Device, semiconductor device, gate driver, and power module

Abstract

To provide a device, a semiconductor apparatus, a gate driver and a power module.SOLUTION: A device comprises series circuits 110x, 110y, 110z in which rectifiers 120x, 120y, 120z and fuse elements 130x, 130y, 130z are connected in series with each other. One end on an anode side of the rectifier in the series circuit is connected with a first connection point P1a having a reference potential, and the other end on a cathode side of the rectifier in the series circuit is connected with a second connection point P2a having a higher potential than the reference potential. The device includes a parallel circuit in which the plurality of series circuits is connected in parallel with each other. A rectification property of the rectifier in at least one series circuit connected in parallel may be different from the rectification property of the rectifier in the other series circuit connected in parallel.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a device, a semiconductor device, a gate driver, and a power module. [Background technology]

[0002] Patent Document 1 states that "an ESD protection circuit for a fuse element in a semiconductor device is realized." [Prior art document] [Patent documents] [Patent Document 1] JP 2014-204602 A Summary of the Invention

[0003] In a first aspect of the present invention, there is provided a device, which may include a series circuit in which a rectifying element and a fuse element are connected in series, wherein one end on the anode side of the rectifying element in the series circuit may be connected to a first connection point having a reference potential, and the other end on the cathode side of the rectifying element in the series circuit may be connected to a second connection point having a potential higher than the reference potential.

[0004] The device may further include a parallel circuit in which a plurality of the series circuits are connected in parallel.

[0005] The rectifying characteristics of the rectifying elements in at least one of the series circuits connected in parallel may be different from the rectifying characteristics of the rectifying elements in the other series circuits connected in parallel.

[0006] The rectifying element may have a PN junction, and a junction area of ​​the PN junction in the at least one series circuit may be different from a junction area of ​​the PN junction in the other series circuit.

[0007] The fusing characteristics of the fuse elements in the at least one series circuit may be the same as the fusing characteristics of the fuse elements in the other series circuits.

[0008] The fuse elements in at least one of the series circuits connected in parallel may have melting characteristics different from the fuse elements in the other series circuits connected in parallel.

[0009] The rectifying characteristics of the rectifying elements in the at least one series circuit may be the same as the rectifying characteristics of the rectifying elements in the other series circuits.

[0010] In a second aspect of the present invention, there is provided a device. The device may include a parallel circuit in which a plurality of series circuits are connected in parallel, each of which has a resistive element and a fuse element connected in series and which have different times until the fuse element melts due to an overcurrent. One end of the parallel circuit may be connected to a first connection point having a reference potential, and the other end of the parallel circuit may be connected to a second connection point having a potential higher than the reference potential.

[0011] The electrical resistance of the resistive element in at least one of the series circuits connected in parallel may be different from the electrical resistance of the resistive element in the other series circuits connected in parallel.

[0012] The fusing characteristics of the fuse elements in the at least one series circuit may be the same as the fusing characteristics of the fuse elements in the other series circuits.

[0013] The fuse elements in at least one of the series circuits connected in parallel may have melting characteristics different from the fuse elements in the other series circuits connected in parallel.

[0014] The electrical resistance of the resistive element in the at least one series circuit may be the same as the electrical resistance of the resistive element in the other series circuit.

[0015] The device may further include a determination circuit that determines whether the fuse element has been blown.

[0016] In a third aspect of the present invention, there is provided a semiconductor device, which may include the device described above.

[0017] A fourth aspect of the present invention provides a gate driver, which may include the semiconductor device described above.

[0018] In a fifth aspect of the present invention, there is provided a power module, which may include the gate driver.

