Power supply circuit and power supply device

Abstract

The utility model provides a power supply circuit and a power supply device. When the rear-end load is in a normal working state, the fuse works in an awakening mode, electric energy of the front-end power supply can be transmitted to the rear-end load through the fuse and the first power supply circuit, the large-current power utilization requirement of the rear-end load is met, and at the moment, the energy storage circuit is charged through the first power supply circuit; when the rear-end load is in a standby state or a dormant state and the fuse works in a dormant mode, the electric energy of the front-end power supply can be transmitted to the rear-end load through the fuse and the second power supply circuit, and the low-current power utilization requirement of the rear-end load is met; when the rear-end load enters some specific application states from the dormant state, the fuse still works in the dormant mode, and the electric energy transmitted by the second power supply circuit and the electric energy generated by discharging of the energy storage circuit can meet the transient current power utilization requirement of the rear-end load in a specific application scene.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a power supply circuit and a power supply device. Background Art

[0002] As the electronic architecture of the whole vehicle develops towards the regional control architecture, smart fuses are gradually replacing traditional fuses. In order to meet the low power consumption requirements of the whole vehicle, smart fuses have two working modes: wake-up mode and sleep mode. In wake-up mode, the smart fuse runs through a large current, while in sleep mode it can only provide a small current with a peak value of about 0.1A. When the peak value of the small current is exceeded, the smart fuse will wake up the regional controller of the whole vehicle. This causes the regional controller of the whole vehicle to be woken up frequently, which in turn increases the low power consumption of the whole vehicle.

[0003] In this way, when the smart fuse is in sleep mode, it is necessary to require that the current required by the load at the back end of the smart fuse cannot exceed the maximum current transmitted by the smart fuse in sleep mode. Although the current required by most loads when the smart fuse is in sleep mode will not exceed the maximum current transmitted by the smart fuse in sleep mode, some dedicated modules have application scenarios with transient currents, such as NFC modules. That is, the current transmitted by the smart fuse in sleep mode to the NFC module cannot meet the transient large current required by the NFC module in some application scenarios. Therefore, it is necessary to design a power supply solution that is suitable for such dedicated modules with transient currents. Utility Model Content

[0004] The purpose of the utility model is to provide a power supply circuit and a power supply device to solve the problem that the prior art does not have a power supply solution for a smart fuse and a dedicated module adapted to the presence of transient current, which causes the regional controller of the whole vehicle to be frequently awakened, thereby increasing the low power consumption of the whole vehicle.

[0005] To solve the above technical problems, based on one aspect of the utility model, the utility model provides a power supply circuit, the power supply circuit is used to be connected between a fuse and a rear-end load, the fuse works in one of a wake-up mode and a sleep mode, and the maximum value of the current transmitted by the fuse working in the sleep mode is less than the maximum value of the current transmitted by the fuse working in the wake-up mode, and the power supply circuit includes:

[0006] a first power supply circuit, the first power supply circuit being used to be connected between the fuse and the rear-end load, the first power supply circuit being operated when the fuse works in the wake-up mode, and transmitting the current on the fuse to the rear-end load;

[0007] a second power supply circuit connected in parallel with the first power supply circuit, the second power supply circuit operates when the fuse operates in a sleep mode and transmits the current on the fuse to the rear-end load;

[0008] An energy storage circuit connected to the first power supply circuit, the first power supply circuit charges the energy storage circuit when it is running, and the energy storage circuit can be discharged to the rear-end load when the second power supply circuit is running.

[0009] Optionally, the first power supply circuit includes a first power switch tube and a driving unit, the fuse is connected to the input end of the first power switch tube, the output end of the first power switch tube is connected to the back-end load and the energy storage circuit, the driving unit is connected to the driving end of the first power switch tube, and drives the first power switch tube to conduct when the fuse operates in the wake-up mode.

[0010] Optionally, the driving unit includes a first resistor, a second resistor, a third resistor, a fourth resistor and a second power switch tube, the input end of the second power switch tube is connected to the input end of the first power switch tube through the first resistor and the second resistor connected in series, a lead-out line between the first resistor and the second resistor is connected to the driving end of the first power switch tube, the output end of the second power switch tube is grounded, one end of the third resistor is used to connect an enable signal, the other end of the third resistor is grounded through the fourth resistor, and the driving end of the second power switch tube is connected between the third resistor and the fourth resistor; when the fuse works in the wake-up mode, the enable signal is valid to generate a bias voltage between the third resistor and the fourth resistor to turn on the second power switch tube.

