Fuse device, battery management system, and battery pack

Abstract

The present disclosure relates to a fuse device, a battery management system, and a battery pack, and is directed to providing a circuit configuration capable of integrally performing a diagnosis function and an ignition function of a fuse serving as a protection element provided in a battery pack. To this end, the fuse device includes a fuse element, a diagnosis current supply circuit connected to the fuse element and configured to allow a diagnosis current for diagnosing the fuse element to flow through the fuse element, and an ignition circuit connected to the diagnosis current supply circuit and configured to allow an ignition current for ignition of the fuse element to flow through the fuse element. Diagnosis and ignition operations of the fuse element are performed by controlling activation of the diagnosis current supply circuit and the ignition circuit.

Description

Technical Field

[0001] This disclosure relates to fuse devices, battery management systems, and battery packs. Background Technology

[0002] A battery pack consists of individual battery cells and peripheral circuitry, including charging / discharging circuitry. The peripheral circuitry is manufactured as a printed circuit board and then connected to the battery cells. When an external power source is connected to the external terminals of the battery pack, the battery cells are charged. When a load is connected to the external terminals, the battery cells are discharged. The charging / discharging circuitry controls the charging / discharging of the battery cells between the external terminals and the battery cells themselves. Typically, the battery cells are connected in series and parallel depending on the load's capacity consumption.

[0003] When abnormal power operation of the battery pack occurs, such as when overcurrent flows from the battery pack to the load, it is necessary to protect the battery pack, the load, the product to which the battery pack is applied, and the user. To achieve such protection, the current path connected to the battery (i.e., the current path from the individual battery cells to the load) is blocked. In particular, a fuse can be used to block the flow of current by physically cutting off the current path connected to the battery.

[0004] The information disclosed in this section is intended to enhance understanding of the background of this disclosure. It may contain information that does not constitute relevant or prior art. Summary of the Invention

[0005] This disclosure aims to provide a fuse device, a battery management system, and a battery pack capable of performing the diagnostic and ignition functions of a fuse, wherein the fuse is a protective element provided in the battery pack.

[0006] However, the purposes achieved by this disclosure are not limited to those described above, and other purposes not described will be clearly understood by those skilled in the art based on the following description.

[0007] A fuse device according to an embodiment of the present disclosure includes a fuse element configured to block a current path connected to a battery, a diagnostic current supply circuit connected to the fuse element and configured to allow a diagnostic current for diagnosing the fuse element to flow through the fuse element, and an ignition circuit connected to the diagnostic current supply circuit and configured to allow an ignition current for igniting the fuse element to flow through the fuse element, wherein the diagnostic current supply circuit is configured to generate a diagnostic current regardless of whether the ignition circuit is activated, and the ignition circuit is configured to generate an ignition current depending on whether the diagnostic current supply circuit is activated.

[0008] The ignition circuit may include an ignition switch configured to turn on in response to an input of at least one of a first ignition signal and a second ignition signal to form an ignition current in a fuse element, and a first processor configured to apply the first ignition signal to control the operation of the fuse device, and a second processor configured to apply the second ignition signal, wherein the second processor acts as an upper controller of the first processor.

[0009] The diagnostic current supply circuit may include a switch and a resistor. The switch is connected to the ignition switch in a cascode manner and is configured to turn on in response to the input of a diagnostic signal. The resistor is connected to the ignition switch and the connection node to which the switch is connected. When the switch is on, the diagnostic current may be configured to flow along a current path connected to the fuse element, the switch, the resistor, and the ground node.

[0010] The diagnostic current can be a constant current with an amplitude determined by the resistance value of the resistor.

[0011] When both the ignition switch and the switch are on, the ignition current can be configured to flow along the current path connected to the fuse element, the switch, the ignition switch and the ground node.

[0012] The switch can be configured to turn on in response to the input of at least one of a diagnostic signal and a second ignition signal, and the diagnostic current supply circuit can also include a delay circuit configured to delay the turn-on time of the switch relative to the time when the diagnostic signal or the second ignition signal is input.

[0013] This switch is the first switch. The diagnostic current supply circuit may also include a second switch, which is cascaded to the first switch and configured to turn on the first switch in response to an input diagnostic signal or a second ignition signal.

[0014] The fuse assembly may also include a drive circuit and a resistance monitoring circuit. The drive circuit is configured to allow or block current flow from a first power node to which a first power supply voltage is applied to the fuse element. The resistance monitoring circuit is configured to monitor the resistance value of the internal resistance of the fuse element based on the voltage across the fuse element.

[0015] When the resistance value of the internal resistance of the fuse element, as monitored by the resistance monitoring circuit, is outside a preset range, the drive circuit can be configured to block the current flow to the fuse element.

[0016] The fuse assembly may also include a switch monitoring circuit, which includes a monitoring resistor connected between a second power node to which a second power supply voltage is applied and a connection node to monitor for abnormalities in the first switch and the ignition switch.

[0017] The magnitude of the voltage formed at the connection node can be configured to vary depending on whether the first switch and the ignition switch are in the on or off state.

[0018] A battery management system according to an embodiment of the present disclosure includes a fuse element configured to block a current path connected to a battery, a diagnostic current supply circuit connected to the fuse element and configured to allow a diagnostic current for diagnosing the fuse element to flow through the fuse element, an ignition circuit connected to the diagnostic current supply circuit and configured to allow an ignition current for igniting the fuse element to flow through the fuse element, and a processor configured to (i) diagnose the fuse element by disabling the ignition circuit and activating the diagnostic current supply circuit to form a diagnostic current, and (ii) ignite the fuse element by activating both the diagnostic current supply circuit and the ignition circuit to form an ignition current.

[0019] The ignition circuit may include an ignition switch configured to turn on in response to an input of at least one of a first ignition signal and a second ignition signal to form an ignition current in a fuse element, and the diagnostic current supply circuit may include a first switch and a first resistor, the first switch being connected to the ignition switch in a common-source, common-gate manner and turning on in response to an input of a diagnostic signal, and the first resistor being connected to the ignition switch and the connection node to which the first switch is connected.

[0020] The battery management system may also include a drive circuit and a resistance monitoring circuit. The drive circuit allows or blocks the flow of current from a first power node to a fuse element when a first power supply voltage is applied. The resistance monitoring circuit is configured to monitor the resistance value of the internal resistance of the fuse element. When monitoring the resistance value of the internal resistance of the fuse element, the processor may be configured to control the drive circuit to allow the flow of current from the first power node to the fuse element.

[0021] When monitoring the internal resistance of a fuse element, the processor (i) can control the diagnostic current supply circuit to allow diagnostic current to flow through the fuse element, and (ii) can monitor the internal resistance of the fuse element through the resistance monitoring circuit while the diagnostic current flows through the fuse element.

[0022] The processor can be configured to monitor the resistance value of the internal resistance of the fuse element based on the voltage across the fuse element identified by the resistance monitoring circuit and the amplitude of the diagnostic current.

[0023] The processor can be configured to determine that an abnormality has occurred in the fuse element when the resistance value of the internal resistance of the fuse element monitored by the resistance monitoring circuit is outside a preset range, and to block the current flow from the first power node to the fuse element by the drive circuit.