[0019] The above summary of the invention does not list all of the features of the present invention, and subcombinations of these features may also be inventions. [Brief explanation of the drawings]

[0020] [Figure 1] An example of an IC 10 incorporating a device 100 according to this embodiment is shown. [Figure 2] 1 shows an example of a plan view of IC 10. [Figure 3] 1 shows an example of the relationship between the time until the fuse element 130 melts and the forward current. [Figure 4] An example of an IC 10 equipped with a device 100' according to a first modification of this embodiment is shown. [Figure 5] An example of an IC 10 equipped with a device 100'' according to a second modification of this embodiment is shown. DETAILED DESCRIPTION OF THE INVENTION

[0021] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0022] FIG. 1 shows an example of an IC 10 equipped with a device 100 according to this embodiment. The device 100 according to this embodiment includes a series circuit in which a rectifying element and a fuse element are connected in series. The anode side of the rectifying element in this series circuit is connected to a reference potential, and the cathode side is connected to a potential higher than the reference potential. As a result, the device 100 according to this embodiment can record the occurrence of a negative voltage surge in the IC 10 as a history by melting (including quasi-melting) the fuse element. Note that "connected" here includes not only direct connection of terminals, but also indirect connection of terminals via some kind of element, etc. The same applies hereafter.

[0023] The IC 10 is an integrated circuit in which active and passive elements such as transistors, diodes, resistors, and capacitors are integrated on a single substrate, which may be a semiconductor substrate such as silicon.

[0024] Circuits that achieve various functions may be integrated into the IC 10. In the following description of this embodiment, the IC 10 will be described as a gate driver IC.

[0025] A gate driver is a circuit for driving a power semiconductor by applying a voltage to the gate. Examples of such power semiconductors include a metal oxide semiconductor field effect transistor (MOSFET) and an insulated gate bipolar transistor (IGBT). The IC 10 may have, for example, such a gate driving function. However, the IC 10 is not limited to this. The IC 10 may also have various functions other than the gate driving function.

[0026] The IC 10 includes a first circuit 20, a second circuit 30, and the device 100 according to the present embodiment. That is, a semiconductor device including the device 100 according to the present embodiment may be provided, and in particular, a gate driver including such a semiconductor device may be provided.

[0027] Furthermore, the gate driver may be housed in the same package as a so-called intelligent power module (IPM) together with the power semiconductor and the protection circuit, and therefore a power module incorporating such a gate driver may be provided.

[0028] Furthermore, the power module can be used for power conversion in a motor drive inverter, a DC-DC converter, etc. Therefore, a power conversion device equipped with such a power module may be provided.

[0029] The first circuit 20 and the second circuit 30 may each be a circuit that realizes part of the functions of the IC 10. As an example, if the IC 10 is a gate driver IC, the first circuit 20 and the second circuit 30 may be at least one of a drive circuit for driving the gate of a power semiconductor, a delay circuit, a logic circuit, and a protection circuit.

[0030] The device 100 may be built into an IC 10 to record the occurrence of a negative voltage surge in the IC 10 (or power module, or power conversion device).

[0031] The device 100 includes a parallel circuit. In the drawing, the device 100 includes a first parallel circuit 101a and a second parallel circuit 101b (collectively referred to as "parallel circuits 101") as an example. Note that, although the drawing shows the device 100 including two parallel circuits 101 as an example, the present invention is not limited to this. The device 100 may include only one parallel circuit 101, or may include three or more parallel circuits 101.

[0032] The parallel circuit 101 has a plurality of series circuits connected in parallel. In the figure, a first parallel circuit 101a is shown as an example in which a first series circuit 110x, a second series circuit 110y, and a third series circuit 110z (collectively referred to as "series circuits 110") are connected in parallel. The parallel circuit 101b may have the same configuration as the parallel circuit 101a, and therefore its description will be omitted here. While the figure shows an example in which three series circuits 110 are connected in parallel in the parallel circuit 101, the present invention is not limited to this. In the parallel circuit 101, two series circuits 110 may be connected in parallel, or four or more series circuits 110 may be connected in parallel. Furthermore, the number of series circuits 110 connected in parallel may differ among the plurality of parallel circuits 101.

[0033] In the series circuit 110, a rectifier element and a fuse element are connected in series. In the figure, as an example, in the first series circuit 110x, a first rectifier element 120x and a first fuse element 130x are connected in series, in the second series circuit 110y, a second rectifier element 120y and a second fuse element 130y are connected in series, and in the third series circuit 110z, a third rectifier element 120z and a third fuse element 130z are connected in series. Here, the first rectifier element 120x, the second rectifier element 120y, and the third rectifier element 120z are collectively referred to as "rectifier elements 120." Furthermore, the first fuse element 130x, the second fuse, and the third fuse element 130z are collectively referred to as "fuse elements 130."

