voltage monitoring circuit

Abstract

The voltage monitoring circuit according to an embodiment of the present application includes a clamping unit for clamping a voltage of input power supplied from a power source to a reference voltage and outputting to an MCU, and a switching unit for cutting off the input power from the power source when the reference voltage of the clamping unit is abnormal.

Description

Technical Field

[0001] This invention relates to a voltage monitoring circuit, and more specifically, to a voltage monitoring circuit, an overcurrent protection circuit, and an overcurrent protection method. When an abnormality occurs in the reference voltage used for voltage monitoring, the voltage monitoring circuit blocks the monitored input power. The overcurrent protection circuit is used to protect the control unit from overcurrent by limiting the output voltage. Background Technology

[0002] The vehicle not only needs to use the power of the battery installed in the vehicle to operate the vehicle's motor, but also needs to provide stable voltage for communication drivers, sensors and various controllers.

[0003] The voltage output from the battery may vary depending on the vehicle type, such as a small or large vehicle, and may also change depending on the battery power source used. However, regardless of the magnitude of the battery output voltage, it must provide the stable voltage required by the various devices within the vehicle.

[0004] At this point, a voltage monitoring circuit is used to detect and monitor the actual output voltage level of the battery. If the actual output voltage of the battery is outside the preset range, or if the circuit monitoring the battery voltage malfunctions, it is necessary to prevent other components connected to the voltage monitoring circuit from malfunctioning.

[0005] Furthermore, if an overcurrent occurs while receiving power from the battery power source, it could damage the vehicle's circuitry or components. To prevent such damage, the control unit monitors the current input from the battery power source. However, in the event of a significant overcurrent, a problem arises when the control unit measures the current input from the battery power source; the control unit itself, which measures this current, could also be damaged.

[0006] Therefore, there is a need for an overcurrent protection circuit that can safely measure current and protect internal circuits or components even when an overcurrent occurs. Summary of the Invention

[0007] Technical goals

[0008] The technical problem to be solved by the present invention is to provide a voltage monitoring circuit that blocks the monitored input power when the reference voltage used for voltage monitoring becomes abnormal.

[0009] In addition, another technical problem to be solved by the present invention is to provide an overcurrent protection circuit that detects current and limits output voltage to protect the control unit from the effects of overcurrent.

[0010] The problems of this invention are not limited to those described above, and those skilled in the art will clearly understand other unmentioned problems through the following description.

[0011] Technical solution

[0012] To solve the above-mentioned technical problems, the voltage monitoring circuit of the embodiment of the present invention includes: a clamping unit that clamps the voltage of the input power input from the power source to a reference voltage and outputs it to the MCU; and a switching unit that blocks the input power from the power source when the reference voltage of the clamping unit is abnormal.

[0013] In addition, the clamping unit can receive a reference voltage with a predetermined voltage level from the voltage supply unit.

[0014] In addition, the switching unit can block the input power from the power source to prevent the power source from being applied to the voltage supply unit.

[0015] In addition, the voltage monitoring circuit may also include a voltage divider unit connected to the front end of the clamping unit to divide the voltage of the input power.

[0016] In addition, the voltage monitoring circuit may also include a low-pass filter connected to the front end of the clamping unit to filter the input power.

[0017] In addition, the switching unit can be composed of transistors or MOSFETs.

[0018] In addition, the power source can be battery power.

[0019] To solve the above-mentioned technical problems, a voltage monitoring circuit according to another embodiment of the first embodiment of the present invention is characterized by comprising: a first power source input unit and a second power source input unit, which receive battery power; a first switching unit connected to the first power input unit and a second switching unit connected to the second power input unit; a first clamping unit for clamping the voltage of the input power input through the first power input unit and the first switching unit to a reference voltage; and a second clamping unit for clamping the voltage of the input power input through the second power input unit and the second switching unit to a reference voltage, wherein when the reference voltage of the first clamping unit is abnormal, the first switching unit blocks the input power from the first power input unit, and wherein when the reference voltage of the second clamping unit is abnormal, the second switching unit blocks the input power from the second power input unit.

[0020] In addition, the first clamping unit and the second clamping unit can receive a reference voltage with a predetermined voltage level from the voltage supply unit through separate connection lines.

[0021] Furthermore, the first switching unit is configured as a transistor, and the second switching unit can be configured as a MOSFET.

[0022] Furthermore, the first switching unit is configured as a MOSFET, and the second switching unit can be configured as a transistor.

[0023] Furthermore, by comparing the voltage clamped in the first clamping unit with the voltage clamped in the second clamping unit, it is determined whether the reference voltage of the first clamping unit or the reference voltage of the second clamping unit is abnormal; and when the reference voltage of the first clamping unit or the reference voltage of the second clamping unit is abnormal, the first switching unit or the second switching unit connected to the clamping unit with the abnormal reference voltage can be turned off.

[0024] In addition, the first clamping unit and the second clamping unit can output the clamping voltage to the MCU.

[0025] To address the aforementioned technical problems, a voltage monitoring circuit according to another embodiment of the first embodiment of the present invention is characterized by comprising: a plurality of power input units receiving battery power; a plurality of switching units connected to each of the plurality of power source input units; and a plurality of clamping units connected to each of the plurality of switching units, clamping the voltage of the input power input through the power input units and the switching units to a reference voltage, wherein the switching units are configured as different types of switches and block input power from the power input unit connected to the clamping unit where the reference voltage of the plurality of power input units is abnormal.

[0026] To address other technical issues, the overcurrent protection circuit according to the second embodiment of the present invention includes: a current detection unit for detecting current input from a power source; a voltage detection unit for detecting a first voltage output from the current detection unit, outputting the first voltage to a control unit when the first voltage is less than a second voltage, and outputting the second voltage to the control unit when the first voltage is greater than or equal to the second voltage; and a control unit for determining whether an overcurrent has been input based on the amplitude of the voltage input from the voltage detection unit.

[0027] Furthermore, when a second voltage is input, the control unit determines that an overcurrent has occurred and can block the power source input from the power source.

[0028] In addition, a switch may be included to block the power source input from the power source.

[0029] In addition, when an overcurrent is detected, the control unit can turn off the switch to block the power source input from the power source.

[0030] In addition, the control unit may include a charge pump that converts the voltage of the control signal to a switch.

[0031] In addition, the current sensing unit may include a current mirror circuit or a shunt resistor.

