Semiconductor integrated circuit and electronic control device

Abstract

A semiconductor integrated circuit includes: a power supply terminal to which power is supplied from an external power supply; a circuit unit including a plurality of circuits, the plurality of circuits operating at a predetermined activation rate by power supplied from the power supply terminal; a current acquisition unit that acquires, from the power supply terminal, a consumption current of the power consumed by the circuit unit; a timer that measures a cumulative operation time in which the operation time of the circuit unit is cumulated; and an omen diagnosis circuit that diagnoses a fault omen of the circuit unit on the basis of time-series data of the current consumption and the cumulative operation time acquired in time series in a diagnosis mode in which the circuit unit operates at an activation rate higher than the maximum activation rate of the normally operating circuit unit.

Description

Technical Field

[0001] The present invention relates to a semiconductor integrated circuit and an electronic control device. Background Art

[0002] Semiconductor integrated circuits, one of the semiconductor components used in vehicles, are required to guarantee even stricter reliability than consumer products. Therefore, semiconductor suppliers mass-produce automotive semiconductor integrated circuits based on their reliability assurance for vehicles. For example, for automotive use, semiconductor integrated circuits are designed for reliability to meet quality requirements for 10 years of use or 200,000 kilometers of driving. This reliability design incorporates the unique thinking of each vehicle manufacturer, assuming that the daily operating time of semiconductor integrated circuits is limited to a few hours.

[0003] The automotive industry is actively developing autonomous driving and advanced driver assistance technologies. If Level 4 or higher autonomous driving is achieved, driver control of the vehicle will be eliminated, with onboard systems handling all driving and other operations. Furthermore, beyond technological development, there is also a growing interest in expanding car-sharing services. This approach will allow for the efficient use of a vehicle's idle time, with shared use by multiple users expected to become widespread.

[0004] Patent document 1 states: "When vehicle information is received, it is identified and a diagnostic result indicating a fault is checked. If there is a fault, various data are obtained and the fault location is estimated. By determining the service sequence, it is possible to pre-arrange the corresponding components and work plans for smooth operation. In addition, if there is no fault, all vehicle information is obtained, the degradation state of the components and systems is calculated, the degradation characteristics and lifespan are estimated, and the period of service required is calculated." Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2002-322939 Summary of the Invention Problems to be solved by the invention

[0006] As mentioned above, current reliability estimates for automotive semiconductor integrated circuits assume a daily operating time of several hours. This is because vehicles are operated by humans. In the future, with the practical implementation of car-sharing and fully autonomous driving, and particularly in extreme scenarios such as automated delivery, vehicles will be expected to operate nearly 24 hours a day. In these circumstances, the lifespan of semiconductor integrated circuits, or the time to failure, will be significantly shorter than currently assumed, potentially reaching as little as one to two years.

[0007] As mentioned above, current automotive semiconductor integrated circuits are designed for reliability that can withstand 10 years of vehicle use or up to 200,000 kilometers of driving. However, designing for reliability that supports 24-hour operation is unrealistic both in terms of feasibility and cost. Meanwhile, with autonomous driving and other applications, the functions of automotive semiconductor integrated circuits, including microcomputers, are increasing. Failures in these integrated circuits can be fatal. Therefore, it is desirable to be able to detect signs of semiconductor integrated circuit failure before they occur.

[0008] Furthermore, it is known that near the end of a semiconductor integrated circuit's lifespan, wear-related failures dominate over failures caused by accidental causes. Because wear-related failures affect the operating environment of the semiconductor integrated circuit, they have the potential to occur in all circuits of the semiconductor integrated circuit. Therefore, comprehensive prognostic diagnosis, which aims to diagnose signs of semiconductor integrated circuit failure before wear-related failures, is crucial for comprehensive prognostic diagnosis covering all circuits of the semiconductor integrated circuit. Based on the above, it is important to provide a comprehensive method for diagnosing signs of semiconductor integrated circuit failure before a user implements desired measures before the semiconductor integrated circuit fails.

[0009] The present invention has been made in view of the above circumstances, and an object of the present invention is to diagnose a sign before a failure of a semiconductor integrated circuit. Technical means to solve the problem

[0010] The semiconductor integrated circuit of the present invention comprises: a power supply terminal which supplies power from an external power supply; a circuit portion which includes a plurality of circuits, and the plurality of circuits are operated at a predetermined activation rate by the power supplied from the power supply terminal; a current acquisition portion which acquires a consumption current of the power consumed by the circuit portion from the power supply terminal; a timer which measures a cumulative operating time which accumulates the time during which the circuit portion has been operating; and a sign diagnosis circuit which diagnoses a sign of failure of the circuit portion based on time series data of the consumption current and the cumulative operating time acquired in a time series in a diagnosis mode in which the circuit portion operates at an activation rate higher than the maximum activation rate of the circuit portion in normal operation. Effects of the Invention

[0011] According to the present invention, it is possible to diagnose a sign before a failure of a semiconductor integrated circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a block diagram showing an example of the internal configuration of an ECU equipped with the semiconductor integrated circuit according to the first embodiment of the present invention. Figure 2 This is a block diagram showing an example of the internal configuration of a semiconductor integrated circuit according to the first embodiment of the present invention. Figure 3 This is a flowchart showing an example of a process for performing a premature diagnosis of the semiconductor integrated circuit when the semiconductor integrated circuit according to the first embodiment of the present invention is started up. Figure 4 This is a flowchart showing an example of a process of predictive diagnosis performed by the predictive diagnosis unit of the semiconductor integrated circuit according to the first embodiment of the present invention. Figure 5 This is a graph showing changes in power supply current with respect to cumulative operating time according to the first embodiment of the present invention. Figure 6 This is a table showing the contents of time-series data stored in the memory according to the first embodiment of the present invention. Figure 7 This is a diagram showing an example of setting a warning diagnosis threshold value by the warning diagnosis circuit according to the first embodiment of the present invention. Figure 8 This is a diagram showing an example in which the early warning diagnosis circuit according to the first embodiment of the present invention performs early warning diagnosis of a semiconductor integrated circuit based on a relationship between two points. Figure 9 This is a block diagram showing an example of the hardware configuration of a computer according to the first embodiment of the present invention. Figure 10 This is a block diagram showing an example of the internal configuration of a semiconductor integrated circuit according to the second embodiment of the present invention. Figure 11 This is a flowchart showing an example of a factory test of a semiconductor integrated circuit according to the second embodiment of the present invention. Figure 12 This is a block diagram showing a configuration example of a semiconductor integrated circuit according to a third embodiment of the present invention. Figure 13 This is a flowchart showing an example of a process for changing driving control after a warning diagnosis in the semiconductor integrated circuit according to the fourth embodiment of the present invention. Figure 14 This is a flowchart showing an example of a process for identifying a main function circuit having a sign after the sign diagnosis circuit according to the fourth embodiment of the present invention performs the sign diagnosis. Figure 15 This is a flowchart showing an example of processing performed by the early-signal diagnostic unit of the semiconductor integrated circuit according to the fifth embodiment of the present invention. Figure 16 This is a block diagram showing a configuration example of a semiconductor integrated circuit according to a sixth embodiment of the present invention. Figure 17This is a flowchart showing an example of processing of predictive diagnosis and individual diagnosis performed by the predictive diagnosis unit of the semiconductor integrated circuit according to the sixth embodiment of the present invention. Figure 18 This is a block diagram showing an example of the internal configuration of an ECU equipped with a semiconductor integrated circuit according to a seventh embodiment of the present invention. Figure 19 This is a flowchart showing an example of early warning diagnosis performed by the ECU according to the seventh embodiment of the present invention. Figure 20 This is a block diagram showing an example of the internal configuration of an ECU equipped with a semiconductor integrated circuit according to an eighth embodiment of the present invention. DETAILED DESCRIPTION

[0013] Hereinafter, the mode for implementing the present invention will be described with reference to the accompanying drawings. In this specification and the accompanying drawings, the same symbols are given to the components having substantially the same function or structure, and repeated descriptions are omitted. Figures 1 to 19 The various configuration diagrams and timing diagrams are examples of embodiments of the present invention and do not limit the technical solutions. The configuration and operation of the semiconductor integrated circuits in the following embodiments are merely examples and do not limit the invention described in the technical solutions. The present invention can be applied, for example, to a computing device for vehicle control that can communicate with an onboard ECU (Electronic Control Unit) for an Advanced Driver Assistance System (ADAS) or autonomous driving (AD).

[0014] [First embodiment] First, refer to Figures 1 to 8 A semiconductor integrated circuit and a method for diagnosing a failure sign of the semiconductor integrated circuit according to a first embodiment of the present invention will be described. The semiconductor integrated circuit according to the first embodiment is mounted on an electronic control board (e.g., an ECU (Electronic Control Unit)). Furthermore, the semiconductor integrated circuit of the first embodiment diagnoses signs of failure in the main functional circuit portion of the semiconductor integrated circuit by detecting the power supply current when the circuit activation rate of the main functional circuit portion is high, thereby enabling comprehensive prognostic diagnosis of the main functional circuits within the semiconductor integrated circuit. Since the semiconductor integrated circuit of the first embodiment can diagnose signs of failure in the semiconductor integrated circuit using a single parameter (e.g., power supply current), it is possible to diagnose signs even in a short period of time, such as when the semiconductor integrated circuit is started up.

[0015] In the ECU of the first embodiment, the early warning diagnosis unit provided in the semiconductor integrated circuit calculates the reached fault current Ibreak (see the following) using the time series data stored by associating the power supply current Ipw obtained in a state where the circuit activation rate of the main function circuit unit is increased with the accumulated operating time. Figure 5 ) to the remaining life Trest_life. Based on the calculated remaining life Trest_life, the premonition diagnostic unit can diagnose whether there are signs of failure in the main functional circuit unit before the failure occurs. In the following description, the premonition diagnostic unit will simply refer to the diagnosis of the presence or absence of signs of failure in the main functional circuit unit as "diagnosing the premonition."

[0016] In addition, time series data refers to the data pairs of power supply current and the accumulated operating time corresponding to the power supply current. If there are more than one data pair, it is treated as time series data. The circuit activation rate is defined as the ratio of the number of main function circuits in operation to the total number of main function circuits. For example, in the following Figure 2 When at least one of the main function circuits 111 to 114 mounted on the main function circuit unit 11 of the semiconductor integrated circuit 1A is active, i.e., operating, the circuit activation rate is determined. A high circuit activation rate indicates a state where the circuit activation rate is higher than the maximum activation rate during normal operation of the main function circuit unit 11.

[0017] For example, assume that the main function circuit unit 11 is composed of four main function circuits 111 to 114. Furthermore, when the maximum activation rate of the main function circuit unit 11 during normal operation is 75%, the main function circuits 111 to 113 are in operation, while the main function circuit 114 is inoperative. Furthermore, when the early warning diagnosis unit 13 performs early warning diagnosis, the operation mode is switched to the diagnostic mode, and the main function circuit unit 11 operates in an operating state in which current flows through all main function circuits 111 to 114.

[0018] Below, refer to Figure 1 and Figure 2 A configuration example and an operation example of the semiconductor integrated circuit 1A and the ECU 2 incorporating the semiconductor integrated circuit 1A will be described. Figure 1 This is a block diagram showing an example of the internal configuration of the ECU 2 in which the semiconductor integrated circuit 1A according to the first embodiment is mounted.

[0019] The ECU 2 operates with power supplied from an external battery 7 and appropriately outputs a drive signal for driving the external load 6. The ECU 2 includes a semiconductor integrated circuit 1A, a power supply circuit 3, a current detection circuit 4, and a drive circuit 5.

[0020] The power supply circuit 3 converts the electric power supplied from the battery 7 and supplies the electric power to the semiconductor integrated circuit 1A and the drive circuit 5 .

[0021] The current detection circuit 4 detects the power supply current Ipw flowing through the semiconductor integrated circuit 1A based on the power supplied from the power supply circuit 3. Figure 1 The configuration shown uses a resistor 41 and a detection circuit 42. Resistor 41 is connected to power line 21, which is wired between power supply circuit 3 and semiconductor integrated circuit 1A. Resistor 41 detects power supply current Ipw and outputs the detected power supply current Ipw as a voltage. Detection circuit 42 detects the voltage generated across resistor 41 and outputs it to semiconductor integrated circuit 1A.

[0022] The semiconductor integrated circuit 1A is an example of a circuit integrating multiple semiconductors. The semiconductor integrated circuit 1A generates an optimal load drive signal for driving the load 6 based on information related to the vehicle. The load drive signal generated by the semiconductor integrated circuit 1A is output to the drive circuit 5 as a drive command. The drive circuit 5 outputs a drive signal to the load 6 according to a drive instruction from the semiconductor integrated circuit 1A.

[0023] (Example of Internal Structure of a Semiconductor Integrated Circuit) Next, an example of the internal configuration of the semiconductor integrated circuit according to the first embodiment will be described. Figure 2 1A is a block diagram showing an example of the internal structure of the semiconductor integrated circuit 1A. The semiconductor integrated circuit 1A performs a warning diagnosis of the main functional circuit unit 11 based on time series data consisting of the power supply current Ipw and the accumulated operating time of the semiconductor integrated circuit 1A.

