Electronic fuse, power distribution unit, and vehicle electrical system

Abstract

The invention relates to an electronic fuse connected between a power source and a load to be powered by the power source, the electronic fuse comprising: a reference terminal; an output terminal; a sampling terminal; the fusing circuit comprises a measuring resistor and an electronic switch; the control chip is connected to the fusing circuit on one hand and connected to the sampling terminal on the other hand, and the control chip is configured to receive a feedback signal from the load through the sampling terminal and calculate the maximum protection current corresponding to the load based on the received feedback signal; monitoring voltage values at the two ends of the measuring resistor in real time in the operation process of the load, and calculating power supply current flowing to the load based on the voltage values; and turning off the electronic switch when the supply current exceeds the maximum protection current of the load. The invention also relates to a power distribution unit comprising the electronic fuse, and to a vehicle electrical system comprising the power distribution unit.

Description

Technical Field

[0001] The present invention relates to the field of fuses. More specifically, the present invention relates to an electronic fuse, a power distribution unit including the electronic fuse, and a vehicle electrical system including the power distribution unit. Background Art

[0002] A fuse is also known as a "fuse wire". It is an electrical component used to ensure the safety of a circuit. Its working principle is: when the current in the circuit is too high or an abnormal fault occurs, in order to avoid damaging the components in the circuit, the fuse wire melts itself to cut off the current in the circuit, thereby playing a role in protecting the safe operation of the circuit.

[0003] In the field of fuses, it can be generally divided into traditional fuse wires and modern electronic fuses (e-Fuse). Traditional fuse wires are disposable and non-self-recoverable. Once they melt, they need to be replaced. This disposable characteristic makes traditional fuse wires less practical and economical in many applications. Although self-recovery fuse wires are still used in some specific scenarios, the cost of such self-recovery fuse wires is extremely high.

[0004] With the development of fuse wire technology, electronic fuses (e-Fuse) have emerged. Although e-Fuse solves the problems of traditional fuse wires to a certain extent, they still have some limitations. The current e-Fuse technology cannot support software to automatically read the maximum protection current corresponding to different loads, which means that users cannot automatically match the corresponding current protection value according to different loads. In addition, the current e-Fuse cannot implement open circuit detection of the load power supply harness, which may lead to potential safety problems and risks of equipment damage. Summary of the Invention

[0005] In view of the above defects existing in the existing fuse wires, the present invention provides a more efficient, safer and more intelligent electronic fuse solution. The electronic fuse aims to: 1) solve the non-recoverable disadvantage of traditional fuse wires and improve the service life and economy of the fuse; 2) solve the problem that the existing electronic fuses (e-Fuse) cannot automatically match the current protection value according to different loads and achieve intelligent current protection for the circuit; 3) solve the disadvantage that the current e-Fuse cannot implement open circuit detection of the load power supply wire and improve the safety and reliability of the system.

[0006] A first aspect of the present invention provides an electronic fuse. The electronic fuse is connected between a power supply and a load to be powered by the power supply. The electronic fuse includes:

[0007] A reference terminal, the reference terminal being grounded;

[0008] An output terminal, the output terminal being connected to an input terminal in the load;

[0009] A sampling terminal, the sampling terminal being configured to receive a feedback signal from the load;

[0010] A fusing circuit connected in series between the power supply and the output terminal, the fusing circuit including a measuring resistor and an electronic switch; and

[0011] A control chip, the control chip being connected to the fusing circuit on one hand and to the sampling terminal on the other hand, wherein the control chip is configured to:

[0012] Receive a feedback signal from the load via the sampling terminal and calculate the maximum protection current corresponding to the load based on the received feedback signal;

[0013] During operation of the load, monitor in real time the voltage value across the measuring resistor and calculate the supply current flowing to the load based on this voltage value; and

[0014] When the supply current exceeds the maximum protection current of the load, turn off the electronic switch.

