistor Q2, and the collector of the second transistor Q2 is grounded through the second resistor R2. The base of the third transistor Q3 is connected between the collector of the second transistor Q2 and the second resistor R2. The emitter of the third transistor Q3 is connected to the second end of the first resistor R1. The collector of the second transistor Q2 is connected to the base of the first transistor Q1.

[0059] Understandably, the device protection module can make the third transistor Q3 work in the saturation region by reasonably setting the resistance characteristics of the second resistor R2, so as to achieve overcurrent protection for the second transistor Q2.

[0060] Understandably, the rule for a PNP transistor to operate in the saturation region is that the emitter voltage is greater than the base voltage and the collector voltage is greater than the base voltage. Specifically, the base voltage of the third transistor Q3 is equal to the emitter voltage minus the Veb forward voltage drop, and the collector voltage is equal to the emitter voltage minus the forward voltage drop. Thus, by using the second resistor R2 in conjunction with the second transistor Q2, the third transistor Q3 can operate in the saturation region.

[0061] Specifically, the second resistor R2 connected to the third transistor Q3 serves as a compromise between "functionality" and "interference immunity." Regarding "functionality," using the limiting principle, if the resistance of the second resistor R2 were 0Ω, the current path from the first resistor R1, through the emitter to the base of the third transistor Q3, and then through the second resistor R2 would be very large. This would result in a large voltage drop across the first resistor R1, potentially triggering the overcurrent limiting function of the current control module M1. Therefore, to ensure the "functionality" of the third transistor Q3, the resistance of the second resistor R2 cannot be too small and should be greater than the first specific resistance value. Regarding "interference immunity," since engineering machinery operates in high EMC (electromagnetic interference) environments, it's crucial to consider how to improve the module's electromagnetic interference immunity. This capability depends on the circuit's current capability, which can absorb the current coupled into the circuit by the electromagnetic field. Typically, in hardware design, this current needs to reach the μA level. Based on the above, the current in the path from the first resistor R1, through the emitter to the base of the third transistor Q3, and through the second resistor R2 must not be too small (it must be at least in the μA range). Therefore, the resistance of the second resistor R2 cannot be infinite (it must be less than the second specific resistance value). Considering both "functionality" and "interference immunity," the resistance of the second resistor R2 must be greater than the first specific resistance value and less than the second specific resistance value. Therefore, the combination of the second resistor R2 and the third transistor Q3 in the device protection module can ensure both the "functionality" and "interference immunity" of the module.

[0062] Understandably, when the third transistor Q3 is in the saturation region, the current flowing through the first resistor R1 can flow through the third transistor Q3 from the emitter to the collector without loss, and then be transmitted to the base of the first transistor Q1.

[0063] Specifically, the second resistor R2 in the device protection module converts the current at the collector of the second transistor Q2 into a comparable voltage signal, and enables the third transistor Q3 to operate in the saturation region. Through its emitter and collector, the current flowing through the first resistor R1 is transmitted to the base of the first transistor Q1, and the current at the collector of the second transistor Q2 is shunted to limit the power consumption of the second transistor Q2 and achieve overcurrent protection.

[0064] In another embodiment, the device protection module includes a Zener diode (D1) and a third resistor; wherein the collector of the second transistor Q2 is grounded through the Zener diode D1, and the third resistor is connected in series with the Zener diode D1. Thus, the device protection module can utilize the breakdown effect of the Zener diode D1 to clamp the collector voltage of the second transistor Q2 operating in the amplification region, thereby shunting the collector current of the second transistor Q2 and limiting its power consumption to achieve overcurrent protection.

[0065] The technical solution of this embodiment, through the device protection module, can protect the second transistor Q2 from damage under abnormal operating conditions (such as damage to the power module or short circuit leading to overcurrent), thereby improving the reliability and robustness of the circuit and extending the service life of the circuit devices.

[0066] Fourth embodiment Based on the technical concept of the second or third embodiment of this application, this embodiment further provides a power supply protection circuit, which also includes a first voltage clamping module. Specifically, the power supply protection circuit includes a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1, a first transistor Q1, and a first voltage clamping module, wherein the current regulation module M1 includes a second transistor Q2; or, the power supply protection circuit includes a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1, a first transistor Q1, a device protection module, and a first voltage clamping module, wherein the current regulation module M1 includes a second transistor Q2.