[0024] The semiconductor integrated circuit 1A includes a power supply terminal 10 , a main function circuit unit 11 , a main function control circuit 12 , and a warning sign diagnostic unit 13 . The power supply terminal 10 is connected to the power supply line 21. Power is supplied from the external power supply (battery 7) to the power supply terminal (power supply terminal 10). Then, the power supply terminal 10 transmits the power of the battery 7 through the power supply line 21 (see Figure 1 ) are output to various parts within the semiconductor integrated circuit 1A.

[0025] The circuit unit (main function circuit unit 11) includes multiple circuits, and the multiple circuits operate at a predetermined activation rate using the power supplied from the power supply terminal (power supply terminal 10). The main function circuit unit 11 has the main function of generating a load drive signal for the load 6. The main function circuit unit 11 is a circuit group that includes various circuits required for generating a load drive signal during normal operation, performing initialization operations when starting the semiconductor integrated circuit 1A, and performing hardware self-diagnosis operations. The main function circuit unit 11 has main function circuits 111 to 114 as an example of multiple semiconductor circuits. The main function circuits 111 to 114 operate independently based on the power supplied through the power line 21.

[0026] The main function control circuit 12 controls the operation of the main function circuit unit 11. This circuit controls circuit operation according to the startup sequence during startup of the semiconductor integrated circuit 1A and controls the circuit activation rate during early warning diagnosis. The main function control circuit 12 controls the operation of the main function circuits 111 to 114 according to the operating mode. In normal mode, the main function control circuit 12 selects a desired main function circuit from among the main function circuits 111 to 114 and activates it.

[0027] On the other hand, in the diagnostic mode, the main function control circuit 12 causes all the main function circuits 111 to 114 to operate. In addition, in the diagnostic mode, the main function control circuit 12 notifies the pre-diagnosis unit 13 that it is the diagnostic mode. The pre-diagnosis unit 13 receives the notification from the main function control circuit 12 and performs pre-diagnosis. In the following description, performing pre-diagnosis of the main function circuit unit 11 is synonymous with performing pre-diagnosis of the semiconductor integrated circuit 1A. In addition, the pre-diagnosis of the semiconductor integrated circuit 1A needs to be performed in a manner that does not affect the normal use of the semiconductor integrated circuit 1A. Therefore, the diagnosis of the fault signs based on the diagnostic mode is performed when the semiconductor integrated circuit (semiconductor integrated circuit 1A) is started or ended.

[0028] The early warning diagnostic unit 13 diagnoses a failure sign in the semiconductor integrated circuit 1A. The early warning diagnostic unit 13 includes a timer 131, a current acquisition unit 132, a memory 133, and an early warning diagnostic circuit 134. When the semiconductor integrated circuit 1A is in the diagnostic mode, the early warning diagnostic unit 13 operates.

[0029] The timer (timer 131) measures the cumulative operating time obtained by accumulating the time the circuit unit (main function circuit unit 11) is running. For example, the timer 131 regards the time when the semiconductor integrated circuit 1A is started, that is, the time when the power supply voltage is applied to the power supply terminal of the semiconductor integrated circuit 1A as the operating time of the semiconductor integrated circuit 1A, and measures the cumulative operating time Tacc which is the accumulated operating time. During the startup of the semiconductor integrated circuit 1A, the main function circuit unit 11 is running, so the operating time is accumulated in the cumulative operating time Tacc. Then, the timer 131 outputs the data of the cumulative operating time Tacc to the memory 133. In addition, the timer 131 can also read the cumulative operating time Tacc from the memory 133 when the semiconductor integrated circuit 1A is started, accumulate time in the read cumulative operating time Tacc during the startup of the semiconductor integrated circuit 1A, and output the cumulative operating time Tacc to the memory 133 when the semiconductor integrated circuit 1A is stopped.

[0030] The current acquisition unit (current acquisition unit 132) acquires the current consumption of the power consumed in the circuit unit (main function circuit unit 11) from the power supply terminal (power supply terminal 10). For example, the current acquisition unit 132 acquires the power supply current when the circuit activation rate of the main function circuit unit 11 is high. The power supply current acquired by the current acquisition unit 132 is Figure 1 The current detection circuit 4 shown in the figure represents the voltage Vsense_pw output based on the power supply current Ipw. The current acquisition unit 132 is composed of, for example, an ADC (Analog to Digital Converter). The current acquisition unit 132 converts the voltage Vsense_pw detected by the current detection circuit 4 into data and outputs it to the memory 133. To avoid affecting the normal operation of the semiconductor integrated circuit 1A, the current acquisition unit 132 acquires the power supply current Ipw at the start-up or shutdown of the semiconductor integrated circuit 1A. However, the current acquisition unit 132 may also acquire the power supply current Ipw periodically, as long as it does not affect normal operation.

[0031] The memory (memory 133) stores time-series data on current consumption and accumulated operating time acquired in diagnostic mode. For example, memory 133 stores time-series data that associates the power supply current Ipw with the accumulated operating time Tacc at the time the current acquisition unit 132 acquires the power supply current Ipw. The period during which memory 133 stores accumulated operating time Tacc is preferably several months to several years. Therefore, memory 133 uses a non-volatile storage medium such as flash memory that can retain data even when the power is off.

[0032] The early warning diagnosis circuit (early warning diagnosis circuit 134) diagnoses early warning signs of failure in the circuit unit (main functional circuit unit 11) based on time-series data of current consumption and accumulated operating time acquired in a diagnostic mode in which the circuit unit (main functional circuit unit 11) operates at an activation rate higher than the maximum activation rate of the circuit unit (main functional circuit unit 11) during normal operation. Furthermore, the early warning diagnosis circuit (early warning diagnosis circuit 134) calculates the time at which the current consumption acquired in the diagnostic mode reaches a early warning diagnosis threshold based on the time-series data of current consumption and accumulated operating time, thereby predicting the timing of failure in the circuit unit (main functional circuit unit 11).

[0033] For example, the sign diagnosis circuit 134 calculates the time transition of the power supply current Ipw based on the time series data of the power supply current Ipw and the accumulated operating time Tacc stored in the memory 133 during the sign diagnosis. In addition, after calculating the remaining life Trest_life of the semiconductor integrated circuit 1A, the sign diagnosis circuit 134 uses the remaining life Trest_life to diagnose the presence or absence of a failure sign of the semiconductor integrated circuit 1A. A failure sign is a symptom that appears before a semiconductor integrated circuit fails. For example, if any one of the main functional circuits 111 to 114 deteriorates and the power supply current Ipw approaches the failure current Ibreak, it is a sign of failure. By comparing the remaining life Trest_life with the Figure 3 The presence or absence of a fault sign is diagnosed based on the relationship between the sign diagnosis threshold value Tth_symptom shown in FIG.

[0034] <Example of Predictive Diagnosis Processing> Next, an example of a process for executing the early-signal diagnosis of the semiconductor integrated circuit 1A will be described. Figure 3 1A is a flowchart showing an example of a process for performing a warning diagnosis of the semiconductor integrated circuit 1A when the semiconductor integrated circuit 1A is started up. Figure 3 In the following, the processing performed from the start-up to the end of the semiconductor integrated circuit 1A is described.

[0035] When the user turns on the vehicle power (turns on the ignition switch), this process starts and the semiconductor integrated circuit 1A starts up (S1-1). Then, power from the battery 7 starts to be supplied to the semiconductor integrated circuit 1A via the power supply circuit 3, and the process proceeds to S1-2.

[0036] Next, the operation of the timer 131 for acquiring the accumulated operating time Tacc is started, and data setting of initial values ​​of registers within the semiconductor integrated circuit 1A is performed ( S1 - 2 ), and the process proceeds to S1 - 3 .

[0037] Next, the semiconductor integrated circuit 1A performs a self-diagnosis of the hardware within the semiconductor integrated circuit 1A (S1-3) and proceeds to S1-4. Here, the semiconductor integrated circuit 1A confirms whether the main function circuits 111 to 114 are operating normally and whether the early warning diagnosis circuit 134 is also operating normally.

[0038] Next, the early warning diagnosis unit 13 of the semiconductor integrated circuit 1A performs early warning diagnosis of the semiconductor integrated circuit 1A in the diagnosis mode (S1-4) and calculates the remaining life Trest_life. The details of the processing of S1-4 will be described later. Figure 4 Provide explanation.

[0039] After S1-4, the premonition diagnostic unit 13 determines whether there are any signs of a failure in the main functional circuit unit 11 (S1-5). Here, the premonition diagnostic unit 13 performs premonition diagnosis by comparing the remaining lifespan Trest_life with the premonition diagnostic threshold Tth_symptom. If the remaining lifespan Trest_life is less than the premonition diagnostic threshold Tth_symptom, the premonition diagnostic unit 13 diagnoses that a premonition is present ("Yes" in S1-5) and proceeds to S1-7. On the other hand, if the remaining lifespan Trest_life is greater than the premonition diagnostic threshold Tth_symptom, the premonition diagnostic unit 13 diagnoses that there are no premonitions ("No" in S1-5) and proceeds to S1-6.

[0040] After a "yes" determination in S1-5, the premonition diagnostic unit 13 notifies the vehicle user of the vehicle (S1-7) via an in-vehicle warning light or the like, indicating that the main function circuit unit 11 has a premonition of failure, and then proceeds to S1-6. Furthermore, even after the premonition diagnostic unit 13 diagnoses that the main function circuit unit 11 has a premonition, the vehicle can still be driven. Therefore, it is assumed that the user can take the countermeasure of allowing the vehicle to drive itself and entrusting a repairman to inspect and replace the ECU 2. However, if it is determined that there is a premonition of failure while the vehicle is driving, the user can also immediately stop the vehicle and entrust a repairman to move the vehicle using a tow truck.

[0041] After a "No" determination in S1-5 or S1-7, the semiconductor integrated circuit 1A performs normal operation in the normal operation mode (S1-6). During normal operation, the voltage anomaly detection circuit (not shown) included in the main function circuit unit 11 monitors the power supply voltage Vpw of the main function circuits 111 to 114. If the power supply voltage Vpw falls below a voltage threshold Vmin_ope, which is the minimum voltage at which the main function circuits 111 to 114 can operate, the main function control circuit 12 shuts down the main function circuits 111 to 114.

[0042] Next, the semiconductor integrated circuit 1A determines whether the ignition is off (S1-8). Here, the semiconductor integrated circuit 1A compares the power supply voltage Vpw with the low-voltage threshold Vmin_ope to determine whether the user has turned off the vehicle's ignition. When the ignition switch is off, the voltage supply from the battery 7 to the ECU 2 stops, and the power supply voltage Vpw falls below the low-voltage threshold Vmin_ope.

[0043] Here, if the power supply voltage Vpw is greater than or equal to the low voltage threshold value Vmin_ope, the semiconductor integrated circuit 1A determines that the ignition is not off (No in S1-8) and proceeds to S1-6 to continue normal operation. On the other hand, if the power supply voltage Vpw is less than the low voltage threshold value Vmin_ope, the semiconductor integrated circuit 1A determines that the ignition is off (Yes in S1-8), stops normal operations such as generation of the load drive signal, and proceeds to S1-9.

[0044] After a "Yes" determination is made in S1-8, the semiconductor integrated circuit 1A performs a series of shutdown processes (S1-9), such as storing the data to be recorded in the memory 133 and stopping the operation of the timer 131 for acquiring the accumulated operating time Tacc. After the shutdown processes are completed, all internal circuits of the ECU 2 are stopped (S1-10).

[0045] Since the circuit activation rate of the main function circuit unit 11 is high, Figure 3 The early warning diagnosis process shown in step S1-4 is preferably performed after S1-3 when all hardware (internal circuits) are operational, as described above.

[0046] In this embodiment, the user is notified of a failure sign as a process after the predictive diagnosis. However, if the semiconductor integrated circuit 1A is connected to an external system via OTA (Over The Air) or other communication technology, the predictive diagnosis unit 13 can notify the external system of the failure sign. Furthermore, while the user is notified of a failure sign in this embodiment, the remaining life Trest_life can also be notified to the user each time the predictive diagnosis unit 13 performs a predictive diagnosis.

[0047] in addition, Figure 3The flowchart shown is an example of the startup process for the semiconductor integrated circuit 1A in this embodiment. However, the content and order of the processes may vary for each semiconductor integrated circuit, and some processes may be added or deleted. Furthermore, while this embodiment shows an example of performing a pre-diagnosis during startup of the semiconductor integrated circuit 1A, it may also be performed during shutdown of the semiconductor integrated circuit 1A. Furthermore, pre-diagnosis may be performed periodically during normal operation, to the extent that it does not affect normal operation.

[0048] <Processing of Premonition Diagnosis> Next, the prognostic diagnosis ( Figure 3 An example of detailed processing of S1-4) in the flowchart is described. Figure 4 This is a flowchart showing an example of the process of the early warning diagnosis performed by the early warning diagnosis unit 13 of the semiconductor integrated circuit 1A. As described above, the early warning diagnosis process starts when the hardware self-diagnosis (S1-3) is completed. As described above, Figure 4 The illustrated prognostic diagnosis process is performed in a diagnostic mode.

[0049] First, the main function control circuit 12 controls the circuit activation rate of the main function circuit unit 11 to a state higher than the circuit activation rate during normal operation of the semiconductor integrated circuit (S1-41), and then enters S1-42. Here, controlling the current flowing through all main function circuits 111 to 114 is referred to as "controlling to a state higher than the circuit activation rate during normal operation."

