Electronic control unit

Abstract

To provide an electronic control device capable of detecting a short circuit between inductors that constitute a multiphase power supply. [Solution] The electronic control device includes a multiphase power supply having multiple inductors, a detection unit that detects short circuits between inductors based on the output voltage of the multiphase power supply, and a processor 30 that operates by receiving the output voltage. The detection unit 40 has a comparator 42 that compares a ripple component of the output voltage with a threshold 45, an integrator 43 that counts the comparison result of the comparator 42, and a comparator 44 that compares the output of the integrator 43 with a threshold 46. The detection unit 40 outputs a predetermined signal when the output of the integrator 43 exceeds the threshold 46.

Description

[Technical Field]

[0001] The disclosure herein relates to electronic control devices. [Background technology]

[0002] Patent Document 1 discloses an electronic device. The contents of the prior art document are incorporated by reference as explanations of the technical elements in this specification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-103401 Summary of the Invention [Problem to be solved by the invention]

[0004] The electronic device disclosed in Patent Document 1 detects ripple voltage and determines whether the ripple voltage is greater than a threshold value. However, when applied to a configuration including a multiphase power supply having multiple inductors and a load that operates by receiving the output voltage of the multiphase power supply, it is not possible to distinguish whether the large ripple voltage is due to a short circuit between the inductors or due to fluctuations in the load. Further improvements are required in electronic control devices in the above respects and in other respects not mentioned.

[0005] One object of the present disclosure is to provide an electronic control device that can detect a short circuit between inductors that make up a multiphase power supply. [Means for solving the problem]

[0006] An electronic control device according to one aspect of the disclosure includes: a multiphase power supply (22) having a plurality of inductors (24); a detection unit (40) that detects a short circuit between inductors based on an output voltage of the multiphase power supply; a load (30) that operates upon receiving the output voltage; Equipped with The detection unit is a first comparator (42) that compares the ripple component of the output voltage with a predetermined first threshold; an integrator (43) that counts the comparison result of the first comparator; a second comparator (44) that compares the output of the integrator with a second predetermined threshold; When the output of the integrator exceeds a second threshold, a predetermined signal is output.

[0007] The disclosed electronic control device can detect a steady (continuous) increase in the ripple component of the output voltage, thereby detecting a short circuit between inductors that make up the multiphase power supply.

[0008] The various aspects disclosed in this specification employ different technical means to achieve their respective objectives. The reference numerals in parentheses in the claims are intended to exemplarily indicate the corresponding parts of the embodiments described below, and are not intended to limit the technical scope. The objectives, features, and advantages disclosed in this specification will become more apparent by reference to the following detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an electronic control device according to a first embodiment. [Figure 2] FIG. 1 is a circuit diagram showing a multiphase power supply. [Figure 3] FIG. 1 is a perspective view showing a coupled inductor. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] FIG. 10 is a diagram illustrating an example of a short circuit between inductors. [Figure 7] 10A and 10B are diagrams showing PWM waveforms of each phase and a Vout1 waveform. [Figure 8] FIG. 2 is a block diagram showing a detection unit. [Figure 9] 4 is a timing chart showing various signal waveforms. [Figure 10] 10 is a flowchart showing a process executed by a detection unit. [Figure 11] FIG. 10 is a block diagram showing a detection unit in an electronic control device according to a second embodiment. [Figure 12] 10 is a flowchart showing a process executed by a detection unit. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, several embodiments will be described with reference to the drawings. Note that in each embodiment, corresponding components are designated by the same reference numerals, and redundant description may be omitted. When only a portion of the configuration is described in each embodiment, the configuration of another embodiment previously described may be applied to the remaining portion of the configuration. Furthermore, in addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of several embodiments may be partially combined together even if not explicitly stated, provided that there is no particular problem with the combination.

[0011] (First embodiment) The electronic control device according to this embodiment can be applied to, for example, a mobile body. Mobile bodies include vehicles such as engine-driven vehicles, hybrid vehicles, and motor-driven vehicles, as well as flying objects such as drones and eVTOLs, ships, construction machinery, and agricultural machinery. eVTOL is an abbreviation for electronic Vertical Take-Off and Landing aircraft. For example, when applied to a vehicle, the electronic control device controls equipment mounted on the vehicle. The electronic control device is sometimes referred to as an ECU. ECU is an abbreviation for Electronic Control Unit.

[0012] The electronic control unit may, for example, execute control related to the movement of a mobile object, or may execute control unrelated to movement. The electronic control unit may, for example, be an autonomous driving ECU, or an ADAS ECU that executes control to assist the driver in driving operations. ADAS is an abbreviation for Advanced Driving Assistant System. For example, levels 3 to 5 defined by the Society of Automotive Engineers International (SAE International) correspond to autonomous driving levels, and levels 1 and 2 correspond to driving assistance levels. The electronic control unit may be an infotainment ECU or a cockpit ECU. The cockpit ECU controls meter devices, navigation devices, air conditioning devices, etc.