[0067] The first voltage clamping module is connected to the base of the first transistor Q1 and is configured to reduce the voltage of the base of the first transistor Q1 to a preset safe voltage when the power module dumps a load, so that the power output terminal Vout connected to the emitter of the first transistor Q1 outputs a supply voltage less than or equal to the preset safe voltage.

[0068] Understandably, when a power module includes a generator and a battery / large load, and the power module supplies power to the power-consuming modules, if the generator is operating and the battery / large load connected to the generator is suddenly disconnected (i.e., load dump), the output of the power module will experience a voltage surge (or load dump surge voltage, i.e., a transient high voltage with a rapid increase in voltage) caused by the sudden change in load. For example, in a vehicle electronic system, the power module (such as a generator connected to a battery) supplies power to the power-consuming modules (such as various on-board electronic control units). When the battery connection is suddenly disconnected during vehicle operation (e.g., due to a loose cable, corrosion and breakage of the battery terminals, or intentional disconnection), the load power of the battery module drops sharply, and the output of the power module will output a load dump surge voltage.

[0069] Understandably, a power module can refer to a power supply unit capable of providing electrical energy to a power-consuming module, and whose output voltage may experience transient overvoltage due to load changes. For example, a power module can be a generator in a vehicle power supply system, and the generator is connected to a battery to charge the connected battery during operation; that is, the battery is the load.

[0070] Understandably, an electrical module can refer to a functional unit that receives electrical energy output from a power supply module to perform a specific function, and whose normal operation and safe operation depend on the supply voltage and / or supply current being within a defined range. For example, an electrical module may be a controller or other functional module in a vehicle.

[0071] Understandably, at least one of the power supply module and the power consumption module can be a characteristic of the operating environment (i.e., not included in the power supply protection circuit), or at least one of the power supply module and the power consumption module can also be included in the power supply protection circuit.

[0072] The power supply protection circuit of this embodiment can, independently or in conjunction with other circuit modules, use a first voltage clamping module to precisely reduce the voltage transmitted to the base of the first transistor Q1 to a preset safe voltage. Utilizing the emitter-following characteristic of the first transistor Q1, the power output terminal Vout connected to the emitter of the first transistor Q1 outputs a supply voltage less than or equal to the preset safe voltage to the power output terminal Vout, ensuring that the power-consuming module connected to the power output terminal Vout operates within its withstand voltage range. Therefore, the technical solution of this embodiment enables the power supply protection circuit to possess a collaborative protection mechanism of basic load dump protection and overcurrent protection, thereby improving power supply protection performance. In one embodiment, see [reference needed]. Figure 4 or Figure 5 The first voltage clamping module can be a Zener diode D1; the base of the first transistor Q1 is grounded through the Zener diode D1.

[0073] Thus, when the power module throws a load, the voltage transmitted through the first resistor R1 to the base of the first transistor Q1 is clamped to the preset safe voltage by the Zener diode D1, so that the emitter of the first transistor Q1 outputs a supply voltage less than or equal to the preset safe voltage to the power output terminal Vout.

[0074] Understandably, the preset safety voltage can be adjusted by selecting the Zener diode D1; in other words, the preset safety voltage is directly related to the device characteristics of the selected Zener diode D1.

[0075] In another implementation, the first voltage clamping module can be a Zener diode D1, or it can be a transient voltage suppressor (such as a TVS diode), an active MOSFET clamping scheme, or a digital controller composed of a chip or controller assembly. Among them, the active MOSFET clamping scheme can utilize the linear operating region of the MOSFET, and its conduction level can be controlled by a voltage detection circuit to achieve adjustable and programmable precise clamping.

[0076] Fifth Embodiment Based on the technical concept of the fourth embodiment of this application, this embodiment further provides a power supply protection circuit, which also includes a second voltage clamping module. Specifically, the power supply protection circuit includes a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1, a first transistor Q1, a first voltage clamping module, and a second voltage clamping module, wherein the current regulation module M1 includes a second transistor Q2; or, the power supply protection circuit includes a power input terminal VBAT, a power output terminal Vout, a current regulation module M1, a first resistor R1, a first transistor Q1, a device protection module, a first voltage clamping module, and a second voltage clamping module, wherein the current regulation module M1 includes a second transistor Q2.