[0050] Next, the current acquisition unit 132 of the early warning diagnostic unit 13 simultaneously acquires the voltage Vsense_pw containing power supply current information from the current detection circuit 4 and acquires the accumulated operating time data Dt from the timer 131 (S1-42), and then proceeds to S1-43. "Having power supply current information" means that the current acquisition unit 132 can detect the power supply current based on the magnitude of the voltage, since the voltage is measured in proportion to the power supply current.

[0051] The timer 131's process of storing the accumulated operating time data Dt in the memory 133 occurs at a different time than the current acquisition unit 132's process of acquiring the voltage Vsense_pw, due to the timing used to convert the accumulated operating time Tacc into the accumulated operating time data Dt. However, the acquisition of the voltage Vsense_pw and the acquisition of the accumulated operating time data Dt are simultaneous. Data input to the ADC typically used in the current acquisition unit 132 uses a circuit such as a sample-and-hold circuit to temporarily hold the acquired data. By synchronizing the acquisition of the voltage Vsense_pw containing the power supply current information and the reading of the accumulated operating time data Dt by the sample-and-hold circuit, the acquisition of the voltage Vsense_pw containing the power supply current information from the current detection circuit 4 and the acquisition of the accumulated operating time data Dt from the timer 131 can be considered to be executed simultaneously.

[0052] Next, the current acquisition unit 132 converts the voltage Vsense_pw AD having the power supply current information into power supply current data Di that can be stored in the memory 133 ( S1 - 43 ), and proceeds to S1 - 44 . Next, the current acquisition unit 132 associates the power supply current data Di and the accumulated operating time data Dt with each other and stores them in the memory 133 ( S1 - 44 ), and then proceeds to S1 - 45 .

[0053] Next, the main function control circuit 12 returns from the diagnostic mode to the normal mode. The main function control circuit 12 then returns the circuit activation rate of the main function circuit unit 11 to the circuit activation rate during normal operation (S1-45), and proceeds to S1-46.

[0054] Next, the prediction diagnosis circuit 134 performs a prediction diagnosis to calculate the remaining life Trest_life (S1-46), and then enters the Figure 3 In this early warning diagnosis, the early warning diagnosis circuit 134 obtains the following information from the memory 133. Figure 6 The necessary data is read from the power supply current data column Di_col, which includes past power supply current data Di, and the cumulative operating time data column Dt_col at the time the current acquisition unit 132 acquires each power supply current. The early warning diagnosis circuit 134 then calculates the remaining life Trest_life until the power supply current reaches the fault current Ibreak based on the data read from the power supply current data column Di_col and the cumulative operating time data column Dt_col. The fault current Ibreak is the current value detected when the main functional circuit unit 11 is clearly diagnosed as having a fault. The process by which the early warning diagnosis circuit 134 calculates the remaining life Trest_life will be described later.

[0055] Furthermore, if the premonition diagnosis circuit 134 is a main function circuit that is inactivated under the control of S1-41, it cannot capture the time transition of the current consumption using the power supply current, and therefore cannot perform premonition diagnosis for the inactivated main function circuit. Therefore, the higher the circuit activation rate in the main function circuit unit 11 controlled by S1-41, the more main function circuits can capture premonitions using the power supply current, and thus the premonition diagnosis becomes more comprehensive.

[0056] <Processing of Calculating Remaining Life by the Predictive Diagnosis Circuit> Next, refer to Figure 5 and Figure 6 The early warning diagnosis circuit 134 is Figure 4 An example of a process of calculating the remaining life Trest_life based on the data in the cumulative operating time data column Dt_col and the data in the power supply current data column Di_col shown in the early warning diagnosis of S1-46 will be described. Figure 5 and Figure 6 The data shown is generated for performing a warning diagnosis of the main functional circuit unit 11 .

[0057] Figure 5 This is a graph showing the change in power supply current Ipw relative to the cumulative operating time Tacc. Figure 5 In the graph shown, the accumulated operating time Tacc is plotted on the X-axis and the power supply current Ipw is plotted on the Y-axis. Figure 6 The graph shows the time series data (Dt_col, Di_col) stored in the memory 133 from the start time of use of the semiconductor integrated circuit 1A (Tacc=T1=0) to the current time (T9). Figure 6 The time series data (Dt_col, Di_col) shown in FIG. 1 is the time series data (Dt_col, Di_col). The predicted fault time (Tbreak) (T10) is later than the current time (Tcur) (T9), but in order to explain the remaining life Trest_life and the fault current Ibreak, Figure 5 .

[0058] Figure 6 This table shows the contents of the time series data (Dt_col, Di_col) stored in the memory 133. In the memory 133, the data of the cumulative operation time column DT_col and the power supply current data column Di_col are stored in the order of T1, T2, ..., T9, which are the predictive diagnosis times.

[0059] At the current moment (T9), in the semiconductor integrated circuit 1A, the main functional circuit unit 11 begins to consume more current due to a change in its characteristics over time. This increase in current consumption is caused by degradation in the main functional circuit unit 11, which causes an increase in current consumption as the cumulative operating time Tacc increases. As this degradation in the main functional circuit unit 11 increases, the power supply current Ipw consumed by the main functional circuit unit 11 also increases. Therefore, by storing the power supply current Ipw and the cumulative operating time Tacc in association with each other in the memory 133, the early warning diagnostic circuit 134 can understand the temporal trend of the power supply current Ipw caused by the change in the main functional circuit unit 11's characteristics over time.

[0060] Specifically, the early warning diagnosis circuit 134 can predict the future time transition based on the time transition trend of the power supply current Ipw. Furthermore, the early warning diagnosis circuit 134 can calculate the time Tbreak until the power supply current Ipw reaches the fault current Ibreak based on the predicted time transition. One example of a method for calculating the future time transition based on the time transition trend is a method using an approximate formula.

[0061] In this embodiment, as an example of an approximation formula, a method of performing prediction using exponential approximation in which the cumulative operating time represented by the following formula (1) is represented as x and the power supply current is represented as y is described.

[0062] y=a×e^(bx)…(1) In formula (1), e is the Napier constant, a and b are coefficients of the exponential approximation, x is the cumulative operating time Tacc, and y is the power supply current Ipw.

[0063] Here, in Figure 5 At each time of the cumulative operation time T1 to T9 in the prediction diagnosis circuit 134, the prediction diagnosis is performed. Figure 6 The time series data (Dt_col, Di_col) shown is stored in the memory 133. The method of calculating the remaining life Trest_life by the early warning diagnosis circuit 134 will be described. In addition, since the method of calculating the coefficients of the approximate formula is well known, the description thereof will be omitted.

[0064] First, based on the time-series data (DT_col, Di_col) read from memory 133, early warning diagnostic circuit 134 uses data from T4 onward, immediately before the onset of degradation, to calculate the coefficients a and b in equation (1): a = 47.646, b = 0.008. In the approximate equation incorporating the coefficients a and b, y represents the fault current Ibreak, and x represents the cumulative operating time until the fault current reaches its peak, i.e., the cumulative operating time to the end of service life, Tbreak.

[0065] Here, the predictive diagnostic circuit 134 calculates the cumulative operating time Tbreak by finding x when y = fault current Ibreak. Furthermore, the predictive diagnostic circuit 134 calculates the remaining life Trest_life as the difference between the cumulative operating time Tbreak and the current cumulative operating time Tcur. For example, if Tcur = T9, the predictive diagnostic circuit 134 calculates T10 - T9 as the remaining life Trest_life. In this way, the predictive diagnostic circuit 134 can calculate the remaining life Trest_life using time-series data and approximate equation (1).

[0066] like Figure 5 As shown, the fault current Ibreak is set in advance to a value greater than the initial value Iini. Furthermore, the early warning diagnosis circuit 134 calculates the remaining life Trest_life until the power supply current Ipw reaches the fault current Ibreak, thereby performing early warning diagnosis effective for a degradation pattern in which the power supply current Ipw increases.

[0067] On the other hand, the power supply current Ipw may decrease as the main functional circuit unit 11 degrades. In this case, the fault current Ibreak is set to a value smaller than the initial value Iini. Furthermore, the premonition diagnosis circuit 134 may calculate the remaining lifespan Trest_life until the power supply current Ipw reaches the fault current Ibreak. In this case, the premonition diagnosis is effective for degradation patterns in which the power supply current Ipw decreases. Alternatively, the premonition diagnosis circuit 134 may set the fault current Ibreak to both a value greater than and a value less than the initial value Iini, enabling detection of both degradation patterns in which the power supply current Ipw increases and degradation patterns in which the power supply current Ipw decreases.

[0068] Furthermore, the fault current Ibreak can be set during the manufacture of the semiconductor integrated circuit 1A, and cannot be changed after the semiconductor integrated circuit 1A is installed in the vehicle. Furthermore, if the semiconductor integrated circuit 1A is connected to an external system via an OTA or other means, the fault current Ibreak can be changed based on a value received from the external system even after the semiconductor integrated circuit 1A is installed in the vehicle.

[0069] <Processing of Changing the Predictive Diagnosis Threshold> Furthermore, when the slope of the time series data is larger than a predetermined slope, the predictive diagnosis threshold value Tth_symptom may be changed. Figure 7 1 is a diagram showing an example of how the early-sign diagnosis circuit 134 sets the early-sign diagnosis threshold value. Figure 7Graph (1) shows an example of changes in the power supply current Ipw when the degradation rate of the main functional circuit unit 11 is fast. Figure 7 Graph (2) shows an example of the change in the power supply current Ipw under normal conditions of the degradation rate of the main functional circuit unit 11. In addition, the star mark in the figure indicates the predicted failure period when the power supply current Ipw reaches the failure current Ibreak.

[0070] When the degradation rate of the main functional circuit unit 11 is normal, as shown in FIG. Figure 7 As shown in Graph (2), even if the power supply current Ipw increases, the remaining life Trest_life until the fault current Ibreak is reached is sufficiently long. Furthermore, the pre-diagnosis threshold Tth_symptom is set to a predetermined value. Therefore, the time at which a failure sign is presented to the user is set to the time at which the pre-diagnosis threshold Tth_symptom is reached, looking back from the predicted failure period (T10).

[0071] On the other hand, when the degradation rate of the main functional circuit unit 11 is fast, as shown in FIG. Figure 7 As shown in the graph (1), the power supply current Ipw increases in a short period of time. Therefore, the remaining life Tres t_life until the power supply current Ipw reaches the fault current Ibreak is Figure 7 The remaining life Trest_life shown in the graph (2) is short. However, if the repair of the main function circuit unit 11 cannot be completed before the predicted failure period, the vehicle may stop at a time not intended by the user. In this case, the early warning diagnosis circuit 134 needs to notify the user of the early warning of failure earlier than usual or change the vehicle control method for safety reasons.

[0072] Here, the sign diagnosis circuit (sign diagnosis circuit 134) changes the sign diagnosis threshold value based on the slope of the consumption current relative to the accumulated operating time of the time series data. For example, when the degradation progresses rapidly, the sign diagnosis circuit 134 changes the sign diagnosis threshold value Tth_symptom based on the steep slope of the time series data. For example, if the slope of the two moments (T8 and T9) immediately before the slope of the time series data is calculated is "5" or more, the sign diagnosis circuit 134 sets the sign diagnosis threshold value Tth_symptom to a value higher than the slope of the time series data. Figure 7 The slopes of T8 and T9 are expressed by the following formula. Slope of T8 and T9 = [Di_col(T9)-Di_col(T8)] / [DT_col(T9)-DT_col(T8)]

[0073] Thus, when the slope of the time-series data is larger than usual, early warning diagnosis circuit 134 sets early warning diagnosis threshold Tth_symptom to a larger value. In other words, early warning diagnosis circuit 134 increases early warning diagnosis threshold Tth_symptom as the rate of degradation increases. This allows early warning diagnosis circuit 134 to notify the user of a failure sign earlier than usual and to implement safety controls such as changing vehicle control methods.

[0074] <Modification of Power Supply Current Data Stored in Memory> In addition, instead of storing all the power supply current data acquired in the past predictive diagnosis in the memory 133, only the power supply current data effective for the predictive diagnosis may be stored in the memory 133. Figure 5 Since the time-dependent characteristic variation of the main functional circuit unit 11 cannot be confirmed during the period from T2 to T3, the power supply current data for the period from T2 to T3 does not need to be retained in the memory 133. On the other hand, the value of the initial current at T1 required for calculating the coefficients of the approximate formula (1), the power supply current data acquired immediately before T5 (T4) when the time-dependent characteristic variation of the semiconductor integrated circuit 1A is observed, and the data of the cumulative operating time Tacc and the power supply current Ipw acquired after T4 are stored in the memory 133. By limiting the data stored in the memory 133, only the data required for the early warning diagnosis can be retained in the memory 133, and the amount of data in the memory 133 can be reduced.

[0075] The above method uses the time-series data (Dt_col, Di_col) from memory 133 to calculate the remaining life Trest_life by calculating the cumulative operating time Tbreak until the fault current Ibreak. This method performs a predictive diagnosis by predictive diagnosis circuit 134, and requires that the cumulative operating time Tacc corresponding to the power supply current Ipw be stored in memory 133 to ensure that the predictive diagnosis is performed by predictive diagnosis circuit 134. Therefore, memory 133 must be rewritable.

