Power supply circuit, electrical device, and vehicle

Abstract

A power supply circuit, an electrical device, and a vehicle. The power supply circuit (100) comprises: a voltage-stabilized power supply (10) used for converting a first voltage provided by an external power supply into a second voltage; and an enabling unit (20) used for outputting a first enable signal on the basis of the first voltage when the external power supply starts to provide the first voltage, so that the voltage-stabilized power supply (10) starts to work, and outputting a protection signal on the basis of the second voltage when the voltage-stabilized power supply (10) outputs the second voltage and the second voltage is less than or equal to a preset voltage threshold, so that the voltage-stabilized power supply (10) stops working and is in a protected state.

Description

Power circuits, electrical equipment and vehicles

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese patent application number 202410262697.3, filed on March 7, 2024, entitled “POWER CIRCUIT, ELECTRICAL EQUIPMENT AND VEHICLE,” the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the field of vehicle technology, and in particular to a power supply circuit, an electrical device, and a vehicle. Background Art

[0004] When the output end of the regulated power supply is short-circuited or the impedance becomes abnormally small, the load current of the regulated power supply will exceed the maximum output current of the regulated power supply, and the output voltage of the regulated power supply will be pulled down, which is not conducive to the normal operation of the regulated power supply.

[0005] Related technologies achieve short-circuit protection for regulated power supplies by adding a short-circuit protection circuit. Specifically, the short-circuit protection circuit detects the load current and, if it determines that the load current exceeds the maximum output current, shuts down the regulated power supply, causing it to stop outputting voltage. However, this solution is relatively complex, increasing application costs.

[0006] Public content

[0007] The present disclosure aims to solve one of the technical problems in the related art at least to a certain extent. To this end, the first object of the present disclosure is to provide a power supply circuit.

[0008] The second objective of the present disclosure is to provide an electrical device.

[0009] A third object of the present disclosure is to provide a vehicle.

[0010] To achieve the above-mentioned objectives, an embodiment of the first aspect of the present disclosure proposes a power supply circuit, comprising: a voltage-stabilized power supply, the input end of the voltage-stabilized power supply being suitable for being connected to an external power supply, for converting a first voltage provided by the external power supply into a second voltage; an enabling unit, the input end of the enabling unit being suitable for being connected to the external power supply, the input end of the enabling unit being connected to the output end of the voltage-stabilized power supply, the output end of the enabling unit being connected to the enabling end of the voltage-stabilized power supply, for outputting a first enabling signal based on the first voltage when the external power supply starts to provide a first voltage, so that the voltage-stabilized power supply starts working, and for outputting a protection signal based on the second voltage when the voltage-stabilized power supply outputs a second voltage and the second voltage is less than or equal to a preset voltage threshold, so that the voltage-stabilized power supply stops working and is in a protection state.

[0011] In addition, the power supply circuit according to the above embodiment of the present disclosure may also have the following additional technical features:

[0012] According to one embodiment of the present disclosure, the enabling unit is further configured to output a second enabling signal based on the second voltage when the regulated power supply outputs a second voltage and the second voltage is greater than a preset voltage threshold, so as to keep the regulated power supply working.

[0013] According to one embodiment of the present disclosure, the enabling unit includes: a first capacitor, a first resistor, and a second resistor, one end of the first capacitor is suitable for being connected to an external power supply, the other end of the first capacitor, one end of the first resistor, and one end of the second resistor are respectively connected to the enabling end of the regulated power supply, the other end of the first resistor is grounded, and the other end of the second resistor is connected to the output end of the regulated power supply.

[0014] According to one embodiment of the present disclosure, the enabling unit further includes: a diode, wherein an anode of the diode is adapted to be connected to an external power supply, and a cathode of the diode is connected to one end of the first capacitor.

[0015] According to an embodiment of the present disclosure, the enabling unit further includes: a third resistor, which is connected in parallel with the first capacitor.

[0016] According to one embodiment of the present disclosure, the power supply circuit also includes: a reset unit, wherein the reset end of the reset unit is connected to the enable end of the regulated power supply, and is used to output a reset signal when the regulated power supply is in a protection state and meets a preset reset condition, so that the regulated power supply exits the protection state and starts working; wherein the preset reset condition includes the reset unit receiving an external reset control instruction or the reset unit determining that the time the regulated power supply is in the protection state reaches a preset time.

[0017] According to one embodiment of the present disclosure, the input end of the reset unit is connected to the enable end of the voltage-stabilized power supply, and is used to determine whether the duration of the voltage-stabilized power supply in the protection state reaches a preset duration based on the voltage of the enable end; or, the input end of the reset unit is connected to the output end of the voltage-stabilized power supply, and is used to determine whether the duration of the voltage-stabilized power supply in the protection state reaches a preset duration based on the second voltage; or, the input end of the reset unit is connected to the status output end of the voltage-stabilized power supply, and is used to determine whether the duration of the voltage-stabilized power supply in the protection state reaches a preset duration based on the status signal of the status output end, wherein the feedback end of the voltage-stabilized power supply is connected to the output end of the regulated voltage to obtain the second voltage and generate a status signal based on the second voltage.