[0034] The rectifying element 120 is an element that has a rectifying effect of passing current in only one direction. The rectifying element 120 has a PN junction. A PN junction is a junction formed by joining a p-type semiconductor and an n-type semiconductor, with the p-type semiconductor electrode called the anode and the n-type semiconductor electrode called the cathode. In such a rectifying element 120, when a higher voltage is applied to the cathode side than to the anode side (also referred to as "applying a reverse bias"), the depletion layer at the junction becomes larger, preventing current from flowing in the reverse direction. On the other hand, in the rectifying element 120, when a higher voltage is applied to the anode side than to the cathode side (also referred to as "applying a forward bias"), the depletion layer at the junction becomes smaller (eliminates), allowing current to flow in the forward direction.

[0035] Such rectifying element 120 may be, for example, a dedicated diode or the like. However, this is not limiting. Generally, PN junctions (e.g., PN junctions included in transistors) are provided at various positions inside IC 10 to realize various functions of IC 10. Therefore, such existing PN junctions may be secondarily used as rectifying element 120.

[0036] The fuse element 130 is an element that opens a circuit by fusing internal wiring with Joule heat when a current exceeding the rated value flows. Such elements are generally used as protective components that protect electrical circuits from currents exceeding the rated value or as components for function trimming. In contrast, in the device 100 according to this embodiment, such a fuse element 130 is used to record the occurrence of a negative voltage surge in the IC 10 as a history.

[0037] For example, as shown in the figure, in the series circuit 110, the anode of the rectifying element 120 may constitute one end TA of the series circuit 110 (one end on the anode side of the rectifying element 120 in the series circuit 110). Furthermore, the cathode of the rectifying element 120 may be connected to one end of the fuse element 130. The other end of the fuse element 130 may constitute the other end TC of the series circuit 110 (the other end on the cathode side of the rectifying element 120 in the series circuit 110). However, this is not limiting. For example, the rectifying element 120 and the fuse element 130 may be connected in series in the reverse order. That is, in the series circuit 110, one end of the fuse element 130 may constitute one end TA of the series circuit 110, the other end of the fuse element 130 may be connected to the anode of the rectifying element 120, and the cathode of the rectifying element 120 may constitute the other end TC of the series circuit 110.

[0038] As shown in the figure, in the first parallel circuit 101a, one end TA of the series circuit 110 may be connected to a first first connection point P1a, and the other end TC may be connected to a first second connection point P2a. Here, the first first connection point P1a may be, for example, a connection point having a GND potential of IC10. Also, the first second connection point P2a may be, for example, a connection point having a VCC potential of IC10. Similarly, in the second parallel circuit 101b, one end TA of the series circuit 110 may be connected to a second first connection point P1b, and the other end TC may be connected to a second second connection point P2b. Here, the second first connection point P1b may be, for example, a connection point having a GND potential of IC10. Also, the second second connection point P2b may be, for example, a connection point having a potential between the VCC potential and the GND potential of IC10. Here, the first first connection point P1a and the second first connection point P1b are collectively referred to as the "first connection point P1." Furthermore, the first second connection point P2a and the second second connection point P2b are collectively referred to as the "second connection point P2." In this manner, in the device 100, one end TA on the anode side of the rectifying element 120 in the series circuit 110 is connected to the first connection point P1 having a reference potential, and the other end TC on the cathode side of the rectifying element 120 in the series circuit 110 is connected to the second connection point P2 that should have a potential higher than the reference potential.

[0039] Therefore, under normal circumstances, the potential of the second connection point P2 is higher than the potential of the first connection point P1, and the rectifier element 120 is reverse-biased, so that no current flows through the fuse element 130. However, if a negative voltage surge occurs in the IC 10 due to some abnormality, an inversion phenomenon occurs in which the potential of the first connection point P1 becomes higher than the potential of the second connection point P2, and the rectifier element 120 is forward-biased, so that a current flows through the fuse element 130. If such an overcurrent flows that exceeds the rated current, the fuse element 130 will melt. In other words, the device 100 can record the occurrence of a negative voltage surge as a history by melting the fuse element 130.