[0077] The second voltage clamping module is connected between the first end of the first resistor R1 and the power input terminal VBAT. It is configured to reduce the increased voltage when the power module dumps the load and transmit the reduced voltage to the first resistor R1.

[0078] Understandably, the voltage clamping capability of the second voltage clamping module may be the same as or different from that of the first voltage clamping module.

[0079] In one implementation, see [reference] Figure 6 , Figure 7 The second voltage clamping module includes a transient voltage suppressor diode D2 (or TVS diode). One end of the transient voltage suppressor diode D2 is connected between the power input terminal VBAT and the first terminal of the first resistor R1, and the other end of the transient voltage suppressor diode D2 is grounded.

[0080] Among them, the transient voltage suppressor diode D2 is an avalanche breakdown type device, which includes three states: cutoff state, the voltage across the transient voltage suppressor diode D2 is less than the breakdown voltage, high impedance, minimal leakage current, and does not affect normal power supply; breakdown state, the voltage across the transient voltage suppressor diode D2 is greater than or equal to the breakdown voltage (in the case of load dump inrush voltage), low dynamic resistance, large current discharge, and reduces the load dump inrush voltage by clamping voltage (such as the aforementioned breakdown voltage or a voltage calculated based on the breakdown voltage and device characteristic parameters); recovery state, after the load dump inrush voltage (i.e., transient overvoltage) disappears, it automatically returns to the high impedance state to the cutoff state.

[0081] In the technical solution of this embodiment, the second voltage clamping module can quickly respond to transient overvoltage during load dumping, achieving nanosecond-level overvoltage protection action.

[0082] In some implementations, when selecting the transient voltage suppressor diode D2, its nominal clamping voltage is usually chosen to match the upper limit of the power module's withstand voltage. With this configuration, the actual clamping voltage obtained by the transient voltage suppressor diode D2 when clamping the inrush current voltage is usually higher than its nominal clamping voltage. Therefore, the technical solution of this embodiment can use a first voltage clamping module to perform more precise voltage clamping on the actual clamping voltage, thereby stabilizing and reducing the actual clamping voltage output by the second voltage clamping module to a preset safe voltage (the preset safe voltage meets the withstand voltage requirements of the power module and is less than or equal to the upper limit of the power module's withstand voltage), thus ensuring that the power module operates within its withstand voltage range. For example, taking a controller with a standard operating voltage of 24V powered by a vehicle's power supply system as an example, a controller with a standard operating voltage of 24V is generally required not to burn out components when subjected to an overvoltage of 36V. Therefore, the nominal clamping voltage of the transient voltage suppression diode D2 in the second voltage clamping module is usually selected to be around 36V. However, the transient voltage generated when the power supply module of the power supply system dumps a load can reach around 200V. In this case, the actual clamping voltage obtained by voltage clamping through the transient voltage suppression diode D2 is usually around 53 to 58V. Therefore, directly outputting this actual clamping voltage to the controller poses a risk of burning out the components in the controller. Therefore, the technical solution of this embodiment can perform more precise voltage clamping on the actual clamping voltage through the first voltage clamping module to stably reduce the actual clamping voltage output by the second voltage clamping module to a preset safe voltage (e.g., a voltage greater than 24V and lower than 36V, such as around 32V), thereby ensuring that the power module operates within its withstand voltage range.

