Semiconductor diagnostic system

Abstract

The present invention achieves a low-cost semiconductor diagnostic system having a function of accurately detecting a sign of failure of a semiconductor component (20). A semiconductor diagnostic system (100) comprises: a semiconductor component (20) having a function unit (21) for outputting a diagnosis target signal (22) for diagnosing a characteristic fluctuation of a physical quantity; a reference generating unit (10) for outputting a reference signal (11) indicating a physical quantity serving as a reference for diagnosing the characteristic fluctuation; and a diagnosing unit (30) for detecting the characteristic fluctuation of the physical quantity indicated by the diagnosis target signal (22). The diagnosing unit (30) outputs a comparison result between the physical quantity indicated by the diagnosis target signal (22) and the physical quantity indicated by the reference signal (11), and the reference generating unit (10) is disposed in a location in which environmental effects are less than in the location in which the semiconductor component (20) is disposed. As a result, a sign of failure of the semiconductor component (20) can be detected accurately.

Description

Technical Field

[0001] The present invention relates to a semiconductor diagnostic system for diagnosing semiconductor components such as integrated circuits.

Background Art

[0002] In general, higher reliability is required for automotive semiconductor components than for consumer products, and each semiconductor supplier mass-produces after ensuring reliability for automotive applications. For example, guarantees may refer to 10 years of use or 200,000 kilometers of driving for a vehicle. These guarantees include the individual thinking of each automotive manufacturer and assume several hours of operating time per day for semiconductor components.

[0003] In recent years, the development of autonomous driving technology has also been active. When autonomous driving levels 4 and above are put into practical use, it is expected that operations by the driver will no longer be required, and all operations such as driving will be performed by the system installed in the vehicle.

[0004] Therefore, a technology for accurately detecting failures of semiconductor components used in the harsh environment of automobiles is desired.

[0005] Patent Document 1 describes a circuit inspection device that can accurately inspect the operating frequency of a circuit even when the operating frequency of the circuit formed in an integrated circuit is high.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] As mentioned earlier, current reliability considerations for automotive semiconductor components include the assumption of daily operating hours. This stems from the fact that humans operate the vehicles as drivers. In the future, when car sharing and fully autonomous driving become practical, it is expected that operating hours will approach 24 hours a day, especially in extreme cases such as automated delivery.

[0008] In such cases, the lifespan of semiconductor components, i.e., the time it takes for them to fail, will be considerably shorter than it is currently, and it is possible that it could be as short as one or two years.

[0009] Even current automotive semiconductor components are designed to withstand use such as the aforementioned 10-year, 200,000-kilometer driving scenario, but providing reliability guarantees for 24-hour operation as described above is not realistic in terms of both feasibility and cost.

[0010] Furthermore, in autonomous driving, a failure of a component can be fatal, so it is desirable to be able to detect failures before they occur.

[0011] The technology described in Patent Document 1 can detect when a failure occurs, but it cannot accurately detect its precursors.

[0012] Furthermore, if the technology described in Patent Document 1 were applied to the inspection of semiconductor components used in the harsh environment of automobiles, since the circuit under inspection and the equivalent circuit are located on the same integrated circuit, it is uncertain whether the equivalent circuit, which is used for comparison with the circuit under inspection, can maintain high accuracy over the long term, and therefore, high-precision fault detection cannot be expected.

[0013] Based on the above, rather than trying to guarantee the reliability of a single semiconductor component for long-term operation, a method of providing long-term guarantees that include component replacement should be considered as a future option.

[0014] Therefore, the challenge lies in developing a function that can accurately detect precursors to semiconductor component failures, and furthermore, in providing means to realize this function at a lower cost.

[0015] The objective of this invention is to realize a semiconductor diagnostic system that has the function of accurately detecting precursors to semiconductor component failures while being low-cost. [Means for solving the problem]

[0016] In view of the above issues, the semiconductor diagnostic system described in the claims of the present invention has the following configuration.

[0017] In other words, a semiconductor component having a functional unit that outputs a diagnostic signal for diagnosing characteristic fluctuations of a physical quantity in a semiconductor system, It is placed in a location with less environmental impact than the aforementioned semiconductor component. A reference generation unit that outputs a reference signal indicating a physical quantity that serves as a reference for diagnosing the aforementioned characteristic fluctuations, Display section And, equipped with, The semiconductor component further includes a diagnostic unit for detecting the characteristic fluctuations of the physical quantity indicated by the signal to be diagnosed, and a correction and storage unit. The diagnostic unit compares the physical quantity indicated by the signal to be diagnosed with the physical quantity indicated by the reference signal. The display unit Output to, The diagnostic unit further outputs the difference between the physical quantity indicated by the reference signal and the physical quantity indicated by the signal being diagnosed as a difference signal to the correction and storage unit. The correction and storage unit corrects the characteristics of the functional unit based on the difference signal and stores the cumulative correction amount. When the cumulative correction amount reaches a predetermined amount, the correction and storage unit outputs a correction limit notification to the display unit. The diagnostic unit outputs a diagnosis result to the display unit indicating that an abnormality is a precursor if the difference between the physical quantity indicated by the signal being diagnosed and the physical quantity indicated by the reference signal is greater than a predetermined value. . [Effects of the Invention]

[0018] The semiconductor diagnostic system according to the present invention provides a low-cost semiconductor diagnostic system that can accurately detect precursors to semiconductor component failures.