[0040] As described above, the device 100 according to this embodiment includes a series circuit 110 in which a rectifying element 120 and a fuse element 130 are connected in series. One end TA on the anode side of the rectifying element 120 in the series circuit 110 is connected to a first connection point P1 having a reference potential, and the other end TC on the cathode side of the rectifying element 120 in the series circuit 110 is connected to a second connection point P2 that should have a potential higher than the reference potential. As a result, the device 100 according to this embodiment can indicate whether a negative voltage surge has occurred in the IC 10 due to the fuse element 130 blowing, thereby providing information for determining whether a failure of the IC 10 has occurred.

[0041] FIG. 2 shows an example of a plan view of an IC 10. This diagram illustrates an example in which five parallel circuits 101, namely, a first parallel circuit 101a, a second parallel circuit 101b, a third parallel circuit 101c, a fourth parallel circuit 101d, and a fifth parallel circuit 101e, are built into the IC 10. In this case, the parallel circuits 101 may be provided at the ends of the IC, as with the first parallel circuit 101a to the fourth parallel circuit 101d, or may be provided in the center of the IC, as with the fifth parallel circuit 101e. It is particularly desirable to place the parallel circuits 101 near circuits within the IC 10 that are prone to negative voltage surges.

[0042] Here, as described above, in the parallel circuit 101, a plurality of series circuits 110 are connected in parallel, each of which has a rectifying element 120 and a fuse element 130 connected in series. In this case, it is preferable that the plurality of series circuits 110 connected in parallel are configured so that the time until the fuse element 130 melts due to an overcurrent differs from one another.

[0043] As an example, the first rectifier 120x, the second rectifier 120y, and the third rectifier 120z may be configured to have different rectification characteristics. As described above, the rectifier 120 has a PN junction. Here, the forward current at the PN junction depends on the junction area between the p-type semiconductor and the n-type semiconductor. That is, when the PN junction area is small, the resistance component increases, and therefore the forward current decreases. On the other hand, when the PN junction area is large, the resistance component decreases, and therefore the forward current increases. Therefore, in multiple series circuits 110 connected in parallel, the PN junction junction areas may be made different from one another to make the rectifier elements 120 have different rectification characteristics.

[0044] For example, the PN junction areas may be set as follows: first rectifier element 120x<second rectifier element 120y<third rectifier element 120z. In this case, the resistance components are first rectifier element 120x>second rectifier element 120y>third rectifier element 120z. Therefore, the magnitude of the forward current is set as follows: first rectifier element 120x<second rectifier element 120y<third rectifier element 120z.

[0045] In this case, if the first fuse element 130x, the second fuse element 130y, and the third fuse element 130z have the same melting characteristics, the time until the fuse element 130 melts can be made different in the first series circuit 110x, the second series circuit 110y, and the third series circuit 110z.

[0046] In the above description, the rectifying characteristics of the rectifying elements 120 are different among all the series circuits 110 connected in parallel. However, this is not limiting. It is sufficient that the rectifying characteristics of the rectifying element 120 in at least one series circuit 110 connected in parallel differ from the rectifying characteristics of the rectifying elements in the other series circuits 110 connected in parallel. More specifically, it is sufficient that the junction area of ​​the PN junction in the at least one series circuit 110 differs from the junction area of ​​the PN junction in the other series circuits 110. In this case, it is sufficient that the melting characteristics of the fuse element 130 in the at least one series circuit 110 are the same as the melting characteristics of the fuse element 130 in the other series circuits 110. This allows the time until the fuse element 130 melts in at least one series circuit 110 to differ from that in the other series circuits 110.

[0047] In the above description, the expression "different" is used for characteristics, etc., but "different" here means that the characteristics are different in terms of design specifications, and does not include cases where there are only slight differences, such as manufacturing errors. Also, in the above description, the expression "same" is used for characteristics, etc., but "same" here means that the characteristics are the same in terms of design specifications, and does not include cases where there are only slight differences, such as manufacturing errors. The same applies hereafter.