[0018] According to one embodiment of the present disclosure, the power supply circuit further includes: a second capacitor connected in series between the input terminal of the voltage-stabilized power supply and the ground.

[0019] According to one embodiment of the present disclosure, the power supply circuit further includes: a third capacitor connected in series between the output end of the voltage-stabilized power supply and the ground; and a fourth resistor connected in parallel with the third capacitor.

[0020] According to one embodiment of the present disclosure, the voltage-regulated power supply includes a linear voltage-regulated power supply, a switching voltage-regulated power supply, or a low voltage difference voltage-regulated power supply.

[0021] To achieve the above-mentioned objective, a second embodiment of the present disclosure provides an electrical device, comprising the above-mentioned power supply circuit.

[0022] To achieve the above-mentioned objectives, a third embodiment of the present disclosure provides a vehicle comprising the above-mentioned power supply circuit.

[0023] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0025] FIG1 is a connection diagram of a power supply circuit according to an embodiment of the present disclosure;

[0026] FIG2 is a circuit diagram 1 of a power supply circuit according to a specific embodiment of the present disclosure;

[0027] FIG3 is a schematic diagram 1 of a case where the first voltage is slowly reduced;

[0028] FIG4 is a schematic diagram 1 of a case where the first voltage decreases rapidly;

[0029] FIG5 is a second schematic diagram of a case where the first voltage decreases rapidly;

[0030] FIG6 is a partial circuit diagram of an enabling unit according to a specific embodiment of the present disclosure;

[0031] FIG7 is a connection diagram of a power supply circuit according to an embodiment of the present disclosure;

[0032] FIG8 is an equivalent circuit diagram of FIG2 when only the external power supply is used and there is no second voltage;

[0033] FIG9 is an equivalent circuit diagram of the enabling unit in FIG8 ;

[0034] FIG10 is a schematic diagram of the output characteristics of FIG8;

[0035] FIG11 is an equivalent circuit diagram of FIG2 when only the second voltage is input without the first voltage;

[0036] FIG12 is an equivalent circuit diagram of the enabling unit in FIG11 ;

[0037] FIG13 is a schematic diagram of the output characteristics of FIG11;

[0038] FIG14 is a schematic diagram of output characteristics after FIG10 and FIG13 are superimposed;

[0039] FIG15 is a schematic diagram of a simulation according to a specific embodiment of the present disclosure;

[0040] FIG16 is a schematic diagram of a simulation according to another specific embodiment of the present disclosure;

[0041] FIG17 is a block diagram of an electrical device according to an embodiment of the present disclosure;

[0042] FIG18 is a block diagram of a vehicle according to an embodiment of the present disclosure. Modes for Carrying Out the Invention

[0043] The following describes in detail embodiments of the present disclosure, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and should not be construed as limiting the present disclosure.

[0044] The power supply circuit, electrical equipment, and vehicle proposed in the embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0045] When a short circuit occurs at the output of a regulated power supply, or when the impedance decreases abnormally, the load current will exceed the maximum output current of the regulated power supply, causing the output voltage to drop until the load current equals the maximum output current. Some regulated power supplies have short-circuit protection, which automatically shuts down the regulated power supply and stops outputting voltage when the load current exceeds the maximum output current. However, this short-circuit protection circuit is relatively complex and requires active devices such as transistors or MOS (Metal-Oxide-Semiconductor) tubes. Some also require sampling resistors, and some may repeatedly restart.

[0046] In order to solve at least one of the above-mentioned technical problems, the present application proposes a power supply circuit. When an external power supply starts to provide a first voltage, an enabling unit outputs a first enabling signal based on the first voltage to enable the regulated power supply to start working, and when the regulated power supply outputs a second voltage and the second voltage is less than or equal to a preset voltage threshold, a protection signal is output based on the second voltage to enable the regulated power supply to stop working and be in a protection state, thereby reducing the failure degree of the circuit and eliminating the need to add an additional short-circuit protection circuit, thereby reducing the application cost.

[0047] FIG1 is a connection diagram of a power supply circuit according to an embodiment of the present disclosure.

[0048] As shown in FIG1 , the power supply circuit 100 according to the embodiment of the present disclosure includes a voltage-stabilized power supply 10 and an enabling unit 20 .

[0049] The input terminal VIN of the voltage-regulated power supply 10 is adapted to be connected to an external power supply, and the voltage-regulated power supply 10 is configured to convert a first voltage Vin provided by the external power supply into a second voltage Vout. The input terminal of the enabling unit 20 is adapted to be connected to the external power supply, the input terminal of the enabling unit 20 is connected to the output terminal VOUT of the voltage-regulated power supply 10, and the output terminal of the enabling unit 20 is connected to the enable terminal EN of the voltage-regulated power supply 10. The enabling unit 20 is configured to output a first enable signal based on the first voltage Vin when the external power supply begins to provide the first voltage Vin, thereby enabling the voltage-regulated power supply 10 to start operating, and to output a protection signal based on the second voltage Vout when the voltage-regulated power supply 10 outputs the second voltage Vout and the second voltage Vout is less than or equal to a preset voltage threshold, thereby enabling the voltage-regulated power supply 10 to stop operating and enter a protection state.