[0011] Optionally, the first power switch tube is a PMOS tube or a PNP transistor, and the second power switch tube is an NPN transistor or an NMOS tube.

[0012] Optionally, the driving unit further includes a third diode, which is a Zener diode, a cathode end of the third diode is connected to the input end of the first power switch tube, and an anode end of the third diode is connected between the first resistor and the second resistor.

[0013] Optionally, the second power supply circuit includes a third power switch and a current limiting control unit, the input end and the driving end of the third power switch tube are both connected to the current limiting control unit, the output end of the third power switch tube is used to connect the back-end load, the current limiting control unit is connected to the fuse, and the current limiting control unit is used to limit the maximum value of the current flowing through the third power switch tube to be less than the maximum value of the current transmitted by the first power supply circuit; the current limiting control unit is also used to turn on the third power switch tube when the fuse is operating in sleep mode.

[0014] Optionally, the current limiting unit includes a fifth resistor, a sixth resistor, a seventh resistor and a fourth power switch tube, the fifth resistor and the seventh resistor are connected in series to ground the fuse, the input end of the third power switch tube and the driving end of the third power switch tube are both connected between the fifth resistor and the seventh resistor, the input end of the fourth power switch tube is connected to the fuse, the output end of the fourth power switch tube is connected between the fifth resistor and the seventh resistor, and the driving end of the fourth power switch tube is connected between the fifth resistor and the seventh resistor through the sixth resistor; a bias voltage is generated between the fifth resistor and the seventh resistor to turn on the third power switch tube and cut off the fourth power switch tube when the fuse works in sleep mode.

[0015] Optionally, the third power switch tube is a PMOS tube or a PNP transistor, and the fourth power switch tube is a PNP transistor or a PMOS tube.

[0016] Optionally, the current limiting control unit also includes a fourth diode, which is a Zener diode, a cathode end of the fourth diode is connected to the input end of the third power switch, and an anode end of the fourth diode is connected to the driving end of the fourth power switch tube.

[0017] The power supply circuit also includes an anti-reverse connection protection circuit, the positive end of the anti-reverse connection protection circuit is used to connect the fuse, and the reverse end of the anti-reverse connection protection circuit is connected to the first power supply circuit and the second power supply circuit.

[0018] Optionally, the power supply circuit further includes a second diode, which is a transient voltage suppression diode, and one end of each of the first power supply circuit and the second power supply circuit for connecting to the fuse is grounded through the second diode.

[0019] To solve the above technical problems, based on another aspect of the utility model, the utility model also provides a power supply device, which includes a fuse and a power supply circuit as described above, the fuse works in one of the wake-up mode and the sleep mode, and the maximum value of the current transmitted by the fuse working in the sleep mode is less than the maximum value of the current transmitted by the fuse working in the wake-up mode, the first power supply circuit and the second power supply circuit are connected in parallel between the fuse and the rear-end load, the fuse is connected to the front-end power supply, and the energy storage circuit is used to connect the rear-end load.

[0020] As for the power supply circuit above, when the rear-end load is in normal working state, the fuse will work in the wake-up mode, and the electric energy of the front-end power supply can be transmitted to the rear-end load through the fuse and the first power supply circuit to meet the large current power demand of the rear-end load, and at this time, the energy storage circuit is charged through the first power supply circuit; when the rear-end load is in standby state or dormant state, the fuse will work in the dormant mode, and the electric energy of the front-end power supply can be transmitted to the rear-end load through the fuse and the second power supply circuit to meet the small current power demand of the rear-end load; when the rear-end load enters some specific application states from the dormant state, the fuse still works in the dormant mode, and the electric energy transmitted by the second power supply circuit and the electric energy generated by the discharge of the energy storage circuit can meet the transient large current power demand of the rear-end load in specific application scenarios. In this way, the power supply circuit of the utility model not only meets the power demand of the rear-end load in normal working state and the power demand in dormant state, but also meets the power demand of the rear-end load for transient current, avoiding the situation that the regional controller of the whole vehicle is frequently awakened, resulting in an increase in the low power consumption of the whole vehicle.