[0048] 3 shows an example of the relationship between the time until the fuse element 130 melts and the forward current. This figure shows the relationship between the time until the first fuse element 130x, the second fuse element 130y, and the third fuse element 130z melt and the forward current when the PN junction areas are set as follows: first rectifier element 120x<second rectifier element 120y<third rectifier element 120z. It is assumed that the first fuse element 130x, the second fuse element 130y, and the third fuse element 130z have the same melting characteristics.

[0049] In this figure, the horizontal axis indicates the time until fuse element 130 blows, with the time decreasing toward the left and increasing toward the right. Also, in this figure, the vertical axis indicates the magnitude of the forward current, with the value decreasing toward the bottom and increasing toward the top.

[0050] For example, with respect to the first series circuit 110x, the junction area of ​​the PN junction in the first rectifier element 120x is relatively small, so the forward current Ix in the first series circuit 110x is relatively small. Here, the fuse element 130 fuses its internal wiring by Joule heat, so the time Tx until the first fuse element 130x fuses is relatively long. On the other hand, with respect to the third series circuit 110z, the junction area of ​​the PN junction in the third rectifier element 120z is relatively large, so the forward current Iz in the third series circuit 110z is relatively large. And the time Tz until the third fuse element 130z fuses is relatively short. With respect to the second series circuit 110y, the relationship is the same as that between the first series circuit 110x and the third series circuit 110z.

[0051] For example, if the first fuse element 130x is blown but the second fuse element 130y and the third fuse element 130z are not blown, it can be determined that a relatively small current has flowed for a long time. Similarly, if the third fuse element 130z is blown but the first fuse element 130x and the second fuse element 130y are not blown, it can be determined that a relatively large current has flowed for a short time. Therefore, in a failure analysis of the IC 10, it is possible to predict the amount of current and the elapsed time of a negative voltage surge that has occurred in the IC 10 based on such determination information. As described above, according to the device 100 of this embodiment, the multiple series circuits 110 connected in parallel are configured so that the time until the fuse element 130 is blown due to an overcurrent varies from one another. Therefore, the occurrence of a negative voltage surge can be recorded as a history so that the amount of current and the elapsed time due to a negative voltage surge can be predicted.

[0052] In the above description, a case has been shown as an example in which the rectifying characteristics of the rectifying elements 120, more specifically, the junction areas of the PN junctions, of the multiple series circuits 110 connected in parallel are made different to make the times until the fuse elements 130 melt down different from each other. However, this is not limiting. The melting characteristics of the fuse elements 130 of the multiple series circuits 110 connected in parallel may be made different to make the times until the fuse elements 130 melt down different from each other.

[0053] That is, the fusing characteristics of the fuse element 130 in at least one series circuit 110 connected in parallel may be different from the fusing characteristics of the fuse elements 130 in the other series circuits 110 connected in parallel. In this case, the rectifying characteristics of the rectifying element 120 in the at least one series circuit 110 may be the same as the rectifying characteristics of the rectifying elements 120 in the other series circuits 110. In other words, in multiple series circuits 110 connected in parallel, the rectifying characteristics of the rectifying elements 120 may be the same so that the same magnitude of forward current flows, but the fusing characteristics of the fuse elements 130 may be different from one another, thereby making the times until the fuse elements 130 melt down different from one another.

[0054] FIG. 4 shows an example of an IC 10 equipped with a device 100′ according to a first modification of this embodiment. In FIG. 4, components having the same functions and configurations as those in FIG. 1 are denoted by the same reference numerals, and descriptions thereof will be omitted hereinafter except for differences. In the above-described embodiment, a case in which a rectifying element 120 and a fuse element 130 are connected in series in a series circuit 110 is shown as an example. This has the advantage that, under normal circumstances, a reverse bias is applied to the rectifying element 120, and therefore the series circuit 110 does not affect the IC 10. However, in this embodiment, the current direction is limited to one direction, and therefore it can only handle surges occurring in one direction (negative voltage direction in the above description).