[0083] In another embodiment, the second voltage clamping module can achieve initial voltage clamping not only through the transient voltage suppression diode D2, but also through other devices or circuits. For example, other devices that can replace the transient voltage suppression diode D2 include metal oxide varistors (MOVs), semiconductor avalanche diodes (such as Zener diodes / ZnD diodes), thyristor surge protection devices, etc. The MOV utilizes the nonlinear current-voltage characteristics of the metal oxide grain interface; its resistance drops sharply under overvoltage, shunting the surge current. The semiconductor avalanche diode reverse-breaks down into the avalanche multiplication region, maintaining an approximately constant voltage and dissipating surge energy. The thyristor surge protection device triggers the thyristor structure to conduct under overvoltage, entering a low-resistance latch-up state, with the large current bypassed to ground. For example, the circuit that can replace the transient voltage suppression diode D2 can be an RCD snubber circuit (including resistor, capacitor, and diode), a switching surge suppressor (integrated protection IC), or an active clamping circuit (transistor / MOSFET active control), etc. In the RCD snubber circuit, when overvoltage occurs, the diode conducts to charge the capacitor, the capacitor voltage rises to absorb energy, and a discharge path is provided through the resistor. The switching surge suppressor integrates a dedicated chip for voltage detection, logic control, and power switching to achieve programmable surge suppression. The active clamping circuit detects the voltage in real time, and when overvoltage occurs, it actively turns on the MOSFET to form a discharge path, regulating the clamping voltage in a closed loop. Furthermore, the second voltage clamping module can be an active MOSFET clamping scheme, a digital controller composed of a chip or controller assembly, etc.

[0084] When the power module throws a load, the first voltage (the aforementioned actual clamping voltage) obtained by stepping down the transient voltage suppression diode D2 of the second voltage clamping module is transmitted to the base of the first transistor Q1 through the first resistor R1. The Zener diode D1 of the first voltage clamping module clamps the first voltage to a preset safe voltage, so that after the base of the first transistor Q1 is connected to the preset safe voltage, a supply voltage less than or equal to the preset safe voltage is output to the power output terminal Vout through the emitter of the first transistor Q1. The output voltage meets the voltage withstand requirements of the power module, and / or the preset safe voltage meets the voltage withstand requirements of the power module.

[0085] Understandably, when the power module throws a load, the power supply protection circuit, equipped with a transient voltage suppression diode D2, will experience a high transient voltage (i.e., the first voltage). This transient voltage is applied to the Zener diode D1 through the first resistor R1 and the third transistor Q3 (if present). The Zener diode D1 will clamp this transient voltage to a preset safe voltage. Thus, the base of the first transistor Q1 is at the preset safe voltage, and the emitter of the first transistor Q1 outputs a supply voltage that is lower than the preset safe voltage. Therefore, the power supply protection circuit can accurately adjust the output voltage, thereby reducing the voltage withstand requirement of the power module. Furthermore, the reduced voltage withstand requirement of the power module also reduces its cost.

[0086] In the technical solution of this embodiment, when the power module throws a load, the first voltage clamping module of the power supply protection circuit can clamp the voltage output by the second voltage clamping module to a preset safe voltage, and limit the power supply current of the power output terminal Vout to within a preset safe current. Thus, the technical solution of this embodiment realizes two-stage transient voltage clamping to ensure that the power supply voltage meets the withstand voltage requirements of the power consumption module. In addition, the power supply protection circuit can also limit the current when the power consumption module experiences an overcurrent situation to realize a non-power-off overcurrent protection function.

[0087] The technical solution of this embodiment can quickly and accurately clamp the transient high voltage of the load dump to a lower voltage value to obtain the supply voltage when the power module dumps a load, so as to effectively avoid the problem of high voltage damaging the components in the power module (such as chip breakdown). Furthermore, the power supply protection circuit provided in this embodiment has a simple circuit structure and can use low-cost electrical components (such as resistors, transistors, etc.), which not only reduces the cost of the power supply system, but also helps to reduce the withstand voltage design requirements of the power module, thereby reducing the production cost of the power module.

[0088] The technical solution of this embodiment can also quickly limit the power supply current when the power module is short-circuited or damaged, and the power module does not have current limiting function or multiple power protection functions, so as to avoid the power supply current being too large and causing irreversible damage to the power module. Thus, the power supply protection circuit provided in this embodiment can improve the safety of the power supply system and can be adapted to low-cost power modules.

[0089] Sixth Embodiment Based on the technical concept of any one of the first to fifth embodiments of this application, this embodiment further provides a power supply protection circuit, which also includes a power reverse protection module.

[0090] The reverse current protection module is connected between the first end of the first resistor R1 and the power input terminal VBAT, and is configured to prevent reverse current from flowing into the power module.