[0024] The processor can be configured to determine whether a fuse element is short-circuited based on the voltage across the fuse element identified by a resistance monitoring circuit, and when a short circuit is detected in the fuse element, the processor is configured to control the drive circuit to block the current flow from the first power node to the fuse element.

[0025] The battery management system may also include a switch monitoring circuit, which includes a monitoring resistor connected between a second power node to which a second power supply voltage is applied and a connection node to monitor for anomalies in the first switch and the ignition switch. The processor may be configured to monitor the anomalies in the first switch and the ignition switch by monitoring the amplitude of a voltage formed at the connection node, wherein the amplitude of the voltage formed at the connection node may be configured to vary depending on whether the first switch and the ignition switch are in an on or off state.

[0026] A battery pack according to an embodiment of the present disclosure includes a battery, a fuse element configured to block a current path connected to the battery, a diagnostic current supply circuit connected to the fuse element and configured to allow a diagnostic current for diagnosing the fuse element to flow through the fuse element, an ignition circuit connected to the diagnostic current supply circuit and configured to allow an ignition current for igniting the fuse element to flow through the fuse element, and a processor configured to (i) diagnose the fuse element by disabling the ignition circuit and activating the diagnostic current supply circuit to form a diagnostic current, and (ii) ignite the fuse element by activating both the diagnostic current supply circuit and the ignition circuit to form an ignition current. Attached Figure Description

[0027] The accompanying drawings illustrate embodiments of the present disclosure, and together with the detailed description of the present disclosure, various aspects and features of the present disclosure are further described. The present disclosure is not limited to the embodiments depicted in the drawings.

[0028] Figure 1 This is a block diagram of a battery management system and a battery pack according to an embodiment of the present disclosure;

[0029] Figure 2 This is a block diagram of a fuse device according to an embodiment of the present disclosure;

[0030] Figure 3 This is a circuit diagram of a fuse device according to an embodiment of the present disclosure;

[0031] Figures 4A to 4CThis is an exemplary diagram illustrating the fuse diagnostic operation of a fuse apparatus according to an embodiment of the present disclosure; and

[0032] Figure 5 This is an exemplary diagram of the fuse ignition operation of a fuse device according to an embodiment of the present disclosure. Detailed Implementation

[0033] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be construed as limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical spirit of the present disclosure, based on the principle that the inventor may be his / her own lexicographer to appropriately define the concepts of the terms in order to best interpret his / her invention.

[0034] The embodiments described in this specification and the configurations shown in the accompanying drawings are merely some embodiments of this disclosure and do not represent all technical ideas, aspects, and features of this disclosure. Therefore, it should be understood that various equivalents and modifications may exist to replace or modify the embodiments described herein at the time of filing this application.

[0035] It should be understood that when a component or layer is described as being "on another component or layer," "connected to another component or layer," or "bonded to another component or layer," it can be directly on, connected to, or bonded to another component or layer, or one or more intermediate components or layers may be present. When a component or layer is described as being "directly on another component or layer," "directly connected to another component or layer," or "directly bonded to another component or layer," no intermediate components or layers are present. For example, when a first component is described as being "bonded" or "connected" to a second component, the first component can be directly bonded to or connected to the second component, or the first component can be indirectly bonded to or connected to the second component via one or more intermediate components.

[0036] In the accompanying drawings, the dimensions of various elements, layers, etc., may be exaggerated for clarity. The same reference numerals designate the same elements. As used herein, the term "and / or" includes any and all combinations of one or more associated listed items. Furthermore, when describing embodiments of this disclosure, the use of "may" refers to "one or more embodiments of this disclosure." Expressions such as "at least one of..." and "any one of..." modify the entire list of elements when preceding it, and do not modify individual elements in the list. When phrases such as "at least one of A, B, and C," "at least one of A, B, or C," "at least one selected from the group consisting of A, B, and C," or "at least one selected from A, B, and C" are used to specify a list of elements A, B, and C, the phrase may refer to any and all suitable combinations or subsets of A, B, and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the terms “use,” “using,” and “used” can be considered synonymous with the terms “utilize,” “utilizing,” and “utilized,” respectively. As used herein, the terms “substantially,” “about,” and similar terms are used as approximations rather than terms of degree and are intended to explain the inherent changes in measured or calculated values ​​that will be recognized by one of ordinary skill in the art.

[0037] It should be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or portion discussed below may be referred to as the second element, component, region, layer, or portion.

[0038] For ease of description, this document uses spatial relative terms such as “beneath,” “below,” “lower,” “above,” “upper,” etc., to describe the relationship between one element or feature and another, as shown in the accompanying drawings. It should be understood that, in addition to the orientations depicted in the drawings, the spatial relative terms are intended to cover different orientations of the device in use or operation. For example, if the device in the drawings is flipped, an element described as “below” or “under” other elements or features will be oriented as “above” or “over” other elements or features. Thus, the term “below” can encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein should be interpreted accordingly.

[0039] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit this disclosure. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that, when used in this specification, the terms “includes,” “including,” “comprises,” and / or “comprising” specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0040] Furthermore, any numerical range disclosed and / or described herein includes all subranges with the same numerical precision contained within said range. For example, the range “1.0 to 10.0” includes all subranges between (and including) the minimum value of 1.0 and the maximum value of 10.0, i.e., a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit described herein includes all lower numerical limits contained therein, and any minimum numerical limit described in this specification includes all higher numerical limits contained therein. Therefore, the applicant reserves the right to amend this specification (including the claims) to expressly describe any subranges contained within the scope expressly described herein.

[0041] Referring to two compared elements, features, etc., as “identical” can mean that they are “substantially identical.” Therefore, the phrase “substantially identical” can include cases with deviations considered low in the art, such as 5% or less. Furthermore, when a particular parameter is said to be uniform in a given region, it can mean that it is uniform in terms of average value.

[0042] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0043] When any element is said to be set (or located or positioned) "above (or below)" or "on top of (or below)" an assembly, it can mean that the element is placed in contact with the upper (or lower) surface of the assembly, and it can also mean that another assembly can be situated between the assembly and any arbitrary element set (or located or positioned) above (or below) the assembly.

[0044] Furthermore, it should be understood that when a component is referred to as being "joined," "linked," or "connected" to another component, the components can be directly "joined," "linked," or "connected" to each other, or there can be an intermediate component through which the components can be "joined," "linked," or "connected" to the other component. Additionally, when a part is referred to as being "electrically joined" to another part, the part can be directly connected to the other part, or there can be an intermediate part through which the part and the other part are indirectly connected to each other.

[0045] Throughout this specification, when stated as “A and / or B,” it means A, B, or A and B, unless otherwise stated. That is, “and / or” includes any or all combinations of the listed items. When stated as “C to D,” unless otherwise specified, it means C or above and D or below.

[0046] 1. Battery Management System and Battery Pack

[0047] Figure 1 This is a block diagram of a battery management system and a battery pack according to embodiments of the present disclosure.

[0048] refer to Figure 1 The battery management system (BMS) of this embodiment may include a monitoring processor (MP), a central processing unit (CP), a shunt resistor (SR), a charge / discharge switch (SW), a switch driver (SDRV), a regulator (REG), and a fuse device (F). The BMS may be part of a battery pack (P) and a battery battery (BAT). In this embodiment, the battery pack (P) can be used as a power source for small electronic devices such as mobile phones, laptops, or cameras. In other embodiments, the battery pack (P) can be used as a power source for industrial devices such as electric vehicles (EVs), hybrid vehicles (HVs), or energy storage systems (ESS). Hereinafter, embodiments in which the battery pack (P) is used in an electric vehicle will be described.