[0055] Therefore, in the first modified example, a resistive element 400 is used instead of the rectifying element 120. That is, in the series circuit 110, the resistive element 400 and the fuse element 130 are connected in series. In the present figure, as an example, in the first series circuit 110x, the first resistive element 400x and the first fuse element 130x are connected in series, in the second series circuit 110y, the second resistive element 400y and the second fuse element 130y are connected in series, and in the third series circuit 110z, the third resistive element 400z and the third fuse element 130z are connected in series. Here, the first resistive element 400x, the second resistive element 400y, and the third resistive element 400z are collectively referred to as "resistive elements 400."

[0056] The resistive element 400 is an element having electrical resistance. Such resistive element 400 may be, for example, a dedicated resistor. However, the present invention is not limited to this. Generally, wiring is provided at various positions inside the IC 10 to realize various functions of the IC 10. Therefore, such existing wiring may be secondarily used as the resistive element 400.

[0057] For example, as shown in the figure, in the series circuit 110, one end of the resistive element 400 may constitute one end TR of the series circuit 110 (also referred to as one end of the parallel circuit 101). The other end of the resistive element 400 may be connected to one end of the fuse element 130. The other end of the fuse element 130 may constitute the other end TS of the series circuit 110 (also referred to as the other end of the parallel circuit 101). However, this is not limiting. For example, the resistive element 400 and the fuse element 130 may be connected in series in the reverse order. That is, in the series circuit 110, one end of the fuse element 130 may constitute one end TR of the series circuit 110, the other end of the fuse element 130 may be connected to one end of the resistive element 400, and the other end of the resistive element 400 may constitute the other end TS of the series circuit 110.

[0058] As shown in the figure, one end TR of the first parallel circuit 101a may be connected to the first first connection point P1a, and the other end TS may be connected to the first second connection point P2a. Similarly, one end TR of the second parallel circuit 101b may be connected to the second first connection point P1b, and the other end TS may be connected to the second second connection point P2b. In this way, in the device 100', one end TR of the parallel circuit 101 is connected to the first connection point P1 having a reference potential, and the other end of the parallel circuit 101 is connected to the second connection point P2 that should have a potential higher than the reference potential.

[0059] In this case, also in the device 100' according to the first modification, it is preferable that the multiple series circuits 110 connected in parallel have different times until the fuse element 130 melts due to an overcurrent. That is, the device 100' according to the first modification may include a parallel circuit 101 in which multiple series circuits 110 are connected in parallel, each of which has a resistive element 400 and a fuse element 130 connected in series and has different times until the fuse element 130 melts due to an overcurrent.

[0060] For example, the first resistive element 400x, the second resistive element 400y, and the third resistive element 400z may be configured to have different electrical resistances. For example, the electrical resistances may be first resistive element 400x > second resistive element 400y > third resistive element 400z. In this case, the magnitude of the forward current is first resistive element 400x < second resistive element 400y < third resistive element 400z.

[0061] In this case, if the first fuse element 130x, the second fuse element 130y, and the third fuse element 130z have the same melting characteristics, the time until the fuse element 130 melts can be made different in the first series circuit 110x, the second series circuit 110y, and the third series circuit 110z.

[0062] In the above description, the electrical resistance of the resistive elements 400 is made different among all of the series circuits 110 connected in parallel, but this is not limiting. It is sufficient that the electrical resistance of the resistive element 400 in at least one series circuit 110 connected in parallel is different from the electrical resistance of the resistive elements 400 in the other series circuits 110 connected in parallel. In this case, it is sufficient that the melting characteristics of the fuse element 130 in the at least one series circuit 110 are the same as the melting characteristics of the fuse element 130 in the other series circuits 110. This allows the time until the fuse element 130 in at least one series circuit 110 melts to be different from that in the other series circuits 110.

[0063] In the above description, a case has been shown as an example in which the electrical resistance of the resistive elements 400 in the plurality of series circuits 110 connected in parallel is made different to make the time until the fuse elements 130 melt down different from each other. However, this is not limiting. The time until the fuse elements 130 melt down may also be made different from each other by making the melting characteristics of the fuse elements 130 in the plurality of series circuits 110 connected in parallel.