[0013] <Electronic control device> FIG. 1 shows an example of an electronic control device according to this embodiment. The electronic control unit (ECU) 10 includes a power supply circuit 20, a processor 30, and a detection unit 40. The power supply circuit 20 has at least a multiphase power supply. The illustrated electronic control unit 10 is mounted on a vehicle. The power supply circuit 20 includes a primary power supply circuit 21 and a secondary power supply circuit 22. The secondary power supply circuit 22 is a multiphase power supply. Hereinafter, the secondary power supply circuit 22 may be referred to as the multiphase power supply 22. The multiphase power supply 22 has a plurality of inductors 24, as will be described later.

[0014] The primary power supply circuit 21 and the secondary power supply circuit 22 are configured to be able to step down an input voltage to a predetermined voltage and output it. The primary power supply circuit 21 and the secondary power supply circuit 22 are step-down DC-DC converters. For example, the primary power supply circuit 21 generates a constant voltage (e.g., 5 V) lower than the power supply voltage based on the power supplied from a battery mounted on the vehicle. The secondary power supply circuit 22 generates a constant voltage (e.g., around 1 V) lower than the voltage generated by the primary power supply circuit 21 based on the output of the primary power supply circuit 21.

[0015] The processor 30 is an example of a load that operates by receiving power from the power supply circuit 20 (secondary power supply circuit 22). The processor 30 is, for example, a CPU, a GPU, or the like. CPU is an abbreviation for Central Processing Unit. GPU is an abbreviation for Graphics Processing Unit. The electronic control device 10 may include only one processor 30 or multiple processors 30. The electronic control device 10 may include multiple types of processors 30. The processor 30 executes a control program stored in a memory (not shown) to perform predetermined processing for control. The memory is a non-transitory tangible storage medium that non-temporarily stores computer-readable programs, data, etc.

[0016] The core voltage of the processor 30 is around 1 V (for example, less than 1 V), and the load current is several tens of amperes or more (for example, 100 A or more). To accommodate such low voltages and large currents, the electronic control device 10 employs a multiphase power supply 22 as the power supply circuit 20. The multiphase power supply 22 steps down the input voltage to a voltage corresponding to the core voltage of the processor 30 and outputs the voltage. Use of the multiphase power supply 22 makes it possible to accommodate the increased performance of the processor 30 associated with improved autonomous driving levels and advances in infotainment functions, particularly autonomous driving level 3 and above.

[0017] The detection unit 40 detects a short circuit that occurs between inductors that make up the multiphase power supply 22. The detection unit 40 detects a short circuit that occurs between different inductors 24 based on the output voltage Vout of the multiphase power supply 22. Details of the detection unit 40 will be described later.

[0018] <Multiphase power supply> FIG. 2 is a circuit diagram showing a multiphase power supply (secondary power supply circuit). For convenience, FIG. 2 shows a simplified view of some of the drivers. The multiphase power supply 22 includes a plurality of drivers 23, a plurality of inductors 24 provided corresponding to the drivers 23, and a capacitor 25. The multiphase power supply 22 has a plurality of phases. The phases may also be referred to as stages, channels, etc.

[0019] The driver 23 includes switching elements 23H and 23L, respectively. The switching elements 23H and 23L may be, for example, MOSFETs or IGBTs. The switching elements 23H and 23L may be bipolar transistors. MOSFET is an abbreviation for Metal Oxide Semiconductor Field Effect Transistor. IGBT is an abbreviation for Insulated Gate Bipolar Transistor. The switching elements 23H and 23L are connected in series between a power supply line to which an input voltage Vin is input and a ground (GND) line, with the switching element 23H on the high side. The input voltage Vin is the output of the primary power supply circuit 21.

[0020] One end of the inductor 24 is connected to the connection point (midpoint) of the switching elements 23H and 23L. The other end of the inductor 24 is connected to the output line. The inductor 24 is provided individually for the driver 23. The drivers 23 and inductors 24 of each phase are connected in parallel with each other. Parallelization makes it possible to increase the output current, i.e., the load current, from the multiphase power supply 22. The number of phases is not particularly limited. The illustrated multiphase power supply 22 has three phases.

[0021] The capacitor 25 is connected to the output line. The positive terminal of the capacitor 25 is connected to the output line. The negative terminal of the capacitor 25 is connected to ground. The capacitor 25 may be provided individually for each phase, or may be provided commonly to multiple phases. In the illustrated multiphase power supply 22, a capacitor 25 is provided for each phase.

[0022] The electronic control device 10 may include a power supply control unit (not shown). The multi-phase power supply 22 may include a power supply control unit. The power supply control unit performs voltage mode control, for example, by feedback of the output voltage Vout, and controls the operation of the driver 23, i.e., the operation of the switching elements 23H and 23L. The power supply control unit determines the pulse width (duty ratio) of the PWM signal based on the output voltage Vout, and controls the output voltage Vout of the multi-phase power supply 22. The power supply control unit may perform current mode control instead of voltage mode control.