[0032] Furthermore, the amplitude of the current detected by the current detection unit can be proportional to the amplitude of the voltage output based on the detected current.

[0033] To address other technical problems, an overcurrent protection method according to another embodiment of the second embodiment of the present invention includes the following steps: detecting a first voltage output from a current detection unit, the current detection unit detecting a current applied from a power source; comparing the first voltage with a second voltage; when the first voltage is less than the second voltage, inputting the first voltage to a control unit; when the first voltage is equal to or greater than the second voltage, inputting the second voltage to the control unit; and, when the second voltage is input, determining that an overcurrent has occurred.

[0034] In addition, the method may include the following steps: when it is determined that an overcurrent has occurred, blocking the power source input from the power source.

[0035] In addition, the current sensing unit can be a current mirror circuit or a shunt resistor.

[0036] Beneficial effects

[0037] According to embodiments of the present invention, when the clamping reference voltage of the PMIC becomes abnormal, a fault can be prevented by blocking power sources to other components connected to the PMIC. Furthermore, by implementing the switches as different devices, the possibility of simultaneous dependent failures can be reduced. By receiving the PMIC clamping reference voltage on separate lines, a safety mechanism can be implemented by comparing battery voltages in the event of a line failure.

[0038] In addition, it can prevent damage to components such as control units or inverters due to overcurrent.

[0039] The effects of the invention are not limited to the examples described above, and many more different effects are included in this specification. Attached Figure Description

[0040] Figure 1 This is a block diagram of a voltage monitoring circuit according to an embodiment of the first embodiment of the present invention.

[0041] Figure 2 and Figure 3 This is a block diagram of a voltage monitoring circuit according to another embodiment of the first embodiment of the present invention.

[0042] Figures 4 to 11 This is a diagram used to explain the operation of the voltage monitoring circuit according to the first embodiment of the present invention.

[0043] Figure 12 This is a block diagram of an overcurrent protection circuit according to an embodiment of the second embodiment of the present invention.

[0044] Figure 13 This is a block diagram of an overcurrent protection circuit according to another embodiment of the second embodiment of the present invention.

[0045] Figure 14 This is a diagram used to explain the operation of the overcurrent protection circuit according to the second embodiment of the present invention.

[0046] Figure 15 A comparative example of an overcurrent protection circuit according to an embodiment of the second embodiment of the present invention is shown.

[0047] Figure 16 and Figure 17 The illustrated embodiment implements an overcurrent protection circuit according to an embodiment of the second embodiment of the present invention.

[0048] Figure 18 This is a flowchart of an overcurrent protection method according to an embodiment of the second embodiment of the present invention.

[0049] Figure 19 This is a flowchart of an overcurrent protection method according to another embodiment of the second embodiment of the present invention. Detailed Implementation

[0050] Preferred embodiments of the invention will be described in detail below with reference to the accompanying drawings.

[0051] However, the technical concept of the present invention is not limited to the embodiments described, and can be implemented in various forms. Furthermore, within the scope of the technical concept of the present invention, one or more of the constituent elements can be selectively combined or substituted among the embodiments.

[0052] Furthermore, unless explicitly defined and described, the terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted in accordance with the meaning commonly understood by those skilled in the art, and commonly used terms (such as those defined in dictionaries) may be interpreted taking into account their meaning in the relevant technical context.

[0053] Furthermore, the terminology used in this specification is for the purpose of describing embodiments and is not intended to limit the invention.

[0054] In this specification, unless specifically stated in the phrase, the singular form may include the plural form, and when described as “at least one (or more than one) of A, B, and C”, it may include one or more of all combinations that can be formed from A, B, and C.

[0055] Furthermore, terms such as first, second, A, B, (a), and (b) may be used to describe components of embodiments of the present invention. These terms are intended only to distinguish components from other components, and the nature, order, or sequence of these components are not limited by these terms.

[0056] Furthermore, when a component is described as being “connected,” “coupled,” or “interconnected” to another component, the component is not only directly connected, coupled, or interconnected to the other component, but may also include cases where other components are “connected,” “coupled,” or “interconnected” to the other component.

[0057] Furthermore, when described as being formed or arranged "above" or "below" each component, "above" or "below" means not only the case where two components are in direct contact, but also the case where one or more other components are formed or arranged between the two components. Additionally, when expressed as "above" or "below," it can include not only the meaning of an upward direction based on a component, but also the meaning of a downward direction.

[0058] according to Figure 1 The voltage monitoring circuit 110 in the first embodiment of the present invention includes a clamping unit 111 and a switching unit 112, and may also include a voltage divider unit 113 and a low-pass filter 114.

[0059] Clamping unit 111 clamps the voltage of the input power from power source 120 to the reference voltage.

[0060] More specifically, the voltage level of the input power from the power source 120 input to the clamping unit 111 is clamped to a reference voltage. Here, clamping means fixing the input signal to a specific DC level, and when the amplitude of the voltage of the input power input from the power source 120 is greater than the reference voltage, the amplitude of the input power voltage is limited to the reference voltage.

[0061] The input power to clamping unit 111 can be battery power 120. Since the voltage of battery power 120 is not constant, it needs to be monitored. For this purpose, a voltage monitoring circuit 110 is required to monitor the voltage level of battery power 120. Battery power 120 is used as an example; naturally, the voltage levels of various other powers 120 can also be measured. The following description will be based on input power received from battery power 120.

[0062] Clamping unit 111 can output a clamping voltage to MCU 140. The voltage clamped to a reference voltage in clamping unit 111 can be output to MCU 140 for voltage monitoring. Microcontroller Unit 140 receives the clamping voltage from clamping unit 111 and monitors the voltage of power source 120. MCU 140's ADC module can receive voltages from 0 to 5V to calculate the battery voltage. In this way, the Electronic Control Unit (ECU) can detect failures by monitoring the battery voltage, thereby implementing a functional safety mechanism.

[0063] Clamping unit 111 limits the input power from power source 120 to MCU 140 to a reference voltage. This is because if a voltage greater than the reference voltage is input to MCU 140, the circuitry or ADC module in the MCU that detects that voltage may be damaged. Therefore, to protect the circuitry or module from potential damage, clamping unit 111 clamps the input power voltage to the reference voltage. Clamping unit 111 performs the function of protecting the circuitry.

