JP2018082420A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device for driving a power semiconductor device capable of cutting off the power semiconductor device with certainty in a case where a control signal for cutting off the power semiconductor device is inputted to the semiconductor device.SOLUTION: A semiconductor device comprises: a power semiconductor element connected between a high-potential side first terminal and a low-potential side second terminal, and on/off-controlled depending on its gate potential; a cut-off condition detector that detects whether or not a control signal inputted from a control terminal and controlling the power semiconductor element satisfies a preliminarily defined cut-off condition; and a cut-off circuit that controls the gate potential of the power semiconductor element to an off potential in response to that the cut-off condition detector detects that the cut-off condition is satisfied. The cut-off condition detector has an input terminal connected with the first terminal and the control terminal, and uses an electric signal inputted from the input terminal as a power supply.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a semiconductor device.

Conventionally, a power semiconductor device that handles large power has been known as a semiconductor device used for ignition of an internal combustion engine (see, for example, Patent Document 1). It is desirable that such a circuit for driving a power semiconductor device can prevent a malfunction that would cause the power semiconductor device to be turned on despite receiving a shut-off signal for turning the power semiconductor device off.
Japanese Patent Application Laid-Open No. 2009-284420

  When such a power semiconductor device drive circuit continues to operate in an abnormal state due to a malfunction, not only the drive circuit but also an internal combustion engine or the like connected to the drive circuit may cause problems. May end up. Therefore, it is desired that the drive circuit has a function of reliably shutting off the power semiconductor device when a shut-off signal is input.

  In the first aspect of the present invention, a power semiconductor element connected between the first terminal on the high potential side and the second terminal on the low potential side and controlled to be turned on or off according to the gate potential, and the control terminal And a control signal for controlling the power semiconductor element is detected when the control signal for controlling the power semiconductor element satisfies a predetermined shut-off condition, and the detection of the shut-off condition detector satisfying the shut-off condition. An interrupting circuit for controlling the gate potential of the power semiconductor element to an off potential, and the shutoff condition detecting unit has an input terminal connected to the first terminal and the control terminal, and an electric signal input from the input terminal Is provided as a power source.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

The structural example of the ignition device 1000 which concerns on this embodiment is shown. 2 shows a first example of operation waveforms of respective parts of the semiconductor device 100 according to the present embodiment. The structural example of the ignition device 2000 which concerns on this embodiment is shown. The structural example of the detection part 132 which concerns on this embodiment is shown. An example of the operation waveform of each part of the detection part 132 which concerns on this embodiment is shown. An example of an operation waveform of each part of the semiconductor device 200 according to the present embodiment is shown. The 1st modification of the ignition device 2000 which concerns on this embodiment is shown. 2 shows a second example of the operation waveform of each part of the semiconductor device 100 according to the present embodiment. An example of the waveform which expanded the 2nd example of the operation | movement waveform shown in FIG. 8 is shown. The 2nd modification of the ignition device 2000 which concerns on this embodiment is shown. An example of the operation waveform of each part of the semiconductor device 200 of the second modification is shown. The 3rd modification of the ignition device 2000 which concerns on this embodiment is shown. An example of the operation waveform of each part of the semiconductor device 200 of the 3rd modification is shown.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 shows a configuration example of an ignition device 1000 according to the present embodiment. The ignition device 1000 ignites a spark plug used in an internal combustion engine such as an automobile. In the present embodiment, an example in which the ignition device 1000 is mounted on an automobile engine will be described. The ignition device 1000 includes a control signal generation unit 10, an ignition plug 20, an ignition coil 30, a power supply 40, and a semiconductor device 100.

  The control signal generator 10 generates a switching control signal that controls switching of the semiconductor device 100 between on and off. The control signal generator 10 is, for example, a part or all of an automobile engine control unit (ECU) in which the ignition device 1000 is mounted. The control signal generator 10 supplies the generated control signal to the semiconductor device 100. When the control signal generator 10 supplies the control signal to the semiconductor device 100, the ignition device 1000 starts the ignition operation of the spark plug 20.

  The spark plug 20 generates a spark electrically by discharging. The spark plug 20 is discharged by an applied voltage of about 10 kV or more, for example. As an example, the spark plug 20 is provided in an internal combustion engine, and in this case, ignites a combustion gas such as an air-fuel mixture in a combustion chamber. The spark plug 20 is provided, for example, in a through hole that penetrates from the outside of the cylinder to the combustion chamber inside the cylinder, and is fixed so as to seal the through hole. In this case, one end of the spark plug 20 is exposed in the combustion chamber, and the other end receives an electrical signal from the outside of the cylinder.