[0023] The power supply control unit synchronizes the multiple drivers 23 so that they perform switching operations at different phases. Using multiple phases in this way can artificially increase the switching frequency even when the switching frequencies of the multiple drivers 23 are the same. This reduces the ripple component of the output voltage and improves responsiveness. The power supply control unit switches the drivers 23 to perform switching operations, i.e., the number of drive phases, depending on the load current. The power supply control unit compares the load current with a threshold current and increases and / or decreases the number of drive phases depending on the comparison result.

[0024] The multiphase power supply 22 may be configured with a plurality of individually provided inductors 24. The multiphase power supply 22 may be configured with an inductor component in which a plurality of inductors 24 are packaged. An exemplary multiphase power supply 22 is configured with a coupled inductor 24C. FIG. 3 is a perspective view showing an example of a coupled inductor. FIG. 4 is a perspective view showing a core. FIG. 5 is a perspective view showing a coil.

[0025] In the following, the direction in which multiple coils are arranged is referred to as the X direction. The direction perpendicular to the X direction, in which the two end cores are arranged, is referred to as the Y direction. The direction perpendicular to both the X and Y directions is referred to as the Z direction. Unless otherwise specified, the shape viewed from the Z direction, in other words, the shape along the XY plane defined by the X and Y directions, is referred to as the planar shape. The planar view from the Z direction may sometimes be simply referred to as the planar view.

[0026] One coupled inductor 24C provides the multiple inductors 24 that make up the multiphase power supply 22. As shown in FIGS. 3 to 5, the coupled inductor 24C includes a core 26 and multiple coils 27. The coils 27 are arranged on one core 26, i.e., the common core 26, and are magnetically coupled to each other. By using the coupled inductor 24C, magnetic fluxes between phases can be canceled out, reducing the effective inductance.

[0027] The core 26 is formed using a magnetic material such as ferrite. The core 26 functions as a magnetic circuit. The core 26 has a plurality of core cores 261 and end cores 262, 263. The core 26 may be formed of a single member or a combination of a plurality of members. The coil 27 is inserted through the core 26. The core core 261 is provided individually for each coil 27. The coil 27 is wound around the core core 261. The core core 261 extends in the Y direction. The plurality of core cores 261 are lined up in the X direction at predetermined intervals. The illustrated core 26 has three core cores 261. Each core core 261 is substantially rectangular parallelepiped-shaped. The three core cores 261 have the same shape.

[0028] The end cores 262, 263 are arranged opposite to each other in the Y direction. The end cores 262, 263 sandwich the core core 261 between them. The end cores 262, 263 extend in the X direction, which is the arrangement direction of the multiple core cores 261. One ends of the multiple core cores 261 are connected to the end core 262, and the other ends of the multiple core cores 261 are connected to the end core 263. The end cores 262, 263 magnetically connect the multiple core cores 261. The illustrated end cores 262, 263 have the same shape. The end cores 262, 263 are substantially rectangular parallelepipeds with the X direction as their longitudinal direction.

[0029] The coil 27 is formed using a metal material with good conductivity, such as copper. The coil 27 is formed by processing a metal plate material, rather than a metal wire material. The metal plate material is sometimes called a metal frame. The multiple coils 27 are formed using the same material and have the same shape. The multiple coils 27 have approximately the same inductance. The multiple coils 27 are lined up in the X direction at a predetermined interval. The multiple coils 27 are lined up in the same direction. The coils 27 are fixed to the core 26, for example, by adhesive. By bringing adjacent coils 27 closer to each other, the magnetic flux cancellation effect can be improved. In other words, the effective inductance reduction effect can be improved.

[0030] The coil 27 is formed by bending a metal plate having a predetermined thickness. The coil 27 (coupled inductor 24C) is mounted on a substrate (not shown). The coil 27 has terminal portions 271 and 272, side wall portions 273 and 274, and an upper wall portion 275. The terminal portions 271 and 272 are external connection terminals of the coil 27. The plate thickness direction of the terminal portions 271 and 272 is approximately parallel to the Z direction. The terminal portions 271 and 272 extend in the Y direction. The illustrated terminal portions 271 and 272 have a substantially rectangular planar shape with the Y direction as their longitudinal direction. The terminal portions 271 and 272 are aligned in the X direction at a predetermined interval. A portion of the side surface of the terminal portion 271 faces a portion of the side surface of the terminal portion 272 in the X direction.

[0031] The side wall portion 273 is continuous with a portion of the terminal portion 271 that faces the terminal portion 272. The side wall portion 273 is bent so as to form an angle of approximately 90 degrees with respect to the terminal portion 271. The thickness direction of the side wall portion 273 is approximately parallel to the X direction. The side wall portion 273 has a width equal to the length of the facing portions of the terminal portions 271, 272, and extends in the Z direction. Similarly, the side wall portion 274 is continuous with a portion of the terminal portion 272 that faces the terminal portion 271. The side wall portion 274 is bent so as to form an angle of approximately 90 degrees with respect to the terminal portion 272. The thickness direction of the side wall portion 274 is approximately parallel to the X direction. The side wall portion 274 has a width equal to the length of the facing portions of the terminal portions 271, 272, and extends in the Z direction, the same direction as the side wall portion 273. The lower ends of the side walls 273 and 274 are continuous with the terminal portions 271 and 272 .

