JP5404432B2 - Semiconductor device and drive circuit using the same - Google Patents

Description

  The present invention relates to a semiconductor device including a switching element, and more particularly to a technique for temperature detection (measurement) of the switching element.

  In power electronics equipment, a silicon IGBT (Insulated Gate Bipolar Transistor), a silicon MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or the like is used as a switching element for switching execution / stop of power supply to a load (motor, etc.). In recent years, adoption of a silicon carbide MOSFET as a switching element for controlling a high voltage higher than about 1 kV has been studied. These are all insulated gate semiconductor elements.

  Some semiconductor devices including a switching element for power control have a function (overcurrent protection function) for preventing destruction of the switching element due to an overcurrent generated when a load is short-circuited. A typical example is a semiconductor device that has an element for detecting a current flowing through a switching element (current sense element), and is controlled so that the switching element is turned off when an overcurrent is detected.

  Generally, a rated temperature (a maximum temperature that guarantees a normal operation of the switching element) is set for the switching element. A semiconductor device having a function (temperature protection function) for protecting the switching element by stopping driving when the switching element reaches a rated temperature or more has been proposed (for example, Patent Documents 1 and 2 below).

  In order to realize the temperature protection function, the semiconductor device needs to have a function of detecting the temperature of the switching element. For example, in the semiconductor device of Patent Document 1, a temperature detecting diode (120) is installed in the vicinity of the switching element (110), and the temperature of the switching element is detected by detecting the forward voltage drop. Furthermore, the semiconductor device of Patent Document 1 calculates the current flowing through the switching element using the current sense element, and multiplies the power calculated based on the current by the thermal resistance between the switching element and the temperature detection diode. The correction temperature (temperature difference between the position of the temperature detection diode and the junction of the switching element) is obtained. The correct temperature is added to the temperature detected by the temperature detecting diode to calculate the accurate temperature of the junction of the switching element, thereby realizing a more appropriate temperature protection function.

  Further, in the semiconductor device of Patent Document 2, during a period in which the power bipolar transistor (4) that is a switching element is turned off, a constant minute current that does not intentionally turn on the power bipolar transistor is applied to a pn junction between its base and emitter ( The temperature of the power bipolar transistor is detected by detecting the forward voltage. That is, the semiconductor device of Patent Document 2 uses a parasitic diode between the base and emitter as a diode for temperature detection, and is configured to detect the temperature of the switching element without providing a special temperature detection means. Yes.

JP 2004-117111 A JP 2002-289856 A

  As described above, in the semiconductor device of Patent Document 1, the temperature of the switching element is calculated using the temperature detection diode and the current sense element provided in the switching element. Therefore, it is necessary to dispose the temperature detecting diode and the current sensing element in the same semiconductor chip as the switching element. In addition, in order to calculate the temperature of the switching element, it is necessary to input a signal corresponding to the forward voltage of the temperature detection diode or a signal obtained by converting the current flowing through the current sensing element into a voltage to an arithmetic unit outside the chip. is there.

  Therefore, pads for taking out these signals must be provided on the chip separately from the terminals of the switching elements. Therefore, there is a problem that the chip area increases. In particular, in the method disclosed in Patent Document 1, when both current detection and temperature detection of the switching device are performed, it is necessary to separately provide a current detection pad and a temperature detection pad.

  In this regard, the semiconductor device of Patent Document 2 can detect the temperature of the switching element without providing a special temperature detecting means. However, since the temperature is detected by passing a minute current through a diode formed by the pn junction between the base and emitter of the bipolar transistor in the off state, the applicable range is forward from the control circuit in the off state. The switching element is limited to a structure having a pn junction through which a current can flow.

  For example, since a current cannot flow between the gate and the source, such as an IGBT or a MOSFET, the temperature detection method of Patent Document 2 cannot be applied. That is, in order to detect the temperature of the gate-insulated switching element using a diode, it is necessary to separately provide a temperature detection diode and a pad for extracting a signal from the same chip as the switching element.

  In particular, since the silicon carbide switching element capable of increasing the current density can remarkably reduce the formation area as compared with the silicon switching element, the disadvantage that the chip area increases due to the increase in the number of pads provided on the chip is silicon carbide. It is very large for a semiconductor device provided with a switching element.