[0064] Clamping unit 111 can receive a reference voltage with a predetermined voltage level from voltage supply unit 130. The reference voltage is required to clamp the voltage of the input power. Based on this reference voltage, the voltage of the input power that is higher than the reference voltage can be reduced to the reference voltage. The reference voltage can vary depending on the voltage to be clamped. The voltage to be clamped can vary according to safety specifications or device specifications. For example, the reference voltage can be 5V.

[0065] Voltage supply unit 130 supplies a reference voltage for clamping the input power voltage in clamping unit 111. Voltage supply unit 130 may include a power management integrated circuit (PMIC). The reference voltage may be the voltage supplied from voltage supply unit 130 to other components. That is, the voltage supplied to other components can be used as a reference voltage for clamping.

[0066] When the reference voltage of the clamping unit 111 is abnormal, the switching unit 112 blocks the input power from the power source 120.

[0067] More specifically, when the reference voltage of clamping unit 111 becomes abnormal, switching unit 112 blocks the input power, preventing the input power from being input. As mentioned above, the reference voltage of clamping unit 111 can be supplied from voltage supply unit 130. However, when the connection line receiving the reference voltage from voltage supply unit 130 or voltage supply unit 130 experiences an abnormality such as failure, clamping unit 111 may have difficulty receiving a stable reference voltage from voltage supply unit 130. When the reference voltage cannot be stably supplied, the clamping of the input power voltage may also become abnormal. Therefore, the voltage monitoring circuit may fail to operate properly, potentially leading to a malfunction. To prevent malfunctions in the voltage monitoring circuit or other circuits or devices connected to the voltage monitoring circuit, switching unit 112 blocks the input power from power source 120 when the reference voltage becomes abnormal. By blocking the input power, malfunctions caused by unclamped input power can be prevented.

[0068] Switching unit 112 can block input power from power source 120 to prevent power from being applied to voltage supply unit 130. When clamping unit 111 receives a reference voltage from voltage supply unit 130 and the reference voltage is abnormal, if the reference voltage is not normally supplied, the input power input to clamping unit 111 may affect voltage supply unit 130 through clamping unit 111. Voltage supply unit 130 not only supplies the reference voltage to clamping unit 111, but can also supply voltages corresponding to the reference voltage to other components. When voltage supply unit 130 includes a PMIC, it can supply voltage to other components such as CAN ICs performing CAN communication and sensors, and when voltage supply unit 130 does not normally supply voltage, input power may be applied to voltage supply unit 130 through clamping unit 111, thereby affecting other components connected to voltage supply unit 130. When the input power voltage is greater than the voltage already supplied by voltage supply unit 130, overvoltage may be applied to other components, and failure may occur. When the input power is battery power, the battery voltage may fluctuate instead of remaining constant. Therefore, when the input power voltage fluctuates, other components will also be affected. When the corresponding component is one performing communication, errors may occur during communication, potentially leading to significant safety issues.

[0069] For example, if it affects the CAN IC, normal CAN communication may fail. CAN communication is a communication method used in automobiles and other applications, and it represents 0 or 1 based on 0V or 5V. If 5V, representing 1, is already being transmitted from the voltage supply unit 130, and a voltage other than 5V or a voltage fluctuation is input from the input power instead of the voltage supply unit 130, the corresponding voltage may be determined as 0 instead of 1, and normal communication may become difficult. Furthermore, when the 5V voltage supplied to the voltage supply unit 130, such as a pressure sensor or temperature sensor, becomes abnormal, accurate sensing may become difficult, and other operations based on the sensing information may malfunction.

[0070] To prevent failure of other components as described above, when an abnormality occurs in the reference voltage, the switching unit 112 blocks the input power from the power source 120.

[0071] Voltage divider unit 113 can be connected to the front end of clamping unit 111 to divide the voltage of the input power. Voltage divider unit 113 can divide the input voltage to output a constant voltage. Low-pass filter 114 can be connected to the front end of clamping unit 111 to filter the input power. Low-pass filter 114 can remove noise from the input power to output a stable voltage. Voltage divider unit 113 and low-pass filter 114 can be connected sequentially to the front end of clamping unit 111 and can be used to deliver stable input power to clamping unit 111.

[0072] The switching unit 112 can be configured as a transistor or a MOSFET.

[0073] A transistor is a semiconductor device used to amplify or switch electronic signals and power using semiconductors such as germanium (Ge) and silicon (Si). A transistor consists of a collector, an emitter, and a base. Based on the characteristics of the semiconductors forming each configuration, transistors are classified as NPN transistors or PNP transistors. When a forward voltage is applied between the emitter and base, current flows through the collector, and using this operating principle, a transistor can be used as a switch.

[0074] A MOSFET is a metal-oxide-semiconductor field-effect transistor, consisting of a source, a drain, and a gate. Depending on the characteristics of the semiconductor device used, MOSFETs can be classified as NMOS or PMOS. When a voltage is applied to the gate, a channel is formed between the source and drain, allowing current to flow through this channel. Therefore, using this operating principle, a MOSFET can be used as a switch.

[0075] According to another embodiment of the first embodiment of the present invention, the voltage monitoring circuit 110 can be composed of multiple moving paths of input power, which are formed by switching units and clamping units. For example... Figure 3 As shown, the voltage monitoring circuit 110 of another embodiment according to the first embodiment of the present invention can be composed of a first power input unit, a second power input unit (not shown), a first switching unit 310, a second switching unit 330, a first clamping unit 320, and a second clamping unit 340. Figure 3 The detailed description of the voltage monitoring circuit will briefly describe... Figure 1 A detailed description of the voltage monitoring circuit and its corresponding description.

[0076] The first power input unit and the second power input unit receive battery power.

[0077] More specifically, the first power input unit and the second power input unit can each receive battery power 120 for voltage monitoring. By receiving battery power 120 as input from the two power input units and transmitting it to the MCU 140, even if an anomaly occurs in one transmission path, the voltage of battery power 120 is transmitted to the MCU 140 through the other transmission path, thus achieving stable voltage monitoring. A first switching unit 310 is connected to the first power input unit, and a second switching unit 330 is connected to the second power input unit.

[0078] The first clamping unit 320 clamps the voltage of the input power input through the first power input unit and the first switching unit 310 to a reference voltage, and the second clamping unit 340 clamps the voltage of the input power input through the second power input unit and the second switching unit 330 to a reference voltage. The first clamping unit 320 and the second clamping unit 340 respectively clamp the input voltage of the input power to the reference voltage. The reference voltage of the first clamping unit 320 and the reference voltage of the second clamping unit 340 can have the same voltage value. Alternatively, the reference voltage of the first clamping unit 320 and the reference voltage of the second clamping unit 340 can have different voltage values.