[0032] The upper wall portion 275 bridges the side wall portions 273, 274. The upper wall portion 275 extends in the X direction. One end of the upper wall portion 275 is continuous with the upper end of the side wall portion 273, and the other end is continuous with the upper end of the side wall portion 274. The upper wall portion 275 has the same width as the side wall portions 273, 274.

[0033] The opposing portions of the terminal portions 271, 272, the side walls 273, 274, and the upper wall portion 275 surround the core 261. The opposing portions of the terminal portions 271, 272, the side walls 273, 274, and the upper wall portion 275 are attached to and wound around the core 261. End cores 262, 263 are arranged in the portions excluding the opposing portions of the terminal portions 271, 272, i.e., in the extended portions.

[0034] <Inductor short circuit and ripple fluctuation> 6 is a diagram showing an example of an inter-inductor short circuit. In a configuration having multiple inductors 24, for example, a configuration in which multiple inductors 24 are lined up in a predetermined direction, there is a risk of a short circuit occurring between adjacent inductors due to the inclusion of conductive foreign matter, migration, etc. In particular, when using coupled inductors 24C, bringing adjacent coils 27 closer to each other as described above makes it easier for a short circuit to occur between the adjacent inductors.

[0035] 6, among the three phases, a short circuit occurs between the inductor 24 of phase 1 and the inductor 24 of phase 2. Vout1 shown in FIG.

[0036] Figure 7 shows the PWM waveforms of each phase and the Vout1 waveform. Figure 7 shows a simplified representation of the on-period at a given duty ratio. The PWM waveform indicates the on-period and off-period. Figure 7 shows the waveform when a coupled inductor is used. Of the output voltage Vout1, the dashed line shows the normal waveform, and the solid line shows the waveform when a short occurs. The solid line shows the waveform when a short occurs between the inductors of phase1 and phase2, as shown in Figure 6. The two-dot chain lines for the output voltage Vout1 indicate the overvoltage detection threshold and undervoltage detection threshold.

[0037] Under normal conditions, the output voltage Vout1 rises significantly during the on-period of phase 1. Due to the influence of magnetic coupling, the output voltage Vout1 also rises during the on-period of phase 2 and phase 3. The rises during the on-period of phase 2 and phase 3 are smaller than the rise during the on-period of phase 1.

[0038] When an inductor short occurs, the output voltage Vout1 rises significantly during the on-period of phase 1 and the on-period of phase 2. Due to the effect of magnetic coupling, the output voltage Vout1 also rises during the on-period of phase 3. The rise during the on-period of phase 3 is smaller than the rise during the on-period of phase 1 and the on-period of phase 2. An inductor short approximately doubles the ripple fluctuation, but in almost no cases does it reach the overvoltage detection threshold. In other words, an inductor short cannot be detected using the overvoltage detection threshold and undervoltage detection threshold used in general fault diagnosis.

[0039] <Detection section> Fig. 8 is a block diagram showing the detection unit, Fig. 9 is a timing chart showing various signal waveforms, and Fig. 10 is a flowchart showing the processing executed by the detection unit.

[0040] As described above, the detection unit 40 detects an inter-inductor short circuit in the multi-phase power supply 22. At least a part of the functions of the detection unit 40 may be implemented by hardware, or at least a part of the functions may be implemented by software. The detection unit 40 may include, for example, an analog circuit or a digital circuit. The detection unit 40 includes a high-pass filter (HPF) 41, a comparator (CMP1) 42, an integrator (INT) 43, and a comparator (CMP2) 44.

[0041] The high-pass filter 41 is a filter that passes signals with frequencies higher than a predetermined frequency (cutoff frequency). The high-pass filter 41 passes ripple components, which are AC components, in the output voltage Vout of the multi-phase power supply 22. The ripple components are sometimes referred to as ripple voltage.

[0042] The comparator 42 compares the ripple component with a threshold value (TH1) 45 and outputs the comparison result. The comparator 42 determines whether the ripple component is increasing. The integrator 43 counts the comparison result of the comparator 42. The integrator 43 counts when the ripple component exceeds the threshold value 45. The integrator 43 detects whether the ripple component is continuously increasing. The comparator 44 compares the output of the integrator 43 with a threshold value (TH2) 46 and outputs the comparison result. The comparator 44 determines whether an inter-inductor short circuit has occurred based on the output of the integrator 43.

[0043] The detection unit 40 outputs a predetermined signal when the output of the integrator 43 exceeds a threshold value 46. The detection unit 40 outputs a signal based on the comparison result of the comparator 44. In the illustrated detection unit 40, the comparison result of the comparator 44 is output to the processor 30. When the output of the integrator 43 exceeds the threshold value 46, the comparator 44 outputs a signal to the processor 30 to reset the processor 30. The comparator 44 activates an output signal, a Reset signal, to reset the processor 30. In other words, it enables the reset of the processor 30.