[0015] According to an optional embodiment, the electronic fuse includes a first voltage detection device and a second voltage detection device, the first voltage detection device being configured to feedback an indication voltage indicating the maximum protection current of the load to the sampling terminal of the electronic fuse during operation of the load, the second voltage detection device being configured to provide the output voltage of the power supply to the control chip,

[0016] wherein the control chip is configured to calculate the maximum protection current corresponding to the load based on the indication voltage feedback by the first voltage detection device and the output voltage provided by the second voltage detection device.

[0017] According to an optional embodiment, the first voltage detection device includes a voltage dividing circuit connected in series between the output terminal and the reference terminal of the electronic fuse, the voltage dividing circuit being composed of a first voltage dividing resistor and a second voltage dividing resistor, wherein the control chip is configured to calculate the indication voltage based on the voltage at the voltage dividing point between the first voltage dividing resistor and the second voltage dividing resistor.

[0018] According to an optional embodiment, the second voltage detection device includes a measuring circuit connected in series between the power supply and the reference terminal, the measuring circuit being composed of a first measuring resistor and a second measuring resistor, wherein the control chip is configured to calculate the output voltage of the power supply based on the node voltage between the first measuring resistor and the second measuring resistor.

[0019] According to an optional embodiment, the load includes a storage chip that stores the maximum protection current corresponding to the load, and the storage chip is configured to directly transmit the maximum protection current corresponding to the load to the control chip of the electronic fuse during the operation of the load.

[0020] According to an optional embodiment, the load includes a plurality of electronic devices with different maximum protection currents. Each electronic device includes an input terminal connected to the output terminal of the electronic fuse, a feedback terminal connected to the control chip, and a ground terminal (P1_3, P2_3) connected to the reference terminal of the electronic fuse.

[0021] According to an optional embodiment, the control chip is further configured to determine which wire harness in the electronic fuse has an open circuit by monitoring the open circuit voltage at the sampling terminal when an open circuit fault occurs in the electronic fuse.

[0022] According to an optional embodiment, the control chip is further configured to monitor the voltage across the electronic switch in real time during the operation of the load, and determine whether the electronic switch has a fault based on the monitored voltage.

[0023] The second aspect of the present invention also provides a power distribution unit for a vehicle. According to an optional embodiment, the power distribution unit includes at least one electronic fuse as described above.

[0024] The second aspect of the present invention also provides a vehicle electrical system, which includes:

[0025] A power source;

[0026] A load to be powered by the power source; and

[0027] The electronic fuse as described above.

[0028] Compared with traditional e-Fuses, the electronic fuse according to the present invention has the following advantages: it can automatically match the current protection values of different loads through software, simplifies the configuration process, and improves the convenience of product use; it can detect the open circuit of the load power supply line, improving the system safety and fault diagnosis ability; within the current range allowed by the wire harness, it supports replacing loads with different maximum protection currents, and the software can automatically identify and match the current protection values without manual intervention; it adopts a platform design, supports the vehicle configuration and production of multiple vehicle models, reduces the number of vehicle BOMs, reduces production debugging positions and single-vehicle production time, and improves production efficiency and production capacity per unit time; it improves the intelligent level of the vehicle electrical system, provides a hardware basis for the traceability of vehicle current distribution, and is conducive to optimizing energy management and fault analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] By incorporating the accompanying drawings herein and subsequently with the attached Figure 1 Certain specific embodiments used to illustrate some principles of the present invention, other features and advantages of the method of the present invention will become clear or be more specifically illustrated.

[0030] Figure 1 A circuit schematic diagram of an existing electronic fuse (e-Fuse) is shown.

[0031] Figure 2 A circuit diagram of an electronic fuse according to an exemplary embodiment of the present invention is shown.

[0032] Figure 3 A circuit diagram of an electronic fuse according to another exemplary embodiment of the present invention is shown.

[0033] Figure 4 A circuit diagram of an electronic fuse according to yet another exemplary embodiment of the present invention is shown. Detailed Description of the Invention

[0034] The electronic fuse according to the present invention will be described below with reference to the accompanying drawings and by way of examples. In the following description, many specific details are set forth in order to enable those skilled in the art to more fully understand the present invention. However, it is obvious to those skilled in the art that some of these specific details may not be required for the implementation of the present invention. On the contrary, the present invention can be implemented by considering any combination of the following features and elements, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments and advantages are for illustrative purposes only and should not be regarded as elements or limitations of the claims.