[0049] The battery BAT can correspond to a battery module (including structures in which battery cells C are connected in series or parallel) where individual battery cells C are connected in series or parallel. When the battery pack P is used in an electric vehicle, the battery BAT can be implemented as a high-voltage battery (e.g., lithium-ion battery, lithium polymer battery, nickel-cadmium battery, nickel-metal hydride battery, nickel-zinc battery, etc.) that supplies high voltage (e.g., 400V or 800V). The battery BAT can be the main battery that drives the system by supplying power to a load. That is, the battery BAT can be part of the electric vehicle's drive system (e.g., drive motor and inverter), and the battery BAT can be charged by charging current supplied from an external charging device. Separately from the main battery BAT, an auxiliary battery (e.g., lead-acid battery) (not shown) for supplying low-voltage power (e.g., 12V) to the electric vehicle's electrical systems (e.g., lighting system, wiper system, air conditioning system, etc.) can be provided in the battery pack P.

[0050] The monitoring processor MP can correspond to an analog front-end (AFE) integrated circuit (IC) that monitors the state of each battery cell C and performs battery cell control operations based on the monitoring results. For example, the monitoring processor MP can be configured to monitor the voltage, current, temperature, and state of charge (SOC) of battery cell C. Furthermore, the monitoring processor MP can perform control operations based on the monitoring results, such as balancing control, temperature control, and charge / discharge control of battery cell C, or perform protection operations, such as controlling the charge / discharge switch SW to prevent over-discharge or over-charge. The state data of battery cell C acquired by the monitoring processor MP (i.e., the voltage, current, temperature, and SOC of battery cell C) can be transmitted to the central processing unit CP via an isolated serial peripheral interface (ISOSPI) communication.

[0051] The central processing unit (CP) can generate control or protection operation commands based on the status data of the battery cell C sent from the monitoring processor (MP), and feed the status data back to the monitoring processor (MP) to allow the monitoring processor (MP) to perform the aforementioned control and protection operations. The central processing unit (CP) performing these functions can correspond to the microcontroller unit (MCU) of the BMS. The central processing unit (CP) can communicate with the upper-level controller (CTRLER) (e.g., the electronic control unit (ECU) of the vehicle in which the battery pack P is installed) via communication protocols such as Controller Area Network (CAN), Real-Time Clock (RTC), and / or Universal Asynchronous Receiver / Transmitter (UART) (the processor CP and the first processor CP indicated in the claims of this specification refer to the central processing unit (CP), and the second processor CTRLER refers to the upper-level controller CTRLER, such as the vehicle's ECU).

[0052] The shunt resistor SR is connected on the path from the positive terminal P+ of the battery pack P through the battery cell C to the negative terminal P- of the battery pack P (corresponding to the charging / discharging path). The shunt resistor SR can be used as a resistive element for detecting overcurrent flowing in the battery cell C.

[0053] The charge / discharge switch SW can correspond to a metal-oxide-semiconductor field-effect transistor (MOSFET) that controls the current flow in the aforementioned charge / discharge path. The switch driver SDRV can correspond to a gate driver that controls the on / off operation of the charge / discharge switch SW under the control of the central processing unit CP.

[0054] The monitoring processor or central processing unit (CP) can be a structure that detects overcurrent through the shunt resistor SR. When an overcurrent is detected, the monitoring processor or CP can also control the on / off operation of the charge / discharge switch SW by controlling the switch driver SDRV. Figure 1 An example of a structure in which these operations are performed is shown, corresponding to a central processing unit (CP). Furthermore, in this case, the CP can operate to prevent damage to the battery cell C due to overcurrent by detecting an overcurrent flowing through the shunt resistor SR to the battery cell C and controlling the switch driver SDRV to disconnect the charge / discharge switch SW.

[0055] The regulator REG can adjust the voltage level at the uppermost node B+ of multiple battery cells C to a level corresponding to the operating voltage VCC of the central processing unit CP, and the operating voltage VCC of the central processing unit CP can be generated by the regulator REG. The regulator REG can be implemented as a DC / DC converter that converts the voltage at the uppermost node B+ of multiple battery cells C into the operating voltage of the central processing unit CP.

[0056] The fuse device F can be configured to block the current path connected to the battery BAT (i.e., the aforementioned charging / discharging path). Here, blocking the current path can refer to blocking the flow of current by physically cutting off the current path. In this embodiment, the fuse device F includes a fuse element F_UNIT to be ignited and diagnosed, and its peripheral circuitry (drive circuit 10, diagnostic current supply circuit 20, ignition circuit 30, resistance monitoring circuit 40, and switch monitoring circuit 50, see [link]). Figure 3 (and a detailed description thereof is provided below.)

[0057] When battery packs are used in electric vehicles, they typically provide protection functions whereby power to the battery pack is shut off when an impact is detected due to a collision with the electric vehicle. However, in some cases, these protection functions may fail to function properly. When the protection functions fail, a pyrofuse (or pyroswitch) can be provided within the battery pack as a fuse element F_UNIT to block the current path connected to the battery. A pyrofuse is a fuse element F_UNIT that explodes and physically severs the wiring connected to it when a current flows with an amplitude greater than or equal to a threshold defined for its ignition. The fuse element F_UNIT constituting the fuse device F of this disclosure can be implemented as a pyrofuse.

[0058] The circuit configuration and operation of the fuse unit F are described below. The fuse unit F can perform fuse diagnostic operations and fuse ignition operations in an integrated manner, and can also diagnose abnormalities in the diagnostic current supply circuit 20 and ignition circuit 30 applied to the fuse unit F, in addition to the fuse element F_UNIT.

[0059] 2. Fuse assembly

[0060] Figure 2 This is a block diagram illustrating a fuse device according to an embodiment of the present disclosure. Figure 3 This is a circuit diagram illustrating a fuse device according to an embodiment of the present disclosure. Figures 4A to 4C This is an exemplary diagram illustrating the fuse diagnostic operation of a fuse device according to embodiments of the present disclosure, and Figure 5 This is an exemplary diagram illustrating the fuse ignition operation of a fuse apparatus according to embodiments of the present disclosure.

[0061] refer to Figure 2 The fuse device F according to this disclosure may include a fuse element F_UNIT, a drive circuit 10, an ignition circuit 30, a diagnostic current supply circuit 20, a resistance monitoring circuit 40, and a switch monitoring circuit 50. Figure 2In the example depicted, the fuse element F_UNIT is modeled as an internal resistance R_F. The fuse assembly F may include a drive signal input node where a drive signal SIG_DRV for activating drive circuit 10 is input, a first ignition signal input node and a second ignition signal input node where a first ignition signal SIG1_IGN and a second ignition signal SIG2_IGN for activating ignition circuit 30 are input, respectively, and a diagnostic signal input node where a diagnostic signal SIG_DIAG for activating diagnostic current supply circuit 20 is input, serving as signal input nodes. Furthermore, the fuse assembly F may have a first power input node where a first power supply voltage PWR1 is input and a second power input node where a second power supply voltage PWR2 is input, serving as power input nodes. The first power supply voltage PWR1 and the second power supply voltage PWR2 may be a high voltage supplied from the main battery BAT, a low voltage supplied from the auxiliary battery, or a separate voltage (e.g., VCC) generated by regulating the high or low voltage. Furthermore, the fuse unit F may have a first voltage output node that outputs a voltage V_SEN (more precisely, an amplified value of the voltage at both ends) across the fuse element F_UNIT, and a second voltage output node that outputs a voltage V_SW_DIAG formed at the connection node N_B (described later), as output nodes. The voltage V_SEN across the fuse element F_UNIT and the voltage V_SW_DIAG at the connection node N_B can be sent to the processor CP.