[0044] FIG. 9 is a timing chart showing an example of various signal waveforms. FIG. 9 shows the PWM waveforms of each phase, the Vout waveform, the output waveform of the high-pass filter (HPC) 41, the output waveform of the comparator (CMP1) 42, the output waveform of the integrator (INT) 43, and the output waveform of the comparator (CMP2) 44. As with FIG. 7, FIG. 9 shows a simplified ON period of a predetermined duty ratio. Also, the Vout waveform is shown in a simplified form. TH1 in FIG. 9 indicates a threshold value 45 (threshold voltage), and TH2 indicates a threshold value 46 (threshold voltage).

[0045] FIG. 9 shows waveforms when a short circuit occurs between the inductor 24 of phase 1 and the inductor 24 of phase 2 at time T1, as in FIG. 6. When a short circuit occurs between the inductors of phases 1 and 2 at time T1, current flows through the inductors 24 of phases 1 and 2 during the on-period of phase 1. Also, current flows through the inductors 24 of phases 1 and 2 during the on-period of phase 2. Therefore, fluctuations in Vout become larger after time T1.

[0046] As a result, fluctuations in the output of the high-pass filter (HPF) 41 after timing T1, i.e., fluctuations in the ripple component, also increase. Therefore, the output voltage of the high-pass filter 41 periodically exceeds the threshold value (TH1) 46 after timing T1. The output voltage of the high-pass filter 41 exceeds the threshold value (TH1) 46 during the on-periods of phases 1 and 2.

[0047] Comparator (CMP1) 42 outputs an H-level signal indicating an increase in the ripple component when the output voltage of high-pass filter 41 exceeds threshold (TH1) 46. Comparator 42 outputs an L-level signal when the output voltage of high-pass filter 41 is equal to or lower than threshold 46. Comparator 42 periodically outputs H-level signals from timing T1 onwards.

[0048] The integrator (INT) 43 counts the number of H-level signals output from the comparator 42. When the comparator 42 outputs an H-level signal, the integrator 43 adds a voltage. Between voltage additions, the voltage decreases due to discharge. After timing T1, the comparator 42 periodically outputs H-level signals, so the output of the integrator 43 increases with each count. When the comparator 42 outputs H-level signals a predetermined number of times in succession, the output of the integrator 43 exceeds the threshold value (TH2) 46.

[0049] The threshold value 46 is set to a value that is greater than the output voltage of the integrator 43 when the number of times that the comparator 42 outputs an H-level signal is less than a predetermined number, and is smaller than the output of the integrator 43 when the number of times that the comparator 42 outputs an H-level signal is equal to or greater than the predetermined number. The predetermined number is set to a number that is greater than the number of times that the ripple component exceeds the threshold value 45 under the maximum fluctuation condition of the processor 30. The maximum fluctuation condition is a fluctuation condition under which the fluctuation of the ripple component is greatest among the load fluctuations.

[0050] The comparator (CMP2) 44 outputs a Reset signal to the processor 30. When the output of the integrator 43 exceeds a threshold (TH2) 46, the comparator 44 outputs an L-level signal, which is a signal for resetting the processor 30. When the output of the integrator 43 is equal to or less than the threshold 46, the comparator 44 outputs an H-level signal. When the output of the integrator 43 exceeds the threshold 46, the comparator 44 activates the Reset signal, that is, switches it from H to L. In this way, when the output of the integrator 43 exceeds the threshold 46, the processor 30 is reset (restarted).

[0051] 10 is a flowchart showing an example of a short circuit detection process executed by the detecting section 40. For example, when power is supplied to the detecting section 40 and the detecting section 40 starts up, the detecting section 40 executes the short circuit detection process.

[0052] The detection unit 40 first resets the integrator 43 (step S10). The illustrated detection unit 40 resets the voltage of the integrator 43 to zero (0) V, which is the initial state. Next, the detection unit 40 subtracts a constant voltage (predetermined voltage) from the integrator 43 (step S20). Note that although this is a process of sequentially subtracting a constant amount, if the integrator 43 is configured with an analog integration circuit as illustrated in FIG. 9, the voltage will be decreasing due to constant discharge from a discharge resistor or the like. The integrator 43 does not take negative values, and if the voltage is 0 V, it will remain at 0 V even after the subtraction process.

[0053] Next, the detection unit 40 determines whether the output of the high-pass filter 41 exceeds a threshold value (TH1) 45 (step S30). If the output of the high-pass filter 41 exceeds the threshold value 45, the detection unit 40 adds a voltage to the integrator 43 (step S40). In other words, the integrator 43 counts. This addition causes the output voltage of the integrator 43 to increase. Because the added voltage is greater than the subtracted voltage in step S20, if the determination in step S30 is YES continuously, the output voltage of the integrator 43 continues to increase until it reaches a saturation voltage. If the output of the high-pass filter 41 is equal to or less than the threshold value 45 in step S30, the detection unit 40 skips the process of step S40 and proceeds to step S50.