[0064] That is, the fusing characteristics of the fuse element 130 in at least one series circuit 110 connected in parallel may be different from the fusing characteristics of the fuse elements 130 in the other series circuits 110 connected in parallel. In this case, the electrical resistance of the resistive element 400 in at least one series circuit 110 may be the same as the electrical resistance of the resistive element 400 in the other series circuits 110. In other words, in a plurality of series circuits 110 connected in parallel, the resistive elements 400 may have the same electrical resistance so that the same amount of current flows, but the fuse elements 130 may have different fusing characteristics, thereby making the times until the fuse elements 130 melt down different from one another.

[0065] As described above, the device 100′ according to the first modification uses the resistive element 400 instead of the rectifying element 120. Therefore, the current direction is not limited to one direction, and it is possible to cope with surges occurring in the positive voltage direction as well as in the negative voltage direction.

[0066] FIG. 5 shows an example of an IC 10 equipped with a device 100" according to a second modified example of this embodiment. In FIG. 5, components having the same functions and configurations as those in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted hereinafter except for differences. In addition to the functions of the device 100 according to the above-described embodiment, the device 100" according to the second modified example has a function of determining whether a fuse element has blown. The device 100" according to the second modified example further includes a determination circuit 500.

[0067] The determination circuit 500 determines whether the fuse element 130 has blown (including semi-blown). In the present diagram, a case where the determination circuit 500 is connected in parallel between the second first connection point P1b and the second second connection point P2b is shown as an example. In such a case, the determination circuit 500 determines whether the fuse element 130 has blown by, for example, measuring the voltage between the first connection point P1 and the second connection point P2. More specifically, the determination circuit 500 may determine that the fuse element 130 has blown if the measured voltage between the terminals is different from the voltage between the terminals when the fuse element 130 is not blown.

[0068] However, the present invention is not limited to this. The determination circuit 500 may be connected in series between the first connection point P1 and the second connection point P2. In such a case, the determination circuit 500 may determine whether the fuse element 130 has blown by, for example, measuring the current between the first connection point P1 and the second connection point P2. More specifically, the determination circuit 500 may determine that the fuse element 130 has blown if the measured current between the terminals is different from the current between the terminals when the fuse element 130 is not blown.

[0069] It should be noted that multiple thresholds may be provided for comparison with the measured value in such a determination circuit 500. That is, four thresholds may be set in advance from experimental data or the like, corresponding to when none of the fuse elements 130 are blown, when one fuse element is blown, when two fuse elements are blown, and when all fuse elements are blown, and the determination circuit 500 may determine how many of the fuse elements 130 are blown by comparing the measured value with these multiple thresholds.

[0070] As described above, the device 100'' according to the second modification further includes a determination circuit 500 that determines whether the fuse element 130 has been blown. As a result, the device 100'' according to the second modification can eliminate the need for a separate analysis of whether the fuse element 130 has been blown.