[0021] It should be noted that, since the power supply device includes the power supply circuit, it also has the technical effects brought by the power supply circuit, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Those skilled in the art should understand that the drawings provided are for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0023] Figure 1 It is a schematic diagram of a power supply circuit according to an embodiment of the present utility model.

[0024] 10-front-end power supply; 20-fuse; 30-first power supply circuit; 31-driving unit; 40-second power supply circuit; 41-current limiting control unit; 50-energy storage circuit; 60-rear-end load;

[0025] M1-first power switch tube; M2-second power switch tube; M3-third power switch tube; M4-fourth power switch tube;

[0026] D1-first diode; D2-second diode; D3-third diode; D4-fourth diode;

[0027] R1-first resistor; R2-second resistor; R3-third resistor; R4-fourth resistor; R5-fifth resistor; R6-sixth resistor; R7-seventh resistor;

[0028] C-energy storage capacitor. DETAILED DESCRIPTION

[0029] In order to make the purpose, advantages and features of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0030] As used in the present invention, the singular forms "one", "an" and "the" include plural objects, the term "or" is usually used to include the meaning of "and / or", the term "several" is usually used to include the meaning of "at least one", and the term "at least two" is usually used to include the meaning of "two or more". In addition, the terms "first", "second" and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" and "third" may explicitly or implicitly include one or at least two of the features, "one end" and "the other end" and "the proximal end" and "the distal end" generally refer to two corresponding parts, which not only include the endpoints, and the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. In addition, as used in the present invention, an element disposed on another element generally only indicates that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the connection, coupling, cooperation or transmission between the two elements may be direct or indirect through an intermediate element, and cannot be understood as indicating or implying the spatial position relationship between the two elements, that is, an element may be in any orientation such as inside, outside, above, below or on one side of another element, unless otherwise clearly indicated in the content. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Figure 1Schematic diagram of a power supply circuit of an embodiment of the utility model. Figure 1 As shown, an embodiment of the utility model schematically provides a power supply circuit, which is applied to a power supply device, and the power supply device includes a fuse 20, the fuse 20 is connected to the front-end power supply 10, and the front-end power supply 10 here can be, for example, a battery of a whole vehicle, and the fuse 20 is connected to the rear-end load 60 through the power supply circuit, so that the electric energy of the front-end power supply 10 is transmitted to the rear-end load 60 through the fuse 20 and the power supply circuit, and the rear-end load 60 is powered. The fuse 20 is specifically a smart fuse, which has two working modes, including a wake-up mode and a sleep mode, and the fuse 20 operates in one of the wake-up mode and the sleep mode, and the maximum value of the current transmitted by the fuse 20 working in the sleep mode is less than the maximum value of the current transmitted by the fuse 20 working in the wake-up mode. The power supply circuit includes a first power supply circuit 30, a second power supply circuit 40 and a storage circuit 50, and the first power supply circuit 30 and the second power supply circuit 40 are connected in parallel and connected between the fuse 20 and the rear-end load 60. The first power supply circuit 30 operates when the fuse 20 works in the wake-up mode, and transmits the current on the fuse 20 to the rear-end load 60. The second power supply circuit 40 operates when the fuse 20 operates in the sleep mode, and transmits the current on the fuse 20 to the rear-end load 60. The energy storage circuit 50 and the first power supply circuit 30, the first power supply circuit 30 charges the energy storage circuit 50 when it is running, so that the energy storage capacitor C stores electric energy, and the energy storage circuit 50 can be discharged to the rear-end load 60 when the second power supply circuit 40 is running. In one embodiment, the energy storage circuit 50 can be an energy storage capacitor C, one end of the energy storage capacitor C is connected between the first power supply circuit 30 and the rear-end load 60, and the other end of the energy storage capacitor C is grounded. The rear-end load 60 can be, for example, an NFC (Near Field Communication) module of a car, and there are application scenarios that require transient current.