  The present invention has been made to solve the above problems, and can detect the temperature of a switching element without increasing the number of pads provided on a semiconductor chip, and can be applied to an insulated gate switching element. An object of the present invention is to provide a semiconductor device having the characteristics.

A semiconductor device according to the present invention includes a main switching element, a series circuit of a current sensing element and a resistance element, which are connected in parallel to the main switching element and for detecting a current that is set to flow less than the main switching element. the current based on the voltage of the sense terminal connected between the sense element and the resistive element, the reverse recovery time reverse recovery current is the time that has flowed to the parasitic diode of the current sense element, the main switching element is rated A reverse recovery time detection circuit that detects whether or not the reverse recovery time is longer than the case of temperature, and determines whether or not the temperature of the main switching element exceeds a rated value based on the detection result. The reverse recovery time detection circuit has a predetermined voltage at the sense terminal at a predetermined timing immediately after the main switching element is turned on. By comparing the values, the reverse recovery time the main switching device detects whether longer or not than the reverse recovery time when the rated temperature, the predetermined threshold value, the main switching element is at the rated temperature In some cases, the voltage is equal to the voltage of the sense terminal at the predetermined timing.

  Since the reverse recovery time of the parasitic diode of the current sense element has a correlation with the temperature of the main switching element, the temperature of the main switching element can be detected according to the present invention. The temperature detection (reverse recovery time detection) is performed using a sense terminal that is also used to detect the main current flowing through the main switching element, so it is necessary to provide a dedicated pad for temperature detection on the main switching element chip. Absent. In particular, this effect is very effective for a semiconductor device including a silicon carbide switching element that is known to be able to significantly reduce the chip area. Further, since temperature detection is performed using a reverse recovery current caused by the return current, it can also be applied to an insulated gate type switching element.

It is a circuit diagram which shows the structure of the semiconductor device which concerns on this invention. It is a figure explaining reverse recovery current and reverse recovery time. It is a figure explaining reverse recovery current and reverse recovery time. It is a block diagram of the inverter circuit comprised using the semiconductor device which concerns on this invention. FIG. 5 is a waveform diagram of drive signals of the inverter circuit of FIG. 4. It is a figure for demonstrating the temperature detection operation | movement in the semiconductor device which concerns on this invention. It is a figure for demonstrating the temperature detection operation | movement in the semiconductor device which concerns on this invention. It is a voltage waveform diagram output to the sense voltage terminal of the switching device according to the present invention. FIG. 9 is an enlarged view of a peak portion due to a reverse recovery current of the voltage waveform of FIG. 8. It is a graph which shows the temperature characteristic of the reverse recovery time in a pn junction. 6 is a diagram for explaining a temperature detection method of a main switching element in the first embodiment. FIG. FIG. 9 is a diagram for explaining a temperature detection method for a main switching element in a second embodiment. FIG. 10 is a diagram for illustrating a temperature detection method for a main switching element in a third embodiment.

<Embodiment 1>
FIG. 1 is a circuit diagram showing a configuration of a semiconductor device according to the present invention. The semiconductor device includes a switching device 10 and a current detection circuit 4 and a reverse recovery time detection circuit 5 connected to the sense voltage terminal SE. The switching device 10 includes a main switching element 1 that controls power supplied to a load by switching of a power supply, and a series circuit of a current sense element 2 and a sense resistor 3 connected in parallel to the main switching element 1. The sense voltage terminal SE is provided at a connection node between the current sense element 2 and the sense resistor 3.

  In the present embodiment, it is assumed that main switching element 1 and current sense element 2 are MOSFETs formed using silicon carbide. The current sense element 2 has a smaller number of cells than the main switching element 1 so that a sense current smaller than the current flowing through the main switching element 1 (about 1/5000 to 1/10000 of the current flowing through the main switching element 1) flows. It is comprised by. The sense resistor 3 converts a current (sense current) flowing through the current sense element 2 into a voltage Vs (hereinafter referred to as “sense voltage”). The lifetime of main switching element 1 and current sense element 2 (time until minority carriers disappear) is about several nsec to several μsec, but the lifetime of main switching element 1 is longer than the lifetime of current sense element 2. Is also set short. The lifetime can be controlled by electron beam irradiation, ion irradiation, radiation irradiation, or the like.