[0050] Specifically, when the external power supply starts to provide the first voltage Vin, the circuit provides the first voltage Vin to the input terminal VIN of the regulated power supply 10 on the one hand, and provides it to the enabling unit 20 on the other hand. The enabling unit 20 outputs a first enabling signal based on the first voltage Vin. After receiving the first enabling signal, the enabling terminal EN of the regulated power supply 10 controls the regulated power supply 10 to start, and the regulated power supply 10 starts to work to convert the first voltage Vin provided by the external power supply into the second voltage Vout.

[0051] When the regulated power supply 10 begins operation and converts a first voltage Vin provided by an external power source into a second voltage Vout for output, the enabling unit 20 receives the second voltage Vout through an input terminal. When the second voltage Vout is less than or equal to a preset voltage threshold, the enabling unit 10 outputs a protection signal based on the second voltage Vout, thereby causing the regulated power supply 10 to cease operation and enter a protection state. For example, if a fault short circuit occurs on the output side of the regulated power supply 10, and the output voltage of the regulated power supply 10, i.e., the second voltage Vout, is pulled low due to an overload, the enabling unit 20 determines that the regulated power supply 10 may be overloaded when the second voltage Vout is less than or equal to the preset voltage threshold, and then outputs a protection signal based on the second voltage Vout, thereby causing the regulated power supply 10 to cease operation and enter a protection state.

[0052] It is understood that if the second voltage Vout output by the voltage-stabilized power supply 10 is 0 after it stops working, then the second voltage Vout remains below the preset voltage threshold, and the enabling unit 10 maintains the continuous output of the protection signal, thereby forming a closed-loop shutdown control, ensuring that the voltage-stabilized power supply 10 in the protection state is always in the stopped state, avoiding repeated restarts. Exiting the protection state can be achieved based on an external restart signal, which is not limited here.

[0053] Therefore, this embodiment can enable the enabling unit 20 to output a protection signal to the enable terminal EN of the regulated power supply 10 based on the second voltage when the second voltage Vout output by the regulated power supply is less than or equal to the preset voltage threshold, so as to control the regulated power supply 10 to stop working and enter the protection state, thereby realizing the load short-circuit protection function of the regulated power supply 10, and automatically shutting down the regulated power supply 10 when the output of the regulated power supply 10 is short-circuited or abnormally overloaded, reducing the failure degree of the circuit, and eliminating the need to add an additional short-circuit protection circuit, thereby reducing the application cost.

[0054] It should be noted that the regulated power supply 10 can be a linear regulated power supply, a switching regulated power supply (non-isolated, input and output in-phase topology such as BUCK, BOOST), a low voltage dropout regulated power supply (LDO), etc., and is not limited here.

[0055] In one embodiment of the present disclosure, the enabling unit 20 is further configured to output a second enabling signal based on the second voltage Vout when the regulated power supply 10 outputs the second voltage Vout and the second voltage Vout is greater than a preset voltage threshold, so as to keep the regulated power supply 10 working.

[0056] That is, when the regulated power supply 10 starts operating, i.e., converts the first voltage Vin into the second voltage Vout for output, the enabling unit 20 enables the regulated power supply 10 based on the second voltage Vout. Specifically, when the second voltage Vout is greater than a preset voltage threshold, the enabling unit 20 outputs a second enabling signal based on the second voltage Vout, so that the regulated power supply 10 continues to operate based on the second enabling signal. When the second voltage Vout is less than or equal to the preset voltage threshold, the enabling unit 10 outputs a protection signal based on the second voltage Vout, so that the regulated power supply 10 stops operating and enters a protection state.

[0057] In this embodiment, when the external power supply starts to provide the first voltage Vin, the regulated power supply 10 is enabled and controlled based on the first voltage Vin, and is not affected by the output voltage of the regulated power supply 10, wherein the enabling control includes controlling the regulated power supply 10 to start working; when the regulated power supply 10 starts to work and outputs the second voltage Vout, the regulated power supply 10 is enabled and controlled based on the second voltage Vout, and is not affected by the first voltage Vin received at the input end, wherein the enabling control includes continuing to work and stopping working and entering a protection state.

[0058] As shown in Figure 2, in one embodiment of the present disclosure, the enabling unit 20 includes: a first capacitor C1, a first resistor R1, and a second resistor R2. One end of the first capacitor C1 is suitable for connecting to an external power supply, and the other end of the first capacitor C1, one end of the first resistor R1, and one end of the second resistor R2 are respectively connected to the enable end EN of the regulated power supply 10. The other end of the first resistor R1 is grounded, and the other end of the second resistor R2 is connected to the output end VOUT of the regulated power supply 10.