[0062] Among the signals input to the fuse unit F, the drive signal SIG_DRV, the first ignition signal SIG1_IGN, and the diagnostic signal SIG_DIAG can be sent from the processor CP, and the second ignition signal SIG2_IGN can be sent from the upper controller CTRLER (i.e., the vehicle's ECU). Here, the first ignition signal SIG1_IGN can correspond to the signal received by the processor CP from the upper controller CTRLER and sent to the fuse unit F when an impact on the vehicle is detected, and the second ignition signal SIG2_IGN can correspond to the signal directly sent to the fuse unit F by the upper controller CTRLER when an impact on the vehicle is detected.

[0063] Reference Figure 3 Describe in detail the sub-components of the fuse device F. Figure 3 In this diagram, only the components required to operate the fuse device F are indicated by reference numerals, while passive components not indicated by reference numerals refer to the lead impedance applied when designing the circuit.

[0064] The fuse element F_UNIT can be implemented using the aforementioned thermal fuse. The fuse element F_UNIT can be configured to explode when a current flows with an amplitude greater than or equal to a threshold defined for ignition, thereby blocking the current path connected to the battery BAT.

[0065] The drive circuit 10 can be configured to allow or block current flow from the first power node to the fuse element F_UNIT. For this purpose, the drive circuit 10 may include a main drive switch M1 and a sub-drive switch M2.

[0066] As an example where the main drive switch M1 and the sub-drive switch M2 are implemented as field-effect transistors (FETs) (N-type), the gate terminal of the sub-drive switch M2 is connected to the second power node via a connecting resistor R11 and a diode D1, wherein diode D1 is connected in the forward direction based on the direction from the second power node to the gate terminal of the sub-drive switch M2, and its source terminal is connected to the ground node. The node N_A to which the gate terminal of the sub-drive switch M2 and the connecting resistor R11 are connected is connected to the drive signal input node via diode D2, wherein diode D2 is connected in the forward direction based on the direction from node N_A to the drive signal input node. The gate terminal of the main drive switch M1 is connected to the drain terminal of the sub-drive switch M2 and the first power node via connecting resistors R12 and R13, respectively. The source terminal of the main drive switch M1 is connected to the first power node, and its drain terminal is connected to the fuse element F_UNIT.

[0067] When battery pack P is in a wake-up / normal state where it operates normally, processor CP can input a high-level drive signal SIG_DRV to the drive signal input node or maintain the drive signal input node in a floating state, and the drive signal input node is electrically disconnected from node N_A through diode D2. Therefore, drive circuit 10 always remains in an active state except when fuse element F_UNIT malfunctions or is short-circuited (described below) and battery pack P is in a turned-off state. Sub-drive switch M2 is turned on by the second power supply voltage PWR2 input from the second power node, whereby current flows from the first power node through the connecting resistors R13, R12 and the drain and source terminals of sub-drive switch M2 to ground node GND. The flowing current and the voltage signal formed by the connecting resistors R13 and R12 are formed at the gate terminal of main drive switch M1. Therefore, main drive switch M1 is turned on, allowing current to flow from the first power node to fuse element F_UNIT. When the local level drive signal SIG_DRV is input from the processor CP to the drive signal input node (i.e., when the drive signal input node is grounded), the current from the second power node discharges through diode D1, connecting resistor R11, and diode D2 through the drive signal input node, causing the voltage level of node N_A to decrease, and the sub-drive switch M2 and main drive switch M1 to open. Therefore, the current flow from the first power node to the fuse element F_UNIT is blocked.

[0068] Therefore, the drive circuit 10 can be used as a high-side switch to drive the current flow to the fuse element F_UNIT by controlling whether the fuse element F_UNIT is conductive. Furthermore, the magnitude of the current flowing through the fuse element F_UNIT is determined by the diagnostic current supply circuit 20 and the ignition circuit 30.

[0069] Next, the diagnostic current supply circuit 20 can be configured to generate a diagnostic current for diagnosing the fuse element F_UNIT. When the diagnostic current flows through the fuse element F_UNIT, the voltage formed across the fuse element F_UNIT can be measured by the resistance monitoring circuit 40 (described below). Therefore, the processor CP can operate to monitor the resistance value of the internal resistance of the fuse element F_UNIT based on the voltage measured by the resistance monitoring circuit 40.

[0070] The diagnostic current supply circuit 20 may include a first switch Q1 and a second switch Q2, a delay circuit 21 and a first resistor R22.

[0071] In the example where the first switch Q1 and the second switch Q2 are implemented as bipolar junction transistors (BJTs) (NPNs), the collector terminal of the first switch Q1 is connected to the fuse element F_UNIT, and its emitter terminal is connected to the ground node through the first resistor R22. The collector terminal of the second switch Q2 is connected to both the fuse element F_UNIT and the collector terminal of the first switch Q1, and its emitter terminal is connected to the base terminal of the first switch Q1. Therefore, the first switch Q1 and the second switch Q2 are cascaded.

[0072] Delay circuit 21 is connected between the diagnostic signal input node and the base terminal of the second switch Q2. Delay circuit 21 may include a second resistor R21 and a capacitor C21 constituting an RC filter. The diagnostic signal SIG_DIAG input through the diagnostic signal input node can be configured to be applied to the base terminal of the second switch Q2 via delay circuit 21. Diagnostic current supply circuit 20 can be configured to receive the second ignition signal SIG2_IGN (described below) together with the diagnostic signal SIG_DIAG. The base terminal of the second switch Q2 is connected to the diagnostic signal input node and the second ignition signal input node via delay circuit 21 in an OR configuration. The OR connection structure can be implemented in which diodes D3 and D4 are connected to the diagnostic signal input node and the second ignition signal input node, respectively, and the cathodes of diodes D3 and D4 are connected together to the base terminal of the second switch Q2 via delay circuit 21. Therefore, the second switch Q2 can be turned on in response to the input of at least one of the diagnostic signal SIG_DIAG and the second ignition signal SIG2_IGN. In other words, the second switch Q2 can be turned on when one or more of the diagnostic signal SIG_DIAG and the second ignition signal SIG2_IGN are at a high level.

[0073] When the high-level diagnostic signal SIG_DIAG is input through the diagnostic signal input node, a voltage level (high level) for the diagnostic signal SIG_DIAG is formed at the base terminal of the second switch Q2 at a time point corresponding to the RC time constant of the delay circuit 21 after the input time point. As will be described below, the time delay of the delay circuit 21 prevents the first switch Q1 and the second switch Q2 from being turned on by temporary noise signals input through the second ignition signal input node. This prevents the fuse element F_UNIT from being ignited and does not affect the diagnostic operation of diagnosing abnormalities of the fuse element F_UNIT by generating a diagnostic current. When the second switch Q2 is turned on, the current flowing from the current collector terminal of the second switch Q2 to the current emitter terminal is input to the base terminal of the first switch Q1 to turn on the first switch Q1. Therefore, the diagnostic current flows along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the first resistor R22, and the ground node (assuming the ignition switch M3 is in the off state, which will be described below).