[0076] (Example of a semiconductor integrated circuit without a memory) On the other hand, for semiconductor integrated circuits that are not equipped with rewritable memory 133, the prognostic diagnosis circuit 134 can also perform prognostic diagnosis using the method described below. First, the prognostic diagnosis circuit 134 calculates the difference between the initial value of the power supply current obtained when the semiconductor integrated circuit is manufactured and the power supply current obtained when the semiconductor integrated circuit is installed in a vehicle and used. Thereafter, the prognostic diagnosis circuit 134 performs prognostic diagnosis based on the difference in power supply current and the accumulated operating time Tacc. In this method, the initial value Iini of the power supply current obtained during the manufacturing process is recorded in a ROM (Read Only Memory) such as an OTP (One Time Programmable Memory). By recording the initial value Iini in the ROM, it is no longer necessary to store the power supply current Ipw and the accumulated operating time Tacc at the time of acquisition in the rewritable memory 133 for each prognostic diagnosis, and thus the memory 133 is no longer required.

[0077] <Method for calculating remaining life using a two-point relationship> In addition, if from Figure 2 The semiconductor integrated circuit 1A shown does not require the memory 133, so the accumulated operating time data Dt acquired by the timer 131 and the power supply current data Di acquired by the current acquisition unit 132 are directly input to the early warning diagnosis circuit 134, and early warning diagnosis is performed. Figure 8 An example of the operation of the predictive diagnosis circuit 134 using the initial value Iini of the power supply current, the power supply current data Di acquired during the predictive diagnosis, and the accumulated operating time data Dt for performing a predictive diagnosis will be described. Furthermore, the example of the operation of the predictive diagnosis circuit 134 will be described assuming that the current time (Tcur) during the predictive diagnosis is time T9.

[0078] Figure 8 This diagram illustrates an example of how the prediction diagnostic circuit 134 performs a prediction diagnosis of the semiconductor integrated circuit 1A based on the relationship between power supply currents acquired at two different points at different time periods. In this example, the prediction diagnostic circuit 134 calculates the remaining lifetime based on the relationship between the initial power supply current value and the power supply current value acquired after a predetermined period of time, thereby performing a prediction diagnosis of the semiconductor integrated circuit 1A. Figure 8 T1, T9, and T10 are all related to Figure 5 T1, T9, and T10 are the same moments.

[0079] In this example, when the semiconductor integrated circuit 1A is manufactured (at time T1), the current acquisition unit 132 acquires the initial value Iini of the power supply current. Here, the initial value Iini is set as the power supply current data Di1. In addition, after the semiconductor integrated circuit 1A is mounted on the vehicle, the current acquisition unit 132 acquires the power supply current data Di when the semiconductor integrated circuit 1A is started. Here, the current acquisition unit 132 is set as the power supply current data Di1. Figure 5 The power supply current value acquired at the same time as the time T9 shown is set as the power supply current data Di9. In addition, the data of the cumulative operation time Tacc at the time T9 is set as the cumulative operation time data DT9.

[0080] The early warning diagnosis circuit 134 can calculate the remaining life by linear approximation between two points using the power supply current data Di9, the accumulated operating time data DT9, and the following equation (2). The method for calculating the coefficients of the approximation equation (2) is well known, so its description is omitted. y=a×x+b…(2)

[0081] As the initial value Iini, we get Figure 6 The same power supply current Ipw and cumulative operating time Tacc at time T1 are obtained. Figure 6 The same power supply current Ipw and cumulative operating time Tacc are used as at time T9. In this case, the coefficients a and b in equation (2) are obtained as a=0.00056 and b=50. The method by which the omen diagnosis circuit 134 calculates the remaining life Trest_life using the approximate equation (2) is the same as when the omen diagnosis circuit 134 uses equation (1) to predict the remaining life by exponential approximation, so detailed description is omitted. If it is referenced Figure 8 The method described above does not require the semiconductor integrated circuit 1A to be equipped with the rewritable memory 133, and thus the circuit area of ​​the semiconductor integrated circuit 1A can be reduced.

[0082] If the memory area in the semiconductor integrated circuit 1A cannot be increased, a method using linear approximation between two points is effective. On the other hand, the method using equation (2) to predict the remaining life Trest_life is a linear approximation between two points, so the accuracy of the predictive diagnosis is lower than that of the remaining life Trest_life calculated using exponential approximation using equation (1). Thus, there is a trade-off between the memory area and the accuracy of the remaining life prediction.

[0083] For example, if at time T7 (refer to Figure 5) Using approximate equation (2) results in a smaller slope of the straight line between the two points. Consequently, the time it takes for the power supply current Ipw to reach the fault current Ibreak becomes longer, making it easier to calculate a longer remaining lifespan Trest_life than when using approximate equation (1). However, even if the remaining lifespan Trest_life is somewhat inaccurate, it serves as a guide for the lifespan of the semiconductor integrated circuit 1A. Therefore, the user can know in advance when to replace or repair the semiconductor integrated circuit 1A without any problems.

[0084] <Computer Hardware Configuration Example> Next, the hardware configuration of the computer 50 constituting the ECU 2 will be described. Figure 9 This is a block diagram showing an example of the hardware configuration of the computer 50. The computer 50 is an example of hardware used as a computer capable of operating as the ECU 2 of this embodiment. The ECU 2 of this embodiment is implemented by the computer 50 (computer) executing a program. Figure 3 and Figure 4 The functional units shown cooperate to perform a predictive diagnosis method.

[0085] The computer 50 includes a CPU (Central Processing Unit) 51 , a ROM (Read Only Memory) 52 , and a RAM (Random Access Memory) 53 , each of which is connected to a bus 54 . The computer 50 also includes a nonvolatile memory 55 and a network interface 56 .

[0086] The CPU 51 reads the program code of the software that realizes each function of this embodiment from the ROM 52, loads it into the RAM 53, and executes it. In the RAM 53, variables and parameters generated during the operation processing of the CPU 51 are temporarily written, and these variables and parameters are read by the CPU 51 as appropriate. Figure 2 Each functional unit of the semiconductor integrated circuit 1A shown is implemented by a CPU 51. However, an MPU (Micro Processing Unit) or a GPU (Graphics Processing Unit) may be used instead of the CPU 51, or the CPU 51 and the GPU may be used in combination.

[0087] Nonvolatile memory 55 is, for example, an HDD (Hard Disk Drive), an SSD (Solid State Drive), an optical disk, a magneto-optical disk, or a nonvolatile memory. In addition to the OS (Operating System) and various parameters, nonvolatile memory 55 also stores programs for operating computer 50. ROM 52 and nonvolatile memory 55 store programs and data necessary for the operation of CPU 51 and are used as examples of computer-readable, non-transitory storage media that store programs executed by computer 50.

[0088] The network interface 56 uses, for example, a NIC (Network Interface Card) and can transmit and receive various data between ECUs via a CAN (Controller Area Network) connected to a terminal of the NIC, a dedicated line, or the like.

[0089] In the semiconductor integrated circuit 1A and ECU 2 of the first embodiment described above, the premonition diagnostic unit 13 associates the power supply current Ipw, obtained while the circuit activation rate of the main functional circuit unit 11 is increased, with the accumulated operating time Tacc, and stores the time-series data (Dt_col, Di_col) in the memory 133. The premonition diagnostic circuit 134 then calculates the accumulated operating time Tacc until the power supply current Ipw reaches the fault current Ibreak based on the time-series data read from the memory 133. The premonition diagnostic circuit 134 then calculates the remaining life Trest_life until the power supply current Ipw reaches the fault current Ibreak by taking the difference between the accumulated operating time Tacc and the current time. The comparison of the remaining life Trest_life with the premonition diagnostic threshold Tth_symptom allows diagnosis of the presence of a premonition of failure in the main functional circuit unit 11.

[0090] When the early warning diagnosis circuit 134 diagnoses a fault early warning, it notifies the user of the fault early warning. Therefore, before the main function circuit unit 11 fails, the user can be aware of the possibility of failure of the main function circuit unit 11 and can take measures such as repairing or replacing the semiconductor integrated circuit 1A including the main function circuit unit 11.

[0091] Furthermore, since a failure sign is diagnosed for each of the plurality of semiconductor integrated circuits 1A mounted on the vehicle, only the semiconductor integrated circuit 1A for which a failure sign has been notified needs to be repaired or replaced, thereby reducing the time and cost required for repairing or replacing the semiconductor integrated circuit 1A.

[0092] Furthermore, in the first embodiment, the process of acquiring the power supply current Ipw and the accumulated operating time Tacc, and the process of diagnosing a failure sign are both performed when the semiconductor integrated circuit 1A is powered on and starts up. However, the respective processes may be performed at different times. For example, the failure sign diagnosis unit 13 may temporarily switch to a diagnostic mode during normal operation of the semiconductor integrated circuit 1A, periodically acquiring the power supply current Ipw and the accumulated operating time Tacc, and performing a failure sign diagnosis when the ECU 2 terminates.

[0093] In the first embodiment, the ECU 2 is described as an example of a system equipped with the semiconductor integrated circuit 1A. However, the system equipped with the semiconductor integrated circuit is not limited to the ECU as long as it can be equipped with a semiconductor integrated circuit such as an inverter.

[0094] So far, the process of performing a premonition diagnosis on the main function circuit unit 11 as the premonition diagnosis object has been described. This is because voltage is applied only to the main function circuit unit 11 through the power supply terminal 10. However, in addition to the main function circuit unit, the premonition diagnosis circuit unit can also apply voltage through the power supply terminal 10 to perform premonition diagnosis on both the main function circuit unit and the premonition diagnosis circuit unit. In this case, the current obtained by combining the consumption current of the main function circuit unit and the consumption current of the premonition diagnosis circuit unit flows into the power supply terminal 10 as the power supply current. Furthermore, if premonition diagnosis is performed using the power supply current obtained by combining the consumption currents of the main function circuit unit and the premonition diagnosis circuit unit, premonition diagnosis can be performed on both the main function circuit unit 11 and the premonition diagnosis circuit unit.

[0095] [Second embodiment] Next, refer to Figure 10 and Figure 11 The following describes a configuration example of a semiconductor integrated circuit and a predictive diagnostic method according to a second embodiment of the present invention. In this second embodiment, the semiconductor integrated circuit acquires an initial value of the power supply current during ECU manufacturing, taking into account variations in the power supply current supplied from the power supply circuit to the semiconductor integrated circuit due to manufacturing variations in the ECU. While manufacturing variations may also occur outside the ECU, this second embodiment assumes manufacturing variations within the ECU.

[0096] In the semiconductor integrated circuit of the second embodiment, in addition to the functional units that constitute the semiconductor integrated circuit of the first embodiment, a fault current is set based on the initial value of the power supply current acquired by the semiconductor integrated circuit during ECU manufacturing. The configuration example of the semiconductor integrated circuit of the second embodiment and the method for setting the initial value of the power supply current are designed to perform pre-diagnosis using a pre-diagnosis threshold that takes into account variations in the power supply current associated with ECU manufacturing variations. The following description focuses on the differences from the first embodiment.

[0097] (Configuration Example of Semiconductor Integrated Circuit According to Second Embodiment) Here, an example of a semiconductor integrated circuit according to the second embodiment of the present invention is given. Figure 10 The structure of the semiconductor integrated circuit 1B shown. Figure 10 This is a block diagram showing an example of the internal configuration of a semiconductor integrated circuit 1B according to the second embodiment.

[0098] The semiconductor integrated circuit 1B includes a main function circuit unit 11 , a main function control circuit 12 , and a warning sign diagnostic unit 13B. The warning sign diagnostic unit 13B includes a timer 131 , a current acquisition unit 132 , a memory 133 , a warning sign diagnostic circuit 134 , and a memory 135 .

[0099] If we focus on the semiconductor integrated circuit 1B of the second embodiment and Figure 2 The difference from the semiconductor integrated circuit 1A of the first embodiment shown is that the early-signal diagnostic unit 13B of the semiconductor integrated circuit 1B is configured to include a memory 135 directly connected to a terminal.

[0100] Memory 135 can rewrite data stored therein based on signals input from devices external to ECU 2 (e.g., manufacturing equipment). Therefore, the memory (memory 135) uses the current consumption information acquired during the manufacturing process or during factory shipment in diagnostic mode as the initial value. For example, during factory shipment testing of the semiconductor integrated circuit 1B, data on the fault current Ibreak is stored in memory 135. A pre-diagnosis threshold value calculated based on the initial value is then set in memory (memory 133).

[0101] The early warning diagnostic circuit 134 predicts the remaining life Trest_life based on the data of the fault current Ibreak stored in the memory 135. The method for predicting the remaining life Trest_life is the same as that described in the first embodiment, so its description is omitted. Furthermore, when the semiconductor integrated circuit 1B is actually used, the memories 133 and 135 can be configured as a single memory, with the respective data stored in separate storage areas.

[0102] By setting the semiconductor integrated circuit 1B to Figure 10In the configuration shown, the manufacturing equipment for ECU 2 determines the fault current Ibreak based on the initial value Iini acquired during the manufacturing process of ECU 2. The early warning diagnosis circuit 134 then uses the data on the fault current Ibreak to calculate the remaining life Trest_life and performs early warning diagnosis by comparing the remaining life Trest_life with the early warning diagnosis threshold value Tth_symptom. In this way, early warning diagnosis circuit 134 can perform early warning diagnosis for the power supply current of each semiconductor integrated circuit, taking into account manufacturing variations in ECU 2.