[0054] Next, the detection unit 40 determines whether the output of the integrator 43 exceeds the threshold value (TH2) 46 (step S50). If the output of the integrator 43 exceeds the threshold value 46, the detection unit 40 enables a reset of the processor 30 (step 60). In the illustrated detection unit 40, the comparator 44 activates the Reset signal, that is, outputs an L-level signal, thereby resetting the processor 30. If the output of the integrator 43 is equal to or less than the threshold value 46 in step S50, the detection unit 40 again executes the processes from step S20 onwards.

[0055] After executing the process of step S60, the detection unit 40 determines whether the power of the detection unit 40 is off or not (step S70). If the power is off, the short detection process ends. If the power is not off, the detection unit 40 executes the processes from step S20 onwards again. Note that the process of step S70 may be omitted, and the short detection process may end after executing the process of step S60.

[0056] <Summary of the First Embodiment> The electronic control device 10 of this embodiment includes a multiphase power supply 22, a processor 30, and a detection unit 40. The detection unit 40 has a comparator 42, an integrator 43, and a comparator 44. The comparator 42 compares the ripple component of the output voltage Vout of the multiphase power supply 22 with a predetermined threshold 45. The integrator 43 counts the comparison result of the comparator 42. The comparator 44 compares the output of the integrator 43 with a threshold 46. The detection unit 40 outputs a predetermined signal when the output of the integrator 43 exceeds the threshold 46. In the illustrated electronic control device 10, the processor 30 corresponds to a load. The comparator 42 corresponds to a first comparator, and the comparator 44 corresponds to a second comparator. The threshold 45 corresponds to a first threshold, and the threshold 46 corresponds to a second threshold.

[0057] The provision of the detecting unit 40 having the above configuration makes it possible to detect a steady (continuous) increase in the ripple component of the output voltage Vout. Therefore, it is possible to detect a short circuit occurring between different inductors 24 in the multiphase power supply 22. For example, it is possible to detect a steady increase in the ripple component due to a short circuit between inductors, distinguishing it from a temporary increase in the ripple component caused by a load fluctuation.

[0058] As illustrated, the detection unit 40 may output a signal for resetting the load (processor 30) as the predetermined signal. Since the load operates by receiving the output voltage Vout, if a short circuit occurs between the inductors and the power supply becomes unstable, the load may operate abnormally. By resetting the load when the output of the integrator 43 exceeds the threshold value 46, it is possible to prevent the load from operating abnormally.

[0059] As illustrated, the detection unit 40 may include a high-pass filter 41 that passes the ripple component. The comparator 42 may be configured to compare the ripple component that has passed through the high-pass filter 41 with a threshold value 45. By using the high-pass filter 41, it is possible to pass only the ripple component (AC component) of the output voltage Vout. This improves the accuracy of detecting an increase in the ripple component.

[0060] As shown in the example, threshold value 46 may be set to a value that is greater than the output of integrator 43 when the number of times the ripple component exceeds threshold value 45 is less than a predetermined number, and less than the output of integrator 43 when the number of times the ripple component exceeds threshold value 45 is equal to or greater than a predetermined number. By setting the number of times to detect an increase in ripple component in this way, it is possible to accurately distinguish between an increase in ripple component due to load fluctuations and an increase in ripple component due to a short circuit between inductors.

[0061] As illustrated, the predetermined number of times may be set to a number greater than the number of times the ripple component exceeds the threshold value 45 under maximum load (processor 30) fluctuation conditions. This prevents an increase in the ripple component due to load fluctuation from being erroneously determined as an increase in the ripple component due to an inter-inductor short circuit.

[0062] As illustrated, the multiphase power supply 22 may have a coupled inductor 24C including multiple inductors 24 arranged side by side in a predetermined direction and magnetically coupled to one another. By employing a coupled inductor 24C with such a configuration, it is possible to enhance the effect of magnetic flux cancellation and reduce the effective inductance. Meanwhile, when adjacent inductors 24 approach each other, a short circuit between the inductors is more likely to occur due to foreign matter or the like. However, by providing the above-described detector 40, it is possible to detect such a short circuit between the inductors. The detector 40 is suitable for a multiphase power supply 22 having a coupled inductor 24C.

[0063] (Second embodiment) This embodiment is a modification based on the preceding embodiment, and the description of the preceding embodiment can be used in this embodiment. In addition to the preceding embodiment, the integrator may be reset at predetermined time intervals.

[0064] FIG. 11 is a block diagram illustrating an example of a detection unit in an electronic control device according to this embodiment. The detection unit 40 illustrated in FIG. 11 further includes a timer counter (TC) 47 in addition to the configuration illustrated in FIG. 8 of the preceding embodiment. The timer counter 47 starts measuring time when the output of the comparator 42 switches to an H level. The timer counter 47 starts measuring time when the comparator 42 starts outputting an H level. The timer counter 47 starts measuring time, for example, triggered by the first H level signal periodically output by the comparator 42 when an inductor short occurs. The integrator 43 resets its count when a predetermined period of measurement by the timer counter 47 has elapsed. In the illustrated integrator 43, the voltage is reset to zero (0) V. The predetermined period is indicated as a predetermined period PP in FIG. 9. The timer counter 47 is reset, for example, in synchronization with the resetting of the integrator 43.