  The current detection circuit 4 detects the current value flowing through the main switching element 1 based on the sense voltage Vs generated in the sense resistor 3 by the current flowing through the current sense element 2. The reverse recovery time detection circuit 5 measures the time when the reverse recovery current flows, that is, the reverse recovery time based on the sense voltage Vs when the reverse recovery current flows through the parasitic diode of the current sensing element 2, and uses the measured value as the measured value. Based on this, the temperature of the main switching element 1 is detected.

  Here, the reverse recovery current and the reverse recovery time will be described. For example, as shown in FIG. 2, consider the case where the cathode of the pn junction diode 6 is connected to the ground potential 7 and the anode is connected to the rectangular voltage generator 8. When the rectangular voltage generator 8 outputs a positive voltage, a forward current flows in the direction from the anode to the cathode (solid arrow in FIG. 2) in the pn junction diode 6. When the output of the rectangular voltage generator 8 changes to a negative voltage from that state, the reverse current is specified in the direction from the cathode to the anode (broken arrow in FIG. 2) in the pn junction diode 6 due to the minority carrier accumulation effect of the pn junction. It flows only for the time. This reverse current is the reverse recovery current, and the time during which it flows is called the reverse recovery time.

  FIG. 3 is a waveform diagram of the reverse recovery current generated in the pn junction diode 6 in the example of FIG. The magnitude of the reverse recovery current becomes maximum immediately after the anode voltage is switched from positive to negative (that is, immediately after the pn junction diode 6 is turned off), and then gradually decreases to zero. The period in which the reverse recovery current flows is from the time ta when the direction of the current is switched from the forward direction to the reverse direction until the time tb when the current value becomes 0. It is often the time from when the flow starts (time ta) until the magnitude of the reverse recovery current decreases to 10% of the maximum value. The method for estimating the reverse recovery time in the present invention will be described later. It has also been found that the reverse recovery time is shortened when the lifetime is shortened.

  In the present embodiment, the temperature of main switching element 1 is detected based on the length of time (reverse recovery time) during which a reverse recovery current generated in the parasitic diode of current sensing element 2 flows. Hereinafter, the temperature detection method will be described.

  FIG. 4 is a configuration diagram of an inverter circuit configured using the semiconductor device of FIG. The inverter circuit is a drive circuit that drives the load 9 by switching a power supply VB by a series circuit composed of the switching devices 10a and 10b and a series circuit composed of the switching devices 10c and 10d.

  The switching devices 10a to 10b shown in FIG. 4 have the same configuration as the switching device 10 of FIG. Although not shown in FIG. 4, each of the sense voltage terminals SE of the switching devices 10a to 10d is connected to the current detection circuit 4 and the reverse recovery time detection circuit 5 as shown in FIG. Hereinafter, for convenience, the switching devices 10a and 10c may be referred to as “upper switching devices” and the switching devices 10b and 10d may be referred to as “lower switching devices”.

  The load 9 is an inductive load such as a motor. The load 9 is connected between a connection node between the switching devices 10a and 10b and a connection node between the switching devices 10c and 10d.

  In an inverter circuit using silicon carbide switching elements, a Schottky barrier diode free-wheeling diode is often connected in parallel to each switching element. However, in the present invention, a parasitic diode composed of a pn junction between the source and the drain of the main switching element 1 and the current sensing element 2 (MOSFET) is used as a freewheeling diode without using it.

  FIG. 5 is a voltage waveform diagram of drive signals V1 to V4 for driving the switching devices 10a to 10d. As shown in FIG. 5, the drive signal V1 of the upper switching device 10a and the drive signal V2 of the lower switching device 10b are activated alternately (H (High) level), and the drive signal V3 of the upper switching device 10c and the lower side The drive signal V4 of the switching device 10d is also activated alternately. The drive signals V1 and V4 are in phase with each other, and the drive signals V2 and V3 are also in phase with each other.

  Generally, in order to reliably prevent the upper and lower switching devices (for example, the upper switching device 10a and the lower switching device 10b) from being turned on at the same time, between the active periods of both drive signals. A fixed margin period (time t2 to t3 in FIG. 5) called a dead time is provided. In this dead time, both the upper and lower switching devices are turned off.

  Referring to FIG. 5, in the period from time t1 to t2 when drive signals V1 and V4 are at the H level, upper switching device 10a and lower switching device 10d are turned on, and the main current flows in the path indicated by the broken-line arrow shown in FIG. Flowing.