[0079] The first clamping unit 320 and the second clamping unit 340 can receive a reference voltage with a predetermined voltage level from the voltage supply unit 130 via separate connection lines. The first clamping unit 320 and the second clamping unit 340 can also receive a reference voltage from a single voltage supply unit 130. When the voltage supply unit 130 includes multiple output lines, the first clamping unit 320 and the second clamping unit 340 can receive the reference voltage via separate connection lines at different output lines. If any connection line of the first clamping unit 320 connected to the voltage supply unit 130 or the second clamping unit 340 connected to the voltage supply unit 130 malfunctions, the connection lines that are not malfunctioning can still operate normally to ensure stable operation of voltage monitoring of the battery power 120. The first clamping unit 320 and the second clamping unit 340 can each receive a reference voltage from multiple voltage supply units 130 instead of a single voltage supply unit 130.

[0080] The first clamping unit 320 and the second clamping unit 340 can clamp their respective input power using a reference voltage and output the clamping voltage to the MCU 140. The MCU 140 can determine the voltage of the battery power 120 by the voltage transmitted from the first clamping unit 320 or the voltage transmitted from the second clamping unit 340.

[0081] When the reference voltage of the first clamping unit 320 is abnormal, the first switching unit 310 blocks the input power from the first power input unit. When the reference voltage of the second clamping unit 340 is abnormal, the second switching unit 330 blocks the input power from the second power input unit. When the reference voltages of the first clamping unit 320 and the second clamping unit, which are respectively connected to the first switching unit 310 and the second switching unit 330, are abnormal, the input power of the power input unit connected to the clamping unit with the abnormal reference voltage is blocked.

[0082] When operating the first switching unit 310 or the second switching unit 330, the voltage clamped by the first clamping unit 320 is compared with the voltage clamped by the second clamping unit 340 to determine whether the reference voltage of the first clamping unit 320 or the reference voltage of the second clamping unit 340 is abnormal. If the reference voltage of the first clamping unit 320 or the reference voltage of the second clamping unit 340 is abnormal, the first switching unit 310 or the second switching unit 330 connected to the clamping unit with the abnormal reference voltage can be turned off. Therefore, whether the reference voltage is abnormal can be determined by comparing the voltage clamped by the first clamping unit 320 with the voltage clamped by the second clamping unit 340. The comparison of the voltage clamped by the first clamping unit 320 with the voltage clamped by the second clamping unit 340 can be performed in the MCU 140, or it can be performed in a separate processing unit or control unit.

[0083] When the voltage monitoring circuit operates normally, the voltages clamped by the first clamping unit 320 and the second clamping unit 340 have the same voltage value. However, when the voltage clamped in the first clamping unit 320 and the voltage clamped in the second clamping unit 340 have different voltages, it can be determined that an anomaly has occurred in the voltage monitoring circuit. For example, when one of the two voltages suddenly decreases or increases, it can be determined that an anomaly has occurred in the clamping unit, the voltage supply unit, or the voltage supply unit and connecting lines that clamp the corresponding voltage. Alternatively, when both voltages become greater than the reference voltage, it can be determined that an anomaly has occurred in both paths of the voltage monitoring circuit.

[0084] When an anomaly is detected in at least one of the first clamping unit 320 and the second clamping unit 340, input power can be blocked by turning off the switch unit connected to the clamping unit 111 that has been identified as having an anomaly. When anomalies are detected in both clamping units 111, input power can be blocked by turning off all switch units.

[0085] The first switching unit 310 and the second switching unit 330 can be configured with different components. For example, the first switching unit 310 can be configured with a transistor, and the second switching unit 330 can be configured with a MOSFET; or the first switching unit 310 can be configured with a MOSFET, and the second switching unit 330 can be configured with a transistor. As described above, the use of a circuit forming two paths is intended to allow normal operation through the other circuit when an abnormality occurs in one circuit; it aims to ensure normal operation of the other switching unit when an abnormality occurs in one of the switching units. In this case, slave failure can be prevented by using different types of components. When the first switching unit 310 and the second switching unit 330 are configured with different components, the probability of failure is different; therefore, even if a failure occurs in one component, the probability of the same failure occurring in the other component can be reduced. For this purpose, the first switching unit 310 and the second switching unit 330 can be configured with different components, including transistors and MOSFETs.

[0086] Another voltage monitoring circuit in the first embodiment of the present invention may include multiple power input units, multiple switching units, and multiple clamping units. The voltage monitoring paths are formed in a complex number, each path consisting of its own power input unit, switching unit, and clamping unit. Each switching unit 112 is configured with different types of switches and can block input power from the power input unit connected to the clamping unit where the reference voltage is abnormal. In this case, each of the power input units, switching units, and clamping units may consist of three or more units.

[0087] Figure 4 This is a block diagram of a circuit used to monitor battery voltage, illustrating a two-path approach for enhanced stability. Figure 4 In the voltage monitoring circuit, the voltage monitoring path formed by the switch, voltage divider unit, low-pass filter, and clamping unit includes two paths. Battery voltage 120 is separated and transmitted through the following paths: a path applied to microcontroller 140 via switch_A 310, voltage divider unit 410, low-pass filter 420, and clamping unit 320; and a path applied to microcontroller 140 via switch_B 330, voltage divider unit 430, low-pass filter 440, and clamping unit 340. The two clamping units 320 and 340 receive a 5V reference voltage from PMIC 130 via different connection lines. PMIC 130 is connected to CAN IC 350, sensor 360, and clamping units 320 and 340.

[0088] Under normal operation of the voltage monitoring circuit, each of clamping units 320 and 340 normally receives 5V_A 450 and 5V_B 460 from PMIC 130, respectively, and each of switching units 310 and 330 is also normally turned on, so that the battery voltage 120 is normally transmitted (470, 480) to each clamping unit 320 and 340.