[0059] Specifically, during initial power-on, that is, when the external power supply starts to provide the first voltage Vin, the step change of the input voltage of the power supply circuit 100 will automatically generate a pulse voltage, namely the first enable signal, at the enable terminal EN of the regulated power supply 10 through the first capacitor C1 and the first resistor R1, so that the regulated power supply 10 can be automatically started only by passive components without the need for additional control.

[0060] When the regulated power supply 10 is in a steady state, the voltage at the enable terminal EN of the regulated power supply 10 is generated by dividing the output terminal VOUT through the second resistor R2 and the first resistor R1. When the output terminal VOUT is abnormally overloaded, that is, the second voltage Vout is less than or equal to the preset voltage threshold, the voltage at the enable terminal EN is automatically pulled down to the enable threshold to control the regulated power supply 10 to stop working, thereby protecting the circuit.

[0061] Therefore, this embodiment can realize power-on self-starting of the voltage-stabilized power supply 10 under normal load conditions and automatic protection under abnormal load conditions by reasonably selecting and setting the first resistor R1, the second resistor R2, and the first capacitor C1, and the circuit is simple and reliable to implement without additional control.

[0062] It should be noted that, during the design process of the power supply circuit 100, the values ​​of the first resistor R1, the second resistor R2, and the first capacitor C1 need to be determined based on actual circuit requirements. The values ​​of the first resistor R1, the second resistor R2, and the first capacitor C1 must meet the following conditions:

[0063] 1. Ensure that the first resistor R1 and first capacitor C1 circuit can generate a pulse of sufficient amplitude and width at the enable terminal EN when the external power supply starts to provide the first voltage Vin. If the first voltage Vin is not a constant value (for example, a battery), consider that a pulse sufficient to enable the regulated power supply 10 can also be generated at its lower limit voltage;

[0064] Second, the pulse width generated by the first resistor R1 and the first capacitor C1 cannot be too large. This is to prevent the pulse generated by the first resistor R1 and the first capacitor C1 from still being in the enabled startup state of the regulated power supply 10 when the abnormal (overload) state is started, so that the circuit can enter the protection state as soon as possible.

[0065] 3. Ensure that the output voltage after being divided by the second resistor R2 and the first resistor R1 is sufficient to enable the voltage-stabilized power supply 10. If the second voltage Vout is not a constant value, it is necessary to consider that a voltage sufficient to enable the circuit can be generated at its lower limit voltage.

[0066] Fourth, to ensure the normal short-circuit protection function, when the load of the power supply circuit is too large but no short circuit is formed, the voltage divided by the second resistor R2 and the first resistor R1 cannot reach the enabling threshold, that is, the enabling unit 20 outputs a protection signal before the short circuit occurs, so that the regulated power supply 10 stops working in advance and enters the protection state.

[0067] In this embodiment, when the external power supply is powered on / initialized, a pulse voltage, i.e., a first enable signal, can be automatically generated based on the first capacitor C1 and the first resistor R1 to enable the power supply circuit 10. This is achieved only by passive circuits, and the circuit implementation is simple, low-cost, and does not require additional control or software coordination. At the same time, when the regulated power supply 10 is in a steady state, i.e., when the output second voltage Vout is greater than a preset voltage threshold, the enabling unit 20 divides the second voltage Vout by the first resistor R1 and the second resistor R2 to generate a second enable signal to continuously enable the regulated power supply 10, ensuring that the regulated power supply 10 continues to work, and when the second voltage Vout is abnormal, i.e., when the second voltage Vout drops to a preset voltage threshold, a protection signal with a lower voltage is output to cause the regulated power supply 10 to lose its enable and automatically shut down, thereby protecting the regulated power supply 10 from continuing to work or repeatedly restarting in an abnormal state, avoiding heating or further damage to the circuit, and reducing the degree of circuit failure.

[0068] In addition, when the second voltage Vout of the circuit drops to a preset voltage threshold, the voltage-stabilized power supply 10 will lose its enable and automatically shut down, which can protect the front-stage circuit from being overloaded due to abnormalities in the subsequent-stage circuit. For example, the power supply system contains two-stage power supplies, power supply circuit 1 and power supply circuit 2, and the output of power supply circuit 1 is the input of power supply circuit 2. If power supply circuit 2 has no protection function, then when the load is short-circuited, power supply circuit 2 may pull down the output of power supply circuit 1 or even the input of power supply circuit 1. Based on the technical solution of the present application, power supply circuit 2 can automatically shut down and stop working when a short circuit occurs, so that the output of power supply circuit 1 can still remain normal and will not affect the circuit supplied by power supply circuit 1, thereby greatly reducing the circuit failure area.