[0032] In this way, when the rear-end load 60 is in a normal working state, the fuse 20 will work in the wake-up mode, and the electric energy of the front-end power supply 10 can be transmitted to the rear-end load 60 through the fuse 20 and the first power supply circuit 30 to meet the large current power demand of the rear-end load 60, and at this time, the energy storage circuit 50 is charged through the first power supply circuit 30; when the rear-end load 60 is in a standby state or a dormant state, the fuse 20 will work in the dormant mode, and the electric energy of the front-end power supply 10 can be transmitted to the rear-end load 60 through the fuse 20 and the second power supply circuit 40 to meet the small current power demand of the rear-end load 60; when the rear-end load 60 enters some specific application states from the dormant state, the fuse 20 still works in the dormant mode, and the electric energy transmitted by the second power supply circuit 40 and the electric energy generated by the discharge of the energy storage circuit 50 can meet the transient large current power demand of the rear-end load 60 in specific application scenarios. In this way, the power supply circuit of the utility model not only meets the power demand of the rear-end load 60 in normal working state and the power demand in sleep state, but also meets the power demand of the rear-end load 60 requiring transient current, thereby avoiding the situation where the regional controller of the whole vehicle is frequently awakened, resulting in increased low power consumption of the whole vehicle.

[0033] Continue reading Figure 1 The first power supply circuit 30 includes a first power switch tube M1 and a drive unit 31. The fuse 20 is connected to the input end of the first power switch tube M1. The output end of the first power switch tube M1 is connected to the rear-end load 60 and the energy storage circuit 50. The drive unit 31 is connected to the drive end of the first power switch tube M1, and drives the first power switch tube M1 to conduct when the fuse 20 works in the wake-up mode. Specifically, when the control system of the whole vehicle switches the working mode of the fuse 20 to the wake-up mode, it synchronously outputs a valid enable signal (MCU_EN) to the drive unit 31. After receiving the valid enable signal, the drive unit 31 conducts the first power switch tube M1, thereby transmitting the current to the rear-end load 60 through the fuse 20 and the conducted first power switch tube M1.

[0034] Furthermore, the driving unit 31 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a second power switch tube M2, the input end of the second power switch tube M2 is connected to the input end of the first power switch tube M1 through the first resistor R1 and the second resistor R2 connected in series, a lead line is drawn between the first resistor R1 and the second resistor R2 to connect the driving end of the first power switch tube M1, the output end of the second power switch tube M2 is grounded, one end of the third resistor R3 is used to access the enable signal, the other end of the third resistor R3 is grounded through the fourth resistor R4, and the driving end of the second power switch tube M2 is connected between the third resistor R3 and the fourth resistor R4; when the fuse 20 works in the wake-up mode, the enable signal is valid to generate a bias voltage between the third resistor R3 and the fourth resistor R4 to turn on the second power switch tube M2. In this way, the control system of the whole vehicle continuously outputs an enable signal (MCU_EN) to the third resistor R3. When the control system switches the working mode of the fuse 20 to the wake-up mode, the control system adjusts the enable signal to be valid, thereby generating a bias voltage between the third resistor R3 and the fourth resistor R4 to turn on the second power switch tube M2. After the second power switch tube M2 is turned on, under the action of the voltage of the front-end power supply 10, a bias voltage to turn on the first power switch tube M1 can be generated between the first resistor R1 and the second resistor R2.

[0035] Exemplarily, the first power switch tube M1 is a PMOS tube, the input end of the first power switch tube M1 is the source, the output end of the first power switch tube M1 is the drain, and the driving end of the first power switch tube M1 is the gate. Of course, the first power switch tube M1 can also be a PNP triode, the input end of the first power switch tube M1 is the emitter, the output end of the first power switch tube M1 is the collector, and the driving end of the first power switch tube M1 is the base. Exemplarily, the second power switch tube M2 is an NPN triode, the input end of the second power switch tube M2 is the collector, the output end of the second power switch tube M2 is the emitter, and the driving end of the second power switch tube M2 is the base. Of course, the second power switch tube M2 can also be an NMOS tube, the input end of the second power switch tube M2 is the drain, the output end of the second power switch tube M2 is the source, and the driving end of the second power switch tube M2 is the gate. In this way, when the enable signal is valid (it can be considered that the enable signal is valid when it is a high-level signal), a high level is generated between the third resistor R3 and the fourth resistor R4 to turn on the second power switch tube M2. After the second power switch tube M2 is turned on, a low level is generated between the first resistor R1 and the second resistor R2 to turn on the first power switch tube M1.