[0089] However, when the reference voltage becomes abnormal, the switching unit operates to prevent a fault. Figure 5 This diagram illustrates the operation of the voltage monitoring circuit when a fault occurs in the connection line of PMIC 130 used to apply the reference voltage to clamp unit 320. It is assumed that the connection line of PMIC 130 used to apply the reference voltage to clamp unit 340 is not faulty. When a fault occurs in connection line 510, which applies the reference voltage 5V_A from PMIC 130 to clamp unit 320, the battery voltage may be applied to PMIC 130 via clamp unit 111 (530) instead of microcontroller 140, potentially affecting other components connected to the corresponding connection line 510 and causing a malfunction. Therefore, when a fault occurs in connection line 510, the fault is identified, and the connected switching unit 310 is turned off to block the battery voltage input. Thus, by blocking the battery voltage input, no battery voltage is transmitted to clamp unit 320, and therefore the voltage applied from clamp unit 320 to PMIC 130 can be blocked (530). In this way, it is possible to prevent other components connected to the corresponding connection line 510 from malfunctioning.

[0090] Unlike switch _A 310 connected to clamp unit 320 (where the reference voltage is abnormal), which is turned off to block the battery voltage input, switch _B 330 connected to clamp unit 340 (where the reference voltage is not abnormal) remains normally on, ensuring that the battery voltage input is not blocked. 5V_B is normally applied from PMIC 130 to clamp unit 340 to properly clamp the battery voltage within clamp unit 340 and apply the clamp voltage to microcontroller 140. Microcontroller 140 can monitor the battery voltage using the analog signal_B received through clamp unit 340 and implement functional safety mechanisms by comparing it with analog signal_A. In this way, the detection range of the normal battery voltage can be increased to approximately 90%.

[0091] Unlike Figure 4 and Figure 5 The voltage monitoring circuit in the circuit, when supplying a reference voltage from the PMIC to each clamping unit 32, 34 via a connection line 63 without including a switching unit, such as Figure 6 As shown, it may be difficult to prevent malfunctions. Figure 6 The voltage monitoring circuit in the middle can be like Figure 7 As shown in the diagram. Figure 7 As shown, the clamping unit can be implemented as a diode.

[0092] according to Figure 6 and Figure 7 The voltage monitoring circuit applies the battery voltage 12 to the microcontroller 14 via the following paths: a path consisting of voltage divider unit 41, low-pass filter 42, and clamping unit 32; and a path consisting of voltage divider unit 43, low-pass filter 44, and clamping unit 34. Under normal operation, 5V (13) from the PMIC can be normally applied (61, 62) to each clamping unit. However, if an anomaly occurs on the PMIC side, the battery voltage is applied to the PMIC side through clamping units 32 and 33, thereby affecting (64) other components connected to the PMIC, such as CAN ICs or sensors, which may lead to malfunctions. Furthermore, since only one connection line in the PMIC receives the reference voltage, the voltage monitoring circuit does not operate at this time, resulting in low coverage of functional safety mechanisms. In this case, the detection of the normal range of the battery voltage may only be about 60%.

[0093] As mentioned above, in order to prevent malfunctions, the switches included in the voltage monitoring circuit can be composed of different components, and each component can include one of a transistor and a MOSFET. Figure 8 This is a block diagram of an embodiment in which the first switching unit 310 is configured as a transistor and the second switching unit 330 is configured as a MOSFET.

[0094] The first switching unit 310 is configured as a transistor, and can be configured as a PNP transistor. It may include multiple PNP transistors, a current-limiting resistor, and a voltage-dividing resistor. Transistor 812 can be connected to a line that transmits battery voltage 120 to the clamping unit. In this case, the emitter can be connected to battery voltage 120, the collector can be connected to the clamping unit side, and the base can be connected to the voltage supply side. Here, the voltage supply unit can be a PMIC. Current flows to the collector according to the voltage applied to the PMIC side at the base, and when the voltage on the PMIC side corresponding to the reference voltage is abnormal and no voltage is applied to the base, current does not flow to the collector, thereby blocking the battery voltage input. This prevents malfunctions in the voltage monitoring circuit or other connected components. The circuit connected to transistor 812, which performs the switching operation in the PMIC, includes two voltage divider resistors 831 and 816 for dividing the PMIC voltage; it also includes transistor 811, which applies 0V to the base of transistor 812 based on the voltage input of the divided PMIC voltage; and it may also include current-limiting resistors 814 and 815 to prevent abnormal current flow. In this way, a stable switching operation can be performed.

[0095] To prevent slave failure, unlike the first switching unit 310, the second switching unit 330 can be configured as a MOSFET. It may include a P-MOSFET, an N-MOSFET, and multiple voltage divider resistors. The PMOS 822 can be connected to the line that transmits the battery voltage 120 to the clamping unit. In this case, the source can be connected to the battery voltage 120, the drain can be connected to the clamping unit side, and the gate can be connected to the PMIC side. A channel is formed between the source and drain based on the voltage applied to the gate on the PMIC side. When the voltage on the PMIC side corresponding to the reference voltage is abnormal and no voltage is applied to the base, the battery voltage input is blocked because no channel is formed between the source and drain. This prevents failure of the voltage monitoring circuitry or other connected components.

[0096] As described above, the operating voltage monitoring circuit can be used within the LCU to utilize... Figure 9The battery power 910 is used to drive the motor. Battery power 910 is applied to the dual motors 930 using two LCUs 920 and 970. Each LCU sends and receives battery power 910, CAN communication 940, and torque sensor power 950 via connector 911. Battery power 910 is applied to power supply unit 914, signal measurement unit 913, and shutdown control 918 via EMI filter 912. The power applied to shutdown control 918 is applied to the dual motors 930 as motor drive power 1 via three-phase inverter 919 and phase switch 921. Battery power applied to signal measurement unit 913 is applied to microcontroller 915 via voltage monitoring circuit 960. Voltage monitoring circuit 960 includes switching unit 961 and clamping unit 962, and can be implemented as follows: Figure 4 The circuit shown. Battery power applied to the power supply unit is applied as a clamping reference voltage to the signal measurement device 913, and as transceiver power to the vehicle CAN interface 916 and torque sensor interface 915, for transmission to CAN communication 940 and torque sensor power 950 via connector 911. The LCU 970 has the same configuration as the LCU 920 and can communicate with each other via the internal CAN interface 922. A voltage monitoring circuit 960 can be included in the signal measurement device of the LCU 970 to correspond with this.