  The ignition coil 30 supplies an electrical signal to the spark plug 20. The ignition coil 30 supplies a high voltage for discharging the spark plug 20 as an electrical signal. The ignition coil 30 may function as a transformer, for example, an ignition coil having a primary coil 32 and a secondary coil 34. One end of the primary coil 32 and the secondary coil 34 is electrically connected. The primary coil 32 has fewer windings than the secondary coil 34 and shares a core with the secondary coil 34. The secondary coil 34 generates an electromotive force (mutually induced electromotive force) according to the electromotive force generated in the primary coil 32. The other end of the secondary coil 34 is connected to the spark plug 20, and the generated electromotive force is supplied to the spark plug 20 to be discharged.

  The power source 40 supplies a voltage to the ignition coil 30. The power source 40 supplies a predetermined constant voltage Vb (for example, 14 V) to one end of the primary coil 32 and the secondary coil 34, for example. The power source 40 is, for example, a car battery.

  The semiconductor device 100 switches conduction (on) and non-conduction (off) between the other end of the primary coil 32 of the ignition coil 30 and the reference potential in accordance with a control signal supplied from the control signal generator 10. The semiconductor device 100, for example, conducts between the primary coil 32 and the reference potential in response to the control signal being at a high potential (on potential) and responds to being in the low potential (off potential). 32 and the reference potential are made non-conductive.

  Here, the reference potential may be a reference potential in an automobile control system, or may be a reference potential corresponding to the semiconductor device 100 in the automobile. The reference potential may be a low potential that turns off the semiconductor device 100, and is 0 V as an example. The semiconductor device 100 includes a control terminal 102, a first terminal 104, a second terminal 106, a power semiconductor element 110, a cutoff circuit 120, a cutoff condition detection unit 130, a resistor 150, a resistor 160, and a Zener diode. 170.

  The control terminal 102 inputs a control signal for controlling the power semiconductor element 110. The control terminal 102 is connected to the control signal generator 10 and receives a control signal. The first terminal 104 is connected to the power source 40 via the ignition coil 30. The second terminal 106 is connected to a reference potential. That is, the first terminal 104 is a terminal on the high potential side compared to the second terminal 106, and the second terminal 106 is a terminal on the low potential side compared to the first terminal 104.

  The power semiconductor element 110 has a gate potential controlled according to a control signal. The power semiconductor element 110 includes a gate terminal (G), a collector terminal (C), and an emitter terminal (E), and electrically connects between the collector terminal and the emitter terminal according to a control signal input to the gate terminal. Or cut. The power semiconductor element 110 is connected between the first terminal 104 on the high potential side and the second terminal 106 on the low potential side, and is controlled to be turned on or off according to the gate potential. As an example, the power semiconductor element 110 is an insulated gate bipolar transistor (IGBT). Further, the power semiconductor element 110 may be a MOSFET.

  As an example, the power semiconductor element 110 has a withstand voltage of several hundred volts. The power semiconductor element 110 is, for example, a vertical device in which a collector electrode is formed on the first surface side of the substrate and a gate electrode and an emitter electrode are formed on the second surface side opposite to the first surface. Further, the power semiconductor element 110 may be a vertical MOSFET. As an example, the emitter terminal of the power semiconductor element 110 is connected to a reference potential. The collector terminal is connected to the other end of the primary coil 32. In the present embodiment, an example in which the power semiconductor element 110 is an n-channel IGBT that electrically connects the collector terminal and the emitter terminal in response to the control signal being turned on will be described.

  The cutoff circuit 120 is connected between the gate terminal of the power semiconductor element 110 and the reference potential. As an example, the cutoff circuit 120 is an FET that is controlled to be turned on or off between the drain terminal and the source terminal in accordance with the gate potential. The cutoff circuit 120 has a drain terminal connected to the gate terminal of the power semiconductor element 110, a source terminal connected to the reference potential, and whether to supply a control signal input from the control terminal 102 to the gate terminal of the power semiconductor element 110. Switch.

  In other words, in the cutoff circuit 120, the drain terminal is connected to the gate terminal of the power semiconductor element 110, the source terminal is connected to the emitter terminal of the power semiconductor element 110, and the gate terminal and the emitter terminal of the power semiconductor element 110 are electrically connected. The connection is made to switch whether or not the gate of the power semiconductor element 110 is turned off. For example, the cutoff circuit 120 is a normally-off switch element that electrically connects the drain terminal and the source terminal in response to the gate terminal becoming a high potential. In this case, the cutoff circuit 120 is preferably an n-channel MOSFET.

  The blocking condition detection unit 130 detects whether or not a control signal that is input from the control terminal 102 and controls the power semiconductor element 110 satisfies a predetermined blocking condition. The blocking condition detection unit 130 may detect whether or not the blocking signal satisfies the blocking condition using a predetermined threshold value. The blocking condition detection unit 130 includes a detection unit 132 and a signal output unit 134.