[0074] Based on the DC analysis of the BJT, the amplitude (i.e., current value) of the diagnostic current flowing through the fuse element F_UNIT is determined by the amplitude (i.e., voltage value) of the base terminal voltage of the first switch Q1 and the resistance value of the first resistor R22 (i.e., (base terminal voltage - threshold voltage) / resistance value of the first resistor R22). Assuming that the base terminal voltage has a fixed value according to the design specifications of the fuse device F, the amplitude of the diagnostic current flowing through the fuse element F_UNIT is determined based on the resistance value of the first resistor R22. Furthermore, since the resistance value of the first resistor R22 is constant, the diagnostic current flowing through the fuse element F_UNIT is a constant current. Therefore, the diagnostic current supply circuit 20 can operate as a constant current supply circuit. The first resistor R22 can have a pre-designed resistance value to limit the diagnostic current so that the fuse element F_UNIT is not ignited by the diagnostic current when the ignition switch M3 is in the open state.

[0075] Since the amplitude of the diagnostic current (i.e., the constant current) is determined solely by the first resistor R22, changes in the resistance value of the internal resistor of the fuse element F_UNIT or changes in the first power supply voltage PWR1 do not affect the amplitude of the diagnostic current. This constant current generation method enables internal resistance monitoring based on the voltage across the terminals using the resistance monitoring circuit 40.

[0076] The ignition circuit 30 can be configured to generate an ignition current for igniting the fuse element F_UNIT. When the ignition current generated by the ignition circuit 30 flows through the fuse element F_UNIT, the fuse element F_UNIT can be ignited and the current path connected to the battery BAT can be blocked. The ignition circuit 30 may include an ignition switch M3 as a switch for generating the ignition current, and the ignition switch M3 may be implemented as a FET (N-type).

[0077] In the connection structure of ignition switch M3, the drain terminal of ignition switch M3 is connected to the emitter terminal of the first switch Q1. Therefore, the first switch Q1 and ignition switch M3 are connected in a common-source, common-gate configuration. For convenience, the node to which the drain terminal of ignition switch M3, the emitter terminal of the first switch Q1, the first resistor R22, and the monitoring resistor R51 (described below) are connected is referred to as connection node N_B. The gate terminal of ignition switch M3 is connected to the first ignition signal input node and the second ignition signal input node in an OR configuration. The OR connection structure can be implemented in which diodes D5 and D6 are respectively connected to the first ignition signal input node and the second ignition signal input node, and the cathodes of diodes D5 and D6 are connected to the gate terminal of ignition switch M3. Therefore, ignition switch M3 can be turned on in response to the input of at least one of the first ignition signal SIG1_IGN and the second ignition signal SIG2_IGN. In other words, the ignition switch M3 can be turned on when one or more of the first ignition signal SIG1_IGN and the second ignition signal SIG2_IGN are at a high level. From the perspective of its connection with the aforementioned drive circuit 10, the ignition circuit 30 can be used as a low-side switch, which drives the current flow to the fuse element F_UNIT by controlling whether the fuse element F_UNIT is conductive.

[0078] When the first switch Q1 of the aforementioned diagnostic current supply circuit 20 is turned on, and when the ignition switch M3 is turned on, an ignition current with an amplitude greater than or equal to a threshold flows along a current path connected to the first power node, fuse element F_UNIT, first switch Q1, ignition switch M3, and ground node. Therefore, fuse element F_UNIT can be ignited. In this case, with the second switch Q2 operating as a current buffer, the current flowing from the current collector terminal of the second switch Q2 to the emitter terminal can be input to the base terminal of the first switch Q1 to turn on the first switch Q1, and the current flowing from the base terminal of the first switch Q1 to the emitter terminal can be formed such that an ignition current with an amplitude equal to or greater than the threshold sufficient to ignite fuse element F_UNIT can be formed. Furthermore, the amplitude of the first power supply voltage PWR1 and the resistance value of the internal resistance of fuse element F_UNIT can be configured to form an ignition current with an amplitude equal to or greater than the threshold. Since the two ends of the first resistor R22, which is connected in parallel with the ignition switch M3, are short-circuited when the ignition switch M3 is turned on, the ignition current does not flow to the first resistor R22, and the ignition current only flows to the ignition switch M3.

[0079] Utilizing the connection structure of the drive circuit 10, the diagnostic current supply circuit 20, and the ignition circuit 30, the diagnostic current supply circuit 20 can generate a diagnostic current regardless of whether the ignition circuit 30 is activated. The diagnostic current generated by the diagnostic current supply circuit 20 is provided independently of the activation of the ignition circuit 30, regardless of whether the ignition switch M3 is on or off. Specifically, even when the ignition circuit 30 is in an inactive state (i.e., the ignition switch M3 is off), the diagnostic current can still be generated by the diagnostic current supply circuit 20.

[0080] Because the drive circuit 10 remains active except when the battery pack P is off or when the fuse element F_UNIT is faulty or short-circuited, when the diagnostic current supply circuit 20 is activated in the inactive state of the ignition circuit 30 (i.e., when the first switch Q1 and the second switch Q2 are on), the diagnostic current flows along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the first resistor R22, and the ground node. Even when the ignition circuit 30 is activated, the diagnostic current can still flow along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the ignition switch M3, and the ground node. In this case, the diagnostic current constitutes part of the ignition current, but since the fuse element F_UNIT is ignited by the ignition current, no diagnostic operation is performed on the fuse element F_UNIT.

[0081] Conversely, the ignition circuit 30 can be configured to generate an ignition current depending on whether the diagnostic current supply circuit 20 is activated. The fact that the ignition current is generated depending on whether the diagnostic current supply circuit 20 is activated means that the ignition current is generated only when the first switch Q1 and the second switch Q2 are turned on.

[0082] Specifically, the drive circuit 10 remains active except in cases where the fuse element F_UNIT malfunctions or is short-circuited and the battery pack P is off. When the diagnostic current supply circuit 20 is deactivated (i.e., when the first switch Q1 and the second switch Q2 are open), the fuse element F_UNIT is not conductive. Therefore, even when the ignition circuit 30 is activated (when the ignition switch M3, connected to the first switch Q1 in a common-source, common-gate configuration, is turned on), the ignition current does not flow in the fuse element F_UNIT. When the diagnostic current supply circuit 20 is activated (when the first switch Q1 and the second switch Q2 are turned on), and when the ignition circuit 30 is activated, the ignition current flows along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the ignition switch M3, and the ground node.

[0083] The connection operation of the diagnostic current supply circuit 20 and the ignition circuit 30 is as follows.

[0084] When the first switch Q1 and the second switch Q2 of the diagnostic current supply circuit 20 are turned on with the sub-drive switch M2 and the main drive switch M1 of the drive circuit 10 on, the diagnostic current flows along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the first resistor R22, and the ground node. As described above, the second switch Q2 of the diagnostic current supply circuit 20 operates as a current buffer, but the amplitude of the diagnostic current is limited by the first resistor R22. Therefore, the fuse element F_UNIT is not ignited by the diagnostic current.