  When the drive signals V1 and V4 are deactivated (at L (Low) level) at time t2, both the upper switching device 10a and the lower switching device 10d are turned off, and the main current is cut off. A period from time t2 to time t3 when the drive signals V2 and V3 become H level next is a dead time. During this dead time, the energy accumulated in the inductive load 9 is released, so that the return current flows through the path indicated by the broken arrow shown in FIG. This reflux current flows in the forward direction through the parasitic diodes of the main switching element 1 and the current sensing element 2 of the switching devices 10b and 10c.

  Thereafter, at time t3, when the drive signals V2 and V3 become H level and the lower switching device 10b and the upper switching device 10c are turned on, the parasitic diodes of the main switching device 1 and the current sensing device 2 are turned off. As described above, during the dead time, the reverse recovery current flows through the parasitic diodes of the main switching element 1 and the current sensing element 2 of the switching devices 10b and 10c in the forward direction. When is turned off, a reverse recovery current flows through these parasitic diodes.

  Since the reverse recovery current that flows through the parasitic diode of the current sense element 2 flows through the sense resistor 3, it also appears in the waveform of the sense voltage Vs. FIG. 8 is a waveform diagram of the sense voltage Vs output to the sense voltage terminal SE of the lower switching device 10b. As shown in the figure, a peak due to the reverse recovery current appears in the sense voltage Vs of the lower switching device 10b at the time t3 when it is turned on. When the reverse recovery current becomes 0, the sense voltage Vs has a value proportional to the current flowing through the main switching element 1. FIG. 9 shows an enlarged view of the peak portion due to the reverse recovery current of the sense voltage Vs shown in FIG. Times tR1 to tR2 in FIG. 9 are periods in which a reverse recovery current flows through the parasitic diode of the current sense element 2.

  FIG. 10 is a graph showing the temperature characteristics of the reverse recovery time in the pn junction. It is known that the reverse recovery time becomes longer in proportion to the temperature as shown in the figure (Shoji Ogata, four others, "Static characteristics of 3kV 600A 4H-SiC flat pn diode", IEEJ Transactions B, 126: 7, p.663-p.668, 2006).

  Therefore, the reverse recovery time detection circuit 5 connected to the sense voltage terminal SE can detect the temperature of the current sense element 2 by estimating the reverse recovery time from the waveform of the reverse recovery current appearing in the sense voltage Vs. Since the current sense element 2 is disposed in the same semiconductor chip as the main switching element 1, the temperatures of the current sense element 2 and the main switching element 1 are substantially equal. Therefore, by detecting the temperature of the current sensing element 2, the temperature of the main switching element 1 can be known.

  Here, the timing for detecting the temperature of the main switching element 1 and the current sensing element 2 will be described. In the present invention, the temperature is detected using the waveform of the sense voltage Vs, but the sense voltage Vs is also used for the original purpose of detecting the main current flowing through the main switching element 1. If the current detection circuit 4 detects the main current based on the sense voltage Vs when the reverse recovery current is flowing, the main current cannot be accurately detected, and the overcurrent protection function is erroneously operated. There is a concern. Therefore, the current detection by the current detection circuit 4 needs to be performed during a period when the reverse recovery current is not flowing.

The reverse recovery current in the parasitic diode of the current sense element 2 flows during the period immediately after the switching device 10 is turned on, for example, from the time tR1 to tR2 in FIG. 9 in the case of the lower switching device 10b. In the present embodiment, the reverse recovery time detection circuit 5 performs a predetermined period (a period including at least the times tR1 to tR2 of FIG. 9) immediately after the turn-on, in which the reverse recovery current is assumed to flow through the parasitic diode of the current sense element 2. The temperature detection period. Thereafter, the temperature detection period and the current detection period are divided into periods of current detection by the current detection circuit 4 . As a result, erroneous detection of current and temperature can be avoided and the accuracy thereof can be increased.

  Next, a method for estimating the reverse recovery time in the present embodiment will be described. In the present embodiment, a predetermined threshold voltage Vs1 is set as shown in FIG. 11, and a time tR when the sense voltage Vs is equal to or higher than the threshold voltage Vs1 is defined as a reverse recovery time. Since the time tR is correlated with the time during which the reverse recovery current flows (time tR1 to tR2 in FIG. 9), the time tR also has a characteristic proportional to the temperature as shown in FIG. Therefore, the temperatures of the main switching element 1 and the current sensing element 2 can be detected from the time tR.