  The detection unit 132 detects whether or not the control signal exceeds a predetermined threshold value. For example, it is assumed that the detection unit 132 satisfies the blocking condition in response to the control signal Vin for turning on the power semiconductor element 110 being smaller than the threshold value Vthin (for example, 2V). The detection unit 132 supplies the detection result to the signal output unit 134.

  The signal output unit 134 outputs a cutoff circuit control signal for controlling the cutoff circuit 120 according to the detection result of the detection unit 132. The signal output unit 134 outputs a cut-off circuit control signal for turning on the cut-off circuit 120 in accordance with a detection result of detecting that the control signal satisfies the cut-off condition. Further, the signal output unit 134 outputs a cutoff circuit control signal that turns off the cutoff circuit 120 in accordance with a detection result that the control signal does not satisfy the cutoff condition.

  The signal output unit 134 is an inverter as an example. The signal output unit 134 operates using the electrical signal input from the first terminal 104 as a power source, and inverts and outputs the detection result of the detection unit 132. The signal output unit 134 is connected to the cutoff circuit 120 and supplies a cutoff circuit control signal to the cutoff circuit 120. That is, the cutoff circuit 120 controls the gate potential of the power semiconductor element 110 to the off potential in response to the detection of the cutoff condition detection unit 130 that satisfies the cutoff condition.

  The resistor 150 is provided between the first terminal 104 and the power terminal on the high potential side of the signal output unit 134, and supplies an electric signal input from the first terminal 104 to the signal output unit 134 as a power source. Note that the electrical signal input from the first terminal 104 varies depending on whether the power semiconductor element 110 is on or off. Therefore, the resistor 150 limits the current input to the signal output unit 134 from the first terminal 104 side. For example, the resistor 150 is a protective resistor that reduces the current input to the signal output unit 134 from the first terminal 104 side to a predetermined current value or less even when the collector voltage of the power semiconductor element 110 rises to about 400V. Works as.

  The resistor 160 is connected between the control terminal 102 and the gate terminal of the power semiconductor element 110. The resistor 160 transmits a control signal to the gate terminal of the power semiconductor element 110 when the cutoff circuit 120 is in an off state. The resistor 160 causes the control signal to drop when the control signal is supplied to the reference potential while the cutoff circuit 120 is on. That is, the reference potential is supplied to the gate terminal of the power semiconductor element 110.

  Zener diode 170 is connected between resistor 150 and a reference potential. The Zener diode 170 prevents a voltage exceeding the rating of the signal output unit 134 from being input from the first terminal 104. For example, the Zener diode 170 clamps the voltage input to the signal output unit 134 from the first terminal 104 side to a predetermined voltage value even when the collector voltage of the power semiconductor element 110 rises to about 400V. For example, the Zener diode 170 is clamped to about 6V to 16V.

  In the semiconductor device 100 according to the above-described embodiment, when the control signal becomes a high potential, the power semiconductor element 110 is turned on. As a result, the collector current Ic flows from the power source 40 through the primary coil 32 of the ignition coil 30. The time change dIc / dt of the collector current Ic is determined according to the inductance of the primary coil 32 and the supply voltage of the power supply 40, and increases to a predetermined (or set) current value. For example, the collector current Ic increases to several A, several tens of A, or several tens of A.

  When the control signal becomes a low potential, the power semiconductor element 110 is turned off, and the collector current rapidly decreases. Due to the rapid decrease of the collector current, the voltage across the primary coil 32 increases rapidly due to the self-induced electromotive force, and an induced electromotive force reaching about several tens of kV is generated at both ends of the secondary coil 34. The ignition device 1000 can ignite the combustion gas by discharging the ignition plug 20 by supplying the voltage of the secondary coil 34 to the ignition plug 20.

  FIG. 2 shows a first example of operation waveforms of each part of the semiconductor device 100 according to the present embodiment. In FIG. 2, the horizontal axis represents time, and the vertical axis represents voltage value or current value. In FIG. 2, the control signal input from the control terminal 102 is “Vin”, the detection signal output from the detection unit 132 is “Vt”, the cutoff circuit control signal output from the signal output unit 134 is “Vs”, and the power semiconductor. The potential of the gate terminal of the element 110 is “Vg”, the collector-emitter current (collector current) of the power semiconductor element 110 is “Ic”, and the collector-emitter voltage (collector voltage) of the power semiconductor element 110 is Each time waveform is shown as “Vc”.

  FIG. 2 shows an example of a triangular wave shape in which the control signal Vin input to the control terminal 102 rises linearly from 0V to a voltage exceeding the threshold value Vthin of the detection unit 132, and then falls linearly from 0% to the voltage exceeding the threshold value Vthin. Show. FIG. 2 shows operation waveforms of the respective parts with respect to the control signal Vin having the triangular wave shape.