[0035] Figure 1 A circuit schematic diagram of an existing electronic fuse (e-Fuse) is shown. As Figure 1 shown, the e-Fuse is usually connected between a load and its power supply. Its main function is to cut off the circuit when the current exceeds a preset threshold (determined by monitoring the voltage value across resistor R) - this cut-off action is particularly achieved by controlling the electronic switch T through a control chip, thereby protecting the load connected to the circuit from excessive current damage. Once the fault is eliminated, the electronic fuse can automatically resume connection without the need for replacement or repair. Through this connection method, the electronic fuse can play a protective role in the circuit, ensuring that the load operates within a safe current range. At the same time, due to the self-recovery function of the electronic fuse, it has higher practicality and economy in many application scenarios and has more advantages than traditional fuses.

[0036] However, this existing e-Fuse still has certain limitations. For example, it cannot support software to automatically read the maximum protection current corresponding to different loads, which means that users cannot automatically match the corresponding current protection value according to different loads. In addition, the current e-Fuse cannot implement the open circuit detection of the load power supply harness, which may lead to potential safety problems and risks of equipment damage.

[0037] The present invention aims to improve and optimize the existing e-Fuse and proposes a new type of electronic fuse. Figure 2 The circuit diagram of the electronic fuse according to an exemplary embodiment of the present invention is shown.

[0038] As Figure 2 shown, the e-Fuse is connected between the power supply V_BAT and the load to be powered by the power supply V_BAT. The e-Fuse generally includes a reference terminal P_GND, an output terminal P_OUT, and a sampling terminal P_FEED, where the reference terminal P_GND is grounded, the output terminal P_OUT is connected to the input terminal in the load, and the sampling terminal P_FEED is used to receive a feedback signal from the load.

[0039] Unlike the existing e-Fuse, Figure 2 the electronic fuse in [[ ]] includes a fuse circuit connected in series between the power supply V_BAT and the output terminal P_OUT. The fuse circuit may particularly include a measuring resistor RS and an electronic switch T1. The on / off of the electronic switch T1 is controlled by a control chip IC1. The control chip IC1 is connected to the fuse circuit on one hand and to the sampling terminal P_FEED on the other hand to receive a feedback signal from the load via the sampling terminal P_FEED. Based on this feedback signal, the control chip IC1 can calculate the maximum protection current corresponding to the load it is connected to.

[0040] In addition, during the operation of the load, the control chip IC1 can continuously monitor the voltage value across the measuring resistor RS in the fuse circuit and calculate the supply current flowing to the load based on this voltage value. When the supply current exceeds the maximum protection current of the load, the control chip IC1 disconnects the electronic switch T1 to cut off the current in the circuit.

[0041] In this article, the load can be, for example, an electronic device in a vehicle, such as a lower-level controller for controlling various vehicle functions. Figure 2Two electronic devices E1 and E2 are shown as loads, and these two electronic devices may have different maximum protection currents. The input terminal P1_1 of the electronic device E1 is connected to the output terminal P_OUT of the electronic fuse, the feedback terminal P1_2 of the electronic device E1 is connected to the control chip IC1, the ground terminal P1_3 of the electronic device E1 is connected to the reference terminal P_GND of the electronic fuse, the input terminal P2_1 of the electronic device E2 is connected to the output terminal P_OUT of the electronic fuse, the feedback terminal P2_2 of the electronic device E2 is connected to the control chip IC1, and the ground terminal P2_3 of the electronic device E1 is connected to the reference terminal P_GND of the electronic fuse.