[0069] However, if the input voltage of the power supply circuit 100, that is, the first voltage Vin, is unstable, for example, when the first voltage Vin slowly decreases and the voltage of the second voltage Vout output by the voltage-stabilized power supply 10 is stable, as shown in Figure 3, the enable voltage Ven can basically remain stable; when the first voltage Vin suddenly decreases rapidly in a negative direction and the first voltage Vin produces a large amplitude fluctuation, the voltage on the first capacitor C1 will decrease rapidly, and a certain discharge current (iC=C*dvC / dt) will be generated on the first capacitor C1, and the enable voltage Ven will drop negatively. If the voltage Ven does not drop below the enable threshold, as shown in Figure 4, the voltage-stabilized power supply 10 will continue to work. If the voltage Ven drops below the enable threshold, as shown in Figure 5, the voltage-stabilized power supply 10 will stop working, the second voltage Vout will stop being output, and the voltage Ven will also drop to 0.

[0070] To avoid the above problems, the present application further optimizes the circuit. As shown in Figure 6, in one embodiment of the present disclosure, the enabling unit 20 also includes: a diode D1, the anode of the diode D1 is suitable for being connected to an external power supply, and the cathode of the diode D1 is connected to one end of the first capacitor C1.

[0071] This embodiment connects a diode D1 in series at the front end of the first capacitor C1 to limit the current flow. Therefore, when the first voltage Vin drops rapidly, the diode D1 can prevent the drop of the first voltage Vin from affecting the voltage of the enable pin EN.

[0072] In one embodiment of the present disclosure, the enabling unit 20 further includes: a third resistor R3 , which is connected in parallel with the first capacitor C1 .

[0073] Specifically, when the first voltage Vin undergoes a negative sudden change, the voltage at the cathode of the diode D1 does not suddenly change but slowly decreases. The speed of decrease depends on the value of the third resistor R3. The smaller the resistance of the third resistor R3, the faster the voltage at the cathode of the diode D1 decreases, thereby accelerating the discharge speed of the capacitor C1.

[0074] After the voltage-stabilized power supply 10 is in the protection state, the power supply circuit 100 cannot automatically reset and restart, and manual control is required, for example, by controlling the re-output of the first voltage Vin to control the reset and restart of the voltage-stabilized power supply 10. To achieve automatic reset of the voltage-stabilized power supply 10, as shown in FIG7 , in one embodiment of the present disclosure, the power supply circuit 100 further includes: a reset unit 30, wherein the reset terminal of the reset unit 30 is connected to the enable terminal EN of the voltage-stabilized power supply 10, and is configured to output a reset signal when the voltage-stabilized power supply 10 is in the protection state and a preset reset condition is met, so that the voltage-stabilized power supply 10 exits the protection state and begins operation; wherein the preset reset condition includes the reset unit 30 receiving an external reset control instruction or the reset unit 30 determining that the voltage-stabilized power supply 10 has been in the protection state for a preset time period.

[0075] Specifically, the enable end of the regulated power supply 30 is connected to the reset unit 30. When the reset unit 30 receives an external reset control instruction when the regulated power supply 10 is in the protection state, it can output a reset signal such as a high-level signal through the reset end, or output a reset signal when it is determined that the time when the regulated power supply 10 is in the protection state reaches a preset time.

[0076] The regulated power supply 10 restarts working based on the received reset signal and converts the first voltage Vin into a second voltage Vout for output. The enabling unit 20 can generate a second enabling signal when the second voltage Vout is greater than a preset voltage threshold to keep the regulated power supply 10 working.

[0077] In this embodiment, by connecting the reset unit 30, the voltage-stabilized power supply 10 can be re-enabled by the reset unit 30 after the protection occurs, without the need to re-power the power supply circuit 100. It should be noted that the reset unit 30 can be an external controller.

[0078] In one embodiment of the present disclosure, the input end of the reset unit 30 is connected to the enable end of the regulated power supply 10, and is used to determine whether the duration of the regulated power supply 10 in the protection state reaches a preset duration based on the voltage of the enable end; or, the input end of the reset unit 30 is connected to the output end of the regulated power supply 10, and is used to determine whether the duration of the regulated power supply 10 in the protection state reaches a preset duration based on the second voltage Vout; or, the input end of the reset unit 30 is connected to the state output end of the regulated power supply 10, and is used to determine whether the duration of the regulated power supply 10 in the protection state reaches a preset duration based on the state signal of the state output end, wherein the feedback end of the regulated power supply 10 is connected to the output end of the regulated voltage to obtain the second voltage Vout, and generate a state signal based on the second voltage Vout.

[0079] That is to say, in one embodiment of the present application, the reset unit 30 determines whether the regulated power supply 10 enters the protection state based on the enable voltage Ven. Specifically, the input end (AD (Analog-Digital) port) of the reset unit can be directly connected to the enable end EN of the regulated power supply 10 to obtain the enable voltage Ven (the voltage of the enable end EN). When the enable voltage Ven is less than or equal to the first preset voltage, it is determined that the regulated power supply 10 enters the protection state and starts timing. When the timing time reaches the preset protection time, the reset signal is output.