[0019] Furthermore, it becomes possible to accurately detect deviations from the initial characteristics of functional parts included in semiconductor components installed in vehicles, determine that a large deviation in characteristics indicates a potential failure, and issue an alarm in the form of a notification to replace the part.

[0020] Furthermore, by incorporating a mechanism to correct functional parts, the time between parts replacements can be extended, and the reduction in the number of replacements will also lead to cost reductions.

Brief Description of the Drawings

[0021] [Figure 1] It is a diagram showing an example of the configuration of the semiconductor diagnostic system 100 according to Example 1. [Figure 2] It is a diagram showing an example of the configuration of the diagnostic unit 30 according to Example 1. [Figure 3] It is a time chart for explaining the operation in which the semiconductor diagnostic system 100 detects a characteristic variation of the functional unit 21 in Example 1. [Figure 4] It is a diagram showing an example of the configuration of the semiconductor diagnostic system 100 according to Example 2. [Figure 5] It is a diagram showing an example of the configuration of the correction and storage unit 60 in Example 2. [Figure 6] It is a time chart for explaining the operation in which the semiconductor diagnostic system 100 detects and corrects a characteristic variation of the functional unit 21 in Example 2. [Figure 7] It is a diagram showing an example of the configuration of the semiconductor diagnostic system 100 according to Example 3. [Figure 8] It is a diagnostic control flowchart of the semiconductor diagnostic system 100 according to Example 3. [Figure 9] It is a diagram showing an example of the configuration of the semiconductor diagnostic system 100 according to Example 4. [Figure 10] It is a diagnostic control flowchart of the semiconductor diagnostic system 100 according to Example 4. [[ID=�4]] [Figure 11] It is a diagram showing an example of the configuration of the semiconductor diagnostic system 100 according to Example 5.

Modes for Carrying Out the Invention

[0022] Embodiments of the present invention will be described with reference to the accompanying drawings.

[0023] The following describes a semiconductor diagnostic system that can accurately detect deviations from the initial characteristics of functional components included in semiconductor parts installed in vehicles, determine that a large deviation in characteristics indicates a potential failure, and issue an alarm in the form of a notification to replace the component.

[0024] Furthermore, the semiconductor system of the present invention incorporates a mechanism for correcting functional parts, which further extends the time until component replacement is necessary and reduces costs by decreasing the number of replacements. [Examples]

[0025] (Example 1) Embodiment 1 of the present invention describes a semiconductor diagnostic system that, when the characteristics of a signal output by a functional part of a semiconductor component change over time due to external stress such as heat, detects the amount of change over time using a reference signal generated by a reference generation unit, and sets a flag if the amount of change over time is greater than or equal to a predetermined value.

[0026] Figure 1 is a block diagram showing an example of the configuration of a semiconductor diagnostic system 100 according to Embodiment 1 of the present invention. The semiconductor diagnostic system 100 according to Embodiment 1 of the present invention comprises a reference generation unit 10 that generates and outputs a reference signal 11 indicating a physical quantity that serves as a reference for diagnosis, and a semiconductor component 20. The semiconductor component 20 comprises a functional unit 21 that outputs a signal to be diagnosed 22, and a diagnostic unit 30 that compares the reference signal 11 and the signal to be diagnosed 22 for diagnosis.

[0027] The reference generation unit 10 could be, for example, a constant voltage circuit such as a bandgap reference circuit that outputs a signal consisting of a predetermined voltage value as the reference signal 11, or a constant current circuit such as a current mirror circuit that outputs a signal consisting of a predetermined current value as the reference signal 11. Alternatively, the reference generation unit 10 could also be an oscillator circuit that outputs a signal oscillating at a predetermined frequency, using one or a combination of a crystal oscillator, resistive element, inductive element, capacitive element, or a combination thereof. Furthermore, the reference generation unit 10 could be configured to incorporate one or more of the aforementioned constant voltage circuits, constant current circuits, and oscillator circuits, and select one of their outputs to output as the reference signal 11.

[0028] The functional part 21 in the semiconductor component 20 may be, for example, a power supply circuit that outputs a predetermined voltage, a constant current circuit that supplies a reference current to other functions located within the semiconductor component 20, or an oscillator circuit that generates a clock for use within the semiconductor component 20.

[0029] The diagnostic unit 30 is characterized by comparing the characteristics of the input reference signal 11 and the signal to be diagnosed 22, detecting the difference, and diagnosing a characteristic change in the semiconductor component 20 if the difference is greater than a predetermined threshold. The characteristics compared in the diagnostic unit 30 are physical quantities of the waveform, such as voltage value, current value, and frequency. The signal to be diagnosed 22 is a signal that shows the characteristics of a physical quantity.

[0030] A first power supply unit 82, which supplies power from outside the semiconductor diagnostic system 100, is connected to the reference generation unit 10. Additionally, a second power supply unit 83, which supplies power from outside the semiconductor diagnostic system 100, is connected to the semiconductor component 20.

[0031] Furthermore, the diagnostic unit 30 is connected to a display device (display unit) 84 outside the semiconductor diagnostic system 100.