[0085] When ignition switch M3 is turned on, ignition current flows through the current path connected to the first power node, fuse element F_UNIT, first switch Q1, ignition switch M3, and ground node. Since the first resistor R22, connected in parallel with ignition switch M3, is short-circuited when ignition switch M3 is turned on, the current limiting function of the first resistor R22 is eliminated. Therefore, through the second switch Q2, which acts as a current buffer, the ignition current has an amplitude greater than or equal to the threshold, allowing fuse element F_UNIT to be ignited.

[0086] When the first switch Q1, the second switch Q2, and the ignition switch M3 are all off, and when the high-level second ignition signal SIG2_IGN is input through the second ignition signal input node after the impact on the vehicle, the first switch Q1, the second switch Q2, and the ignition switch M3 are all on. In this case, through the delay circuit 21, the first switch Q1 is turned on later than the ignition switch M3; that is, through the delay circuit 21, there is a time difference between the turn-on time of the first switch Q1 and the turn-on time of the ignition switch M3. When the vehicle collision occurs, the second ignition signal SIG2_IGN input through the second ignition signal input node remains at a high level for a period equal to or greater than this time difference. In other words, when there is a vehicle impact, the first switch Q1 is turned on later than the ignition switch M3, but the ignition switch M3 remains on during the turn-on time of the first switch Q1. Therefore, the ignition current flows through the fuse element F_UNIT, allowing the fuse element F_UNIT to be ignited normally.

[0087] The second ignition signal SIG2_IGN may be caused by the impact of a vehicle collision. However, the noise signal may be generated by an impact such as a vehicle door closing. Even when the noise signal of the second ignition signal SIG2_IGN is input, the first switch Q1 is turned on later than the ignition switch M3 through the delay circuit 21. That is, through the delay circuit 21, there is a time difference between the turn-on time of the first switch Q1 and the turn-on time of the ignition switch M3. At this time, the second ignition signal SIG2_IGN / noise signal is high only for a period of time less than this time difference. In other words, since the second ignition signal SIG2_IGN / noise signal is high only for a very short time, the ignition switch M3 remains off when the first switch Q1 is turned on. Therefore, when the second ignition signal SIG2_IGN / noise signal is input, the delay circuit 21 prevents the first switch Q1 and the ignition switch M3 from turning on, thereby preventing the fuse element F_UNIT from being accidentally ignited. The RC time constant of the delay circuit 21 used to implement the above operation can be pre-designed based on experimental results.

[0088] The resistance monitoring circuit 40 can be connected to the fuse element F_UNIT to monitor the resistance value of the internal resistance of the fuse element F_UNIT. The resistance monitoring circuit 40 may include an amplifier AMP that amplifies the voltage V_SEN across the fuse element F_UNIT. The output terminal of the amplifier AMP is connected to a voltage output node, and the amplifier AMP can be implemented as an operational amplifier OP-AMP.

[0089] The resistance monitoring circuit 40 can operate in conjunction with the diagnostic current supply circuit 20. That is, the resistance monitoring circuit 40 can measure the voltage V_SEN across the fuse element F_UNIT when the diagnostic current generated by the diagnostic current supply circuit 20 flows through the fuse element F_UNIT.

[0090] As described above, because the diagnostic current is a constant current, the change in voltage V_SEN across the fuse element F_UNIT depends only on the change in the internal resistance of the fuse element F_UNIT. Therefore, the processor CP can calculate the internal resistance of the fuse element F_UNIT based on the voltage V_SEN across the fuse element F_UNIT and the amplitude of the diagnostic current (i.e., the amplitude of a constant current that can be predefined in the processor CP). Furthermore, when the calculated resistance value is outside a preset reference range, the processor CP can determine that an anomaly has occurred in the fuse element F_UNIT. The reference range corresponds to the resistance value that indicates no anomaly or degradation has occurred in the fuse element F_UNIT. The reference range can be predefined in the processor CP based on intent and experimental results.

[0091] Figures 4A to 4C The amplitude of the diagnostic current and the amplitude of the voltage across the internal resistor are shown, based on the resistance value of the fuse element F_UNIT. The amplitudes of the diagnostic current are summarized in Table 1 below (where the values ​​are approximate). Figures 4A to 4C In this context, SIG_DIAG refers to the diagnostic signal, I_DIAG refers to the diagnostic current, and V_SEN refers to the voltage across the fuse element F_UNIT.

[0092] Table 1

[0093]

[0094] like Figures 4A to 4C As shown in Table 1, even when the internal resistance of the fuse element F_UNIT changes, the amplitude of the diagnostic current (quiescent current) remains constant at 100 mA. Furthermore, since the amplitude of the diagnostic current remains constant, it can be concluded that the change in the internal resistance of the fuse element F_UNIT is represented by the change in the voltage V_SEN across the fuse element F_UNIT. For example, refer to... Figures 4A to 4C When the internal resistance of the fuse element F_UNIT increases to 1Ω, 1.7Ω, and 3Ω, the voltage V_SEN across the fuse element F_UNIT increases to 0.7V, 1.2V, and 2.1V, respectively. In other words, as the diagnostic current becomes a constant current, abnormalities in the fuse element F_UNIT can be easily detected by simply measuring the voltage V_SEN across its terminals.

[0095] Next, the switch monitoring circuit 50 can be used to monitor for abnormalities or deterioration of the first switch Q1 and the ignition switch M3. For this purpose, the switch monitoring circuit 50 may include a monitoring resistor R51 connected between the second power node and the connection node N_B. The monitoring resistor R51 can be connected to the second power node via a diode D7.

[0096] The magnitude of the voltage V_SW_DIAG formed at the connection node N_B can be configured to vary depending on whether the first switch Q1 and the ignition switch M3 are in the on or off state. Figure 5 Table 2 below shows an example of the voltage V_SW_DIAG formed at connection node N_B based on the on or off state of each switch when both the first switch Q1 and the ignition switch M3 are functioning normally (i.e., when degradation of each switch has not yet occurred). Figure 5 In the diagram, V_SW_DIAG refers to the voltage of the connection node N_B, SIG_DIAG and SIG1_IGN refer to the diagnostic signal and the first ignition signal, respectively, and I_FUSE refers to the current flowing through the fuse element F_UNIT.

[0097] Table 2

[0098]

[0099] When both the first switch Q1 and the ignition switch M3 are open, current flows through the current path connected to the second power node, diode D7, monitoring resistor R51, first resistor R22, and ground node. Therefore, a voltage of 1.1V is formed in the connection node N_B by the voltage division of the monitoring resistor R51 and the first resistor R22.

[0100] When the first switch Q1 and the ignition switch M3 are turned on and off respectively, a diagnostic current of 0.1A flows along the current path connected to the first power node, fuse element F_UNIT, first switch Q1, first resistor R22, and ground node. Furthermore, through the diagnostic current and the first resistor R22, a voltage of 2V is formed at the connection node N_B.

[0101] When both the first switch Q1 and the ignition switch M3 are turned on, no abnormality monitoring operation is performed on the first switch Q1 and the ignition switch M3 because the fuse element F_UNIT is ignited. Table 2 shows the values ​​obtained by analyzing the circuit operation in this regard.