[0036] Preferably, the driving unit 31 further includes a third diode D3, which is a Zener diode, a cathode end of the third diode D3 connected to the input end of the first power switch tube M1, and an anode end of the third diode D3 connected between the first resistor R1 and the second resistor R2. The third diode D3 can be set to clamp the conduction voltage (turn on) of the first power switch tube M1, for example, the V GS Clamping is performed.

[0037] Continue reading Figure 1 , the second power supply circuit 40 includes a third power switch tube M3 and a current limiting control unit 41, the input end of the third power switch tube M3 and the driving end of the third power switch tube M3 are both connected to the current limiting control unit 41, the output end of the third power switch tube M3 is used to connect the rear-end load 60, the current limiting control unit 41 is connected to the fuse 20, and the current limiting control unit 41 is used to limit the maximum value of the current flowing through the third power switch tube M3 to be less than the maximum value of the current transmitted by the first power supply circuit 30; the current limiting control unit 41 is also used to turn on the third power switch tube M3 when the fuse 20 works in the sleep mode. In this way, when the fuse 20 works in the sleep mode, the third power switch tube M3 can be turned on by the current limiting control unit 41, and the current flowing through the third power switch tube M3 can be limited by the current limiting control unit 41, so as to ensure that a small current supplies power to the rear-end load 60 in the sleep mode.

[0038] Further, the current limiting unit includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7 and a fourth power switch tube M4. The fifth resistor R5 and the seventh resistor R7 are connected in series to ground the fuse 20. The input end of the third power switch tube M3 and the driving end of the third power switch tube M3 are both connected between the fifth resistor R5 and the seventh resistor R7. The input end of the fourth power switch tube M4 is connected to the fuse 20. The output end of the fourth power switch tube M4 is connected between the fifth resistor R5 and the seventh resistor R7. The driving end of the fourth power switch tube M4 is connected between the fifth resistor R5 and the seventh resistor R7 through the sixth resistor R6. A bias voltage that turns on the third power switch tube M3 and turns off the fourth power switch tube M4 is generated between the fifth resistor R5 and the seventh resistor R7 when the fuse 20 works in the sleep mode. Thus, when the fuse 20 works in the sleep mode, the fuse 20 transmits a small current, the fourth power switch tube M4 is turned off, the third power switch tube M3 is turned on, the fifth resistor R5 serves as a current limiting resistor, and the maximum value of the current flowing through the third power switch tube M3 is the voltage between the input end and the driving end of the fourth power tube divided by the resistance value of the fifth resistor R5. When the fuse 20 works in the wake-up mode, the fuse 20 transmits a large current, the third power switch tube M3 is turned off, and the fourth power switch tube M4 is turned on, and the voltage of the front-end power supply 10 is grounded.

[0039] Exemplarily, the third power switch tube M3 is a PMOS tube, the input end of the third power switch tube M3 is the source, the output end of the third power switch tube M3 is the drain, and the driving end of the third power switch tube M3 is the gate. Of course, the first power switch tube M1 can also be a PNP transistor, the input end of the third power switch tube M3 is the emitter, the output end of the third power switch tube M3 is the collector, and the driving end of the third power switch tube M3 is the base. Exemplarily, the fourth power switch tube M4 is a PMOS tube, the input end of the fourth power switch tube M4 is the source, the output end of the fourth power switch tube M4 is the drain, and the driving end of the fourth power switch tube M4 is the gate. Of course, the fourth power switch tube M4 can also be a PNP transistor, the input end of the fourth power switch tube M4 is the emitter, the output end of the fourth power switch tube M4 is the collector, and the driving end of the fourth power switch tube is the base. In this way, the maximum value of the current flowing through the third power switch tube M3 is V of the fourth transistor. BE Further, the resistance ratio between the sixth resistor R6 and the fifth resistor R5 can be configured to be greater than 100, thereby reducing the influence of the current at the driving end of the fourth power tube on the second power supply circuit 40 as a whole.

[0040] Preferably, the current limiting control unit 41 further includes a fourth diode D4, which is a Zener diode, a cathode end of the fourth diode D4 connected to the input end of the third power switch, and an anode end of the fourth diode D4 connected to the driving end of the fourth power switch tube M4. The fourth diode D4 is provided to clamp the conduction voltage (turn on) of the third power switch tube M3, for example, the V GS Clamping is performed.