  The detection unit 132 may use a control signal input from the control terminal 102 as an operation voltage. In this case, the detection unit 132 performs a detection operation in response to input of a control signal exceeding the threshold value V1. Therefore, when the control signal does not exceed the threshold value V1, the detection unit 132 outputs the input signal as it is. That is, the detection unit 132 outputs substantially the same potential as the control signal Vin until the control signal Vin exceeds the threshold value V1. FIG. 2 shows an example in which the detection signal Vt of the detection unit 132 has an output waveform that is substantially the same as that of the control signal Vin after the time t1 and after the time t4.

  In addition, when Vin is a potential that exceeds the threshold value V1 and is equal to or less than the threshold value Vthin, the detection unit 132 outputs a low potential, assuming that the blocking condition is satisfied. FIG. 2 shows an example in which the detection signal Vt of the detection unit 132 becomes a low potential between the times t1 and t2 and between the times t3 and t4. In addition, when Vin exceeds the threshold value Vthin, the detection unit 132 outputs a high potential because the cutoff condition is not satisfied. Note that the detection unit 132 may output substantially the same potential as the control signal Vin as a high potential. FIG. 2 shows an example in which the detection signal Vt of the detection unit 132 has substantially the same output waveform as that of the control signal Vin from time t2 to time t3.

  Since the signal output unit 134 operates using the electric signal input from the first terminal 104 as a power supply, when outputting a high potential, the signal output unit 134 outputs a smaller potential of the collector voltage Vc and the breakdown voltage Vzd of the Zener diode 170. For example, when the detection signal Vt is a low potential, the signal output unit 134 outputs such a high potential as an inverted signal of the low potential. FIG. 2 shows an example in which the cutoff circuit control signal Vs of the signal output unit 134 outputs substantially the same potential as the breakdown voltage Vzd until time t2.

  Further, the signal output unit 134 outputs a low potential that is an inverted signal of the high potential in response to the detection signal Vt becoming a high potential. FIG. 2 shows an example in which the cutoff circuit control signal Vs of the signal output unit 134 becomes a low potential from time t2 to t3.

  Since the detection signal Vt becomes a low potential from time t3 to t4, the signal output unit 134 outputs a high potential again. However, since the control signal Vin is in a range of potential greater than the threshold value Vthi of the power semiconductor element 110, the power semiconductor element 110 continues to be in the on state, and the collector voltage Vc becomes the potential Vcl when the power semiconductor element 110 is on. . Since the potential Vcl is lower than the breakdown voltage Vzd of the Zener diode 170, as shown in the example of FIG. 2, the cutoff circuit control signal Vs of the signal output unit 134 is applied to the collector terminal from time t3 to t4. A potential substantially the same as the on-state potential Vcl is output.

  When the time t4 is exceeded, the detection signal Vt becomes a low potential, and the control signal Vin is in a potential range smaller than the threshold value Vthi of the power semiconductor element 110, so that the power semiconductor element 110 is switched to the off state, and the collector The voltage Vc is substantially the same as the constant voltage Vb supplied from the power source 40. Therefore, as shown in the example of FIG. 2, when the time t4 is exceeded, the cutoff circuit control signal Vs of the signal output unit 134 becomes a high potential substantially the same as the breakdown voltage Vzd.

  The potential Vg of the gate terminal of the power semiconductor element 110 becomes a low potential when the cutoff circuit control signal Vs is a high potential exceeding the threshold value of the cutoff circuit 120. The potential Vg is substantially the same potential as the control signal Vin when the cutoff circuit control signal Vs is a low potential that is equal to or lower than the threshold value of the cutoff circuit 120. FIG. 2 shows an example in which Vg becomes low potential until time t2 and exceeds time t4, and becomes substantially the same potential as the control signal Vin from time t2 to time t4.

  The power semiconductor element 110 operates according to such a potential Vg of the gate terminal. That is, in the example of FIG. 2, the power semiconductor element 110 is turned on from the time t2 to the time t4, and is turned off during the period up to the time t2 and the period exceeding the time t4.

  That is, the collector current Ic of the power semiconductor element 110 becomes substantially zero (off) until Vg exceeds Vthin, and flows (on) in response to Vg being a potential exceeding Vthin, and its maximum value is (Vb -Vbi) / (Rl + Ron). Here, Vb is a constant voltage supplied by the power supply 40, Vbi is a built-in potential of the power semiconductor element 110, Rl is a resistance of the primary coil 32, and Ron is an on-resistance of the power semiconductor element 110. FIG. 2 shows an example in which the collector current Ic is turned off in the period up to the time t2 and in the period exceeding the time t4, and becomes (Vb−Vbi) / (Rl + Ron) from the time t2 to the time t4.

  The collector voltage Vc of the power semiconductor element 110 becomes a high potential until Vg exceeds Vthin, and becomes a low potential in response to Vg being a potential exceeding Vthin. FIG. 2 shows an example in which Vc becomes a low potential at time t2 and becomes a high potential at time t4.