[0042] However, it can be understood that, in addition to Figure 2 the two electronic devices E1 and E2 shown in

[0043] In Figure 2 the embodiment of

[0044] In order to determine the maximum protection current corresponding to the electronic devices connected to the circuit, the electronic fuse may further include first and second voltage detection devices, and these two detection devices may be respectively arranged at the fuse end and the load end. Among them, the first voltage detection device is used to feedback an indication voltage indicating the maximum protection current of the load to the sampling terminal P_FEED of the electronic fuse during the operation of the load. Specifically, the first voltage detection device includes a voltage dividing circuit connected in series between the output terminal P_OUT and the reference terminal P_GND of the electronic fuse, and this voltage dividing circuit is composed of a first voltage dividing resistor R1 and a second voltage dividing resistor R2. Among them, the control chip IC1 can calculate the indication voltage based on the voltage at the voltage dividing point between the first voltage dividing resistor R1 and the second voltage dividing resistor R2.

[0045] The second voltage detection device is used to provide the output voltage of the power supply V_BAT to the control chip IC1 during the operation of the load. Specifically, the second voltage detection device includes a measurement circuit connected in series between the power supply V_BAT and the reference terminal P_GND, and this measurement circuit is composed of a first measurement resistor RV1 and a second measurement resistor RV2. Among them, the control chip IC1 can calculate the output voltage of the power supply V_BAT based on the node voltage between the first measurement resistor RV1 and the second measurement resistor RV2.

[0045] Finally, the control chip IC1 can calculate the maximum protection current corresponding to the load based on the indication voltage fed back by the first voltage detection device and the output voltage provided by the second voltage detection device.

[0046] Next, in combination with Figure 2Introduce the operation process of the electronic fuse in this embodiment in detail.

[0047] First, the control chip IC1 controls the switch T1 to close. The current inputs from V_BAT and flows through Rs, T1, terminal P_OUT, power supply line A, terminal P1_1 in sequence, and finally enters the next-level controller E1. Then, it returns to the ground terminal GND through terminal P1_3, ground wire C, and terminal P_GND. The next-level controller E1 obtains power supply and starts to operate.

[0048] During the operation of the controller E1, the control chip IC1 calculates the output voltage V_BAT of the power supply through the measured voltage division of resistors Rv1 and Rv2. At the same time, the control chip IC1 obtains the indication voltage of the maximum protection current of the next-level controller at terminal P_FEED through resistors R1 and R2, wire harnesses A, B, and C, and terminal P1_2. The control chip IC1 can calculate the maximum protection current of the next-level controller based on this indication voltage and the V_BAT voltage.

[0049] In addition, according to an optional example, when an open-circuit fault occurs in the electronic fuse (for example, when the wire harnesses A, B, or C connecting the lower-level controller are disconnected), the control chip IC1 can also determine which specific wire harness (for example, power supply line A, maximum current feedback line B, or ground wire C) in the electronic fuse is open by monitoring the open-circuit voltage at the sampling terminal P_FEED.

[0050] When an open-circuit fault is detected or the power supply current exceeds the maximum protection current of the next-level controller, the control chip IC1 can control the switch T1 to open, thereby stopping the power supply to the next-level controller E1.

[0051] Because of different vehicle configurations, the e-Fuse will supply power to different next-level controllers. For example, replace controller 1 with controller E2. The control chip IC1 will also detect the maximum current indication voltage provided by the resistors R11 and R12 inside the lower-level controller E2 at P_FEED and further calculate the maximum protection current of the controller E2.

[0052] In addition, the control chip IC1 can collect and measure the voltage value across the resistor RS to calculate the power supply current to the next-level controller E1 or E2.

[0053] According to another optional example, during the operation of the load, the control chip IC1 can also monitor the voltage across the electronic switch T1 in real time and determine whether the electronic switch T1 fails based on the monitored voltage.

[0054] Optionally, the control chip IC1 can control multiple electronic switches simultaneously to supply power to different next-level controllers. The current values corresponding to the switch combinations - such as RS and T1 - can be configured in a stepped manner.