[0080] In another embodiment of the present application, the reset unit 30 determines whether the regulated power supply 10 enters the protection state based on the second voltage Vout. Specifically, the input end (AD port) of the reset unit can be connected to the output end VOUT of the regulated power supply 10 through a sampling circuit. The sampling circuit can be a voltage divider circuit composed of resistors, which divides the second voltage Vout and outputs the sampled voltage to the input end. When the reset unit determines that the second voltage Vout is less than or equal to a preset voltage threshold based on the sampling voltage, it considers that the regulated power supply 10 enters the protection state and starts timing. When the timing time reaches the preset protection time, the reset signal is output.

[0081] In another embodiment of the present application, the reset unit 30 determines whether the regulated power supply 10 has entered a protection state based on a status signal output by the regulated power supply 10. Specifically, the regulated power supply 10 determines the corresponding status signal based on its own status detection program. For example, when the second voltage Vout is less than or equal to a preset voltage threshold, the reset unit 30 outputs a high-level signal, i.e., a first status signal; when the second voltage Vout is greater than the preset voltage threshold, the reset unit 30 outputs a low-level signal, i.e., a second status signal. Upon receiving the first status signal, the reset unit 30's third input terminal (IO (Input / Output) port) determines that the regulated power supply 10 has entered a protection state and begins timing. When the timing reaches a preset duration, the reset unit 30 outputs a reset signal.

[0082] In one embodiment of the present disclosure, as shown in Figure 2, the power supply circuit 100 further includes a second capacitor C2 connected in series between the input terminal VIN and the ground of the voltage-stabilized power supply 10. Thus, the first voltage Vin is filtered and outputted through the second capacitor C1.

[0083] In one embodiment of the present disclosure, the power supply circuit 100 further includes a third capacitor C3 connected in series between the output terminal VOUT of the regulated power supply 10 and ground; and a fourth resistor R4 connected in parallel with the third capacitor C3. Thus, the third capacitor C3 and the fourth resistor R4 constitute a filtering unit to filter and output the second voltage Vout.

[0084] As a specific embodiment of the present application, the power supply circuit 100 is shown in FIG2 .

[0085] When only the first voltage Vin exists in the circuit and the second voltage Vout does not, the equivalent circuit is shown in Figures 8 and 9 , and the voltage output characteristic of the enable terminal EN is shown in Figure 10 , where Ven is the voltage at the enable terminal EN and Vin is the first voltage. Under certain resistance and capacitance parameters, the output characteristic of Ven is a pulse lasting approximately ten milliseconds.

[0086] When power supply circuit 100 only has the second voltage Vout and no first voltage Vin, the equivalent circuit is shown in Figures 11 and 12, where C1' represents the series connection of the first capacitor C1 and the impedance of the input terminal VIN to GND. The voltage output characteristics of the enable terminal EN are shown in Figure 13, where Ven is the voltage at the enable terminal EN and Vout is the second voltage. Furthermore, under certain resistance and capacitance parameters, the output characteristics of Ven are characterized by a rise time of tens of milliseconds and a steady-state value approximately half that of Vout.

[0087] According to the superposition theorem, the voltage output characteristic of the enable terminal EN is the superposition of the above two output characteristics, as shown in Figure 14, where V is the superposition of the first voltage Vin and the second voltage Vout, and Ven is the voltage of the enable terminal EN.

[0088] When the regulated power supply 10 starts normally, due to the action of the first resistor R1 and the first capacitor C1, the input of the first voltage Vin generates a pulse voltage at the enable terminal EN. This voltage enables the regulated power supply 10 normally, and the regulated power supply 10 establishes an output voltage, namely, the second voltage Vout. After the second voltage Vout is established, due to the action of the second resistor R2 and the first resistor R1, the second voltage Vout forms a voltage divider at the enable terminal EN. When the second voltage Vout is greater than the preset voltage threshold, this voltage can continue to enable the regulated power supply 10, allowing the regulated power supply 10 to operate normally and output voltage.

[0089] When an output short circuit occurs in the regulated power supply 10 during operation, the second voltage Vout will be pulled down due to the increase in load current. At this time, the voltage level of the second voltage Vout at the enable terminal EN through R2 and R1 will also decrease. When the voltage at the enable terminal EN is insufficient to enable the regulated power supply 10, that is, when the second voltage Vout is less than or equal to the preset power threshold, the regulated power supply 10 stops outputting and will not restart repeatedly.

[0090] When the voltage-stabilized power supply re-inputs the input voltage in the state of output short circuit, due to the action of the first resistor R1 and the first capacitor C1, the input of the first voltage Vin will also generate a pulse voltage on the enable terminal EN, so that the voltage-stabilized power supply 10 is temporarily enabled. However, due to the output short circuit, the output voltage cannot be established. When the first capacitor C1 is fully charged, there is no voltage on the enable terminal EN, and the voltage-stabilized power supply 10 will quickly stop enabling.

[0091] Taking the voltage-stabilized power supply 10 as a linear power supply with an enable threshold of 3V and an input of 12V / 3A as an example, its Simulink simulation results are shown in Figure 15, which are, from top to bottom, the input voltage, i.e., the first voltage Vin, the output voltage, i.e., the second voltage Vout, the load current IO, and the enable voltage Ven.