[0091] In one implementation, see [reference] Figure 8 The power supply reverse protection module includes a reverse protection diode D3. The reverse protection diode D3 can be a standard silicon diode, a Schottky diode, or similar.

[0092] In another implementation, in addition to using the reverse protection diode D3 to prevent reverse current from flowing into the power supply module, the power supply reverse protection module can also use other devices or circuits, such as power path management circuits (integrating MOSFET driving, charge pump, voltage detection, fault protection and other functions to achieve high-performance power path management), dual MOSFET back-to-back structure (bidirectional controllable), etc.

[0093] Thus, the technical solution of this embodiment can also be to implement the power supply reverse protection function.

[0094] In one embodiment, the power supply protection circuit provided in this embodiment may further include a voltage regulator module, which is connected to the power output terminal Vout and configured to stabilize the power output of the power output terminal Vout.

[0095] In one implementation, see [reference] Figure 8 The voltage regulator module includes a voltage regulator capacitor C1.

[0096] In another implementation, in addition to using the anti-reverse diode D3 to stabilize the power output at the power output terminal Vout, the voltage regulator module can also use other devices or circuits, such as LC filters (inductor-capacitor combination), linear regulators, etc.

[0097] For example, see Figure 8 This embodiment provides a power supply protection circuit, including: a power input terminal VBAT, a power output terminal Vout, a second transistor Q2 (i.e., the aforementioned current regulation module M1), a first resistor R1, a first transistor Q1, a third transistor Q3 and a second resistor R2 (i.e., the aforementioned device protection module), a Zener diode D1 (i.e., the aforementioned first voltage clamping module), a transient voltage suppression diode D2 (i.e., the aforementioned second voltage clamping module), a reverse protection diode D3 (i.e., the aforementioned power supply reverse protection module), and a Zener capacitor C1 (i.e., the aforementioned voltage regulation module); wherein, the second transistor Q2 and the third transistor Q3 are both PNP transistors, and the first transistor Q1 is an NPN transistor; Among them, the power input terminal VBAT is used to connect the power module to receive power current and power voltage; Among them, the power output terminal Vout is used to connect to the power module to supply power to the power module; Among them, the first end of the first resistor R1 is connected to the power input terminal VBAT through the anti-reverse diode D3, the second end of the first resistor R1 is connected to the emitter of the third transistor Q3, and is connected to the base of the first transistor Q1 through the collector of the third transistor Q3. Among them, the base of the first transistor Q1 is also grounded through the Zener diode D1, the collector of the first transistor Q1 is connected to the power input terminal VBAT, the emitter of the first transistor Q1 is connected to the power output terminal Vout, and the emitter of the first transistor Q1 and the power output terminal Vout are also grounded through the Zener capacitor C1. The base of the second transistor Q2 is connected between the second end of the first resistor R1 and the emitter of the third transistor Q3. The emitter of the second transistor Q2 is connected to the first end of the first resistor R1. The collector of the second transistor Q2 is grounded through the second resistor R2. The base of the third transistor Q3 is connected between the collector of the second transistor Q2 and the second resistor R2. The first terminal of the transient voltage suppression diode D2 is connected between the power input terminal VBAT and the first terminal of the first resistor R1, and the second terminal of the transient voltage suppression diode D2 is grounded.