[0032] Various circuits can be considered for detecting differences in characteristics, but in this embodiment 1, an example of a diagnostic unit 30 for comparing and diagnosing voltage values ​​is one that includes a subtraction circuit 40 and a comparison circuit 50, as shown in Figure 2.

[0033] In Figure 2, the simplest configuration of the subtraction circuit 40 consists of an operational amplifier 41, four resistors 42-45, and a ground potential GND. In this subtraction circuit 40, the difference in voltage values ​​between the reference signal 11 and the signal under diagnosis 22 is output as a difference signal 46 and input to the subsequent comparator 50. The comparator 50 compares the difference signal 46 with a threshold voltage Vth set as a predetermined threshold, and outputs a diagnostic result 31 based on the comparison result between the difference signal 46 and the threshold voltage Vth.

[0034] The diagnostic result 31 output by the comparator 50 is either a logical high level (hereinafter referred to as H level) or a logical low level (hereinafter referred to as L level). In Embodiment 1 of the present invention, if the voltage value of the difference signal 46 is greater than the threshold voltage Vth, the diagnostic result 31 outputs an H level; otherwise, the diagnostic result 31 outputs an L level. The diagnostic result 31 is displayed on the display device 84.

[0035] The reference generation unit 10 and the semiconductor component 20 are positioned in locations where they are not affected by heat from the surroundings, separate from the self-heating caused by the power consumption of their own electrical operation. For example, in an automobile, the semiconductor component 20 is placed inside the engine hood, and the reference generation unit 10 is placed inside the passenger compartment.

[0036] Within the engine hood, the semiconductor component 20 is exposed to a relatively higher thermal environment than when it is located inside the passenger compartment, due to heat generated by the operation of the engine and other internal combustion engine components in the case of an internal combustion engine vehicle, and due to heat generated by the operation of the vehicle drive inverter system and other components in the case of an electric vehicle.

[0037] On the other hand, considering that the interior of a vehicle, which was given as an example of where the reference generation unit 10 is located, is generally set up with the assumption that occupants will be riding in it, and therefore, in most cases, temperature control equipment such as air conditioning is installed for comfort, it can be assumed that the temperature inside the vehicle is relatively lower than that in the engine compartment.

[0038] Furthermore, semiconductor components 20 generally have mechanisms for performing functional operations in addition to the functional unit 21, and these functions generate heat, resulting in a higher internal temperature for the semiconductor component 20 in relation to the ambient temperature. On the other hand, the reference generation unit 10 does not necessarily need to incorporate other functions, and can be designed to generate less heat relative to the semiconductor component 20.

[0039] From the above, it can be seen that in this embodiment 1, the reference generation unit 10 is less affected by heat from the surroundings than the semiconductor component 20. In other words, the amount of change over time in the physical quantity of the reference signal 11 is relatively small compared to the amount of change over time in the physical quantity indicated by the signal under diagnosis 22. The operation of the semiconductor diagnostic system 100 in this embodiment 1 in detecting the characteristic change of the functional unit 21 will be explained with reference to Figure 3.

[0040] Figure 3(a) schematically shows the temporal variation of the characteristics (voltage values ​​in this embodiment 1) of the reference signal 11 (shown as a dashed line) and the signal under diagnosis 22 (shown as a solid line).

[0041] In the semiconductor diagnostic system 100 of this embodiment 1, the characteristics of the reference signal 11 and the voltage value of the signal under diagnosis 22 at time t0 are assumed to represent the initial characteristic values. As mentioned above, in this embodiment 1, the semiconductor component 20 and the functional unit 21 and the reference generation unit 10 are located in places with different thermal influences, with the semiconductor component 20 being located in a place where the temperature is higher.

[0042] It is generally known that semiconductor elements and semiconductor integrated circuits using them experience irreversible changes in their properties due to chemical reactions within the integrated circuit, depending on the operating time under higher temperature conditions.

[0043] Figure 3(b) shows the detected values ​​of the difference signal 46 over time. The difference signal 46 outputs the difference between the characteristics of the reference signal 11 and the characteristics of the signal under diagnosis 22. At time t1, when the voltage value indicated by the difference signal 46 becomes equal to or exceeds the threshold Vth set by the comparator 50, the output of the diagnostic result 31 changes from L level to H level, as shown in Figure 3(c).

[0044] Although not specifically shown in this embodiment 1, if a mechanism is provided to detect when the diagnostic result 31 changes to an H level using any system within the vehicle, the vehicle user or others can be notified that the semiconductor component 20 needs to be replaced.

[0045] In this embodiment 1, it was assumed that the reference generation unit 10 and the semiconductor component 20 were placed in locations with different thermal influences. However, different arrangements may also be considered for the voltage applied and the humidity of the location where the semiconductor is used, as these are factors that cause variations in semiconductor characteristics.

[0046] The example of the diagnostic unit 30 described above is merely one example written from the perspective of comparing voltage values, and it should be noted that similar difference detection functions can be realized in a variety of other forms. For example, it could be a current-input type comparator circuit for comparing current values, or a digital counter or phase comparator circuit for comparing frequencies.

[0047] Furthermore, the comparison may be performed using analog values ​​within the diagnostic unit 30 or during the preceding comparison input, or it may be performed after converting to digital values.