[0103] <Example of factory test> In the semiconductor integrated circuit 1B of the second embodiment, the manufacturing device obtains the initial value Iini of the power supply current during the factory test of the manufacturing process. Then, the manufacturing device calculates the fault current Ibreak and writes the data of the fault current Ibreak into the memory 135. Figure 11 Describe factory testing during the manufacturing process. Figure 11 This is a flowchart showing an example of a factory test of the semiconductor integrated circuit 1B.

[0104] In the manufacturing process of mounting the semiconductor integrated circuit 1B on the ECU, the ECU manufacturing apparatus starts a factory test ( S2 - 1 ) and proceeds to S2 - 2 . The processing after S2 - 2 is performed by the ECU manufacturing apparatus.

[0105] In the factory test that is usually implemented, the manufacturing device determines whether the semiconductor integrated circuit 1B is a qualified product (S2-2). When the manufacturing device determines that the semiconductor integrated circuit 1B is a qualified product ("Yes" in S2-2), the manufacturing device enters S2-3. On the other hand, when the manufacturing device determines that the semiconductor integrated circuit 1B is a defective product ("No" in S2-2), the manufacturing device enters S2-6. The semiconductor integrated circuit 1B determined to be a defective product is discarded (S2-6). Then, another semiconductor integrated circuit 1B is mounted on the ECU and the factory test (S2-1) is started again.

[0106] After the "yes" judgment in S2-2, the manufacturing device obtains the initial value Iini of the power supply current under the specified test conditions (S2-3) and enters S2-4. Next, the manufacturing device determines whether the initial value Iini of the power supply current is normal (S2-4). The judgment here is made, for example, by whether the initial value Iini of the power supply current is less than Ith_test_h and above Ith_test_l relative to the two test thresholds Ith_test_h and Ith_test_l for determining qualified products / unqualified products. (Ith_test_l≦Iini <Ith_test_h)。

[0107] If the initial value Iini of the power supply current is less than the test threshold value Ith_test_h and is above Ith_test_1, the manufacturing device determines that the initial value Iini of the power supply current is normal ("Yes" of S2-4). In this case, the manufacturing device determines that the semiconductor integrated circuit 1B is a qualified product and enters S2-5. On the other hand, if the initial value Iini of the power supply current is already above the test threshold value Ith_test_h or less than Ith_test_1, the manufacturing device determines that the initial value Iini of the power supply current is abnormal ("No" of S2-4). In this case, the manufacturing device determines that the semiconductor integrated circuit 1B is a defective product and enters S2-6.

[0108] Next, the manufacturing apparatus calculates the fault current Ibreak based on the acquired initial value Iini of the power supply current (S2-5), and proceeds to S2-7. Next, the manufacturing apparatus writes the fault current Ibreak into the memory 135 (S2-7), and proceeds to S2-8. Then, the semiconductor integrated circuit 1B is shipped as a conforming product (S2-8).

[0109] In the semiconductor integrated circuit 1B of the second embodiment described above, a fault current Ibreak is set in memory 135. This fault current Ibreak is calculated based on the initial value Iini of the power supply current acquired by the manufacturing equipment during factory testing. Therefore, the early warning diagnostic unit 13B can perform early warning diagnosis of the semiconductor integrated circuit 1B using the fault current Ibreak as a determination threshold value set to account for variations in the power supply current Ipw, which may occur in response to manufacturing variations in the ECU 2.

[0110] Furthermore, while the second embodiment describes a method for setting the fault current Ibreak in the memory 135 based on the initial value Iini acquired by the manufacturing equipment during the manufacturing process of the semiconductor integrated circuit 1B, the device that writes the fault current Ibreak may be the semiconductor integrated circuit 1B itself, rather than the manufacturing equipment. For example, the power supply current Ipw initially acquired by the current acquisition unit 132 after the ECU 2 is shipped may be set as the initial value Iini, and the fault current Ibreak corresponding to the initial value Iini may be set within the semiconductor integrated circuit 1B. This configuration eliminates the need for terminals for writing information from the manufacturing equipment to the memory 135, reducing the number of terminals in the semiconductor integrated circuit 1B. In this way, the calculation of the fault current Ibreak is not limited to the manufacturing equipment; it can also be performed within the semiconductor integrated circuit 1B.

[0111] [Third embodiment] Next, refer to Figure 12 A configuration example and an operation example of a semiconductor integrated circuit according to a third embodiment of the present invention will be described. In addition to the processing performed in the configuration of the first embodiment, the semiconductor integrated circuit of the third embodiment obtains the power supply voltage and temperature of the semiconductor integrated circuit to correct the fault current and approximate equation, thereby enabling early warning diagnosis that takes into account the current value that may fluctuate due to the influence of the power supply voltage and temperature. The following description focuses on the differences from the first embodiment.

[0112] The semiconductor integrated circuit of the third embodiment includes: a voltage acquisition unit that acquires the power supply voltage of the semiconductor integrated circuit; a temperature acquisition unit that acquires the temperature within the semiconductor integrated circuit; and a correction circuit that corrects the fault current and the approximate expression according to the power supply voltage or the temperature. Figure 12 The structure of the semiconductor integrated circuit 1C shown.

[0113] (Configuration Example of Semiconductor Integrated Circuit According to Third Embodiment) Figure 12 This is a block diagram showing an example configuration of a semiconductor integrated circuit 1C according to a third embodiment of the present invention. Here, the example configuration of the semiconductor integrated circuit 1C, the semiconductor integrated circuit 1C, the correction fault current, and the correction method for the approximate equation are described. The approximate equation to be corrected can be either equation (1) or equation (2) described above.

[0114] The semiconductor integrated circuit 1C includes a main function circuit unit 11, a main function control circuit 12, and a warning diagnostic unit 13C. The warning diagnostic unit 13C includes a voltage acquisition unit 136, a temperature acquisition unit 137, a memory 138, and a correction circuit 139 in addition to a timer 131, a current acquisition unit 132, a memory 133, and a warning diagnostic circuit 134. The voltage acquisition unit 136, the temperature acquisition unit 137, the memory 138, and the correction circuit 139 are the first embodiment (see Figure 2 ) and the semiconductor integrated circuit 1C of the third embodiment.

[0115] The voltage information acquisition unit (voltage acquisition unit 136) acquires voltage information from a voltage detection unit that detects the power supply voltage at the power supply terminal (power supply terminal 10). For example, voltage acquisition unit 136 acquires power supply voltage Vpw. The input of voltage acquisition unit 136 is connected to the power supply line, and voltage information about the power supply voltage at the time power supply current Ipw is acquired is acquired by current acquisition unit 132.

[0116] The temperature information acquisition unit (temperature acquisition unit 137) acquires temperature information from a temperature detection unit (temperature sensor) that detects the temperature inside or around the semiconductor integrated circuit (semiconductor integrated circuit 1C). The input of temperature acquisition unit 137 is connected to a terminal, which is connected to the output of a temperature detection unit (temperature sensor) located inside or outside the semiconductor integrated circuit. The temperature sensor outputs temperature information as a voltage proportional to the temperature. Temperature acquisition unit 137 acquires voltage Vtemp, which contains the temperature information output by the temperature sensor at the time the power supply current Ipw is acquired.

[0117] Memory 138 stores correction information corresponding to power supply voltage Vpw and temperature Vtemp. This correction information refers to information about the power supply current's voltage dependency and temperature dependency. By storing the power supply voltage Vpw and the voltage Vsense_pw output by current detection circuit 4 based on power supply current Ipw in a corresponding relationship in memory 138, correction circuit 139 can identify the voltage dependency of power supply current Ipw. Similarly, by storing the temperature Vtemp and voltage Vsense_pw in memory 138 in a corresponding relationship, correction circuit 139 can identify the temperature dependency of power supply current Ipw.

[0118] Correction circuit 139 corrects fault current Ibreak based on the correction information stored in memory 138 and outputs the corrected fault current Ibreak to early warning diagnosis circuit 134. Correction circuit 139 receives as input both the power supply voltage Vpw acquired by voltage acquisition unit 136 and the voltage Vtemp containing the temperature information acquired by temperature acquisition unit 137, and corrects fault current Ibreak using power supply voltage Vpw, voltage Vtemp, and the correction information stored in memory 138.

[0119] The early warning diagnosis circuit (early warning diagnosis circuit 134) uses the early warning diagnosis threshold value or current consumption corrected based on temperature information to predict the timing of failure of the circuit unit (main functional circuit unit 11). Furthermore, the early warning diagnosis circuit (early warning diagnosis circuit 134) uses the early warning diagnosis threshold value or current consumption corrected based on voltage information to predict the timing of failure of the circuit unit (main functional circuit unit 11).

[0120] (Example of operation for correcting fault current Ibreak) Here, as an example of the operation of correcting the fault current and the approximate expression in the semiconductor integrated circuit 1C, the operation of the early warning diagnosis circuit 134 correcting the fault current Ibreak based on the power supply voltage Vpw will be described.

[0121] The voltage acquisition unit 136 acquires the power supply voltage Vpw at the time when the current acquisition unit 132 acquires the power supply current Ipw. The data of the power supply voltage Vpw acquired by the voltage acquisition unit 136 is stored in the memory 138.

[0122] The temperature acquisition unit 137 acquires the temperature Vtemp at the time when the current acquisition unit 132 acquires the power supply current Ipw. The data of the temperature Vtemp acquired by the temperature acquisition unit 137 is stored in the memory 138.

[0123] The correction circuit 139 corrects the fault current Ibreak based on the power supply voltage Vpw obtained by the voltage acquisition unit 136 . Alternatively, the correction circuit 139 may correct the fault current Ibreak based on the temperature Vtemp obtained by the temperature acquisition unit 137 .

[0124] The early warning diagnosis circuit 134 calculates the remaining life Trest_life using the corrected fault current Ibreak.

[0125] Furthermore, as a method for correcting the fault current Ibreak based on the power supply voltage Vpw, for example, a method can be considered in which the power supply voltage dependency is measured during product shipment inspection and correction information corresponding to the power supply voltage is pre-stored in memory 138. The operation of correcting the early warning diagnosis based on temperature is the same as the operation of correcting the early warning diagnosis based on the power supply voltage change, and therefore, a description of the operation will be omitted.

[0126] Correction circuit 139 derives a correction value by comparing power supply voltage Vpw, which is acquired simultaneously with power supply current Ipw, with correction information corresponding to the power supply voltage stored in memory 138. Therefore, by correcting fault current Ibreak based on the power supply voltage, correction circuit 139 enables early warning diagnosis circuit 134 to perform appropriate early warning diagnosis based on the power supply voltage dependency of power supply current Ipw. For example, let's consider a case where the power supply voltage dependency, obtained during product shipment inspection, has a positive slope. If the power supply voltage at the time of acquiring power supply current Ipw is higher than expected, since power supply current Ipw is acquired at a higher value than expected, correction circuit 139 corrects fault current Ibreak so that the difference from the initial value is greater than a set value. On the other hand, if the power supply voltage at the time of acquiring power supply current Ipw is lower than expected, since power supply current Ipw is acquired at a lower value than expected, correction circuit 139 corrects fault current Ibreak so that the difference from the initial value is less than a set value.

[0127] The semiconductor integrated circuit 1C of the third embodiment described above corrects the fault current Ibreak used for early warning diagnosis based on the power supply voltage or temperature. Therefore, when the power supply current varies due to the power supply voltage or temperature, it is possible to prevent the early warning diagnosis circuit 134 from erroneously determining that the main functional circuit unit 11 is in a state indicating a failure.

[0128] Furthermore, while the third embodiment describes a method for correcting the fault current Ibreak using both power supply voltage and temperature information, the correction circuit 139 may also correct the fault current Ibreak using only the power supply voltage or temperature parameter. For example, if the early sign diagnostic unit 13C includes only the voltage acquisition unit 136, the correction circuit 139 may correct the fault current Ibreak using only the power supply voltage information. Alternatively, if the early sign diagnostic unit 13C includes only the temperature acquisition unit 137, the correction circuit 139 may correct the fault current Ibreak using only the temperature information.

[0129] [Fourth embodiment] Next, refer to Figure 13 and Figure 14 A configuration example and an operation example of a semiconductor integrated circuit according to a fourth embodiment of the present invention will be described.

[0130] In the semiconductor integrated circuit of the fourth embodiment, in addition to the processing performed in the configuration of the first embodiment, a configuration is also provided for changing the control of the semiconductor integrated circuit after a fault precursor is diagnosed in the precursor diagnosis. The semiconductor integrated circuit of the fourth embodiment makes it possible to perform desired control before an abnormality occurs in the semiconductor integrated circuit, such as safety control such as functional restriction, control of a precursor diagnosis location determined based on individual diagnosis, and the like. In addition, the following description will focus on the differences from the semiconductor integrated circuit shown in the first embodiment. In addition, the configuration of the semiconductor integrated circuit of the fourth embodiment is different from Figure 2 Since the semiconductor integrated circuit of the first embodiment shown is the same, detailed description thereof will be omitted.

[0131] <Example of Processing for Changing Driving Control After Predictive Diagnosis> Figure 13 This is a flowchart showing an example of a process for changing driving control after a warning diagnosis in a semiconductor integrated circuit according to a fourth embodiment. Figure 2 The semiconductor integrated circuit 1A shown performs the traveling control change process of the fifth embodiment.