  As described above, the semiconductor device according to the present embodiment detects the temperature of the main switching element 1 using a part of the waveform of the sense voltage Vs output from the sense voltage terminal SE of the switching device 10. That is, the sense voltage terminal SE can be shared by the current detection circuit 4 that detects the current of the main switching element 1 and the reverse recovery time detection circuit 5 that detects the temperature. That is, it is not necessary to provide a pad dedicated to temperature detection on the chip of the switching device 10. Compared to a conventional switching device having both a current detection function and a temperature detection function (for example, Patent Document 1), the area can be reduced by at least one pad. In particular, this effect is very effective for a semiconductor device including a silicon carbide switching element that is known to be able to significantly reduce the chip area.

  Since the temperature detection is performed using a reverse recovery current caused by the return current in the parasitic diode of the current sense element 2, it can also be applied to an insulated gate type switching element. Moreover, since temperature detection is performed using the parasitic diode of the current sense element 2 disposed in the vicinity of the main switching element 1, the junction temperature in the vicinity of the main switching element 1 can be detected. The current sensing element 2 is preferably arranged at the center of the chip of the main switching element 1, but may be arranged at the chip end. When arranged at the end of the chip, it is preferable to set the value of the threshold voltage Vs1 that defines the reverse recovery time in consideration of the temperature difference between the center and end of the chip.

  Furthermore, in this embodiment, the reverse recovery time in the parasitic diode of the main switching element 1 is shortened by making the lifetime of the main switching element 1 shorter than the lifetime of the current sensing element 2. Thereby, the power loss by the reverse recovery current of the parasitic diode of the main switching element 1 can be suppressed.

  The sense resistor 3 connected to the current sense element 2 may be built in the same chip as the main switching element 1 and the current sense element 2 or may be externally attached as a resistor element of a discrete component.

<Embodiment 2>
In the first embodiment, the temperature of the main switching element 1 is measured by measuring the length of time that the reverse recovery current flows through the parasitic diode of the current sense element 2, that is, the length of time that the sense voltage Vs is equal to or higher than the predetermined threshold voltage Vs1. Was detected. According to this method, since the specific length of the reverse recovery time is known, the specific temperature value of the main switching element 1 can also be known.

  However, in actual use, it is almost always sufficient to determine whether or not the temperature of the main switching element 1 exceeds the rated temperature (the maximum temperature at which normal operation of the main switching element 1 is guaranteed). That is, it is only necessary to detect whether or not the measured reverse recovery time is longer than the reverse recovery time at the rated temperature.

  Therefore, in the second embodiment, a simpler temperature detection method is proposed. Here, the temperature detection of the main switching element 1 in the lower switching device 10b of the inverter shown in FIGS. 4 and 5 will be described as an example.

  As shown in FIG. 12, the reverse recovery time detection circuit 5 of the present embodiment detects the sense voltage Vs only at time tD after a certain delay time from time t3 when the lower switching device 10b is turned on. Compared with a predetermined threshold voltage Vs2, it is determined whether or not the sense voltage Vs exceeds the threshold voltage Vs2. The threshold voltage Vs2 is set in advance to the value of the sense voltage Vs at time tD when the main switching element 1 is at the rated temperature.

  For example, if the sense voltage Vs after time tD is greater than the threshold voltage Vs2, it can be seen that the reverse recovery time is longer than that at the rated temperature, and it can be determined that the main switching element 1 exceeds the rated temperature. Conversely, if the sense voltage Vs after time tD is equal to or lower than the threshold voltage Vs2, it can be seen that the reverse recovery time is shorter than that at the rated temperature, and it can be determined that the main switching element 1 is equal to or lower than the rated temperature.

  As described above, in the present embodiment, the reverse recovery time detection circuit 5 detects only whether or not the reverse recovery time is longer than that at the rated temperature, so that the specific temperature of the main switching element 1 cannot be detected. However, it is possible to determine whether or not at least the temperature of the main switching element 1 exceeds the rated value. According to the present embodiment, since the reverse recovery time detection circuit 5 does not need to measure time, the reverse recovery time detection circuit 5 can be configured with a simple circuit as compared with the first embodiment, and the semiconductor device according to the present invention. Can contribute to cost reduction.

<Embodiment 3>
As described above, the current detection by the current detection circuit 4 needs to be performed during a period in which no reverse recovery current flows through the parasitic diode of the current sense element 2. Therefore, the current detection is desirably started from time tDs after the period in which the reverse recovery current flows as shown in FIG.