[0055] In Figure 2 the embodiment, in order to determine the maximum protection current of the load, the first and second voltage detection devices must be set. However, another more convenient implementation can be envisioned, such as Figure 3 shown in Figure 3 the embodiment, the load itself includes a storage chip storing the maximum protection current corresponding to the load, and the storage chip can directly transmit the maximum protection current corresponding to the load to the control chip IC1 of the electronic fuse when the load is running. Therefore, this embodiment can omit Figure 2 the first and second voltage detection devices set to determine the maximum protection current in

[0056] Next, in combination with Figure 3 the operation process of the electronic fuse of this embodiment will be introduced in detail.

[0057] First, the control chip IC1 controls the switch T1 to close, and the current inputs from V_BAT, flows through RS, T1, terminal P_OUT, harness A in sequence, and finally enters the next-level controller E1 via terminal P1_1. Subsequently, the current returns to the ground terminal GND via terminal P1_3, harness C, and terminal P_GND. The next-level controller E1 can obtain power supply and work properly.

[0058] When the next-level controller E1 starts to work, the storage chip therein transmits the stored maximum protection current to the control chip IC1 at the e-Fuse end.

[0059] Because of different vehicle configurations, the e-Fuse supplies power to different next-level controllers. For example, replace the controller E1 with the controller E2. The control chip IC1 will also obtain the maximum protection current stored in the storage chip of the controller E2.

[0060] In addition, the control chip IC1 can collect and measure the voltage value across the measurement resistor RS, and thereby calculate the supply current to the next-level controller E2.

[0061] Optionally, the control chip IC1 can also collect the voltage across the MOSFET T1, and thereby calculate and detect whether an irrecoverable fault occurs in the switch T1.

[0062] When the current flowing through RS exceeds the maximum protection current of the next-level controller E1 or E2, the control chip IC1 controls the switch T1 to open, thereby stopping the power supply to the next-level control.

[0063] In addition, the control chip IC1 can control multiple switches simultaneously and supply power to different next-level controllers. The current values corresponding to switch combinations - such as RS and T1 - can be configured stepwise.

[0064] In Figure 2 and Figure 3 embodiments, the electronic fuse includes only one fusing circuit and one control chip IC1, and all loads (such as electronic devices E1, E2) are controlled by this fusing circuit and control chip IC1. However, it can be understood that, as in Figure 4 shown in another embodiment, the electronic fuse according to the present invention may also include multiple fusing circuits composed of measuring resistors RS and electronic switches T1, and each fusing circuit has a corresponding control chip.

[0065] Another embodiment of the present invention also proposes a power distribution unit (PDU) for a vehicle, which includes at least one of the above-described electronic fuses.

[0066] Another embodiment of the present invention also proposes a vehicle electrical system, which includes: a power source V_BAT; a load to be powered by the power source V_BAT; and an electronic fuse as described above.

[0067] Compared with traditional e-Fuses, the electronic fuse according to the present invention has the following advantages: it can automatically match the current protection values of different loads in a software manner, simplifies the configuration process, and improves the convenience of product use; it can detect the open circuit of the load power supply line, improving the system safety and fault diagnosis ability; within the current range allowed by the wiring harness, it supports replacing loads with different maximum protection currents, and the software can automatically identify and match the current protection values without manual intervention; it adopts a platform design, supports the vehicle configuration and production of multiple vehicle models, reduces the vehicle BOM quantity, reduces production debugging positions and single-vehicle production time, and improves production efficiency and unit-time production capacity; it improves the intelligent level of the vehicle electrical system, provides a hardware basis for the traceability of vehicle current distribution, and is conducive to optimizing energy management and fault analysis.

[0068] Those skilled in the art can understand that the steps of the method according to the present invention are not limited to being implemented in the order listed above. In addition, in the present invention, terms such as "comprising" and "including" mean that in addition to the steps directly and clearly described in the specification and claims, the technical solutions of the present application do not exclude the situation of having other steps that are not directly or clearly described.