[0098] Specifically, when the power module is supplying power normally, the voltage drop of the anti-reverse diode D3 is very small (negligible). When the power module is damaged or short-circuited, causing overcurrent, the current IQ2 flowing through the collector and emitter of the first transistor Q1 increases, which in turn causes the current IR1 flowing through the first resistor R1 to increase proportionally. The increase in the current IR1 flowing through the first resistor R1 leads to an increase in the voltage drop across the first resistor R1. Thus, the emitter voltage VE of the second transistor Q2 is equal to the power supply voltage Vbat of the power module (i.e., VE = Vbat), the base voltage VB of the second transistor Q2 is equal to the power supply voltage Vbat of the power module minus the voltage drop VR1 of the first resistor R1 (i.e., VB = Vbat - VR1), and the collector voltage VC of the second transistor Q2 is equal to the power supply voltage Vbat of the power module minus the voltage drop VR1 of the first resistor R1, plus the voltage drop from the emitter to the base of the second transistor Q2. (i.e., VC = Vbat - VR1 - Therefore, VE is greater than VB and VB is greater than VC, causing the second transistor Q2 to switch from the cutoff state to the amplification region. Furthermore, the emitter voltage of the third transistor Q3 is VE, and the base voltage VB of the third transistor Q3 is equal to the emitter voltage VE of the third transistor Q3 minus the forward voltage drop V1 between the emitter and base of the third transistor Q3Q1 (i.e., VB = VE - V1). The collector voltage VC of the third transistor Q3 is equal to the emitter voltage VE of the third transistor Q3Q1 minus the forward voltage drop V2 of the third transistor Q3 (i.e., VB = VE - V2, V2 is less than V1). Therefore, VE of the third transistor Q3 is greater than VB and VC is greater than VB, causing the third transistor Q3 to be in the saturation region. Additionally, the collector voltage VC of the first transistor Q1 is equal to the power supply voltage Vbat of the power module minus the voltage drop VD1 of the anti-reverse diode D3 (i.e., VC = Vbat - VD1). VD1), the base voltage VB of the first transistor Q1 is equal to the power supply voltage Vbat of the power module minus the voltage drop VD1 of the anti-reverse diode D3, minus the voltage drop VR1 of the first resistor R1 and the on-state voltage drop from the emitter to the collector of the third transistor Q3. (i.e., VB = Vbat - VD1 - VR1 -) Therefore, VC is greater than VB, causing the first transistor Q1 to be in the amplification region; at this time, the maximum voltage across the first resistor R1 is... Equal to the saturation voltage drop from the emitter to the collector of transistor Q2 Therefore, the maximum current flowing through the first resistor R1 The calculation formula is: ,in, This indicates the resistance value of the first resistor R1; the maximum supply current that the emitter of the first transistor Q1 can output. The calculation formula is: ,in, This indicates the amplification factor in the device characteristics of the first transistor Q1.

[0099] The maximum supply current that the emitter of the first transistor Q1 can output can be designed according to the current requirements of the power supply module. Adjusting the maximum supply current output by the emitters of the first transistors Q1 and Q2 can be achieved by selecting at least one of the following: the resistance of the first resistor R1, the second transistor Q2, and the first transistor Q1. For example, if the power supply module requires 1A of current, the hardware will be designed with a current limit of 1.2A (usually with a 20% current limit). The specific calculation of the maximum supply current output by the emitter of the first transistor Q1 is related to the components of the power supply protection circuit, but the core component to select is the first resistor R1. Specific calculation rules can refer to the maximum current flowing through the first resistor R1. The calculation formula and the maximum supply current that the emitter of the first transistor Q1 can output. The calculation formula is as follows: Alternatively, a simpler calculation method is: if the power module requires a current demand of I1 (e.g., I1 = 1A), then the design current I2 of the base of the first transistor Q1 can be I1 divided by the amplification factor of the first transistor Q1, and the resistance value of the first resistor R1 is selected as 0.7V divided by the design current I2. Thus, the technical solution of this embodiment can, when configuring the power supply protection circuit, calculate the maximum operating current of the power module and the maximum tolerable current of its hardware, and set a reasonable current limit value to correspond to the model of all or part of the components in the power supply protection circuit, thereby enabling the power supply protection circuit to achieve the function of current limiting output (i.e., overcurrent protection function).

[0100] Understandably, when the power module is supplying power normally and the second transistor Q2 is in the off state (corresponding to the normal operation of the power module), the third transistor Q3 is in the saturation region and the first transistor Q1 is in the amplification region. The supply current output to the power output terminal Vout through the first transistor Q1 is adjusted according to the load change of the power module within the preset safe current. The supply voltage output to the power output terminal Vout through the first transistor Q1 is adjusted according to the voltage change of the power input terminal VBAT.