[0132] If a warning sign is detected during the warning diagnosis, functional restrictions are implemented, such as vehicle torque control and speed limitation. A vehicle control unit (not shown) can limit vehicle speed by limiting the vehicle's torque and speed, enabling safer driving control than during normal operation of the semiconductor integrated circuit 1A. The description of processes that are identical to those described above will be omitted, and the description will focus on the differences.

[0133] Processing of S1-1 to S1-5 and Figure 3 The processing after the "No" judgment of S1-5 is the same as Figure 3 S1-6 to S1-10 shown are the same.

[0134] After a "YES" determination in S1-5, the warning diagnosis circuit 134 notifies the user of the warning sign by controlling, for example, lighting an in-vehicle warning light (S1-7), and then proceeds to S1-11.

[0135] Next, the early warning diagnosis circuit 134 determines whether the remaining life Trest_life until failure is equal to or greater than the operation determination threshold Tth_ope (S1-11). The early warning diagnosis circuit 134 determines the remaining life Trest_life by comparing the remaining life Trest_life with the operation determination threshold Tth_ope.

[0136] If the remaining life Trest_life is greater than the operation permission threshold Tth_ope ("YES" in S1-11), the early warning diagnosis circuit 134 determines that there is a margin in the remaining life Trest_life and the process proceeds to S1-12. On the other hand, if the remaining life Trest_life is less than the operation permission threshold Tth_ope ("NO" in S1-11), the early warning diagnosis circuit 134 determines that the remaining life Trest_life is short and that urgent action is required and the process proceeds to S1-9.

[0137] After the "yes" judgment in S1-11, the semiconductor integrated circuit 1A performs the conditional action (S1-12) of the fourth embodiment. The conditional action is, for example, the action of the vehicle control unit (not shown) provided in the ECU 2 to limit the torque and speed of the vehicle. After the sign diagnosis circuit (sign diagnosis circuit 134) diagnoses that there is a sign of fault, at least one of the following is performed: controlling the function of the circuit unit (main function circuit unit 11), controlling the torque of the vehicle, controlling the operation of the circuit unit (main function circuit unit 11) except for the part where the sign of fault is detected, and controlling the system including the semiconductor integrated circuit (semiconductor integrated circuit 1A) not to perform maximum operation. During the conditional action, the semiconductor integrated circuit 1A regularly monitors the power supply voltage Vpw.

[0138] Next, the semiconductor integrated circuit 1A determines whether the ignition device is off (S1-8A). Figure 3 Similar to S1-8, semiconductor integrated circuit 1A compares power supply voltage Vpw with low-voltage threshold Vmin_ope to determine whether the ignition is off. If power supply voltage Vpw is above low-voltage threshold Vmin_ope, semiconductor integrated circuit 1A determines that the ignition is not off ("No" in S1-8A), proceeds to S1-12, and continues conditional operation. On the other hand, if power supply voltage Vpw is less than low-voltage threshold Vmin_ope ("Yes" in S1-8A), semiconductor integrated circuit 1A determines that the ignition is off, stops generating load drive signals, stops normal operations such as load driving, and proceeds to S1-9.

[0139] As explained above, in Figure 13 The flowchart shown shows the process of changing driving control after a warning sign is detected during warning diagnosis. For example, the vehicle control unit may limit the vehicle's torque or rotational speed as a change in driving control. This change limits the vehicle speed. This allows for safer driving control than during normal operation of the semiconductor integrated circuit 1A.

[0140] <Incorporating Individual Diagnosis Processing into Predictive Diagnosis Processing> exist Figure 13 The fourth embodiment of the present invention describes a process for predictive diagnosis, where, when a predictive sign is present and the remaining life Trest_life is greater than or equal to the operation permission threshold Tth_ope, the vehicle is controlled to perform the minimum required operation to suppress the effects of temporal characteristic fluctuations. However, the predictive diagnosis circuit 134 may also perform an operation to identify the location for predictive diagnosis by performing an individual diagnosis capable of detecting a specific abnormality after the predictive diagnosis.

[0141] <Example of Processing of a Main Function Circuit Identified as Having a Predicted Omen After Predicted Omen Diagnosis> Figure 14 This is a flowchart showing an example of processing for determining a main function circuit having a sign after the sign diagnosis circuit 134 performs the sign diagnosis. Figure 13 The flowchart shown is an illustration of the same process as Figure 13 and Figure 14 The processing of the difference is described as the center.

[0142] After a "YES" determination in S1-5, the early warning diagnosis unit 13 notifies the vehicle user of the information indicating that the main function circuit unit 11 has a failure sign via the in-vehicle warning light or the like (S1-7), and then proceeds to S1-13.

[0143] Next, as individual diagnostics in the fourth embodiment, each function of the main function circuits 111 to 114 mounted in the main function circuit unit 11 is diagnosed (S1-13), and the process proceeds to S1-14. Furthermore, the main function circuits 111 to 114 can detect any functional abnormalities within themselves. Furthermore, the main function control circuit 12 can obtain the results of the functional diagnostics for each main function circuit 111 to 114.

[0144] Next, the main function control circuit 12 determines whether one of the main function circuits 111 to 114 has a functional abnormality based on the results of the functional diagnosis of each of the main function circuits 111 to 114 mounted in the main function circuit unit 11 (S1-14). In S1-14, the early warning diagnosis unit 13 does not perform early warning diagnosis, but instead diagnoses the presence of a functional abnormality in the main function circuits 111 to 114 by checking whether voltage abnormalities, clock abnormalities, etc. have been detected using conventional techniques.

[0145] If no functional abnormality is detected in any of the main functional circuits 111 to 114 (No in S1-14), the main functional circuit unit 11 determines that the main functional circuits 111 to 114 are not faulty and proceeds to S1-6. In S1-6, normal operation is performed.

[0146] On the other hand, if a malfunction is detected in one of the main function circuits 111 to 114 ("YES" in S1-14), there is a concern that a failure may be caused by degradation. Therefore, the main function control circuit 12 causes one of the main function circuits 111 to 114 in which the malfunction was detected to perform a conditional operation (S1-12), and then proceeds to S1-8A.

[0147] exist Figure 14 In the process shown in the flowchart, after the early warning diagnosis unit 13 performs early warning diagnosis (S1-4), the main function circuits 111 to 114 each perform individual diagnosis (S1-13) to detect specific functional abnormalities in their own circuits. Therefore, the main function control circuit 12 can determine the early warning diagnosis location based on the functional abnormality detection results of the multiple main function circuits 111 to 114.

[0148] In the semiconductor integrated circuit 1A of the fourth embodiment described above, after a warning is detected during warning diagnosis, the control of the semiconductor integrated circuit 1A including the main functional circuit in which a functional abnormality has been detected is modified. Therefore, even if a functional abnormality occurs in any of the main functional circuits 111 to 114, the main function control circuit 12 can still perform desired control of the main functional circuit unit 11, such as safety control such as functional restriction and control to determine the warning diagnosis location based on individual diagnosis.

[0149] Furthermore, since one of the main function circuits 111 to 114 that has a malfunction is functionally restricted, the temperature of the functionally restricted main function circuit can be reduced, thereby extending the remaining life of the main function circuit unit 11 including the functionally restricted main function circuit.

[0150] Furthermore, in addition to function restriction control, torque restriction, and individual diagnostic operations, the semiconductor integrated circuit 1A of the fourth embodiment can also perform control to suppress temporal fluctuations in the characteristics of the semiconductor integrated circuit 1A. Furthermore, after identifying the circuit where a sign has been detected through individual diagnostics, control can be performed to remove the portion where the sign has been detected and to prevent the vehicle control system including the ECU 2 from operating at full capacity. Furthermore, multiple types of control after a sign diagnosis can be combined.

[0151] [Fifth embodiment] Next, refer to Figure 15 An example of a premature diagnosis method for a semiconductor integrated circuit according to a fifth embodiment of the present invention will be described. In the semiconductor integrated circuit of the fifth embodiment, by dividing the main function circuit portion into several block units (for example, each main function circuit) for diagnosis, it is possible to obtain the power supply current during the operation of multiple circuits in the early warning diagnosis compared to the first embodiment. The following description focuses on the differences from the semiconductor integrated circuit shown in the first embodiment. In addition, the structure of the semiconductor integrated circuit 1A is different from Figure 2 The illustrated configuration remains unchanged, and therefore description thereof will be omitted.

[0152] As an example of the warning diagnosis process of the fifth embodiment, there is a diagnosis process that sequentially performs multiple warning diagnoses, including diagnosis A for performing diagnosis at a circuit activation rate higher than that during normal operation, and diagnosis B for performing diagnosis at a circuit activation rate that minimizes the power supply current.

[0153] (Semiconductor Integrated Circuit Diagnostic Method According to Fifth Embodiment) Figure 15 This is a flowchart showing an example of processing performed by the early warning diagnosis unit of the semiconductor integrated circuit according to the fifth embodiment of the present invention. Figure 2The semiconductor integrated circuit 1A shown in the figure performs the diagnostic method of the semiconductor integrated circuit of the fifth embodiment. In addition, the main function circuit part 11 is classified according to each function undertaken by the main function circuits 111 to 114, and the main function circuits 111 to 114 are divided into block units according to the functions. A block unit is, for example, a unit that aggregates several main function circuits. The block unit can arbitrarily change the main function circuits one by one or in groups of two. In addition, the premonition diagnosis part 13 performs premonition diagnosis of multiple modes (diagnosis A, diagnosis B) that make the operation state of the circuit part (main function circuit part 11) different in block units. In addition, the reference is omitted. Figure 4 The same processes will be described, with the differences being the focus.

[0154] (Treatment of Diagnosis A) In Diagnosis A, as described above, the circuit activation rate of the main functional circuit unit 11 is controlled to a high state (S1-41). Next, the current acquisition unit 132 simultaneously acquires the voltage Vsense_pw_A containing power supply current information from the current detection circuit 4 and the timer 131 acquires the accumulated operating time data Dt_A (S1-42A), and then proceeds to S1-43A.

[0155] Next, current acquisition unit 132 performs A / D conversion on the acquired voltage Vsense_pw_A into current data Di_A, which can be stored in memory 133 (S1-43A), and then proceeds to S1-44A. Current acquisition unit 132 and timer 131 then associate the A / D-converted power supply current data Di_A with the accumulated operating time data Dt_A, respectively, and store them in memory 133 (S1-44A). The process then proceeds to S1-47, where Diagnosis B begins.

[0156] (Treatment of Diagnosis B) In Diagnosis B, the main function control circuit 12 controls the power supply current in normal mode to the minimum circuit activation rate (S1-47) and enters S1-42B. In Diagnosis B, the number of main function circuit units operating is minimized. Therefore, in at least one of the diagnostic modes, the circuit unit (main function circuit unit 11) operates with a lower current consumption than the circuit unit (main function circuit unit 11) in normal operation.

[0157] Next, the current acquisition unit 132 acquires the voltage Vsense_pw_B having the power supply current information from the current detection circuit 4 , and simultaneously the timer 131 acquires the accumulated operation time data Dt_B ( S1 - 42B), and the process proceeds to S1 - 43B.

[0158] Next, the current acquisition unit 132 performs A / D conversion on the acquired voltage Vsense_pw_B into current data Di_B, which can be stored in the memory 133 (S1-43B), and then proceeds to S1-44B. The current acquisition unit 132 and the timer 131 then associate the A / D-converted power supply current data Di_B with the accumulated operating time data Dt_B, respectively, and store them in the memory 133 (S1-44B), before proceeding to S1-46A.

[0159] Next, the early warning diagnosis circuit 134 calculates the remaining life Trest_lifeA until reaching the fault current IBreak_A based on the time series data (Dt_colA, Di_colA) as the result of the diagnosis A stored in the memory 133 ( S1 - 46A), and proceeds to S1 - 46B.

[0160] Next, the early warning diagnosis circuit 134 calculates the remaining life Trest_lifeB until reaching the fault current IBreak_B based on the time series data (Dt_colB, Di_colB) as the result of the diagnosis B stored in the memory 133 ( S1 - 46B), and proceeds to S1 - 51 .

[0161] Next, the sign diagnosis circuit 134 determines whether there is a sign of a fault in the main function circuit unit 11 (S1-51). Here, the sign diagnosis circuit (sign diagnosis circuit 134) performs sign diagnosis based on the time series data obtained from each of the multiple diagnostic modes in the circuit unit (main function circuit unit 11) operating in multiple diagnostic modes. For example, the sign diagnosis unit 13 performs sign diagnosis by comparing the remaining life Trest_lifeA and Trest_lifeB with the sign diagnosis threshold value Tth_symptom. Then, when either the remaining life Trest_lifeA or Trest_lifeB is less than the sign diagnosis threshold value Tth_symptom, it is diagnosed as having a sign ("Yes" in S1-51), and the process goes to Figure 3 On the other hand, when both the remaining life Trest_lifeA and Trest_lifeB are equal to or greater than the sign diagnosis threshold value Tth_symptom, it is diagnosed that there is no sign (No in S1-51), and the process proceeds to S1-6.