  Here, in the semiconductor device 100 shown in FIG. 1, the collector voltage Vc is substantially equal to the constant voltage Vb supplied by the power supply 40 in a state where the power semiconductor element 110 is turned off. In this case, the signal output unit 134 outputs a potential substantially equal to Vb with the breakdown voltage of the Zener diode 170 as an upper limit. When Vb is larger than the threshold value of the cutoff circuit 120 (for example, 1.1V), the cutoff circuit 120 blocks the power semiconductor element 110. In the present embodiment, the constant voltage Vb is 14 V as an example, and therefore the collector voltage Vc becomes substantially the same potential as the constant voltage Vb in the period up to the time t2 and the period exceeding the time t4.

  In the state where the power semiconductor element 110 is on, the collector voltage Vc is Vb, the built-in potential Vbi of the power semiconductor element 110, the on-resistance Ron of the power semiconductor element 110, the resistance Rl of the primary coil 32, Vc = (Vb−Vbi) × Ron / (Ron + Rl) + Vbi. For example, if Vbi = 0.6V, Ron = 50 mΩ, and Rl = 0.6Ω, then Vc = 1.63V when Vb = 14V, and Vc = 1.02V when Vb = 6V.

  That is, when the detection unit 132 detects a cutoff condition with the power semiconductor element 110 turned on, if Vb = 14V, the cutoff circuit 120 shuts off the power semiconductor element 110, but if Vb = 6V, the cutoff circuit 120 shuts off. Can not. In the present embodiment, the constant voltage Vb is 14 V as an example, and therefore the collector voltage Vc is substantially the same as Vcl = 1.63 V in the period between time t2 and time t4.

  As described above, it can be seen that the semiconductor device 100 keeps the power semiconductor element 110 in the on state between the times t3 and t4 even if the control signal Vin satisfies the cutoff condition. If such a malfunction occurs and the operation is continued in the malfunctioned state, the power semiconductor element 110 or the like may break down. In addition, not only the failure of the power semiconductor element 110 and the like, but also a failure or the like may occur in the internal combustion engine or the like connected to the power semiconductor element 110.

  Note that the power semiconductor element 110 has a smaller loss as the threshold value Vthi becomes smaller, which is advantageous as a switch, and thus conflicts with the occurrence of malfunction. Therefore, the semiconductor device 200 according to the present embodiment does not depend on the value of the threshold value Vthi, and even when the power semiconductor element 110 is turned on, the control signal Vin satisfies the cutoff condition. The power semiconductor element 110 is reliably cut off to prevent malfunction.

  FIG. 3 shows a configuration example of the ignition device 2000 according to the present embodiment. In the ignition device 2000 shown in FIG. 3, substantially the same operations as those of the ignition device 2000 according to the present embodiment shown in FIG. The ignition device 2000 includes a semiconductor device 200. Note that description of the control signal generator 10, the ignition plug 20, the ignition coil 30, and the power supply 40 included in the ignition device 2000 is omitted.

  The semiconductor device 200 includes a control terminal 202, a first terminal 204, a second terminal 206, a power semiconductor element 110, a cutoff circuit 120, a cutoff condition detection unit 130, a resistor 150, a resistor 160, and a Zener diode. 170, a first rectifying element 210, and a second rectifying element 220.

  The control terminal 202 inputs a control signal for controlling the power semiconductor element 110. The control terminal 202 is connected to the control signal generator 10 and receives a control signal. The first terminal 204 is connected to the power supply 40 via the ignition coil 30. The second terminal 206 is connected to a reference potential. That is, the first terminal 204 is a terminal on the high potential side compared to the second terminal 206, and the second terminal 206 is a terminal on the low potential side compared to the first terminal 204.

  The power semiconductor element 110, the cutoff circuit 120, the resistor 150, the resistor 160, and the Zener diode 170 have been described with reference to FIG.

  The interruption condition detection unit 130 has an input terminal 140 connected to the first terminal 204 and the control terminal 202, and uses an electric signal input from the input terminal 140 as a power source. That is, the interruption condition detection unit 130 uses two signals, that is, an electric signal from the first terminal 204 and a control signal from the control terminal 202 as a power source. Thereby, when the signal voltage of the electrical signal from the first terminal 204 decreases, the signal output unit 134 can compensate for the signal voltage of the electrical signal from the control terminal 202, and a stable power supply voltage can be supplied to the input terminal 140. Can be received from.

  The first rectifying element 210 is connected between the control terminal 202 and the input terminal 140 of the cutoff condition detection unit 130. The first rectifying element 210 supplies a control signal input from the control terminal 202 to the signal output unit 134 and suppresses an electrical signal that flows back to the control terminal 202. As a result, the signal output unit 134 receives power supply from the control terminal 202 that inputs a control signal for controlling the power semiconductor element 110 via the first rectifying element 210. For example, when a high potential of about 5 V is input from the control terminal 202 as the control signal, the first rectifier element 210 supplies a potential of about 4.4 V to the signal output unit 134. Here, the threshold value Vf of the first rectifying element 210 is set to about 0.6V. As an example, the first rectifying element 210 is a diode.