[0065] The threshold value 46 is set to a value that is greater than the output voltage of the integrator 43 when the number of times that the comparator 42 outputs an H-level signal in a predetermined period is less than a predetermined number, and is smaller than the output of the integrator 43 when the number of times that the comparator 42 outputs an H-level signal in a predetermined period is equal to or greater than a predetermined number.

[0066] 12 is a flowchart showing an example of a short circuit detection process executed by the detection unit. The process shown in FIG. 12 is the same as the process shown in the preceding embodiment (see FIG. 10), except that step S80 is added.

[0067] If the result of the determination in step S50 is that the output of the integrator 43 exceeds the threshold value 46, the detection unit 40 executes the process of step S60. If the output of the integrator 43 is equal to or less than the threshold value 46, the detection unit 40 determines whether or not a predetermined period of time has elapsed (step S80). If the predetermined period of time has not elapsed, the detection unit 40 executes the processes from step S20 onwards again. If the predetermined period of time has elapsed, the detection unit 40 returns to step S10 and resets the integrator 43. The other configurations are the same as those described in the preceding embodiment. The process of step S70 may be omitted, and the short detection process may end once the process of step S60 has been executed.

[0068] <Summary of the second embodiment> As shown in the example, threshold value 46 may be set to a value that is greater than the output of integrator 43 when the number of times the ripple component exceeds threshold value 45 in a predetermined period is less than a predetermined number, and less than the output of integrator 43 when the number of times the ripple component exceeds threshold value 45 in a predetermined period is equal to or greater than a predetermined number. In this way, by setting the detection period in addition to the number of times an increase in ripple component is detected, it is possible to more accurately distinguish between an increase in ripple component due to load fluctuations and an increase in ripple component due to an inductor short circuit.

[0069] As illustrated, the count of integrator 43 may be reset if the number of times the ripple component exceeds threshold value 45 is less than a predetermined number at the end of a predetermined period. In other words, the count of integrator 43 may be reset if the output of integrator 43 does not exceed threshold value 46 during the predetermined period. This makes it possible to prevent an increase in the ripple component due to a load fluctuation from being erroneously determined as an increase in the ripple component due to an inter-inductor short circuit when load fluctuations occur consecutively at relatively short intervals and the output of integrator 43 increases.

[0070] (Other embodiments) The disclosure in this specification and drawings, etc. is not limited to the exemplified embodiments. The disclosure encompasses the exemplified embodiments and modifications thereto by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure encompasses the omission of parts and / or elements from the embodiments. The disclosure encompasses the substitution or combination of parts and / or elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. Some disclosed technical scopes are defined by the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the claims.

[0071] The disclosure in the specification, drawings, etc. is not limited by the claims. The disclosure in the specification, drawings, etc. encompasses the technical ideas described in the claims, and extends to more diverse and broader technical ideas than the technical ideas described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification, drawings, etc. without being bound by the claims.

[0072] When an element or layer is referred to as being "on," "coupled," "connected," or "bonded," it may be directly on, coupled, connected, or bonded to another element or layer, and intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly coupled," "directly connected," or "directly bonded" to another element or layer, no intervening elements or layers are present. Other terms used to describe relationships between elements should be construed in a similar manner (e.g., "between" vs. "directly between," "adjacent" vs. "directly adjacent," etc.). As used in this specification, the term "and / or" includes any and all combinations of one or more of the associated listed items. That is, reference to A and / or B means at least one of A and B.

[0073] Spatially relative terms such as "inside," "outside," "back," "below," "low," "top," "top," and the like are used herein to facilitate the description of one element or feature's relationship to other elements or features, as illustrated. Spatially relative terms may be intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures were turned over, elements described as "below" or "directly below" other elements or features would then be oriented "above" the other elements or features. Thus, the term "bottom" can encompass both an orientation of top and bottom. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used in this specification would be interpreted accordingly.

[0074] Although an example in which the power supply circuit 20 includes the primary power supply circuit 21 and the secondary power supply circuit 22 has been described, the present invention is not limited to this. Although an example in which the multi-phase power supply 22 forms the secondary power supply circuit has been described, the present invention is not limited to this.