[0097] Figure 10 It shows in Figure 6 and Figure 7 The waveforms of voltage and current measured in the voltage monitoring circuit; Figure 10 (A) is the ADC signal of the battery voltage. Figure 10 (B) is the current flowing from the clamping unit to the PMIC. Figure 10 (C) is the clamping reference voltage supplied from the PMIC.

[0098] When a stable clamping reference voltage of 5V is applied (e.g.) Figure 10 As shown in (C), it can be seen that when battery power is applied, the battery operates normally (as shown in [C]). Figure 10 (As shown in (A)). However, when the clamping reference voltage malfunctions and drops to 0V, the analog potential used to measure the battery voltage is high, and current flows from the clamping circuit to the PMIC power (e.g., Figure 10 (As shown in (B)). When this battery voltage is applied to the PMIC side, the ADC signal of the battery voltage can be observed to decrease (as shown in (B)). Figure 10 (As shown in (A)). In segment 1001 on the horizontal axis (i.e., the time axis), after the input battery power, normal ADC supply is possible, but when the clamping circuit malfunctions, the battery voltage ADC becomes abnormal (e.g., Figure 10(As shown in paragraph 1002 of (A)), and when the power of the PMIC is turned off (as shown in paragraph 1002 of (A)). Figure 10 (As shown in (B)), power is supplied to other components through clamping diodes, which may lead to malfunction.

[0099] Figure 11 It shows in Figure 4 and Figure 5 The voltage and current waveforms measured in the voltage monitoring circuit, which includes two switches, A and B. Figure 11 (A) to Figure 11 (C) is the waveform on the A side of the switch, which indicates the battery voltage ADC signal, the current flowing from the clamping unit to the PMIC, and the clamping reference voltage supplied from the PMIC. Figure 11 (D) to Figure 11 (F) shows the waveform on the B side, indicating the battery voltage ADC signal, the current flowing from the clamping unit to the PMIC, and the clamping reference voltage supplied by the PMIC. It can be seen that in segment 1101 on the horizontal axis (i.e., the time axis), normal ADC supply is possible after the battery power is input; according to the operation of switches A and B in segment 1102 (where the clamping circuit malfunctions), the battery power ADC becomes 0V (e.g., ...). Figure 11 (A) and Figure 11 (as shown in (C)), and the current flowing from the clamping circuit to the PMIC also becomes 0A (as shown in (C)). Figure 11 (B) and Figure 11 (E) is shown.

[0100] As mentioned above, reference has been made Figures 1 to 11 A voltage monitoring circuit according to a first embodiment of the present invention is described. In the following, reference will be made to... Figures 12 to 19 This invention describes an overcurrent protection circuit and an overcurrent protection method according to a second embodiment of the present invention. The detailed description of the overcurrent protection circuit and overcurrent protection method according to the second embodiment of the present invention is based on the voltage monitoring circuit, names, terminology, and functions according to the first embodiment of the present invention, and the detailed descriptions of the various embodiments may be the same as or different from each other.

[0101] In the following description, the configuration of the overcurrent protection circuit and the overcurrent protection method according to a second embodiment of the present invention will be described with reference to the accompanying drawings.

[0102] Figure 12 This is a block diagram of an overcurrent protection circuit according to an embodiment of the second embodiment of the present invention.

[0103] The overcurrent protection circuit 1000 of the second embodiment of the present invention is configured as a current detection unit 1110, a voltage detection unit 1120 and a control unit 1130, and may also include a switch 1140 or a charge pump 1150.

[0104] The current detection unit 1110 detects the current input from the power source 1210.

[0105] More specifically, the current detection unit 1110 detects the current input from the power source 1210 in order to monitor the current input from the power source 1210. The current detection unit 1110 is positioned in the input line of the power source 1210 to detect the current before the input power is applied to the load 1220.

[0106] The current detection unit 1110 may include a current mirror circuit or a shunt resistor. A current mirror circuit is a circuit that, like a mirror, replicates the current flowing in one circuit and supplies the same current to another circuit. A current mirror circuit can be as follows: Figure 14 The implementation is shown below. The current mirror circuit will be described in detail below.

[0107] A shunt resistor is a type of resistor used for measuring current and has a very low resistance value. A shunt resistor is also called a current shunt. A shunt resistor is connected in series at the location where the current is to be measured. The voltage generated in the shunt resistor is measured, and the current is measured using the equation "current = voltage / resistance".

[0108] In addition, various circuits or devices for sensing current can be used as the current detection unit 1110.

[0109] In the current detection unit 1110, the amplitude of the detected current can be proportional to the amplitude of the voltage output based on the sensed current. The current detection unit 1110 measures the current and can output a voltage as a result, and the amplitude of the detected current can be proportional to the amplitude of the voltage output based on the detected current. For example, if the current detection unit 1110 is configured to output 1V when a 10A current flows, it can output 10V when a 100A current flows. As described above, the current can be measured using the voltage output from the current detection unit 1110 by utilizing the proportional relationship between the amplitude of the current detected by the current detection unit 1110 and the amplitude of the output voltage.

[0110] The voltage detection unit 1120 detects the first voltage output from the current detection unit 1110, and outputs the first voltage to the control unit when the first voltage is less than the second voltage, and outputs the second voltage to the control unit when the first voltage is equal to or greater than the second voltage.

[0111] More specifically, the voltage detection unit 1120 can detect a first voltage output from the current detection unit 1110, but can output different voltages to the control unit depending on the amplitude of the first voltage. As described above, the current detection unit 1110 measures the current and outputs a voltage. The output voltage is applied to the control unit 1130 to measure the current based on the applied voltage from the control unit 1130. Assuming the voltage output from the current detection unit 1110 is the first voltage, when the first voltage is directly applied to the control unit 1130, and when the amplitude of the first voltage exceeds the voltage amplitude that the control unit 1130 can withstand due to overcurrent, the control unit 1130 may be damaged. Therefore, in order to protect the control unit 1130, the voltage detection unit 1120 does not directly apply the first voltage to the control unit 1130, but limits the voltage applied to the control unit 1130 based on the level of the first voltage.

[0112] When the first voltage is less than the second voltage, the voltage detection unit 1120 outputs the first voltage to the control unit 1130, and when the first voltage is equal to or greater than the second voltage, it outputs the second voltage to the control unit 1130. That is, when the first voltage is less than the second voltage set according to a voltage that may damage the control unit 1130, since the first voltage has a level that will not damage the control unit 1130, the voltage detection unit 1120 outputs the first voltage to the control unit 1130.