[0069] Although the present invention has been disclosed above in preferred embodiments, the present invention is not limited thereto. Any person skilled in the art, without departing from the spirit and scope of the present invention, makes various changes and modifications, which should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. An electronic fuse, which is connected between a power supply (V_BAT) and a load to be powered by the power supply (V_BAT), characterized in that, The electronic fuse includes: A reference terminal (P_GND) that is grounded. An output terminal (P_OUT) that is connected to the input terminals (P1_1, P2_1) in the load. A sampling terminal (P_FEED) that is used to receive a feedback signal from the load. A fusing circuit connected in series between the power supply (V_BAT) and the output terminal (P_OUT), the fusing circuit including a measurement resistor (RS) and an electronic switch (T1); and A control chip (IC1) that is connected to the fusing circuit on one hand and to the sampling terminal (P_FEED) on the other hand, wherein the control chip is configured to: - Receive a feedback signal from the load via the sampling terminal (P_FEED) and estimate the maximum protection current corresponding to the load based on the received feedback signal; - During the operation of the load, monitor in real time the voltage value across the measurement resistor (RS) and estimate the supply current flowing to the load based on this voltage value; and - When the supply current exceeds the maximum protection current of the load, turn off the electronic switch (T1).

2. The electronic fuse according to claim 1, characterized in that, The electronic fuse includes a first voltage detection device and a second voltage detection device. The first voltage detection device is configured to, during the operation of the load, feed back an indication voltage indicating the maximum protection current of the load to the sampling terminal (P_FEED) of the electronic fuse. The second voltage detection device is configured to provide the output voltage of the power supply (V_BAT) to the control chip (IC1). Wherein the control chip (IC1) is configured to calculate the maximum protection current corresponding to the load based on the indication voltage fed back by the first voltage detection device and the output voltage provided by the second voltage detection device.

3. The electronic fuse according to claim 2, characterized in that, The first voltage detection device includes a voltage division circuit connected in series between the output terminal (P_OUT) and the reference terminal (P_GND) of the electronic fuse. The voltage division circuit is composed of a first voltage division resistor (R1) and a second voltage division resistor (R2). The control chip (IC1) is configured to estimate the indication voltage based on the voltage at the voltage division point between the first voltage division resistor (R1) and the second voltage division resistor (R2).

4. The electronic fuse according to claim 2, characterized in that, The second voltage detection device includes a measurement circuit connected in series between the power supply (V_BAT) and the reference terminal (P_GND). The measurement circuit is composed of a first measurement resistor (RV1) and a second measurement resistor (RV2). The control chip (IC1) is configured to estimate the output voltage of the power supply (V_BAT) based on the node voltage between the first measurement resistor (RV1) and the second measurement resistor (RV2).

5. The electronic fuse according to claim 1, characterized in that, The load includes a memory chip storing the maximum protection current corresponding to the load, and the memory chip is configured to directly transmit the maximum protection current corresponding to the load to the control chip (IC1) of the electronic fuse during the operation of the load.

6. The electronic fuse according to any one of claims 1 to 5, characterized in that, The load includes a plurality of electronic devices (E1, E2) having different maximum protection currents. Each electronic device includes an input terminal (P1_1, P2_1) connected to the output terminal (P_OUT) of the electronic fuse, a feedback terminal (P1_2, P2_2) connected to the control chip (IC1), and a ground terminal (P1_3, P2_3) connected to the reference terminal (P_GND) of the electronic fuse.

7. The electronic fuse according to any one of claims 1 to 5, characterized in that, The control chip (IC1) is further configured to determine which wire harness in the electronic fuse is open by monitoring the open-circuit voltage at the sampling terminal (P_FEED) when an open-circuit fault occurs in the electronic fuse.

8. The electronic fuse according to any one of claims 1 to 5, characterized in that, The control chip (IC1) is further configured to monitor the voltage across the electronic switch (T1) in real time during the operation of the load and determine whether the electronic switch (T1) is faulty based on the monitored voltage.

9. A power distribution unit for a vehicle, characterized in that, The power distribution unit includes at least one electronic fuse according to any one of claims 1 to 8.

10. A vehicle electrical system, characterized in that, The system includes: a power supply (V_BAT); a load to be powered by the power supply (V_BAT); and an electronic fuse according to any one of claims 1 to 8.

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