[0048] In this embodiment 1, the characteristic variation determination value, referred to as the threshold voltage Vth, can be set by assuming the variation rate or absolute value based on the initial characteristics. However, in the case of a constant voltage source like this embodiment 1, the power supply voltage requirements are also defined for the components to which the voltage is supplied, and it is also possible to determine the value from these requirements.

[0049] The characteristic fluctuation determination value may be output by an electronic circuit predetermined to show a specific value within the diagnostic unit 30, or it may be output by a storage element such as a register or memory that has a mechanism for writing numerical information.

[0050] From the above, the operation of the semiconductor diagnostic system 100, characterized in that the reference generation unit 10 is located in a different location from the semiconductor component 20 having the functional unit 21, and the characteristic changes over time are smaller in the reference generation unit 10 than in the functional unit 21 that is being diagnosed, has been clarified.

[0051] According to Embodiment 1 of the present invention, a semiconductor diagnostic system 100 can be realized that has the function of accurately detecting precursors to failure of semiconductor components 20, while also being low cost.

[0052] In Embodiment 1 of the present invention, fault diagnosis may be configured to obtain a diagnosis result not from a single diagnosis, but from multiple diagnoses. For example, if three consecutive diagnoses indicate the presence of a precursor to a fault, it may be determined that there is a precursor to a fault. This is to take into account the possibility of noise generation during diagnosis.

[0053] (Example 2) Next, Example 2 of the present invention will be described.

[0054] In Embodiment 2 of the present invention, a semiconductor diagnostic system 100 is described which, when the characteristics of the signal output by the functional unit 21 of a semiconductor component 20 change over time due to external stress such as heat, detects the amount of change over time using a reference signal generated by a reference generation unit 10, corrects the characteristics of the functional unit 21 based on the amount of change over time, and further performs an operation to set a flag when the amount of change over time exceeds a predetermined value.

[0055] The following will explain the differences from Embodiment 1 of the present invention, omitting any overlapping parts. The first power supply unit 82, the second power supply unit 83, and the display device 84 shown in Figure 1 are not shown. Also, similar to Embodiment 1 of the present invention, in Embodiment 2, the reference generation unit 10 is assumed to be less affected by heat from the surroundings than the semiconductor component 20.

[0056] Figure 4 is a block diagram showing an example of the configuration of a semiconductor diagnostic system 100 according to Embodiment 2 of the present invention. Focusing on the differences from Embodiment 1 of the present invention, the semiconductor diagnostic system 100 further includes a correction and storage unit 60 that corrects the characteristics of the functional unit 21 based on the difference signal 46 detected by the diagnostic unit 30, and stores the corrected amount of the functional unit 21.

[0057] The correction and storage unit 60 corrects the characteristics of the functional unit 21 based on the difference signal 46 and stores the cumulative correction amount. When the cumulative correction amount reaches a predetermined amount, it outputs a correction limit notification.

[0058] Figure 5 shows an example of the configuration of the correction and storage unit 60. The correction and storage unit 60 in this embodiment 2 includes a correction amount calculation unit 63 that outputs a correction amount instruction signal 61 based on the difference signal 46 and the previously corrected amount 66, a previously corrected amount storage unit 64 that stores the information as a new previously corrected amount when the correction amount instruction signal 61 is changed, and a correction limit determination unit 65 that determines whether the value indicated by the correction amount instruction signal 61 is within the range correctable by the function unit 21, and outputs an H level to the correction limit notification 62 if it exceeds the correctable limit, and an L level otherwise.

[0059] The operation by which the semiconductor diagnostic system 100 in this embodiment 2 detects characteristic fluctuations of the functional unit 21 and corrects the characteristics of the functional unit 21 will be explained using Figures 6(a) to (d).

[0060] (a) of FIG. 6 schematically shows the temporal variation of the characteristics of the reference signal 11 and the signal 22 to be diagnosed (voltage value in the second embodiment). In the semiconductor diagnostic system 100 of the second embodiment, it is assumed that the characteristics of the reference signal 11 and the voltage value of the signal 22 to be diagnosed show initial characteristic values at a certain time t0. In the second embodiment, the semiconductor component 20, the functional unit 21, and the reference generation unit 10 are arranged at locations with different thermal effects, and it is assumed that the semiconductor component 20 is arranged at a location with a higher temperature.

[0061] (b) of FIG. 6 shows the detected value of the differential signal 46 over time. Also, (c) of FIG. 6 shows the value of the correction amount instruction signal 61 for correcting the characteristics of the functional unit 21. The differential signal 46 outputs the difference value between the characteristics of the reference signal 11 and the signal 22 to be diagnosed. In the semiconductor diagnostic system 100 of the second embodiment, the characteristics of the reference signal 11 and the voltage value of the signal 22 to be diagnosed at time t0 show initial characteristic values, the characteristics of the functional unit 21 are not corrected, and the already corrected amount 66 is zero. Times t2, t3, and t4 show an example of the times when the diagnostic unit 30 performs diagnosis of characteristic variations.