[0041] Preferred, continue reading Figure 1 , the power supply circuit also includes an anti-reverse connection protection circuit, the positive end of the anti-reverse connection protection circuit is used to connect the fuse 20, and the reverse end of the anti-reverse connection protection circuit is connected to the first power supply circuit 30 and the second power supply circuit 40. In this way, when the positive end of the anti-reverse connection protection circuit is connected to the positive end of the front-end power supply 10 through the fuse 20, a path is presented between the front-end power supply 10 and the first power supply circuit 30 (or the second power supply circuit 40) to transfer electric energy normally; when the positive end of the anti-reverse connection protection circuit is connected to the negative end of the front-end power supply 10 through the fuse 20, the anti-reverse connection protection circuit is turned off, and an open circuit is presented between the front-end power supply 10 and the first power supply circuit 30 (or the second power supply circuit 40) to perform anti-reverse connection protection. In one embodiment, the anti-reverse connection protection circuit includes a second diode D2, the anode end of the second diode D2 is connected to the fuse 20, and the cathode tube of the second diode D2 is connected to the first power supply circuit 30 and the second power supply circuit 40, and is specifically connected to the input end of the first power switch tube M1 and the fifth resistor R5.

[0042] Preferably, continue to refer to Figure 1 , the power supply circuit also includes a second diode D2, the second diode D2 is a transient voltage suppression diode (TVS tube), the first power supply circuit 30 and the second power supply circuit 40 are each used to connect the one end of the fuse 20 to the ground through the second diode D2, that is, the second diode D2 grounds the voltage on the fuse 20. The second diode D2 is set to suppress the instantaneous voltage on the front-end power supply 10, and at the same time protect the voltage between the output end and the driving end of the first power switch tube M1 from exceeding the maximum voltage limited by the device parameters between the output end and the driving end of the first power switch tube M1, and at the same time protect the voltage between the output end and the driving end of the third power switch tube M3 from exceeding the maximum voltage limited by the device parameters between the output end and the driving end of the third power switch tube M3. For example, the protection of the V DS The maximum voltage that does not exceed the device parameter limit of the first power switch tube M1, and the V of the third power switch tube M3 that protects the PMOS tube DS The maximum voltage does not exceed the device parameter limit of the third power switch tube M3.

[0043] Based on the above-mentioned power supply circuit, an embodiment of the utility model further provides a power supply device, which includes a fuse 20 and the power supply circuit as described above, the fuse 20 works in one of the wake-up mode and the sleep mode, and the maximum value of the current transmitted by the fuse 20 working in the sleep mode is less than the maximum value of the current transmitted by the fuse 20 working in the wake-up mode, the first power supply circuit 30 and the second power supply circuit 40 are connected in parallel and connected between the fuse 20 and the rear-end load 60, the fuse 20 is connected to the front-end power supply 10, and the energy storage circuit 50 is connected to the rear-end load 60.

[0044] Although the utility model is disclosed as above with preferred embodiments, the above embodiments are not intended to limit the utility model. For any technician familiar with the art, without departing from the scope of the technical solution of the utility model, the above disclosed technical content can be used to make many possible changes and modifications to the technical solution of the utility model, or modified into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the utility model without departing from the content of the technical solution of the utility model still falls within the scope of protection of the technical solution of the utility model.

Claims

1. A power supply circuit, applied to a fuse, wherein the fuse operates in one of a wake-up mode and a sleep mode, and the maximum value of the current transmitted by the fuse operating in the sleep mode is smaller than the maximum value of the current transmitted by the fuse operating in the wake-up mode, characterized in that: The power supply circuit comprises: a first power supply circuit, the first power supply circuit being used to be connected between the fuse and the rear-end load, the first power supply circuit being operated when the fuse works in the wake-up mode, and transmitting the current on the fuse to the rear-end load; a second power supply circuit connected in parallel with the first power supply circuit, the second power supply circuit operates when the fuse operates in a sleep mode and transmits the current on the fuse to the rear-end load; An energy storage circuit connected to the first power supply circuit, the first power supply circuit charges the energy storage circuit when it is running, and the energy storage circuit can discharge to the rear-end load when the second power supply circuit is running.