[0102] When the first switch Q1 and the ignition switch M3 are respectively open and closed, the connection node N_B is connected to the ground node through the ignition switch M3 to form a 0V voltage.

[0103] The processor CP can detect anomalies in the first switch Q1 and the ignition switch M3 by monitoring the amplitude of the voltage formed at the connection node N_B. A detailed description will be provided below.

[0104] 3. BMS fuse control operation

[0105] In the following text, based on the above-described circuit structure of the fuse device F, the operation of the processor CP of the battery management system BMS for diagnosing abnormalities of the fuse element F_UNIT, the operation of igniting the fuse element F_UNIT, and the operation of diagnosing abnormalities of the first switch Q1 and the ignition switch M3 will be described in detail.

[0106] When performing a fuse diagnostic operation, the processor CP can input a high-level drive signal SIG_DRV to the drive signal input node or maintain the drive signal input node in a floating state to activate the drive circuit 10. Therefore, the sub-drive switch M2 and the main drive switch M1 are sequentially turned on, allowing current to flow from the first power node to the fuse element F_UNIT. Simultaneously, the processor CP can disable the ignition circuit 30 by inputting a low-level first ignition signal SIG1_IGN to the first ignition signal input node, and can activate the diagnostic current supply circuit 20 by inputting a high-level diagnostic signal SIG_DIAG to the diagnostic signal input node. Therefore, the first switch Q1 and the second switch Q2 are turned on, allowing diagnostic current to flow along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the first resistor R22, and the ground node.

[0107] As described above, the diagnostic current flowing through the fuse element F_UNIT is a constant current with a predefined amplitude based on the resistance value of the first resistor R22. Since the amplitude of the diagnostic current (i.e., the constant current) is determined solely by the first resistor R22, changes in the resistance value of the internal resistance of the fuse element F_UNIT do not affect the amplitude of the diagnostic current. The amplitude of the constant current flowing through the fuse element F_UNIT can be predefined in the processor CP.

[0108] When diagnostic current flows through fuse element F_UNIT, processor CP can monitor the internal resistance value of fuse element F_UNIT via resistance monitoring circuit 40. Specifically, processor CP can monitor the internal resistance value of fuse element F_UNIT by calculating the internal resistance value based on the voltage V_SEN at both ends of fuse element F_UNIT identified by resistance monitoring circuit 40 and the amplitude of diagnostic current (constant current).

[0109] When the internal resistance of fuse element F_UNIT is outside a preset reference range, the processor CP can determine that an anomaly has occurred in fuse element F_UNIT. The reference range corresponds to the resistance value that determines that no anomaly or degradation has occurred in fuse element F_UNIT. The reference range can be predefined in the processor CP based on intent and experimental results.

[0110] When an anomaly is detected in fuse element F_UNIT, the processor CP can control the drive circuit 10 to block the current flow from the first power node to fuse element F_UNIT. That is, the processor CP can disable the drive circuit 10 by inputting a low-level drive signal SIG_DRV to the drive signal input node (i.e., by grounding the drive signal input node). Therefore, additional damage to fuse element F_UNIT can be prevented, which could otherwise be caused by the continuous current applied from the first power node to fuse element F_UNIT even if an anomaly occurs in it.

[0111] Furthermore, the processor CP can determine whether the fuse element F_UNIT is short-circuited based on the voltage V_SEN across the fuse element F_UNIT identified by the resistance monitoring circuit 40. When a short circuit is detected in the fuse element F_UNIT, the control drive circuit 10 blocks the current flow from the first power node to the fuse element F_UNIT. That is, the processor CP can determine that the fuse element F_UNIT is short-circuited when the voltage V_SEN across the fuse element F_UNIT identified by the resistance monitoring circuit 40 has a value of 0, and the processor CP can input a low-level drive signal SIG_DRV to the drive signal input node to disable the drive circuit 10 when a short circuit is detected in the fuse element F_UNIT. Therefore, damage to the fuse device F, which could otherwise be caused by the continuous flow of current through the short circuit, can be prevented.

[0112] When performing a fuse ignition operation, the processor CP can input a high-level drive signal SIG_DRV to the drive signal input node or maintain the drive signal input node in a floating state to activate the drive circuit 10. Therefore, the sub-drive switch M2 and the main drive switch M1 are sequentially turned on, allowing current to flow from the first power node to the fuse element F_UNIT. Simultaneously, the processor CP can activate the ignition circuit 30 by inputting a high-level first ignition signal SIG1_IGN to the first ignition signal input node, and the processor CP can activate the diagnostic current supply circuit 20 by inputting a high-level diagnostic signal SIG_DIAG to the diagnostic signal input node. Therefore, the ignition current can flow along the current path connected to the first power node, the fuse element F_UNIT, the first switch Q1, the ignition switch M3, and the ground node. Thus, the fuse element F_UNIT can be ignited. Even when a high-level second ignition signal SIG2_IGN (excluding noise signals) is input from the upper controller CTRLER to the second ignition signal input node, the above fuse ignition operation is performed in the same manner.

[0113] Independent of the aforementioned fuse diagnostic and ignition operations, the processor CP can monitor anomalies in the first switch Q1 and ignition switch M3 by monitoring the amplitude of the voltage V_SW_DIAG formed at the connection node N_B (i.e., the node where the emitter terminal of the first switch Q1, the drain terminal of the ignition switch M3, and the first resistor R22 and the monitoring resistor R51 are all connected). As mentioned above, the amplitude of the voltage V_SW_DIAG formed at the connection node N_B can vary depending on whether the first switch Q1 and the ignition switch M3 are in the ON or OFF state.

[0114] Therefore, the processor CP can obtain the voltage V_SW_DIAG formed at the connection node N_B through the second voltage output node in each of the following cases: i) both the first switch Q1 and the ignition switch M3 are off; ii) the first switch Q1 and the ignition switch M3 are on and off respectively; and iii) the first switch Q1 and the ignition switch M3 are off and on respectively. Furthermore, when the obtained voltage differs from the predefined reference voltage shown in Table 2, it can be determined that an anomaly has occurred in at least one of the first switch Q1 and the ignition switch M3.

[0115] As described above, according to this disclosure, a diagnostic and ignition mechanism can be provided to perform a fuse diagnostic operation by measuring the internal resistance of the fuse element by measuring the voltage V_SEN at both ends of the fuse element while a diagnostic current (constant current) for diagnosing the fuse element flows through the fuse element, and the mechanism can perform a fuse ignition operation by igniting the fuse element by allowing an ignition current for ignition of the fuse element to flow through the fuse element.

[0116] Furthermore, according to this disclosure, a circuit topology capable of diagnosing abnormalities in the diagnostic current supply circuit and ignition circuit required for diagnosing and igniting fuse elements can be provided.

[0117] The implementations described in this specification can be implemented as, for example, methods or procedures, apparatus, software programs, data streams, or signals. Even if described only in the context of a single form of implementation (e.g., describing only a method), the described features can also be implemented in other forms (e.g., apparatus or program). Apparatus can be implemented with appropriate hardware, software, firmware, etc. Methods can be implemented by apparatuses such as processors, which are typically processing apparatuses including computers, microprocessors, integrated circuits, or programmable logic devices. Processors can include communication devices such as computers, cellular phones, portable / personal digital assistants (PDAs), and other devices that facilitate information communication between end users.