[0062] At time t2, if, as a result of the characteristic variation diagnosis by the diagnostic unit 30, the voltage value indicated by the differential signal 46 is Vc1 (<Vth), then at this point, the value Vc1 of the differential signal 46 is input to the correction and storage unit 60. As described above, the already corrected amount 66 is zero at time t0, and at time t2, the correction amount instruction signal 61 for time t2 and subsequent times is calculated from the differential signal 46 and the already corrected amount 66 by the correction amount calculation unit 63.

[0063] In the second embodiment, at time t2, the correction amount instruction signal 61 is updated from 0 to Vc1. Based on the value of the updated correction amount instruction signal 6, the functional unit 21 corrects its characteristics, and as shown at time t2 in (a) of FIG. 6, the characteristics of the signal 22 to be diagnosed align with the characteristics of the reference signal 11.

[0064] Next, assuming that as a result of the characteristic variation diagnosis by the diagnosis unit 30 at time t3, the voltage value indicated by the differential signal 46 is Vc2 (< Vth), the value Vc2 of the differential signal 46 at this time is input to the correction and storage unit 60. The already corrected amount 66 was updated to Vc1 at time t2, and at time t3, the correction amount instruction signal 61 for time t2 and later is calculated from the differential signal 46 and the already corrected amount 66 by the correction amount calculation unit 63.

[0065] In this Example 2, at time t3, the correction amount instruction signal 61 is updated from 0 to Vc1 + Vc2. Based on the value of the updated correction amount instruction signal 61, the characteristics of the functional unit 21 are corrected, and as shown at time t3 in (a) of FIG. 6, the characteristics of the diagnosed signal 22 are aligned with the characteristics of the reference signal 11.

[0066] In this Example 2, assume that when the already corrected amount 66 is updated to Vc1 + Vc2 at time t3, the upper limit that can be corrected by the functional unit 21, that is, the correction limit, is reached.

[0067] Generally, in the correction of characteristics, an analog method using voltage input or a digital method using bus signal input is used. The correction limit is determined by the range where voltage can be input in the case of the analog method, and the range that can be represented by a binary number according to the number of bits of the bus signal in the case of the digital method. The correction limit determination unit 65 detects the correction limit from the above-mentioned analog voltage input or the binary representation of the bus signal, and outputs a high level to the correction limit notification 62 as shown in (d) of FIG. 6.

[0068] Furthermore, consider the case where the characteristic variation diagnosis by the diagnosis unit 30 is performed at time t4. At this time, the correction range of the functional unit 21 has reached the upper limit, and even if the differential signal 46 takes a positive value other than 0, no further correction is performed. Also, at time t4, the differential signal is less than Vth, and as shown in (d) of FIG. 6, the diagnosis result 31 of the characteristic variation outputs a low level.

[0069] When the value of the difference signal 46 reaches Vth at time t5, the diagnostic unit 30 diagnoses that the functional unit 21 has a characteristic change, and an H level is output to the diagnostic result 31, as shown in Figure 6(d). Similar to Embodiment 1, if a mechanism is provided to detect the change in the diagnostic result 31 to an H level using one of the in-vehicle systems, such as the display device 84 shown in Figure 1, the vehicle user can be notified that the semiconductor component 20 needs to be replaced. Furthermore, the correction limit notification 62, which outputs an H level at time t3, can be used as an even more predictive notification to the user, in addition to the replacement notification triggered by the output of an H level in the diagnostic result 31.

[0070] Assuming that the characteristic changes of the functional unit 21 proceed at the same speed in both Example 1 and this embodiment (Example 2), it is easy to imagine that the time t1 at which an H level is output to the diagnostic result 31 of the functional unit 21 in Example 1 is later than the time t5 at which an H level is output to the diagnostic result 31 of the functional unit 21 in this embodiment 2.

[0071] In other words, this embodiment 2 provides the same effects as embodiment 1, but the semiconductor components 20 and functional units 21 in the semiconductor diagnostic system 100 can be used for a longer period compared to embodiment 1, which has the effect of allowing for a longer interval between parts replacements, for example, in automobiles. From the above, the operation of the semiconductor diagnostic system 100, which is characterized by smaller temporal characteristic fluctuations than the functional unit 21 being diagnosed, has been clarified by arranging the reference generation unit 10 in a location with different thermal influences.

[0072] (Example 3) Next, Example 3 of the present invention will be described.

[0073] In Embodiment 3 of the present invention, the operation of a semiconductor diagnostic system 100 that enables the diagnosis of characteristic fluctuations while reducing the number of components and suppressing cost increases by sharing one reference generation unit 10 among multiple semiconductor components 20-1 to 20-n will be described.

[0074] Figure 7 is a block diagram showing an example of the configuration of a semiconductor diagnostic system 100 according to Embodiment 3 of the present invention. The first power supply unit 82, the second power supply unit 83, and the display device 84 are not shown. Focusing on the differences from Embodiment 2 of the present invention, the semiconductor diagnostic system 100 further includes a plurality of semiconductor components 20-1 to 20-n (where n is an integer of 2 or more) and a diagnostic control unit 70 that outputs a diagnostic control signal 71 for selectively specifying one of the semiconductor components 20-1 to 20-n to be the target of diagnosis and selectively performing a diagnostic operation.