[0162] In the semiconductor integrated circuit 1A of the fifth embodiment described above, during the prognostic diagnosis, the power supply current during the operation of multiple circuits is obtained, enabling diagnosis of the internal circuit by dividing it into several blocks. In the prognostic diagnosis of the fifth embodiment, the prognostic diagnosis unit 13 performs two prognostic diagnoses: diagnosis A and diagnosis B. Therefore, the memory 133 stores the time series data (Dt_colA, Di_colA) obtained from diagnosis A and the time series data (Dt_colB, Di_colB) obtained from diagnosis B. Furthermore, the prognostic diagnosis circuit 134 calculates the remaining lifespan Trest_lifeA and Trest_lifeB for each of the time series data for diagnosis A and diagnosis B read from the memory 133, and performs prognostic diagnosis for each block based on the respective remaining lifespans Trest_lifeA and Trest_lifeB.

[0163] Furthermore, in Diagnosis A of the fifth embodiment's predictive diagnosis, the circuit activation rate of the main functional circuit unit 11, the target of the predictive diagnosis, is increased compared to normal operation. Furthermore, as in Diagnosis B, the circuit activation rate is decreased compared to normal operation for the individual diagnosis of each of the main functional circuits 111-114. For example, in a degradation pattern where the power supply current changes slightly, if the power supply current is too large relative to the current decrease, it will be difficult to detect changes caused by temporal characteristic fluctuations. Therefore, the predictive diagnosis circuit 134 can perform a predictive diagnosis based on the power supply current at which the circuit current indicated by Diagnosis B is the minimum.

[0164] Furthermore, the predictive diagnosis circuit 134 may perform predictive diagnosis by combining the time series data obtained in diagnosis A and the time series data obtained in diagnosis B. Furthermore, in the fifth embodiment, an example of performing two predictive diagnosis processes sequentially has been described. However, in order to shorten the predictive diagnosis time, the predictive diagnosis unit 13 may also perform a process of acquiring data from one side in parallel while performing A / D conversion on the other side of the data.

[0165] Furthermore, in the fifth embodiment, a method was described in which the main functional circuits 111-114 are categorized according to their respective functions and a predictive diagnosis is performed on each of the categorized main functional circuits 111-114. However, if the sum of the activation rates of all circuits in multiple diagnoses is greater than during normal operation, the method for categorizing the diagnostic targets can be arbitrarily set. For example, there may be a diagnosis A that performs a comprehensive diagnosis of the main functional circuit unit 11 at a higher activation rate than during normal operation, and a diagnosis B that performs an individual diagnosis of one of the main functional circuits 111-114 at a lower activation rate than during normal operation. In this case, any of the main functional circuits 111-114 that are the diagnostic targets in multiple diagnoses A and B may overlap.

[0166] [Sixth embodiment] Next, refer to Figure 16 and Figure 17 An example of a configuration of a semiconductor integrated circuit and an example of a predictive diagnostic method according to a sixth embodiment of the present invention will be described. In the semiconductor integrated circuit of the sixth embodiment, premonitory diagnosis is performed at startup and individual diagnosis is performed during normal operation. This individual diagnosis allows detection of sudden abnormalities caused by occasional failures such as component detachment due to vibration. Therefore, the semiconductor integrated circuit of the sixth embodiment can detect continuous degradation caused by wear-out failures such as electromigration through premonitory diagnosis. The following description focuses on the differences from the semiconductor integrated circuit of the first embodiment.

[0167] (Configuration Example of Semiconductor Integrated Circuit According to Sixth Embodiment) Figure 16 This is a block diagram showing a configuration example of a semiconductor integrated circuit 1D according to a sixth embodiment of the present invention. Here, the configuration example of the semiconductor integrated circuit 1D and the individual diagnosis method will be described.

[0168] The semiconductor integrated circuit 1D includes a main function circuit unit 11, a main function control circuit 12, and a pre-diagnosis diagnostic unit 13D. The pre-diagnosis diagnostic unit 13D includes a timer 131, a current acquisition unit 132, a memory 133, and a pre-diagnosis diagnostic circuit 134, as well as a voltage acquisition unit 136, a temperature acquisition unit 137, and an individual diagnostic circuit 140. The voltage acquisition unit 136, the temperature acquisition unit 137, and the individual diagnostic circuit 140 are examples of the first embodiment (see Figure 2 ) and the semiconductor integrated circuit 1D of the sixth embodiment.

[0169] The configuration and operation examples of the voltage acquisition unit 136 and the temperature acquisition unit 137 are similar to those of the Figure 12 Since the functional units included in the early-sign diagnostic unit 13C of the third embodiment shown are the same, their description will be omitted. The abnormality diagnosis unit (individual diagnostic circuit 140) diagnoses abnormalities in a part of the circuit based on information obtained from the circuit unit (main function circuit unit 11). In addition, after the sign diagnosis circuit (sign diagnosis circuit 134) diagnoses that there is a sign of failure, the abnormality diagnosis unit (individual diagnostic circuit 140) diagnoses the abnormality of the circuit after the abnormality is detected. For example, the individual diagnostic circuit 140 diagnoses each function of the main function circuits 111 to 114, and outputs "abnormality" when there is a functional abnormality in one of the main function circuits. On the other hand, the individual diagnostic circuit 140 outputs "no abnormality" when there is no functional abnormality in all the main function circuits 111 to 114. In addition, in addition to detecting abnormalities in each semiconductor integrated circuit that includes a part of the circuit diagnosed as abnormal, the abnormality diagnosis unit (individual diagnostic circuit 140) can also diagnose signs of failure in the circuit unit (main function circuit unit 11) based on time series data of current consumption and accumulated operating time.

[0170] exist Figure 16 In the semiconductor integrated circuit 1D shown, the type of diagnosis varies depending on the operation of the semiconductor integrated circuit 1D. For example, the early warning diagnosis unit 13D performs early warning diagnosis during startup of the semiconductor integrated circuit 1D and performs individual diagnosis during normal operation. Therefore, the individual diagnosis circuit 140 of the early warning diagnosis unit 13D can use individual diagnosis to detect sudden abnormalities caused by, for example, occasional failures such as component loss due to vibration. Meanwhile, the early warning diagnosis circuit 134 can use early warning diagnosis to detect continuous degradation caused by wear-out failures such as electromigration.

[0171] <Examples of prognostic diagnosis and individual diagnosis> Figure 17 This is a flowchart showing an example of the process of performing the predictive diagnosis and individual diagnosis by the predictive diagnosis unit 13D of the semiconductor integrated circuit 1D according to the sixth embodiment. The semiconductor integrated circuit 1D performs the predictive diagnosis when the semiconductor integrated circuit is started up and periodically performs the individual diagnosis during normal operation. Figure 14 The description of the same processing as that described in will be given with the difference as the center.

[0172] If the semiconductor integrated circuit 1D is performing normal operation in S1-6, it then determines in S1-8 whether the ignition is off. If the power supply voltage Vpw is greater than the low voltage threshold value Vmin_ope and the semiconductor integrated circuit 1D determines that the ignition is not off ("No" in S1-8), the process proceeds to S1-13A. On the other hand, if the power supply voltage Vpw is less than the low voltage threshold value Vmin_ope and the semiconductor integrated circuit 1D determines that the ignition is off ("Yes" in S1-8), the semiconductor integrated circuit 1D stops normal operations such as load driving and proceeds to S1-9.

[0173] After the "No" determination in S1-8, the individual diagnostic circuit 140 performs functional diagnosis of the main functional circuits 111 to 114 mounted in the main functional circuit unit 11 (S1-13A), and then proceeds to S1-15.

[0174] The main function control circuit 12 receives the results of the individual diagnosis in S1-13A from the individual diagnostic circuit 140 and determines whether an abnormality is detected in the main function circuit unit 11 (S1-15). If a functional abnormality exists in any of the main function circuits 111 to 114, the main function control circuit 12 determines that an abnormality exists in the main function circuit unit 11 ("Yes" in S1-15) and proceeds to S1-9. On the other hand, if no functional abnormality exists in any of the main function circuits 111 to 114, the main function control circuit 12 determines that no abnormality exists in the main function circuit unit 11 ("No" in S1-15) and proceeds to S1-6.

[0175] In the semiconductor integrated circuit 1D of the sixth embodiment described above, the early warning diagnosis circuit 134 performs early warning diagnosis during startup of the semiconductor integrated circuit 1D, and the individual diagnosis circuit 140 performs individual diagnosis during normal operation. Therefore, the semiconductor integrated circuit 1D can detect sudden abnormalities due to occasional failures such as component detachment caused by vibration through individual diagnosis, and can detect continuous degradation due to wear-out failures such as electromigration through early warning diagnosis.

[0176] [Seventh embodiment] Next, refer to Figure 18 and Figure 19 An example of the configuration of an ECU and an example of diagnostic processing performed in each semiconductor integrated circuit according to a seventh embodiment of the present invention will be described. The ECU of the seventh embodiment includes multiple semiconductor integrated circuits and control circuits that control each semiconductor integrated circuit. Furthermore, a current detection circuit connected to a power supply line branched for each semiconductor integrated circuit outputs the power supply current as a voltage for each semiconductor integrated circuit, enabling individual early warning diagnosis for each semiconductor integrated circuit. Here, the configuration and operation of ECU 2A, which can change system control based on the priority of semiconductor integrated circuits diagnosed as having early warning signs, will be described. The following description will focus on the differences from the semiconductor integrated circuits described in the first embodiment.

[0177] (Configuration Example of Semiconductor Integrated Circuit According to Seventh Embodiment) Figure 18 This is a block diagram showing an example of the internal configuration of an ECU 2A equipped with semiconductor integrated circuits 1_1 and 1_2 according to a seventh embodiment of the present invention.

[0178] The ECU 2A includes a power supply circuit 3, a current detection circuit 4A, semiconductor integrated circuits 1_1, 1_2, drive circuits 5_1, 5_2, and a control circuit 8. The current detection circuit 4A, semiconductor integrated circuits 1_1, 1_2, drive circuits 5_1, 5_2, and control circuit 8 are the first embodiment (see Figure 1 )'s ECU2 and the ECU2A of the sixth embodiment.

[0179] The current detection circuit 4A is connected to power supply lines 21_1 and 21_2 that supply power from the power supply circuit 3 to the semiconductor integrated circuits 1_1 and 1_2. Resistor 41_1 is connected to power line 21_1 between power supply circuit 3 and semiconductor integrated circuit 1_1. Resistor 41_1 detects power supply current Ipw_1 supplied to semiconductor integrated circuit 1_1. Resistor 41_2 is connected to power line 21_2 between power supply circuit 3 and semiconductor integrated circuit 1_2. Resistor 41_2 detects power supply current Ipw_2 supplied to semiconductor integrated circuit 1_2. Resistors 41_1 and 41_2 output power supply currents Ipw_1 and Ipw_2 detected from power lines 21_1 and 21_2, respectively, as voltages to detection circuit 42.

[0180] The detection circuit 42 detects the voltages generated between the resistors 41_1 and 41_2 and outputs the voltages to the semiconductor integrated circuits 1_1 and 1_2 .

[0181] The semiconductor integrated circuits 1_1 and 1_2 are examples of circuits integrating multiple semiconductors. Figure 2 The semiconductor integrated circuit 1_1 outputs a driving instruction to the driving circuit 5_1. The driving circuit 5_1 outputs a driving instruction to the driving circuit 5_1 according to the driving instruction input from the semiconductor integrated circuit 1_1. Figure 1 The load shown is 6 ( Figure 18 The semiconductor integrated circuit 1_2 outputs a driving instruction to the driving circuit 5_2. The driving circuit 5_2 outputs a driving instruction to the driving circuit 5_2 according to the driving instruction input from the semiconductor integrated circuit 1_2. Figure 1 The load 6 shown outputs a drive signal.

[0182] Control circuit 8 controls semiconductor integrated circuits 1_1 and 1_2, respectively, based on the results of the early warning diagnosis performed by semiconductor integrated circuits 1_1 and 1_2. Control circuit 8 then performs control based on the order in which early warning diagnoses are performed on semiconductor integrated circuits 1_1 and 1_2. Furthermore, when a early warning diagnosis is performed on either semiconductor integrated circuit 1_1 or semiconductor integrated circuit 1_2, control circuit 8 performs control based on the priority order of semiconductor integrated circuits 1_1 and 1_2. Therefore, when the early warning diagnosis circuit (early warning diagnosis circuit 134) diagnoses a failure early warning, control of the system including the semiconductor integrated circuits (semiconductor integrated circuits 1_1 and 1_2) is modified.

[0183] in the case of Figure 18 In the configuration shown, the power supply currents for semiconductor integrated circuit 1_1 and semiconductor integrated circuit 1_2 are separated, enabling independent early warning diagnosis. Furthermore, control circuit 8 can change system control based on the priority of semiconductor integrated circuits 1_1 and 1_2 diagnosed as having early warning symptoms. For example, control circuit 8 can prioritize limiting functions for semiconductor integrated circuits diagnosed as having early warning symptoms, thereby reducing the load on these semiconductor integrated circuits.

[0184] <Example of Predictive Diagnosis Processing> Next, an example of the early warning diagnosis performed by the ECU 2A when the semiconductor integrated circuits 1_1 and 1_2 are responsible for control related to driving and control related to comfort, respectively, will be described. Figure 19 This is a flowchart showing an example of a predictive diagnosis performed by the ECU 2A. In addition, the description of the same process as the above-described process is omitted, and the description will be centered on the difference. Figure 19 In the description, the semiconductor integrated circuit 1_1 is sometimes referred to as a component A, and the semiconductor integrated circuit 1_2 is sometimes referred to as a component B.