  The second rectifying element 220 is connected between the first terminal 204 and the input terminal 140 of the cutoff condition detection unit 130. The second rectifying element 220 may be connected between the resistor 150 and the signal output unit 134, and supplies the potential of the first terminal 204 to the signal output unit 134 via the resistor 150 and to the first terminal 204. Suppresses backflowing electrical signals. As a result, the signal output unit 134 receives power supply from the first terminal 204 via the second rectifying element 220.

  For example, when the breakdown voltage Vzd of the Zener diode 170 is about 6V, the second rectifying element 220 supplies a potential of about 5.4V to the signal output unit 134 on the condition that the collector voltage Vc is 6V or more. . Here, the threshold value Vf of the second rectifying element 220 is set to about 0.6V. The second rectifying element 220 is, for example, a diode.

  In this case, a resistor 150 is connected between the first terminal 204 and the second rectifying element 220. The resistor 150 may be any element having a resistance that limits the current input from the first terminal 104 side to the signal output unit 134 via the input terminal 140, and is not limited to the resistor element.

  In the semiconductor device 200 according to the present embodiment described above, the power semiconductor element 110 is turned on when the control signal becomes a high potential, similarly to the semiconductor device 100 described in FIG. Accordingly, as described with reference to FIG. 1, the ignition device 2000 can ignite the combustion gas by discharging the spark plug 20.

  When the control signal changes from a high potential to a low potential, the signal output unit 134 first outputs a potential of about 4.4 V, and starts shutting off the power semiconductor element 110. When Vc> Vin is established after the start of the shutoff, the output potential of the signal output unit 134 becomes Vc−Vf, and the power semiconductor element 110 is kept shut off. That is, since either the control terminal 202 or the collector voltage is higher than the high potential, the signal output unit 134 can prevent the power semiconductor element 110 from malfunctioning without running out of the power supply voltage. Details of each part of the ignition device 2000 will be described below.

  FIG. 4 shows a configuration example of the detection unit 132 according to the present embodiment. The detection unit 132 includes a control signal input unit 302, a detection signal output unit 304, a reference potential input unit 306, a resistor 310, a resistor 320, an inverter 330, and an inverter 340.

  The control signal input unit 302 inputs a control signal input from the control terminal 202. The detection unit 132 operates using the control signal as a power source. The detection signal output unit 304 outputs the detection result of the detection unit 132. As an example, the detection signal output unit 304 is connected to the signal output unit 134, and outputs a potential having the same logic as that of the control signal as a detection result of the control signal. The reference potential input unit 306 is connected to the reference potential.

  The resistor 310 and the resistor 320 are connected in series between the control signal input unit 302 and the reference potential input unit 306, and divide the control signal Vin input from the control signal input unit 302. Here, the divided potential that is divided and output by the resistor 310 and the resistor 320 is a potential between the resistor 310 and the resistor 320. For example, when the resistance value of the resistor 310 is R1 and the resistance value of the resistor 320 is R2, the divided potential is Vin · R2 / (R1 + R2). As an example, when the control signal transiently rises linearly from an off potential (0 V as an example) to an on potential (5 V as an example), the divided potential also rises linearly from 0 V to 5 · R2 / (R1 + R2). .

  The inverter 330 has an input terminal connected between the resistor 310 and the resistor 320, receives the divided potential, and outputs a signal obtained by inverting the logic from the output terminal. The inverter 340 receives the output signal of the inverter 330 and outputs a signal obtained by inverting the logic.

  Note that each of the inverter 330 and the inverter 340 uses a control signal input from the control signal input unit 302 as an operation power supply. Therefore, each inverter outputs a signal having substantially the same potential as the control signal until the control signal reaches the threshold value of the inverter in the process where the control signal rises transiently. In this example, the threshold value of each inverter is set to substantially the same value V1. The operation of each part of the detection unit 132 will be described with reference to FIG.

  FIG. 5 shows an example of the operation waveform of each part of the detection unit 132 according to the present embodiment. In FIG. 5, the horizontal axis represents time, and the vertical axis represents output potential. FIG. 5 shows an example of output potentials of the inverter 330 and the inverter 340 when the control signal Vin input to the control signal input unit 302 rises linearly from the off potential (0 V) to the on potential (5 V). The output potential Vout1 of the inverter 330 and the output potential Vout2 of the inverter 340 are substantially the same as the power supply potential (that is, the control signal Vin) until the input potential reaches the inverter threshold value V1.