[0075] Furthermore, the input selection unit 80 selectively outputs the reference signal 11 to one of the multiple semiconductor components 20-1 to 20-n according to the diagnostic control signal 71 from the diagnostic control unit 70, and selects one each from the diagnostic results 31-1 to 31-n and correction upper limit notifications 62-1 to 62-n output from the multiple semiconductor components 20-1 to 20-n and outputs them to the diagnostic control unit 70. It is equipped with an output selection unit 90.

[0076] The diagnostic operations performed on the selected semiconductor components are the same as those described in Example 2. In Example 3, the control content of the diagnostic control unit 70 for multiple semiconductor components will be explained using the flowchart in Figure 8.

[0077] After the flow starts at step S10 in the flowchart of Figure 8, first, in step S100, a variable for selecting one of the multiple semiconductor components 20-1 to 20-n is diagnosed. This is set in the control unit 70. In this embodiment 3, the variable k is used to select the k-th semiconductor component 20-k.

[0078] In step S110, the input selection unit 80 and the output selection unit 90 are configured based on the settings of variable k. Specifically, the reference signal 11, diagnostic result 31, and correction limit notification 62 are controlled to be input and output to the k-th semiconductor component 20-k, so that they are connected to the reference signal 11-k, diagnostic result 31-k, and correction limit notification 62-k, respectively.

[0079] The flow from step S120 to step S150 is the same as what was described in Example 2, but applied to the k-th semiconductor component 20-k and the functional unit 21. Love. The results obtained by completing the flow up to step S150 are the diagnostic result 31 and the correction limit notification 62, and in step S160 the diagnostic control unit 70 receives these signals and stores whether each signal is at an H level or an L level.

[0080] In step S170, it is determined whether the characteristic variation diagnosis for the nth semiconductor component 20-n has been completed. If yes, the process proceeds to step S20 to complete the flow. If no, the process proceeds to step S180, k is incremented, and then the process proceeds back to step S110.

[0081] According to this embodiment 3, characteristic variations can be diagnosed for multiple semiconductor components 20-1 to 20-n in the same manner as in embodiment 2, and a semiconductor diagnostic system 100 can be realized that can diagnose characteristic variations while reducing the number of components and suppressing cost increases.

[0082] The above explanation demonstrates the operation of a semiconductor diagnostic system 100 that enables the diagnosis of characteristic fluctuations while reducing the number of components and suppressing cost increases by sharing one reference generation unit 10 among multiple semiconductor components 20-1 to 20-n.

[0083] (Example 4) Next, Example 4 of the present invention will be described.

[0084] In Embodiment 4 of the present invention, the diagnostic unit 30, which was mounted on each of the multiple semiconductor components 20-1 to 20-n in Embodiment 3, is placed outside of the semiconductor components 20-1 to 20-n and shared, thereby reducing variations and component costs, and enabling the diagnosis of characteristic fluctuations. The operation of this semiconductor diagnostic system 100 will be described.

[0085] In the example block diagram of the diagnostic unit 30 shown in this embodiment 1, the subtraction circuit 40 is shown as an operational amplifier 41 and resistor elements 42-45. When these are mounted for each semiconductor component 20-1 to 20-n, the diagnostic accuracy of the diagnostic unit 30 will vary for each semiconductor component 20-1 to 20-n due to the input offset voltage of the operational amplifier 41 during semiconductor component manufacturing and the accuracy variations of the resistor elements 42-45.

[0086] In Example 4, the diagnostic unit 30 is placed outside and shared with the semiconductor components 20-1 to 20-n, with the aim of performing characteristic diagnosis while eliminating variations in diagnostic accuracy.

[0087] Figure 9 is a block diagram showing an example of the configuration of a semiconductor diagnostic system 100 according to Embodiment 4 of the present invention. The first power supply unit 82, the second power supply unit 83, and the display device 84 are not shown. Focusing on the difference between Embodiment 3 and Embodiment 4 of the present invention, in Embodiment 3, the diagnostic unit 30, which was provided in each of the multiple semiconductor components 20-1 to 20-n, is placed outside of the semiconductor components 20-1 to 20-n.

[0088] Furthermore, the reference signal 11 is directly input to the diagnostic unit 30, and the diagnostic signal selection unit 81 selects one of the multiple semiconductor components 20-1 to 20-n to input the diagnostic signal 22-1 to 22-n to the diagnostic unit 30, and the differential signal 46 calculated by the diagnostic unit 30 is selectively input to the multiple semiconductor components 20-1 to 20-n, and one correction upper limit notification 62-1 to 62-n is selected from each of the multiple semiconductor components 20-1 to 20-n and output to the diagnostic control unit 70. It includes an output selection unit 91 for this purpose.

[0089] In the following, the control details of the diagnostic control unit 70 for multiple semiconductor components 20-1 to 20-n in Example 4 will be explained using the flowchart in Figure 10.

[0090] After the flow starts at step S10 in the flowchart of Figure 10, first in step S200, a variable is used to select one of the multiple semiconductor components 20-1 to 20-n for diagnosis. This is set in the control unit 70.

[0091] In step S210, the settings of the diagnostic signal selection unit 81 and the output selection unit 91 are made based on the settings of the variable k. Specifically, the diagnostic signal 22, the difference signal 46, and the correction limit notification 62 are controlled to be input and output to the k-th semiconductor component 20-k, so that they are connected to the diagnostic signal 22-k, the difference signal 46-k, and the correction limit notification 62-k, respectively.