[0113] However, when the first voltage is equal to or greater than the second voltage, applying the first voltage under these conditions to the control unit 1130 may damage the control unit 1130. Instead of the first voltage, the second voltage, which will not damage the control unit 1130, will be output to the control unit 1130. That is, the voltage detection unit 1120 conditionally clamps the first voltage to the second voltage.

[0114] For example, when the second voltage is 5V, if the first voltage is 2V (which is less than 5V), then the first voltage of 2V is output to the control unit 1130. However, when the first voltage is 6V or greater (where the second voltage is 5V), then 5V (i.e., the second voltage) is output to the control unit 1130 instead of 6V (i.e., the first voltage).

[0115] The second voltage can be the limiting voltage of control unit 1130, or a voltage with a margin value smaller than the limiting voltage. The limiting voltage of the input / output terminals of control unit 1130 can be used. For example, when the limiting voltage of control unit 1130 is 6V, the second voltage can be set to 5V by applying a 1V margin. Applying a wider margin can further improve safety, but the allowable current range may be reduced, so the second voltage must be set appropriately. The second voltage can be set by the user.

[0116] The voltage detection unit 1120 can be implemented as a voltage detector IC. A voltage detector IC is an IC that limits the amplitude of the sensed voltage to a predetermined amplitude or a smaller amplitude, and it can be used in this way to limit the amplitude of the voltage output to the control unit 1130.

[0117] The control unit 1130 determines whether an overcurrent has been input based on the magnitude of the voltage input from the voltage detection unit 1120.

[0118] More specifically, the control unit 1130 uses the voltage input from the voltage detection unit 1120 to measure the amplitude of the current detected by the current detection unit 1110, and determines whether an overcurrent has been input based on the measured current amplitude.

[0119] As described above, the current detection unit 1110 detects current and outputs voltage, and the amplitude of the current is proportional to the amplitude of the voltage. The control unit 1130 can measure the amplitude of the current based on the amplitude of the voltage input from the voltage detection unit 1120. When the current detection unit 1110 is a current mirror circuit, the current can be measured from the voltage using the relationship between current and voltage, based on the characteristics of the current mirror circuit. When the current detection unit 1110 is a shunt resistor, the current can be measured from the voltage and the shunt resistor based on the relationship between voltage and resistance. Alternatively, the current can be measured from the voltage using a pre-stored relationship between voltage and current. In this case, the relationship between voltage and current can be stored as a lookup table or stored in memory. The overcurrent protection circuit 1000 may also include a storage unit (not shown) for storing information about the relationship between voltage and current.

[0120] When the second voltage is input, the control unit 1130 can determine that an overcurrent has occurred and can block the power input from the power source 1210. As described above, when the first voltage is equal to or greater than the second voltage, the voltage detection unit 1120 outputs the second voltage to the control unit 1130 instead of the first voltage. When the voltage applied from the voltage detection unit 1120 is the second voltage, the control unit 1130 can determine that the first voltage is equal to or greater than the second voltage, and therefore can determine that an overcurrent has occurred. However, when a voltage less than the second voltage is input, i.e., when the first voltage is input, it can be determined that no overcurrent has occurred.

[0121] When a second voltage is input, if the control unit 1130 determines that an overcurrent has occurred, it can block the power input from the power source 1210 to protect other components. When an overcurrent occurs, other components connected to the power source 1210, as well as the control unit 1130, may be damaged. To protect internal circuitry or components, the control unit 1130 can block the power input from the power source 1210. At this time, an overcurrent alarm can be generated, or the status of whether an overcurrent has occurred or whether the power source has been blocked can be transmitted to a higher-level control unit.

[0122] Switch 1140 blocks power input from power source 1210. Switch 1140 is formed at the front end of the input power source 1210, and when switch 1140 is turned off, it blocks power input from power source 1210. Switch 1140 can be configured as a FET. Alternatively, various switching devices can be used to implement switch 1140.

[0123] When an overcurrent is detected, the control unit 1130 can turn off the switch 1140 to block the power input from the power source. The control unit 1130 performs control based on the determination of an overcurrent and turns the switch 1140 on / off accordingly. When the control unit 1130 determines that the voltage detected by the voltage detection unit 1120 has generated an overcurrent, it can block the power input from the power source 1210 by turning off the switch 1140.

[0124] The charge pump 1150 converts the voltage of the control signal to the switch 1140 of the control unit 1130. A charge pump is a device that boosts or bucks an input voltage and outputs it; it is a DC-DC converter that uses a capacitor. By using capacitors to store energy, charge pumps can be manufactured in a small size and have high efficiency. Using the charge pump 1150, the voltage of the control signal from the control unit 1130 can be converted into a voltage suitable for controlling the switch 1140.

[0125] The overcurrent protection circuit according to the second embodiment of the present invention can be as follows: Figure 14 As shown in the diagram. Figure 14 An example of using a current mirror circuit as the current detection unit 1110 is shown, and the current mirror circuit can be as follows: Figure 14 The implementation is shown. Current is input from power source 1210 and flows through R2 to R3. Using a mirror circuit structure configured with four BJTs, the same current flows through R1 and R4, and a voltage across R4 is output. The voltage applied to R4 is output to voltage detection unit 1120, which can be implemented using a voltage detector. When the first voltage output from current detection unit 1110 is less than the second voltage, voltage detection unit 1120 outputs the first voltage to the MCU, which acts as control unit 1130. When the first voltage is equal to or greater than the second voltage, it outputs the second voltage to control unit 1130 to protect control unit 1130. Control unit 1130 measures the current by using the amplitude of the input voltage, and control unit 1130 is protected when the output of voltage detection unit 1120 is limited to the second voltage. When the second voltage is input, the control unit 1130 determines that an overcurrent has occurred and, in order to block the overcurrent, controls the switch 1140, which blocks the power input from the power source, to turn off. At this time, the control signal output from the control unit 1130 is converted by the charge pump 1150 for switch control and output to the switch 1140 to turn it off. Here, the switch 1140 can be a B-to-B switch. In this way, internal circuits or components, such as the bridge circuit that applies current from the power source to drive the motor, can be protected.