  In the inverter 330, even if the potential of the power supply exceeds the threshold value V1, since the divided potential Vin / R2 / (R1 + R2) to be input is a value equal to or lower than the threshold value V1, the input potential becomes a low potential and the inverted output becomes a high potential. Note that even if the inverter 330 operates to output a high potential, if the power supply potential is a transient potential in the process of reaching a high potential (for example, 5 V), the inverter 330 outputs the power supply potential as a high potential. FIG. 5 shows an example in which the output potential Vout1 of the inverter 330 outputs substantially the same potential as the power supply potential Vin after time t1.

  The inverter 330 inverts the low potential according to the fact that the potential of the power source exceeds the threshold value V1 and the divided potential to be input exceeds the threshold value V1 (that is, input of a high potential). FIG. 5 shows an example in which the output potential Vout1 of the inverter 330 becomes a low potential (0 V) at time t2.

  The inverter 340 outputs the low potential as an inverted output in response to the potential of the power source exceeding the threshold V1 and the input potential exceeding the threshold V1. FIG. 5 shows an example in which the output potential Vout2 of the inverter 340 becomes a low potential at time t1. The inverter 340 outputs the high potential as an inverted output in response to the potential of the power source exceeding the threshold value V1 and the input potential being the low potential. Note that the inverter 340 outputs the power supply potential as a high potential when the power supply potential is a transient potential in the process of reaching the high potential. FIG. 5 shows an example in which the output potential Vout2 of the inverter 340 becomes substantially the same potential as the power supply potential Vin after the time t2.

  The detection unit 132 outputs the output potential Vout2 of the inverter 340 from the detection signal output unit 304 as a detection signal. And the signal output part 134 controls the interruption | blocking circuit 120 according to the said detection signal, using the electrical signal input from the 1st terminal 204 and the control terminal 202 as a power supply. As a result, the semiconductor device 200 according to the present embodiment operates as an igniter that controls the current flowing through the ignition coil 30 in accordance with an external control signal. The operation of the semiconductor device 200 will be described with reference to FIG.

  FIG. 6 shows an example of the operation waveform of each part of the semiconductor device 200 according to the present embodiment. In FIG. 6, the horizontal axis represents time and the vertical axis represents voltage value or current value. In FIG. 6, the control signal input from the control terminal 202 is “Vin”, the detection signal output from the detection unit 132 is “Vt”, the cutoff circuit control signal output from the signal output unit 134 is “Vs”, and the power semiconductor. The potential of the gate terminal of the element 110 is “Vg”, the collector-emitter current (collector current) of the power semiconductor element 110 is “Ic”, and the collector-emitter voltage (collector voltage) of the power semiconductor element 110 is Each time waveform is shown as “Vc”.

  The time waveform of the detection signal Vt of the detection unit 132 is substantially the same as the output potential Vout2 of the inverter 340 described with reference to FIG. Further, the detection signal Vt of the detection unit 132 is substantially the same as the time waveform Vt of the detection unit 132 of the semiconductor device 100 shown in FIG.

  Since the signal output unit 134 is an inverted output of the detection signal Vt, the signal output unit 134 operates to output a high potential until time t2. In this case, as described with reference to FIG. 2, the potential input from the first terminal 204 to the input terminal 140 is the second potential from the smaller potential of the collector voltage Vc of the power semiconductor element 110 and the breakdown voltage Vzd of the Zener diode 170. This is a potential obtained by subtracting the threshold value Vf of the rectifying element 220. In other words, since the power semiconductor element 110 is in the off state, it becomes Vzd−Vf until time t2. Therefore, since the potential Vzd-Vf is input as the power supply voltage, the signal output unit 134 outputs the cutoff circuit control signal Vs that is substantially the same as the potential Vzd-Vf as in FIG.

  Further, when the time t2 is exceeded, the signal output unit 134 outputs a low potential as an inverted output of the detection signal Vt. Further, when the time t3 is exceeded, the signal output unit 134 operates to output a high potential as an inverted output of the detection signal Vt. In this case, until the potential of the control signal Vin becomes equal to or lower than Vthi after the time t3 is exceeded, the potential input from the first terminal 204 to the input terminal 140 is the time when the collector terminal is on, as described with reference to FIG. Is substantially equal to the potential Vcl. On the other hand, the potential of the control signal Vin input from the control terminal 202 to the input terminal 140 is a potential exceeding Vthi.

  Therefore, since the signal output unit 134 of the present embodiment uses the control signal Vin as a power source, the high potential cutoff circuit control signal Vs of the inverted output is generated in response to the detection signal Vt becoming a low potential at the time t3. Can be output. Accordingly, the cutoff circuit 120 sets the gate of the power semiconductor element 110 to the off potential, so that the power semiconductor element 110 is turned off and the collector voltage becomes Vb. That is, since the potential input from the first terminal 204 to the input terminal 140 is Vzd−Vf, the signal output unit 134 outputs the cutoff circuit control signal Vs substantially the same as the potential Vzd−Vf from time t3. be able to.