[0092] In this embodiment, at 10 ms, the first voltage Vin starts to be input, the voltage-regulated power supply 10 starts to work, the second voltage Vout is 12 V, and the load current is 0.1 A;

[0093] At 40ms, the load current increases to 1A, and the voltage-stabilized power supply 10 operates normally. As the load increases, the second voltage Vout decreases slightly to 11.7V.

[0094] At 70ms, the output is short-circuited, and the short-circuit current is about 10A. The voltage-stabilized power supply 10 performs active protection based on the internal program, that is, it attempts to restart the voltage-stabilized power supply 10 every 1ms, and the enable voltage Ven begins to drop. After the short circuit lasts for about 10ms, the enable voltage Ven drops below 3V, the voltage-stabilized power supply 10 loses its enable, stops working, and no longer outputs, and the short-circuit protection is completed.

[0095] The following example uses the voltage-regulated power supply 10 as a buck switching power supply, with a first voltage of 48V, an enable threshold of 3V, and an output of 12V / 3A. The PSpice simulation results are shown in FIG16 , where Vin is the first voltage, Vout is the second voltage, Ven is the enable voltage, and I0 is the load current.

[0096] At 1ms, the first voltage Vin starts to be input, the switching power supply starts to work, the second voltage Vout is 13V, and the load current I0 is 10mA;

[0097] At 5ms, the load current I0 increases to 100mA, the switching power supply works normally, and the second voltage Vout is 13V;

[0098] At 12 ms, the second voltage Vout begins to drop, and at 16 ms, the switching power supply stops working; this process is a normal power supply control process.

[0099] At 26ms, the first voltage Vin is established, the switching power supply starts working again, the second voltage Vout is 13V, and the load current I0 is 100mA;

[0100] At 35ms, the output is short-circuited, and the short-circuit current, i.e., the load current I0, is about 10A. The load capacity of the switching power supply is insufficient, the second output voltage Vout is pulled down, and the enable voltage Ven begins to drop. After the short circuit lasts for about 1.3ms, the enable voltage Ven drops below 3V, the voltage-stabilized power supply loses enable, stops working, and no longer outputs, and the short-circuit protection is completed.

[0101] The power supply circuit 100 of the present application uses a voltage-stabilized power supply 10 with an enabling function, does not require additional active devices or sampling resistors, and only needs to configure a small amount of resistors and capacitors to achieve short-circuit protection, greatly reducing application costs.

[0102] In summary, according to the power supply circuit of the embodiment of the present disclosure, the input end of the voltage-stabilized power supply is suitable for being connected to an external power supply, the input end of the enabling unit is suitable for being connected to an external power supply, the input end of the enabling unit is connected to the output end of the voltage-stabilized power supply, the output end of the enabling unit is connected to the enabling end of the voltage-stabilized power supply, the voltage-stabilized power supply converts the first voltage provided by the external power supply into a second voltage, and when the external power supply starts to provide the first voltage, the enabling unit outputs a first enabling signal based on the first voltage to enable the voltage-stabilized power supply to start working, and when the voltage-stabilized power supply outputs a second voltage and the second voltage is less than or equal to a preset voltage threshold, the enabling unit outputs a protection signal based on the second voltage to enable the voltage-stabilized power supply to stop working and enter a protection state. Thus, when the second voltage output by the voltage-stabilized power supply is less than or equal to the preset voltage threshold, the circuit can output a protection signal to the enabling end of the voltage-stabilized power supply based on the second voltage to control the voltage-stabilized power supply to stop working and enter a protection state, thereby reducing the degree of failure of the circuit and eliminating the need to add an additional short-circuit protection circuit, thereby reducing the application cost.

[0103] Corresponding to the above embodiments, the present disclosure also proposes an electrical device.

[0104] As shown in Fig. 17, an electrical device 1000 according to an embodiment of the present disclosure includes the aforementioned power supply circuit 100. The electrical device 100 is a power-consuming device that uses a stabilized voltage, such as an air conditioner, a compressor, and the like.

[0105] According to the electrical device of the embodiment of the present disclosure, based on the above-mentioned power supply circuit, when the second voltage output by the regulated power supply is less than or equal to the preset voltage threshold, the control circuit stops working and enters a protection state, thereby reducing the failure degree of the circuit in the electrical device and eliminating the need to add an additional short-circuit protection circuit, thereby reducing the application cost.

[0106] Corresponding to the above embodiments, the present disclosure also proposes a vehicle.

[0107] As shown in FIG. 18 , a vehicle 2000 according to an embodiment of the present disclosure includes the power supply circuit 100 described above.