[0071] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0072] It should be noted that the execution order of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order. According to this specification, the following items are also disclosed. [Item 1] a series circuit in which a rectifying element and a fuse element are connected in series; One end on the anode side of the rectifier element in the series circuit is connected to a first connection point having a reference potential, and the other end on the cathode side of the rectifier element in the series circuit is connected to a second connection point that should have a potential higher than the reference potential. device. [Item 2] Item 1. The device according to item 1, further comprising a parallel circuit in which a plurality of the series circuits are connected in parallel. [Item 3] Item 3. The device according to item 2, wherein the rectifying characteristics of the rectifying elements in at least one of the series circuits connected in parallel are different from the rectifying characteristics of the rectifying elements in the other series circuits connected in parallel. [Item 4] The rectifying element has a PN junction, Item 4. The device according to item 3, wherein the junction area of ​​the PN junction in the at least one series circuit is different from the junction area of ​​the PN junction in the other series circuits. [Item 5] 5. The device according to item 3 or 4, wherein the fusing characteristics of the fuse elements in the at least one series circuit are the same as the fusing characteristics of the fuse elements in the other series circuits. [Item 6] 3. The device of claim 2, wherein the fuse element in at least one of the series circuits connected in parallel has a melting characteristic different from the fuse elements in the other series circuits connected in parallel. [Item 7] Item 7. The device according to item 6, wherein the rectifying characteristics of the rectifying elements in the at least one series circuit are the same as the rectifying characteristics of the rectifying elements in the other series circuits. [Item 8] a parallel circuit in which a plurality of series circuits are connected in parallel, each of which has a resistive element and a fuse element connected in series, and the series circuits have different times until the fuse element melts down due to an overcurrent; One end of the parallel circuit is connected to a first connection point having a reference potential, and the other end of the parallel circuit is connected to a second connection point having a potential higher than the reference potential. device. [Item 9] Item 9. The device of item 8, wherein the electrical resistance of the resistive element in at least one of the parallel-connected series circuits is different from the electrical resistance of the resistive element in the other parallel-connected series circuits. [Item 10] Item 10. The device of item 9, wherein the fusing characteristics of the fuse elements in the at least one series circuit are the same as the fusing characteristics of the fuse elements in the other series circuits. [Item 11] Item 9. The device of item 8, wherein the fusing characteristics of the fuse elements in at least one of the parallel-connected series circuits are different from the fusing characteristics of the fuse elements in the other parallel-connected series circuits. [Item 12] Item 12. The device of item 11, wherein the electrical resistance of the resistive element in the at least one series circuit is the same as the electrical resistance of the resistive element in the other series circuit. [Item 13] 13. The device of any one of items 1 to 12, further comprising a determination circuit that determines whether the fuse element has been blown. [Item 14] 14. A semiconductor device equipped with the device according to any one of items 1 to 13. [Item 15] Item 15. A gate driver equipped with the semiconductor device according to item 14. [Item 16] Item 16. A power module equipped with the gate driver according to item 15. [Explanation of symbols]

[0073] 10 IC 20 1st circuit 30 2nd circuit 100 devices 101 parallel circuit 101a First parallel circuit 101b Second parallel circuit 101c Third parallel circuit 101d Fourth Parallel Circuit 101e Fifth Parallel Circuit 110 Series Circuit 110x 1st series circuit 110y 2nd series circuit 110z 3rd series circuit 120 Rectifier 120x First rectifier 120y Second rectifying element 120z Third rectifier element 130 Fuse element 130x First Fuse Element 130y Second fuse element 130z Third fuse element 400 Resistive Elements 400x first resistive element 400y Second resistive element 400z Third resistive element 500 Judgment circuit

Claims

1. a parallel circuit in which a plurality of series circuits are connected in parallel, each of which has a rectifying element and a fuse element connected in series, each of which has a rectifying function of passing current in only one direction, and the series circuits have different times until the fuse element melts down due to a negative voltage surge; One end on the anode side of the rectifying element in each of the plurality of series circuits is connected to a first connection point having a reference potential, and the other end on the cathode side of the rectifying element in each of the plurality of series circuits is connected to a second connection point that should have a potential higher than the reference potential. device.

2. 2. The device of claim 1, wherein the rectifying characteristics of the rectifying elements in at least one of the plurality of series circuits connected in parallel are different from the rectifying characteristics of the rectifying elements in other of the plurality of series circuits connected in parallel.

3. the rectifying element has a PN junction, The device of claim 2 , wherein a junction area of ​​a PN junction in at least one of the plurality of series circuits is different from a junction area of ​​a PN junction in the other of the plurality of series circuits.

4. A device as described in claim 2 or 3, wherein the melting characteristics of the fuse element in at least one of the plurality of series circuits are the same as the melting characteristics of the fuse element in the other of the plurality of series circuits.

5. 2. The device of claim 1, wherein a fuse element in at least one of the plurality of series circuits connected in parallel has a melting characteristic that is different from a fuse element in another of the plurality of series circuits connected in parallel.

6. A device as described in claim 5, wherein the rectifying characteristics of the rectifying elements in at least one of the plurality of series circuits are the same as the rectifying characteristics of the rectifying elements in the other series circuits of the plurality of series circuits.

7. The device according to claim 1 , further comprising a determination circuit that determines whether the fuse element has been blown.

8. A semiconductor device comprising the device according to claim 1 .

9. A gate driver equipped with the semiconductor device according to claim 8.

10. A power module equipped with the gate driver according to claim 9.

Images