[0075] (Disclosure of technical ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be written in a multiple dependent form, with the subsequent clause referring to the preceding clause as an alternative. Furthermore, some clauses may be written in a multiple dependent form, referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0076] <Technical philosophy 1> a multiphase power supply (22) having a plurality of inductors (24); a detection unit (40) that detects a short circuit between the inductors based on an output voltage of the multiphase power supply; a load (30) that operates upon receiving the output voltage; Equipped with The detection unit a first comparator (42) that compares the ripple component of the output voltage with a predetermined first threshold; an integrator (43) that counts the comparison result of the first comparator; a second comparator (44) that compares the output of the integrator with a second predetermined threshold value; an electronic control device that outputs a predetermined signal when the output of the integrator exceeds the second threshold value;

[0077] <Technical philosophy 2> The electronic control device according to Technical Idea 1, wherein the detection unit outputs a signal for resetting the load as the predetermined signal.

[0078] <Technical philosophy 3> The detection unit has a high-pass filter (41) that passes the ripple component of the output voltage, The electronic control device according to Technical Idea 1 or 2, wherein the first comparator compares the ripple component that has passed through the high-pass filter with the first threshold value.

[0079] <Technical philosophy 4> The electronic control device described in any one of Technical Ideas 1 to 3, wherein the second threshold value is set to a value that is greater than the output of the integrator when the number of times the ripple component exceeds the first threshold value is less than a predetermined number of times, and is smaller than the output of the integrator when the number of times the ripple component exceeds the first threshold value is the predetermined number of times or more.

[0080] <Technical philosophy 5> The electronic control device described in Technical Idea 4, wherein the second threshold value is set to a value that is greater than the output of the integrator when the number of times that the ripple component exceeds the first threshold value in a specified period is less than the specified number of times, and is smaller than the output of the integrator when the number of times that the ripple component exceeds the first threshold value in the specified period is equal to or greater than the specified number of times.

[0081] <Technical philosophy 6> The electronic control device according to Technical Idea 5, wherein the count of the integrator is reset if the number of times the ripple component exceeds the first threshold value at the end of the predetermined period is less than the predetermined number of times.

[0082] <Technical philosophy 7> The electronic control device according to any one of Technical Concepts 4 to 6, wherein the predetermined number of times is set to be greater than the number of times the ripple component exceeds the first threshold value under a maximum load fluctuation condition.

[0083] <Technical philosophy 8> The multiphase power supply has a coupled inductor (24C) including a plurality of the inductors, The electronic control device according to any one of Technical Concepts 1 to 7, wherein the coupled inductors are arranged side by side in a predetermined direction and are magnetically coupled to each other. [Explanation of symbols]

[0084] 10...Electronic control device, 20...Power supply circuit, 21...Primary power supply circuit, 22...Secondary power supply circuit (multi-phase power supply), 23...Driver, 23H, 23L...Switching element, 24...Inductor, 24C...Coupled inductor, 25...Capacitor, 26...Core, 261...Center core, 262, 263...End core, 27...Coil, 271, 272...Terminal portion, 273, 274...Side wall portion, 275...Upper wall portion, 30...Processor, 40...Detection portion, 41...HPF, 42...Comparator, 43...Integrator, 44...Comparator, 45...First threshold, 46...Second threshold, 47...Timer counter

Claims

1. a multiphase power supply (22) having a plurality of inductors (24); a detection unit (40) that detects a short circuit between the inductors based on an output voltage of the multiphase power supply; a load (30) that operates upon receiving the output voltage; Equipped with The detection unit a first comparator (42) for comparing the ripple component of the output voltage with a predetermined first threshold; an integrator (43) that counts the comparison result of the first comparator; a second comparator (44) for comparing the output of the integrator with a second predetermined threshold value; an electronic control device that outputs a predetermined signal when the output of the integrator exceeds the second threshold value;

2. The electronic control device according to claim 1 , wherein the detection unit outputs a signal for resetting the load as the predetermined signal.

3. The detection unit has a high-pass filter (41) that passes the ripple component of the output voltage, The electronic control device according to claim 1 , wherein the first comparator compares the ripple component that has passed through the high-pass filter with the first threshold value.

4. 2. The electronic control device according to claim 1, wherein the second threshold value is set to a value that is greater than the output of the integrator when the number of times the ripple component exceeds the first threshold value is less than a predetermined number, and is smaller than the output of the integrator when the number of times the ripple component exceeds the first threshold value is equal to or greater than the predetermined number.

5. 5. The electronic control device according to claim 4, wherein the second threshold value is set to a value that is greater than the output of the integrator when the number of times that the ripple component exceeds the first threshold value in a predetermined period is less than the predetermined number of times, and is smaller than the output of the integrator when the number of times that the ripple component exceeds the first threshold value in the predetermined period is equal to or greater than the predetermined number of times.

6. The electronic control device according to claim 5 , wherein the count of the integrator is reset if the number of times that the ripple component exceeds the first threshold is less than the predetermined number of times at the end of the predetermined period.

7. 7. The electronic control device according to claim 4, wherein the predetermined number of times is set to a number of times greater than the number of times the ripple component exceeds the first threshold value under a maximum load fluctuation condition.

8. The multiphase power supply has a coupled inductor (24C) including a plurality of the inductors; 7. The electronic control device according to claim 1, wherein the coupled inductors are arranged side by side in a predetermined direction and are magnetically coupled to each other.

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