[0185] The startup sequence of component A in S1-2_1 to S1-4_1 is the same as Figure 3 The processes of S1-2 to S1-4 are the same as shown. After the activation sequence of component A in S1-2_1 to S1-4_1, the early warning diagnosis section 13 (early warning diagnosis circuit 134) of the semiconductor integrated circuit 1_1 determines whether there is an early warning for component A (S1-5_1).

[0186] If the remaining lifetime Trest_life_1 of the semiconductor integrated circuit 1_1 is less than the sign diagnosis threshold value Vth_symptom_1, the sign diagnosis unit 13 of the semiconductor integrated circuit 1_1 diagnoses that a sign is present ("Yes" in S1-5_1) and proceeds to S1-9. On the other hand, if the remaining lifetime Trest_life_1 is greater than or equal to the sign diagnosis threshold value Vth_symptom_1, the sign diagnosis unit 13 of the semiconductor integrated circuit 1_1 diagnoses that there is no sign ("No" in S1-5_1) and proceeds to the activation sequence of component B from S1-2_2 to S1-4_2.

[0187] The startup sequence of components B in S1-2_2 to S1-4_2 is the same as Figure 3 After the activation sequence of component B in S1-2_2 to S1-4_2, the early warning diagnosis section 13 (early warning diagnosis circuit 134) of the semiconductor integrated circuit 1_2 determines whether there is an early warning for component B (S1-5_2).

[0188] If the remaining lifetime Trest_life_2 of the semiconductor integrated circuit 1_2 is less than the sign diagnosis threshold value Vth_symptom_2, the sign diagnosis unit 13 of the semiconductor integrated circuit 1_2 diagnoses that there is a sign of component B ("YES" in S1-5_2), and the process proceeds to S1-7. On the other hand, if the remaining lifetime Trest_life_2 is greater than or equal to the sign diagnosis threshold value Vth_symptom_2, the sign diagnosis unit 13 of the semiconductor integrated circuit 1_2 diagnoses that there is no sign ("NO" in S1-5_2), and the process proceeds to S1-6.

[0189] The ECU 2A of the seventh embodiment described above includes a plurality of semiconductor integrated circuits 1_1 and 1_2 and a control circuit 8 for controlling each of these semiconductor integrated circuits 1_1 and 1_2. By connecting a current detection circuit 4A to a power supply line branched for each semiconductor integrated circuit 1_1 and 1_2, it is possible to perform a warning diagnosis for each semiconductor integrated circuit 1_1 and 1_2. Furthermore, the control circuit 8 can change system control based on the priority of the semiconductor integrated circuits 1_1 and 1_2 diagnosed as having a warning sign.

[0190] In the seventh embodiment, a method of performing early warning diagnosis on each semiconductor integrated circuit by connecting a resistor to each power supply line of the semiconductor integrated circuit has been described. However, early warning diagnosis can also be performed collectively on multiple semiconductor integrated circuits by connecting a resistor to a power supply line shared by all semiconductor integrated circuits.

[0191] In addition, Figure 18In the figure, the ECU 2A includes two resistors 41_1 and 41_2, two semiconductor integrated circuits 1_1 and 1_2, and two drive circuits 5_1 and 5_2. However, the ECU 2A may include three or more resistors, semiconductor integrated circuits, and drive circuits.

[0192] [Eighth Embodiment] Next, refer to Figure 20 A configuration example of an ECU according to an eighth embodiment of the present invention will be described. The ECU of the eighth embodiment includes a pre-diagnosis unit that performs pre-diagnosis of the semiconductor integrated circuits based on the current consumption of multiple semiconductor integrated circuits or the current consumption of the electronic control unit. This allows pre-diagnosis of each semiconductor integrated circuit. The following description focuses on the differences between the semiconductor integrated circuits and the electronic control unit described in the first embodiment.

[0193] (Configuration Example of Electronic Control Device According to Eighth Embodiment) Figure 20 It is a block diagram showing an example of the internal configuration of the electronic control unit 2B. The electronic control device 2B includes a power supply terminal 20 , a circuit unit 11A, a control circuit 120 , and a warning diagnostic unit 13 . The circuit unit 11A includes semiconductor integrated circuits 1_1 to 1_4 as an example of a plurality of semiconductor integrated circuits. The control circuit 120 controls the operation of each semiconductor integrated circuit included in the circuit unit 11A. The early warning diagnosis unit 13 is Figure 2 The forewarning diagnostic unit 13 of the first embodiment shown in FIG. However, the forewarning diagnostic unit 13 of the first embodiment diagnoses the presence of a forewarning of failure in the main functional circuit unit 11 based on the time-series changes in the current consumption values ​​obtained from the main functional circuits 111 to 114 of the main functional circuit unit 11. On the other hand, the forewarning diagnostic unit 13 of the eighth embodiment differs in that it diagnoses the presence of a forewarning of failure in the circuit unit 11A based on the time-series changes in the current consumption values ​​obtained from the semiconductor integrated circuits 1_1 to 1_4 of the circuit unit 11A.

[0194] The current acquisition unit (current acquisition unit 132 ) acquires the current consumption of the plurality of semiconductor integrated circuits (semiconductor integrated circuits 1_1 to 1_4 ) or acquires the current consumption of the electronic control device (electronic control device 2B). The timer (timer 131 ) measures the cumulative operating time obtained by accumulating the operating time of the semiconductor integrated circuits (semiconductor integrated circuits 1_1 to 1_4 ).

[0195] The memory (memory 133) stores time series data of current consumption and accumulated operating time acquired in time series in a diagnostic mode in which the semiconductor integrated circuits (semiconductor integrated circuits 1_1 to 1_4) operate at an activation rate higher than the maximum activation rate of the semiconductor integrated circuits (semiconductor integrated circuits 1_1 to 1_4) operating normally. The early-sign diagnosis circuit (early-sign diagnosis circuit 134 ) diagnoses early-signs of failure of the semiconductor integrated circuits (semiconductor integrated circuits 1_1 to 1_4 ) based on the time-series data.

[0196] The ECU 2B of the eighth embodiment described above can diagnose a sign of failure of the circuit unit 11A including the plurality of semiconductor integrated circuits 1_1 to 1_4 based on time-series changes in the value of the current consumption acquired from the semiconductor integrated circuits 1_1 to 1_4 of the circuit unit 11A.

[0197] Furthermore, the present invention is not limited to the above-described embodiments, and various other application examples and modified examples can of course be adopted without departing from the gist of the present invention described in the claims. For example, to facilitate understanding of the present invention, the above-described embodiments describe in detail and specifically the configurations of the ECU and semiconductor integrated circuit. These embodiments are not necessarily limited to having all of the configurations described. Furthermore, portions of the configurations of the embodiments described herein may be replaced with configurations of other embodiments, and configurations of other embodiments may be added to the configurations of one embodiment. Furthermore, portions of the configurations of each embodiment may be added, deleted, or replaced with other configurations. In addition, control lines and information lines are those considered necessary for explanation, and do not necessarily represent all control lines and information lines in the product. In reality, it can be assumed that almost all components are connected to each other. Explanation of symbols

[0198] 1A…semiconductor integrated circuit, 2…ECU, 3…power supply circuit, 4…current detection circuit, 5…drive circuit, 8…control circuit, 10…power supply terminal, 11…main function circuit unit, 12…main function control circuit, 13…predictive sign diagnosis unit, 21…power supply line, 41…resistor, 42…detection circuit, 111…main function circuit, 131…timer, 132…current acquisition unit, 133…memory, 134…predictive sign diagnosis circuit

Claims

1. A semiconductor integrated circuit, characterized in that: have: a power supply terminal for supplying power from an external power source; a circuit unit including a plurality of circuits, wherein the plurality of circuits are operated at a predetermined activation rate by the power supplied from the power supply terminal; a current acquisition unit that acquires a consumption current of the power consumed by the circuit unit from the power supply terminal; a timer that measures a cumulative operation time obtained by accumulating a time during which the circuit unit operates; as well as A sign diagnosis circuit diagnoses a sign of failure of the circuit unit based on time series data of the consumption current and the accumulated operating time acquired in a time series in a diagnosis mode in which the circuit unit operates at an activation rate higher than the maximum activation rate of the circuit unit in normal operation.

2. The semiconductor integrated circuit according to claim 1, wherein The semiconductor integrated circuit includes a memory that stores time-series data of the consumption current and the accumulated operating time acquired in the diagnostic mode.

3. The semiconductor integrated circuit according to claim 2, wherein: The early warning diagnosis circuit calculates the time until the consumption current acquired in the diagnosis mode reaches a early warning diagnosis threshold value based on the time series data of the consumption current and the accumulated operation time, and predicts a failure time of the circuit unit.

4. The semiconductor integrated circuit according to claim 3, wherein: The early warning diagnosis circuit changes the early warning diagnosis threshold value according to a slope of the consumption current with respect to the accumulated operation time of the time-series data.

5. The semiconductor integrated circuit according to claim 3, wherein: The memory uses the information of the current consumption acquired in the diagnosis mode during the manufacturing process or at the time of shipment as an initial value. The early warning diagnosis threshold value calculated based on the initial value is set in the memory.

6. The semiconductor integrated circuit according to claim 3, wherein: The semiconductor integrated circuit includes a temperature information acquisition unit that acquires temperature information from a temperature detection unit that detects a temperature inside the semiconductor integrated circuit or a temperature around the semiconductor integrated circuit. The early warning diagnosis circuit predicts a failure timing of the circuit unit using the early warning diagnosis threshold value or the current consumption corrected based on the temperature information.

7. The semiconductor integrated circuit according to claim 3, wherein: The semiconductor integrated circuit includes a voltage information acquisition unit that acquires voltage information from a voltage detection unit that detects a power supply voltage of the power supply terminal. The early warning diagnosis circuit predicts a failure timing of the circuit unit using the early warning diagnosis threshold value or the current consumption corrected based on the voltage information.

8. The semiconductor integrated circuit according to claim 3, wherein: The diagnosis of a failure sign in the diagnosis mode is performed at the start-up or end of the semiconductor integrated circuit.

9. The semiconductor integrated circuit according to claim 8, wherein: After the sign of fault is diagnosed by the sign diagnosis circuit, at least one of the following controls is performed: limiting the function of the circuit unit; limiting the torque of the vehicle; causing the circuit unit to operate except for the part where the sign of fault is detected; and preventing the system including the semiconductor integrated circuit from performing maximum operation.

10. The semiconductor integrated circuit according to claim 3, wherein: The diagnostic mode includes a plurality of modes in which the operating state of the circuit unit is different. The predictive diagnosis circuit performs predictive diagnosis based on the time-series data acquired for each of the plurality of diagnostic modes from the circuit unit operating in the plurality of diagnostic modes.

11. The semiconductor integrated circuit according to claim 10, wherein: At least one of the diagnosis modes operates the circuit unit with a consumption current smaller than the consumption current consumed by the circuit unit in a normal operation.

12. The semiconductor integrated circuit according to claim 6, wherein: The semiconductor integrated circuit includes an abnormality diagnosis unit that diagnoses abnormality of a part of the circuit based on information obtained from the circuit unit. The abnormality diagnosis unit diagnoses the abnormality in the circuit after the abnormality is detected, after the early-sign diagnosis circuit diagnoses that there is a sign of failure.

13. The semiconductor integrated circuit according to claim 3, wherein: After the prediction of failure is diagnosed by the prediction diagnostic circuit, control of the semiconductor integrated circuit or a system including the semiconductor integrated circuit is changed.

14. An electronic control device composed of a semiconductor integrated circuit integrating a plurality of circuits, characterized in that: The semiconductor integrated circuit comprises: a power supply terminal for supplying power from an external power source; a circuit unit including a plurality of circuits, wherein the plurality of circuits are operated at a predetermined activation rate by the power supplied from the power supply terminal; an abnormality diagnosis unit for diagnosing an abnormality of a portion of the circuit based on information obtained from the circuit unit; a current acquisition unit that acquires a consumption current of the power consumed by the circuit unit from the power supply terminal; a timer that measures a cumulative operation time obtained by accumulating a time during which the circuit unit operates; a memory storing time series data of the current consumption and the accumulated operating time acquired in a diagnostic mode in which the circuit unit operates at an activation rate higher than a maximum activation rate of the circuit unit in a normal operation; as well as a sign diagnosis circuit for diagnosing a sign of failure of the circuit unit based on the time series data of the consumption current and the accumulated operation time acquired in time series in the diagnosis mode; Abnormality is detected for each of the semiconductor integrated circuits including a portion of the circuit diagnosed as abnormal.

15. An electronic control device comprising a plurality of semiconductor integrated circuits, characterized in that: have: a current acquisition unit configured to acquire current consumption of the plurality of semiconductor integrated circuits or current consumption of the electronic control device; a timer that measures a cumulative operation time that accumulates a time during which the semiconductor integrated circuit operates; a memory storing time series data of the current consumption and the accumulated operating time acquired in a diagnostic mode in which the circuit unit operates at an activation rate higher than a maximum activation rate of the circuit unit in a normal operation; as well as A sign diagnosis circuit diagnoses a sign of failure of the semiconductor integrated circuit based on the time series data.

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