[0092] The flow from step S220 to step S250 is the same as described in Example 3, so the explanation will be omitted. The results obtained by completing the flow up to step S250 are the diagnostic result 31 and the correction limit notification 62. In step S260, the diagnostic control unit 70 receives these signals and stores whether each signal is at an H level or an L level.

[0093] In step S270, it is determined whether the characteristic variation diagnosis for the nth semiconductor component 20-n has been completed. If Yes, the process proceeds to step S20 to complete the flow. If No in step S270, the process proceeds to step S280, k is incremented, and then the process proceeds to step S210 again.

[0094] According to this embodiment 4, since the diagnostic unit 30 is placed outside and shared with the semiconductor components 20-1 to 20-n, the same effects as in embodiment 3 can be obtained, and a semiconductor diagnostic system 100 that can diagnose characteristic fluctuations while reducing variations and component costs can be realized.

[0095] The above explanation demonstrates the operation of a semiconductor diagnostic system 100 that enables the diagnosis of characteristic variations while reducing variability and component costs by locating and sharing the diagnostic unit 30 outside of the semiconductor component.

[0096] (Example 5) Next, Example 5 of the present invention will be described.

[0097] Embodiment 5 of the present invention describes a semiconductor diagnostic system 100 in which the reference generation unit 10 is located outside the vehicle and the semiconductor components 20 are located inside the vehicle.

[0098] Figure 11 is a block diagram showing an example of the configuration of a semiconductor diagnostic system 100 according to Embodiment 5 of the present invention. The first power supply unit 82, the second power supply unit 83, and the display device 84 are not shown. Figure 11 is based on Figure 4, which shows an example of the configuration of a semiconductor diagnostic system 100 in Embodiment 2.

[0099] In Example 2, similar to Example 1, the reference generation unit 10 was positioned in a location with different thermal influence from the semiconductor component 20. However, in Example 5, the reference generation unit 10 is positioned in an external device or external equipment 200, while the semiconductor component 20 is positioned in the vehicle 300.

[0100] There are various examples of external devices or external equipment 200, one example being charging equipment for electric vehicles and plug-in hybrid vehicles. The advantages of placing the reference generation unit 10 in the charging equipment are that it reduces the effects of heat compared to placing it on the vehicle 300, and furthermore, if the charging equipment is equipped with a correction function for the reference generation unit 10, it is possible to always output a reference signal 11 that exhibits the desired characteristics.

[0101] Furthermore, since charging an electric vehicle is an operation that may occur in conjunction with the operation of the vehicle 300, if characteristic fluctuation diagnosis is performed during charging, it will also be possible to perform periodic diagnosis during charging.

[0102] A charging cable is preferred as a means of supplying the reference signal 11 to the semiconductor component 20.

[0103] As another example, the reference generation unit 10 can be installed in refueling facilities for gasoline, liquefied natural gas, hydrogen, etc., making it possible for the vehicle driver to perform characteristic change diagnosis at the same time as the refueling operation.

[0104] Furthermore, another example involves integrating the reference generation unit 10 into a vehicle diagnostic device. When the vehicle diagnostic device is connected to the vehicle 300 to check for the presence of data accumulated in the electronic control unit during a statutory inspection of the vehicle 300, a characteristic variation diagnosis of the semiconductor component 20 can be performed, thereby enabling periodic characteristic variation diagnosis of the semiconductor component 20 and the functional unit 21.

[0105] The above description refers to the arrangement of the reference generation unit 10, and characteristic variation diagnosis can be performed using the methods described in Examples 1 to 4.

[0106] According to this embodiment 5, the reference generation unit 10 is placed on an external device or external equipment 200, and the semiconductor component 20 is placed on the vehicle. This provides the same effects as in embodiment 2, but also reduces the effects of heat compared to placing the reference generation unit 10 on the vehicle 300. Furthermore, by providing a correction function for the reference generation unit 10 in the external device or external equipment 200, a reference signal 11 exhibiting desired characteristics can be output when the external device or external equipment 200 is in use, making it possible to detect precursors to failure of the semiconductor component 20.

[0107] The above describes the semiconductor diagnostic system 100, particularly when the reference generation unit 10 is located outside the vehicle.

[0108] In addition, in the semiconductor diagnostic systems of the above-described embodiments 1 to 4, the semiconductor components 20 can be configured to be located outside the vehicle's passenger compartment, while the reference generation unit 10 can be located inside the passenger compartment.

[0109] Furthermore, in the example described above, the semiconductor component 20 and the reference generation unit 10 are located in places with different thermal influences. However, other examples also include cases where the semiconductor component 20 and the reference generation unit 10 are located in places with different humidity influences. Thermal influences and humidity influences can be collectively referred to as environmental influences.