  Since the time during which the reverse recovery current flows varies depending on the temperature, when fixing the timing of the current detection start time tDs, it is necessary to secure a certain margin period with respect to the period in which the reverse recovery current is expected to be zero. is there. Increasing the margin period can prevent erroneous detection of current, but delays the current detection start timing. Therefore, in the third embodiment, the time tDs at which the current detection is started is controlled according to the temperature at that time, that is, the measurement result of the reverse recovery time.

  As can be seen from the graph of FIG. 10, the length of the period during which the reverse recovery current flows through the parasitic diode of the current sensing element 2 increases as the temperature increases. Therefore, in the present embodiment, the delay time from the time t3 when the switching device 10 is turned on to the time tDs when the current detection is started is longer when the temperature is high (when the reverse recovery time is long) and when the temperature is low (reverse recovery time). Shorter when it is short).

  In the inverter circuit as shown in FIG. 4 and FIG. 5, the driving signal of each switching device is a rectangular wave-like repetitive signal. Therefore, the control of the time tDs at which the current detection is started may be performed based on the temperature detection result one cycle before the drive signal, that is, the previous reverse recovery time measurement result.

  According to the present embodiment, the reverse recovery time detection circuit 5 can perform accurate current detection that is not affected by the reverse recovery current while minimizing the delay of the current detection start timing.

  1 main switching element, 2 current sense element, 3 sense resistor, 4 current detection circuit, 5 reverse recovery time detection circuit, 10 switching device, SE sense voltage terminal.

Claims (11)

A main switching element;
A series circuit of a current sensing element and a resistance element for current detection, which is connected in parallel to the main switching element, and a current flowing smaller than the main switching element is set,
Based on the voltage of the sense terminal connected between the current sense element and the resistance element, the reverse recovery time, which is the time when the reverse recovery current flows through the parasitic diode of the current sense element , the main switching element is rated temperature And a reverse recovery time detection circuit that detects whether or not the reverse recovery time is longer than the reverse recovery time and determines whether or not the temperature of the main switching element exceeds a rated value based on the detection result. ,
The reverse recovery time detection circuit compares the voltage of the sense terminal at a predetermined timing immediately after turn-on of the main switching element with a predetermined threshold, so that the reverse recovery time is when the main switching element is at a rated temperature. Detecting whether it is longer than the reverse recovery time ,
The semiconductor device according to claim 1, wherein the predetermined threshold value is equal to a voltage of the sense terminal at the predetermined timing when the main switching element is at a rated temperature. A main switching element;
A series circuit of a current sensing element and a resistance element for current detection, which is connected in parallel to the main switching element, and a current flowing smaller than the main switching element is set,
Based on the voltage of the sense terminal connected between the current sense element and the resistance element, the reverse recovery time, which is the time when the reverse recovery current flows through the parasitic diode of the current sense element, is measured, and based on the measured value And a reverse recovery time detection circuit for detecting the temperature of the main switching element,
The detection of the main current by the current detection circuit and the detection of the reverse recovery time by the reverse recovery time detection circuit are performed in different periods.
A semiconductor device. The reverse recovery time detection circuit
The reverse recovery time is detected by measuring the time when the voltage at the sense terminal exceeds a predetermined threshold within a predetermined period immediately after the main switching element is turned on.
The semiconductor device according to claim 2. The lifetime of the main switching element is shorter than the lifetime of the current sensing element.
The semiconductor device according to claim 1. The main switching element has a shortened lifetime by any one of electron beam irradiation, ion irradiation and radiation irradiation.
The semiconductor device according to claim 4. The current sense element is set so that a current of 1/5000 to 1/10000 of a current flowing through the main switching element flows.
The semiconductor device according to claim 1. A current detection circuit for detecting a main current flowing through the main switching element based on the voltage of the sense terminal;
The semiconductor device according to claim 1. The main switching element and the current sensing element are formed on the same semiconductor chip.
The semiconductor device according to claim 1. The current sense element is disposed at a central portion of the semiconductor chip.
The semiconductor device according to claim 8. The semiconductor device according to claim 1, wherein the main switching element and the current sense element are formed using silicon carbide. A driving circuit configured using the semiconductor device according to claim 1 and driving an inductive load.

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