[0101] When the power module is supplying power normally, the current flowing through the first resistor R1 is small, the voltage difference across the first resistor R1 is very small, and the emitter-junction voltage difference of the second transistor Q2 is very small (much smaller than the conduction voltage of the second transistor Q2, for example, 0.7V), which does not meet the conduction condition of the second transistor Q2. Therefore, the second transistor Q2 is in the off state. At this time, the emitter junction of the third transistor Q3 is forward biased, and with the help of the second resistor R2, the third transistor Q3 is in the saturation region (for example, the voltage difference between the collector and emitter of the third transistor Q3 is about 0.3V). In addition, The first resistor R1 can be configured to forward bias the emitter junction of the first transistor Q1, thus placing the first transistor Q1 in the amplification region. Specifically, the collector voltage VC of the first transistor Q1 is equal to the power supply voltage Vbat of the power module minus the voltage drop VD1 of the reverse protection diode D3 (i.e., VC = Vbat - VD1), and the base voltage VB of the first transistor Q1 is equal to the power supply voltage Vbat of the power module minus the voltage drop VD1 of the reverse protection diode D3, the voltage drop VR1 of the first resistor R1, and the on-state voltage drop from the emitter to the collector of the third transistor Q3. (i.e., VB = Vbat - VD1 - VR1 - ...) Therefore, VC is greater than VB, which puts the first transistor Q1 in the amplification region.

[0102] Understandably, when the power module is supplying power normally and the power demand of the power-consuming module is within the preset safe current range, the second transistor Q2 and the Zener diode D1 have no effect. The third transistor Q3 is in the saturation region, and the first transistor Q1 is in the amplification region. As long as the power-consuming module does not experience overcurrent (i.e., when the second transistor Q2 does not switch to the amplification region), the first transistor Q1 can output any current value less than the preset safe current based on the load demand of the power-consuming module. Therefore, when the power module is supplying power normally, the output current capability of the power supply protection circuit can be dynamically adjusted according to load changes.

[0103] Understandably, when the power module is supplying power normally, the power supply voltage of the power module increases, the cathode voltage of the reverse protection diode D3 increases accordingly, and the voltage across the first resistor R1 also increases, resulting in an increase in the current flowing through the first resistor R1. This reduces the collector-emitter voltage drop of the first transistor Q1, thereby increasing the supply voltage of the first transistor Q1. Conversely, when the power module is supplying power normally, the power supply voltage of the power module decreases, the cathode voltage of the reverse protection diode D3 decreases accordingly, and the voltage across the first resistor R1 also decreases, resulting in a decrease in the current flowing through the first resistor R1. This increases the collector-emitter voltage drop of the first transistor Q1, thereby decreasing the output voltage of the first transistor Q1. Therefore, when the power module is supplying power normally, the supply voltage of the power supply protection circuit changes with the power supply voltage of the power module. Taking the power supply to the controller in a vehicle as an example, when the power supply voltage of the power module is between 5 and 32V, the supply voltage changes synchronously with the input power supply voltage.

[0104] Understandably, the second resistor R2 can be used to limit the emitter-to-collector current of the second transistor Q2 and the emitter-to-base current of the third transistor Q3.

[0105] Understandably, the second transistor Q2 can be called a current-controlled transistor. When the current flowing through the first resistor R1 reaches the turn-on voltage of the third transistor Q3, the third transistor Q3 turns on. The first resistor R1 can be called a current-limiting output regulating resistor.

[0106] Understandably, the third transistor Q3 plays an isolation role in implementing the overcurrent protection function to prevent the second transistor Q2 from being damaged by a large current.

[0107] Understandably, when the first transistor Q1 is operating in the amplification region, it is used to clamp the supply voltage and limit the supply current.

[0108] Understandably, when the power module throws a load, the cathode of the reverse protection diode D3 will have a high transient voltage (i.e., the first voltage) due to the presence of the transient voltage suppressor diode D2. This transient voltage is applied to the Zener diode D1 through the first resistor R1 and the third transistor Q3. The Zener diode D1 clamps this transient voltage to a preset safe voltage. Thus, the base of the first transistor Q1 is at the preset safe voltage, and the emitter of the first transistor Q1 outputs a supply voltage lower than the preset safe voltage. Therefore, because the Zener diode D1 and the transient voltage suppressor diode D2 work together to precisely adjust the output voltage, the voltage withstand requirement of the power module can be reduced. Furthermore, the reduced voltage withstand requirement also lowers the cost. Taking a preset safe voltage of 32V as an example, the supply voltage output from the emitter of the first transistor Q1 is: ,in, This represents the voltage drop from the base to the emitter of the first transistor Q1. This indicates the voltage at the cathode of the anti-reverse diode D3.