[0118] The effects achievable through this disclosure are not limited to those described above, and other effects not described will be clearly understood by those skilled in the art from the detailed description.

[0119] Although this disclosure has been described with reference to embodiments and accompanying drawings illustrating various aspects of this disclosure, this disclosure is not limited thereto. Various modifications and variations can be made by those skilled in the art within the scope of the technical spirit of this disclosure.

Claims

1. A fuse device, comprising: A fuse element is configured to block the current path connected to the battery; A diagnostic current supply circuit is connected to the fuse element and configured to allow diagnostic current for diagnosing the fuse element to flow through the fuse element; and An ignition circuit, connected to the diagnostic current supply circuit and configured to allow ignition current for igniting the fuse element to flow through the fuse element. The diagnostic current supply circuit is configured to generate the diagnostic current regardless of whether the ignition circuit is activated, and the ignition circuit is configured to generate the ignition current depending on whether the diagnostic current supply circuit is activated.

2. The fuse device according to claim 1, wherein, The ignition circuit includes an ignition switch configured to turn on in response to an input of at least one of a first ignition signal and a second ignition signal to generate the ignition current in the fuse element, and The first processor is configured to apply the first ignition signal to control the operation of the fuse device, and the second processor is configured to apply the second ignition signal, wherein the second processor serves as a host controller for the first processor.

3. The fuse device according to claim 2, wherein, The diagnostic current supply circuit includes a switch and a resistor. The switch is connected to the ignition switch in a common-source, common-gate configuration and is configured to turn on in response to a diagnostic signal input. The resistor is connected to the ignition switch and to the connection node to which the switch is connected. When the switch is turned on, the diagnostic current is configured to flow along a current path connected to the fuse element, the switch, the resistor, and the ground node.

4. The fuse device according to claim 3, wherein, The diagnostic current is a constant current having an amplitude determined by the resistance value of the resistor.

5. The fuse device according to claim 3, wherein, When both the ignition switch and the switch are turned on, the ignition current is configured to flow along a current path connected to the fuse element, the switch, the ignition switch and the ground node.

6. The fuse device according to claim 3, wherein, The switch is configured to turn on in response to the input of at least one of the diagnostic signal and the second ignition signal, and The diagnostic current supply circuit further includes a delay circuit, which is configured to delay the switching time relative to the time when the diagnostic signal or the second ignition signal is input.

7. The fuse device according to claim 6, wherein, The switch is the first switch, and The diagnostic current supply circuit further includes a second switch, which is cascaded to the first switch and configured to turn on the first switch in response to the input of the diagnostic signal or the second ignition signal.

8. The fuse device according to claim 1, further comprising: The drive circuit is configured to allow or block the flow of current from the first power node to which the first power supply voltage is applied to the fuse element; and A resistance monitoring circuit is configured to monitor the resistance value of the internal resistance of the fuse element based on the voltage across the two ends of the fuse element.

9. The fuse device according to claim 8, wherein, When the resistance value of the internal resistance of the fuse element, as monitored by the resistance monitoring circuit, is outside a preset range, the drive circuit is configured to block the current flow to the fuse element.

10. The fuse device according to claim 3, further comprising a switch monitoring circuit, the switch monitoring circuit including a monitoring resistor connected between a second power node to which a second power supply voltage is applied and the connection node, for monitoring abnormalities of the switch and the ignition switch.

11. The fuse device according to claim 10, wherein, The magnitude of the voltage formed at the connection node is configured to vary depending on whether the switch and the ignition switch are in the on or off state.

12. A battery management system, comprising: A fuse element is configured to block the current path connected to the battery; A diagnostic current supply circuit is connected to the fuse element and configured to allow diagnostic current for diagnosing the fuse element to flow through the fuse element; An ignition circuit, connected to the diagnostic current supply circuit and configured to allow ignition current for ignition of the fuse element to flow through the fuse element; and The processor is configured to (i) diagnose the fuse element by disabling the ignition circuit and activating the diagnostic current supply circuit to generate the diagnostic current, and (ii) ignite the fuse element by activating both the diagnostic current supply circuit and the ignition circuit to generate the ignition current.

13. The battery management system according to claim 12, wherein, The ignition circuit includes an ignition switch configured to turn on in response to an input of at least one of a first ignition signal and a second ignition signal to generate the ignition current in the fuse element, and The diagnostic current supply circuit includes a switch and a resistor. The switch is connected to the ignition switch in a common-source, common-gate configuration and is configured to turn on in response to an input diagnostic signal. The resistor is connected to the ignition switch and to the connection node to which the switch is connected.

14. The battery management system according to claim 12, further comprising: The drive circuit is configured to allow or block the flow of current from the first power node to which the first power supply voltage is applied to the fuse element; and A resistance monitoring circuit is configured to monitor the resistance value of the internal resistance of the fuse element. When monitoring the resistance value of the internal resistance of the fuse element, the processor is configured to control the drive circuit to allow current to flow from the first power node to the fuse element.

15. The battery management system according to claim 14, wherein, When monitoring the resistance value of the internal resistance of the fuse element, the processor is configured to (i) control the diagnostic current supply circuit to allow the diagnostic current to flow through the fuse element, and (ii) monitor the resistance value of the internal resistance of the fuse element via the resistance monitoring circuit while the diagnostic current flows through the fuse element.

16. The battery management system according to claim 15, wherein, The processor is configured to monitor the resistance value of the internal resistance of the fuse element based on the voltage at both ends of the fuse element identified by the resistance monitoring circuit and the amplitude of the diagnostic current.

17. The battery management system according to claim 15, wherein, The processor is configured to determine that an abnormality has occurred in the fuse element when the resistance value of the internal resistance of the fuse element, as monitored by the resistance monitoring circuit, is outside a preset range, and to block the current flow from the first power node to the fuse element via the drive circuit.

18. The battery management system according to claim 15, wherein, The processor is configured to determine whether the fuse element is short-circuited based on the voltage across the fuse element identified by the resistance monitoring circuit, and when a short circuit is detected in the fuse element, the processor is configured to control the drive circuit to block the current flow from the first power node to the fuse element.

19. The battery management system according to claim 13, further comprising: A switch monitoring circuit, comprising a monitoring resistor connected between a second power node to which a second power supply voltage is applied and the connection node, is provided to monitor for abnormalities in the switch and the ignition switch. The processor is configured to monitor for abnormalities in the switch and the ignition switch by monitoring the amplitude of the voltage formed at the connection node. The amplitude of the voltage formed at the connection node is configured to vary depending on whether the switch and the ignition switch are in an on or off state.

20. A battery pack, comprising: Battery; A fuse element is configured to block the current path connected to the battery; A diagnostic current supply circuit is connected to the fuse element and configured to allow diagnostic current for diagnosing the fuse element to flow through the fuse element; An ignition circuit, connected to the diagnostic current supply circuit and configured to allow ignition current for ignition of the fuse element to flow through the fuse element; and The processor is configured to (i) diagnose the fuse element by disabling the ignition circuit and activating the diagnostic current supply circuit to generate the diagnostic current, and (ii) ignite the fuse element by activating both the diagnostic current supply circuit and the ignition circuit to generate the ignition current.

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