[0126] Figure 15 This is a comparative example of an overcurrent protection circuit according to the second embodiment of the present invention. The voltage output from the current detection unit 2011 is directly output to the MCU, which serves as the control unit 2013, potentially damaging the control unit 2013 in the event of an overcurrent. For example, if the output is set to 1V when a 10A current flows, and 10V when a 100A current flows, damage may occur when the MCU's I / O terminal voltage is 6V or higher. Therefore, it is difficult to protect the MCU in the event of an overcurrent. Furthermore, even if an overcurrent occurs, it is difficult to protect it from the effects of the overcurrent because no switch capable of blocking the overcurrent is formed.

[0127] Figure 16 and Figure 17An embodiment is shown in which an overcurrent protection circuit according to a second embodiment of the present invention is implemented inside a vehicle. The current detection unit 1110 is a current mirror circuit that detects the current input from the battery power source 1210. The voltage detection unit 1120 detects the voltage and outputs a voltage limited to a second voltage to the control unit 1130, i.e., the MCU. The control unit 1130 determines whether an overcurrent has occurred based on the input voltage. When an overcurrent occurs, it shuts off the switch 1140 by using a control signal converted via a charge pump, thereby blocking the power input from the power source 1210. The input power from the power source 1210 is applied to the gate driver 1530 and the bridge circuit 1220 through an EMC filter 1510 and a DC capacitor 1520 to drive the motor. When an overcurrent is detected, the switch 1140 is shut off, blocking the overcurrent input to the gate driver 1530 and the motor drive bridge circuit 1220, thereby protecting the internal circuitry or components.

[0128] Overcurrent protection circuit 1000 can be configured at the power input stage of the battery power 1610 of the vehicle's motor drive ECU, such as... Figure 17 As shown. Battery power 1610 is input and supplied to internal circuits and components, such as a power IC for driving a motor, a gate driver IC, and a B6 bridge circuit 1620; the overcurrent protection circuit can protect the internal circuits or components by measuring the current at the input terminal of the battery power and quickly blocking the power input from the power source when an overcurrent occurs.

[0129] Figure 18 This is a flowchart of an overcurrent protection method according to an embodiment of the second embodiment of the present invention; Figure 19 This is a flowchart of an overcurrent protection method according to another embodiment of the second embodiment of the present invention. Figure 18 and Figure 19 Detailed description of each step and Figures 12 to 17 The detailed description of the overcurrent protection circuit in the document corresponds to that in the document, so repeated descriptions will be omitted.

[0130] In step S11, a first voltage output from a current detection unit is detected. This current detection unit is used to detect the current applied from the power source. The current detection unit can be a current mirror circuit or a shunt resistor. Subsequently, in step S12, the first voltage and a second voltage are compared. As a result of the comparison in step S12, if the first voltage is less than the second voltage, the first voltage is input to the control unit in step S13. As a result of the comparison in step S12, if the first voltage is equal to or greater than the second voltage, the second voltage is input to the control unit in step S14, and in step S15, when the second voltage is input, it is determined that an overcurrent has been generated or input.

[0131] In step S15, when it is determined that an overcurrent has occurred, in step S21, the power input from the power source can be blocked.

[0132] Modified embodiments of this embodiment may include some configurations of the first embodiment and some configurations of the second embodiment. In other words, a modified embodiment may include the first embodiment, but may omit some configurations of the first embodiment, and may include some configurations of the corresponding second embodiment. Alternatively, a modified embodiment may include the second embodiment, but may omit some components of the second embodiment, and may include some components of the corresponding first embodiment.

[0133] The features, structures, effects, etc., described in the above embodiments are included in at least one embodiment, but are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, etc., shown in each embodiment can be combined or modified by those skilled in the art for other embodiments. Therefore, content related to such combinations and variations should be interpreted as being included within the scope of the embodiments.

[0134] Furthermore, embodiments of the present invention can be implemented as computer-readable code on a computer-readable recording medium. A computer-readable recording medium includes all types of recording devices storing data that can be read by a computer system.

[0135] Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, and optical data storage devices. Furthermore, they are distributed in a networked computer system where computer-readable code can be stored and executed. Moreover, the functional programs, code, and code segments used to implement this invention can be readily deduced by a programmer skilled in the art. As described above, specific aspects such as particular components, as well as limited embodiments and drawings, have been described in this invention. However, these are provided only to aid in a more general understanding of the invention, and the invention is not limited to the above embodiments. Various modifications and variations can be made by those skilled in the art based on these descriptions.

[0136] Therefore, the spirit of the present invention should not be limited to the described embodiments, and not only to the claims which will be described later, but all those contents equivalent to the claims or equivalent modifications to the claims shall be considered to fall within the scope of the spirit of the present invention.

Claims

1. A voltage monitoring circuit, comprising: The first power input unit and the second power input unit are configured to receive battery power; A first switching unit and a second switching unit, wherein the first switching unit is connected to the first power input unit and the second switching unit is connected to the second power input unit; as well as A first clamping unit and a second clamping unit, wherein the first clamping unit is configured to clamp the voltage of the input power input through the first power input unit and the first switching unit to a reference voltage, and the second clamping unit is configured to clamp the voltage of the input power input through the second power input unit and the second switching unit to a reference voltage. The first switching unit includes a transistor, and the second switching unit includes a MOSFET; Specifically, by comparing the voltage clamped in the first clamping unit with the voltage clamped in the second clamping unit, it is determined whether the reference voltage of the first clamping unit or the reference voltage of the second clamping unit is abnormal. Specifically, when the reference voltage of the first clamping unit becomes abnormal, the first switching unit blocks the application of input power from the first power input unit to the first clamping unit, and When the reference voltage of the second clamping unit is abnormal, the second switching unit blocks the input power from the second power input unit from being applied to the second clamping unit.

2. The voltage monitoring circuit according to claim 1, wherein, The first clamping unit and the second clamping unit receive a reference voltage with a predetermined voltage level from the voltage supply unit through separate connection lines.

3. The voltage monitoring circuit according to claim 1, wherein, The first clamping unit and the second clamping unit output the clamping voltage to the MCU.

4. The voltage monitoring circuit according to claim 1, wherein, The reference voltage of the first clamping unit is different from the reference voltage of the second clamping unit.

5. The voltage monitoring circuit according to claim 1 further includes: The controller receives clamping voltage from the first clamping unit and monitors the voltage of the battery power.

6. The voltage monitoring circuit according to claim 5, wherein, The controller determines whether the battery power voltage is abnormal by comparing the clamping voltage in the first clamping unit with the clamping voltage in the second clamping unit.

Images