[0110] Furthermore, the following examples illustrate other embodiments of the present invention. The semiconductor system includes a semiconductor component 20 having a functional unit 21 that outputs a diagnostic signal 22 for diagnosing characteristic fluctuations of a physical quantity, a reference generation unit 10 that outputs a reference signal 11 indicating a reference physical quantity for diagnosing characteristic fluctuations, a diagnostic unit 30 for detecting the characteristic fluctuations of the physical quantity indicated by the diagnostic signal 22, a first power supply unit 82 that supplies power to the reference generation unit 10, and a second power supply unit 83 that supplies power to the semiconductor component 20. The diagnostic unit 30 outputs a comparison result between the physical quantity indicated by the diagnostic signal 22 and the physical quantity indicated by the reference signal 11, and the first power supply unit 82 is located in a place with less environmental impact than the second power supply unit 83. [Explanation of Symbols]

[0111] 100...Semiconductor diagnostic system, 10...Reference generation unit, 11...Reference signal, 20, 20-1~20-n...Semiconductor components, 21...Functional unit, 22...Signal under diagnosis, 30...Diagnostic unit, 31, 31-1~31-n...Diagnostic results, 40...Subtraction circuit, 41...Operational amplifier, 42~45...Resistor elements, 46...Differential output, GND...Ground potential, 50...Comparator, Vth...Characteristic variation diagnostic threshold, 60...Correction and storage 61... Correction amount instruction signal, 62... Correction limit notification, 63... Correction amount calculation unit, 64... Previously corrected amount storage unit, 65... Correction limit determination unit, 66... ​​Previously corrected amount, 70... Diagnostic control unit, 71... Diagnostic control signal, 80... Input selection unit, 81... Diagnosed signal selection unit, 82... First power supply unit, 83... Second power supply unit, 84... Display device, 90, 91... Output selection unit, 200... External device or equipment, 300... Vehicle

Claims

1. A semiconductor component having a functional unit that outputs a diagnostic signal for diagnosing characteristic fluctuations of a physical quantity, A reference generation unit is located in a place with less environmental impact than the aforementioned semiconductor component and outputs a reference signal that indicates a physical quantity that serves as a reference for diagnosing the characteristic variation. Display unit and Equipped with, The aforementioned semiconductor component further, The system includes a diagnostic unit for detecting the characteristic fluctuations of the physical quantity indicated by the signal to be diagnosed, and a correction and storage unit. The diagnostic unit outputs to the display unit the result of comparing the physical quantity indicated by the signal to be diagnosed with the physical quantity indicated by the reference signal. The diagnostic unit further outputs the difference between the physical quantity indicated by the reference signal and the physical quantity indicated by the signal to be diagnosed as a difference signal to the correction and storage unit. The correction and storage unit corrects the characteristics of the functional unit based on the difference signal and stores the cumulative correction amount. The correction and storage unit outputs a correction limit notification to the display unit when the cumulative correction amount reaches a predetermined amount. The semiconductor diagnostic system is characterized in that the diagnostic unit outputs a diagnostic result to the display unit indicating that an abnormality is a precursor when the difference between the physical quantity indicated by the signal to be diagnosed and the physical quantity indicated by the reference signal is greater than a predetermined value.

2. In the semiconductor diagnostic system according to claim 1, A semiconductor diagnostic system characterized in that the amount of change over time of the physical quantity of the reference signal is relatively smaller than the amount of change over time of the physical quantity indicated by the signal to be diagnosed.

3. In the semiconductor diagnostic system according to claim 1, The semiconductor component comprises multiple such components, A semiconductor diagnostic system characterized by comprising a diagnostic control unit that outputs a diagnostic control signal that specifies one of the semiconductor components to be diagnosed from among a plurality of semiconductor components.

4. In the semiconductor diagnostic system according to claim 3, An input selection unit outputs the reference signal output from the reference generation unit to one of the semiconductor components to be diagnosed among the plurality of semiconductor components, in accordance with the diagnostic control signal output from the diagnostic control unit. An output selection unit that selects one of multiple diagnostic results output from multiple semiconductor components and outputs it to the diagnostic control unit, A semiconductor diagnostic system characterized by comprising the following features.

5. In the semiconductor diagnostic system according to claim 3, A diagnostic signal selection unit selects one of the multiple semiconductor components to be diagnosed according to the diagnostic control signal output from the diagnostic control unit and outputs the diagnostic signal to the diagnostic unit, An output selection unit outputs the difference signal output from the diagnostic unit to the correction and storage unit of one selected semiconductor component from among the plurality of semiconductor components, and outputs a correction limit notification output from the correction and storage unit of one selected semiconductor component from among the plurality of semiconductor components to the diagnostic control unit. Equipped with, A semiconductor diagnostic system characterized in that the diagnostic unit is shared by a plurality of semiconductor components, and the diagnostic results are output from the diagnostic unit to the diagnostic control unit.

6. In the semiconductor diagnostic system according to claim 1, A semiconductor diagnostic system for a vehicle, characterized in that the semiconductor component is located outside the vehicle's passenger compartment, and the reference generation unit is located inside the passenger compartment.

7. In the semiconductor diagnostic system according to claim 1, A semiconductor diagnostic system for a vehicle, characterized in that the reference generation unit is located outside the vehicle and the semiconductor components are located inside the vehicle.

8. In the semiconductor diagnostic system according to claim 1, A semiconductor diagnostic system characterized in that the aforementioned environmental impact is a thermal impact.

9. In the semiconductor diagnostic system according to claim 1, A semiconductor diagnostic system characterized in that the aforementioned environmental impact is the effect of humidity.

Images