2. The power supply circuit according to claim 1, characterized in that: The first power supply circuit includes a first power switch tube and a driving unit, the input end of the first power switch tube is used to connect to the fuse, the output end of the first power switch tube is connected to the back-end load and the energy storage circuit, the driving unit is connected to the driving end of the first power switch tube, and drives the first power switch tube to conduct when the fuse works in the wake-up mode.

3. The power supply circuit according to claim 2, characterized in that: The driving unit includes a first resistor, a second resistor, a third resistor, a fourth resistor and a second power switch tube. The input end of the second power switch tube is connected to the input end of the first power switch tube through the first resistor and the second resistor connected in series. A lead line between the first resistor and the second resistor is connected to the driving end of the first power switch tube. The output end of the second power switch tube is grounded. One end of the third resistor is used to access an enable signal, and the other end of the third resistor is grounded through the fourth resistor. The driving end of the second power switch tube is connected between the third resistor and the fourth resistor. When the fuse works in the wake-up mode, the enable signal is valid to generate a bias voltage between the third resistor and the fourth resistor to turn on the second power switch tube.

4. The power supply circuit according to claim 3, characterized in that: The first power switch tube is a PMOS tube or a PNP transistor, and the second power switch tube is an NPN transistor or an NMOS tube.

5. The power supply circuit according to claim 3, characterized in that: The driving unit further includes a third diode, which is a Zener diode. A cathode end of the third diode is connected to an input end of the first power switch tube, and an anode end of the third diode is connected between the first resistor and the second resistor.

6. The power supply circuit according to claim 1, characterized in that: The second power supply circuit includes a third power switch tube and a current limiting control unit, the input end and the driving end of the third power switch tube are both connected to the current limiting control unit, the output end of the third power switch tube is used to connect the back-end load, the current limiting control unit is connected to the fuse, and the current limiting control unit is used to limit the maximum value of the current flowing through the third power switch tube to be less than the maximum value of the current transmitted by the first power supply circuit; the current limiting control unit is also used to turn on the third power switch tube when the fuse is working in sleep mode.

7. The power supply circuit according to claim 6, characterized in that: The current limiting unit includes a fifth resistor, a sixth resistor, a seventh resistor and a fourth power switch tube. The fifth resistor and the seventh resistor are connected in series to ground the fuse. The input end of the third power switch tube and the driving end of the third power switch tube are both connected between the fifth resistor and the seventh resistor. The input end of the fourth power switch tube is connected to the fuse. The output end of the fourth power switch tube is connected between the fifth resistor and the seventh resistor. The driving end of the fourth power switch tube is connected between the fifth resistor and the seventh resistor through the sixth resistor. A bias voltage is generated between the fifth resistor and the seventh resistor to turn on the third power switch tube and turn off the fourth power switch tube when the fuse works in the sleep mode.

8. The power supply circuit according to claim 7, characterized in that: The third power switch tube is a PMOS tube or a PNP transistor, and the fourth power switch tube is a PNP transistor or a PMOS tube.

9. The power supply circuit according to claim 7, characterized in that: The current limiting control unit also includes a fourth diode, which is a Zener diode. The cathode end of the fourth diode is connected to the input end of the third power switch, and the anode end of the fourth diode is connected to the driving end of the fourth power switch tube.

10. The power supply circuit according to claim 1, characterized in that: The power supply circuit also includes an anti-reverse connection protection circuit, the positive end of the anti-reverse connection protection circuit is used to connect the fuse, and the reverse end of the anti-reverse connection protection circuit is connected to the first power supply circuit and the second power supply circuit.

11. The power supply circuit according to claim 1, characterized in that: The power supply circuit further includes a second diode, which is a transient voltage suppression diode. One end of each of the first power supply circuit and the second power supply circuit for connecting to the fuse is grounded through the second diode.

12. A power supply device, characterized in that: It includes a fuse and a power supply circuit as described in any one of claims 1 to 11, the fuse operates in one of a wake-up mode and a sleep mode, and the maximum value of the current transmitted by the fuse operating in the sleep mode is less than the maximum value of the current transmitted by the fuse operating in the wake-up mode, the first power supply circuit and the second power supply circuit are used to be connected in parallel between the fuse and a rear-end load, the fuse is used to connect a front-end power supply, and the energy storage circuit is used to connect the rear-end load.

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