[0108] According to the vehicle 2000 of the embodiment of the present disclosure, it includes the power supply circuit 100 described in any of the above embodiments. Here, the vehicle 2000 can be a new energy vehicle. In some embodiments, the new energy vehicle can be a pure electric vehicle with a motor as the main driving force. In other embodiments, the new energy vehicle can also be a hybrid vehicle with an internal combustion engine and a motor as the main driving force. Regarding the internal combustion engine and the motor mentioned in the above embodiments that provide driving power for the new energy vehicle, the internal combustion engine can use gasoline, diesel, hydrogen, etc. as fuel, and the way to provide electrical energy for the motor can use power batteries, hydrogen fuel cells, etc., and no special limitation is made here. It should be noted that this is only an exemplary description of the structure of new energy vehicles, etc., and it does not limit the scope of protection of the present disclosure.

[0109] According to the vehicle of the embodiment of the present disclosure, based on the above-mentioned power supply circuit, when the second voltage output by the regulated power supply is less than or equal to the preset voltage threshold, the power supply circuit can be controlled to stop working and enter a protection state, thereby reducing the failure degree of the vehicle circuit and eliminating the need to add an additional short-circuit protection circuit, thereby reducing the application cost.

[0110] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0111] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0112] In this disclosure, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components, unless otherwise expressly limited. Those skilled in the art will understand the specific meanings of the above terms in this disclosure based on specific circumstances.

[0113] Although the embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are illustrative and are not to be construed as limitations on the present disclosure. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present disclosure.

Claims

1. A power supply circuit comprising: a voltage-stabilized power supply, wherein an input end of the voltage-stabilized power supply is adapted to be connected to an external power supply and is configured to convert a first voltage provided by the external power supply into a second voltage; An enabling unit, wherein the input end of the enabling unit is suitable for being connected to the external power supply, the input end of the enabling unit is connected to the output end of the regulated power supply, and the output end of the enabling unit is connected to the enable end of the regulated power supply, and is used to output a first enabling signal based on the first voltage when the external power supply starts to provide the first voltage, so that the regulated power supply starts to work, and when the regulated power supply outputs the second voltage and the second voltage is less than or equal to a preset voltage threshold, output a protection signal based on the second voltage, so that the regulated power supply stops working and is in a protection state.

2. The power supply circuit according to claim 1, wherein The enabling unit is further configured to, when the regulated power supply outputs the second voltage and the second voltage is greater than the preset voltage threshold, output a second enabling signal based on the second voltage to keep the regulated power supply working.

3. The power supply circuit according to claim 2, wherein: The enabling unit includes: a first capacitor, a first resistor, and a second resistor, one end of the first capacitor is suitable for being connected to the external power supply, the other end of the first capacitor, one end of the first resistor, and one end of the second resistor are respectively connected to the enabling end of the regulated power supply, the other end of the first resistor is grounded, and the other end of the second resistor is connected to the output end of the regulated power supply.

4. The power supply circuit according to claim 3, wherein: The enabling unit further includes: a diode, wherein an anode of the diode is adapted to be connected to the external power supply, and a cathode of the diode is connected to one end of the first capacitor.

5. The power supply circuit according to claim 3 or 4, wherein: The enabling unit further includes: a third resistor, and the third resistor is connected in parallel with the first capacitor.

6. The power supply circuit according to any one of claims 1 to 5, wherein: The power supply circuit further includes: a reset unit, wherein a reset terminal of the reset unit is connected to an enable terminal of the regulated power supply, and is configured to output a reset signal when the regulated power supply is in a protection state and a preset reset condition is satisfied, so as to enable the regulated power supply to exit the protection state and start working; The preset reset condition includes that the reset unit receives an external reset control instruction or the reset unit determines that the duration of the voltage-regulated power supply being in the protection state reaches a preset duration.

7. The power supply circuit according to claim 6, wherein: The input end of the reset unit is connected to the enable end of the regulated power supply, and is used to determine whether the duration of the regulated power supply being in the protection state reaches a preset duration based on the voltage of the enable end; or, The input end of the reset unit is connected to the output end of the regulated power supply, and is used to determine whether the duration of the regulated power supply being in the protection state reaches a preset duration based on the second voltage; or, The input end of the reset unit and the status output end of the regulated power supply are used to determine whether the duration of the regulated power supply in the protection state reaches a preset duration based on the status signal of the status output end, wherein the feedback end of the regulated power supply is connected to the output end of the regulated voltage to obtain the second voltage, and generate the status signal based on the second voltage.

8. The power supply circuit according to any one of claims 1 to 7, wherein: The power supply circuit further includes: A second capacitor is connected in series between the input terminal of the regulated power supply and the ground.

9. The power supply circuit according to any one of claims 1 to 8, wherein: The power supply circuit further includes: a third capacitor connected in series between the output terminal of the regulated power supply and the ground; A fourth resistor is connected in parallel with the third capacitor.

10. The power supply circuit according to any one of claims 1 to 9, wherein: The voltage-stabilized power supply includes a linear voltage-stabilized power supply, a switching voltage-stabilized power supply or a low voltage difference voltage-stabilized power supply.

11. An electrical device comprising the power supply circuit according to any one of claims 1 to 10.

12. A vehicle comprising the power supply circuit according to any one of claims 1 to 10.

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