[0109] Based on the same inventive concept as the foregoing embodiments, this application also provides a vehicle, including a power module, a controller, and a power supply protection circuit described in any of the first to sixth embodiments above; the controller is connected to the power module through the power supply protection circuit. Thus, the power supply protection circuit in the vehicle provided by this embodiment can simultaneously meet the dual requirements of overcurrent protection and continuous power supply, thereby improving power supply protection performance.

[0110] In some implementations, the vehicle may be construction machinery, agricultural machinery, or automated guided vehicles, etc. From the perspective of power type, the vehicle may be a fuel engine vehicle or a new energy vehicle, such as a hybrid vehicle, etc., without specific limitations here.

[0111] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0112] In this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0113] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power supply protection circuit, characterized in that, Includes a power input terminal, a power output terminal, a current regulation module, a first resistor, and a first transistor; The first end of the first resistor is connected to the power input terminal, the second end of the first resistor is connected to the base of the first transistor, the first terminal of the first transistor is connected to the power input terminal, and the second terminal of the first transistor is connected to the power output terminal. The first terminal and the second terminal are respectively one of the collector and the emitter. The current regulation module is connected in parallel to the first and second ends of the first resistor and is configured to regulate the current flowing through the first resistor and the base of the first transistor by limiting the voltage across the first resistor, so as to limit the current at the second terminal of the first transistor operating in the amplification region.

2. The power supply protection circuit according to claim 1, characterized in that, The current regulation module includes a second transistor, the emitter and base of which are respectively connected to the two ends of the first resistor, and the voltage across the first resistor is limited by the emitter junction of the second transistor.

3. The power supply protection circuit according to claim 2, characterized in that, The second transistor is a PNP transistor; The base of the second transistor is connected to the second end of the first resistor, the emitter of the second transistor is connected to the first end of the first resistor, and the collector of the second transistor is grounded.

4. The power supply protection circuit according to claim 3, characterized in that, The power supply protection circuit also includes a device protection module; The device protection module is connected to the second transistor and is configured to provide overcurrent protection for the second transistor.

5. The power supply protection circuit according to claim 4, characterized in that, The device protection module includes a third transistor and a second resistor, wherein the third transistor is a PNP transistor; The first end of the second resistor is connected to the collector of the second transistor, and the collector of the second transistor is grounded through the second resistor; The base of the third transistor is connected between the collector of the second transistor and the second resistor, the emitter of the third transistor is connected to the second end of the first resistor, and the collector of the second transistor is connected to the base of the first transistor.

6. The power supply protection circuit according to claim 1, characterized in that, The power supply protection circuit also includes a first voltage clamping module; The first voltage clamping module is connected to the base of the first transistor and is configured to reduce the voltage of the base of the first transistor to a preset safe voltage when the power module dumps a load, so that the power output terminal connected to the emitter of the first transistor outputs a supply voltage less than or equal to the preset safe voltage.

7. The power supply protection circuit according to claim 6, characterized in that, The first voltage clamping module is a Zener diode; The base of the first transistor is grounded through the Zener diode.

8. The power supply protection circuit according to any one of claims 1 to 7, characterized in that, The power supply protection circuit also includes at least one of the following: The second voltage clamping module is connected between the first end of the first resistor and the power input terminal, and is configured to reduce the increased voltage when the power module dumps the load, and transmit the reduced voltage to the first resistor. A reverse current protection module is connected between the first end of the first resistor and the power input terminal and is configured to prevent reverse current from flowing into the power module. A voltage regulator module is connected to the power output terminal and is configured to stabilize the power output of the power output terminal.

9. The power supply protection circuit according to claim 8, characterized in that, The second voltage clamping module includes a transient voltage suppression diode; The power supply anti-reverse module includes an anti-reverse diode; The voltage regulator module includes a voltage regulator capacitor.

10. A vehicle, characterized in that, Includes a power module, a controller, and a power supply protection circuit as described in any one of claims 1 to 9; The controller is connected to the power module through the power supply protection circuit.

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