  As described above, the cutoff circuit control signal Vs output by the signal output unit 134 becomes a high potential until time t2 and after time t3, as shown in the example of FIG. During this period, the potential is low. In response to such a cutoff circuit control signal Vs, the cutoff circuit 120 controls the gate potential Vg of the power semiconductor element 110, so that the gate potential Vg is from the time t2 to the time t3 as in the example of FIG. The potential is substantially the same as that of the control signal Vin, and the potential is low until time t2 and after time t3 has elapsed.

  Therefore, the power semiconductor element 110 is turned on during the period from time t2 to t3, and is turned off until time t2 and after the time t3 has elapsed. Thereby, as shown in the example of FIG. 6, the collector current Ic is turned off until time t2 and turned on in response to Vg being a potential exceeding Vthin, and the maximum value thereof is (Vb−Vbi) / (Rl + Ron).

  Further, the collector voltage Vc of the power semiconductor element 110 becomes a high potential until the time t2 and after the time t3, and becomes a low potential during the period from the time t2 to the time t3. FIG. 6 shows an example in which the collector voltage Vc becomes a low potential (Vcl) in the period from time t2 to t3, and becomes a high potential (Vb) until time t2 and after the time t3 has elapsed.

  The semiconductor device 200 according to the present embodiment described above can shut off the power semiconductor element 110 by using two power sources even when the control signal Vin is switched from on to off. Therefore, the semiconductor device 200 can reliably shut off the power semiconductor device according to the shut-off signal, and can prevent malfunction.

  In the semiconductor device 200 according to this embodiment described above, the example in which the resistor 150 is connected between the first terminal 204 and the second rectifying element 220 has been described. Instead of this, for example, a switch element may be connected between the first terminal 204 and the second rectifying element 220. FIG. 7 shows a first modification of the ignition device 2000 according to this embodiment. In the ignition device 2000 of this modification, the same reference numerals are given to the substantially same operations as those of the ignition device 2000 according to this embodiment shown in FIG. 3, and the description thereof is omitted.

  The ignition device 2000 of this modification shows an example in which a switch element 350 is connected between the first terminal 204 and the second rectifier element 220. For example, the switch element 350 may be a depletion type MOSFET. In this case, the drain may be connected to the first terminal 204, the source may be connected to the second rectifier element 220, and the gate may be connected to the source. Thereby, even if the collector voltage Vc becomes excessive, the switch element 350 can increase the resistance value between the drain and the source corresponding to the collector voltage Vc. That is, the switch element 350 can limit the current flowing through the second rectifying element 220 to, for example, about 100 μA, and can prevent an excessive current from flowing as the collector voltage Vc increases.

  As described above, it has been described that the semiconductor device 200 according to the present embodiment can shut off the power semiconductor element 110. In addition to this, the semiconductor device 200 can further reduce the transient cutoff time. Good. In order to describe such a semiconductor device 200, first, the transient response of the semiconductor device 100 according to the present embodiment shown in FIG. 1 will be described.

  FIG. 8 shows a second example of the operation waveform of each part of the semiconductor device 100 according to the present embodiment. In FIG. 8, the horizontal axis represents time, and the vertical axis represents voltage value or current value. Further, in FIG. 8, the control signal input from the control terminal 102 is “Vin”, the detection signal output from the detection unit 132 is “Vt”, the cutoff circuit control signal output from the signal output unit 134 is “Vs”, and the power semiconductor The respective time waveforms are shown, assuming that the gate terminal potential of the element 110 is “Vg”, the collector current of the power semiconductor element 110 is “Ic”, and the collector voltage of the power semiconductor element 110 is “Vc”.

  FIG. 8 shows an example of the shape of a rectangular wave in which the control signal Vin is on at time t5 and off at time t7. Note that the amplitude value of the rectangular wave is a voltage exceeding the threshold value Vthin of the detection unit 132. As a result, the detection signal Vt output from the detection unit 132 also has a rectangular wave shape having a high potential at time t5 and a low potential at time t7.

  In response to the detection signal Vt of the detection unit 132, the cutoff circuit control signal Vs becomes a high potential from time t5, a low potential from time t5 to time t7, and a high potential from time t7. Therefore, the gate potential Vg of the power semiconductor element 110 has a rectangular wave shape that is a high potential at time t5 and a low potential at time t7. Thereby, the collector current Ic starts to flow from time t5, and as an example, the collector current Ic is saturated at time t6. Similarly to the collector current Ic, the collector voltage Vc starts to increase from time t5, and reaches the potential Vcl when the power semiconductor element 110 is turned on at time t6.

  At time t7, the gate potential Vg becomes a low potential and the power semiconductor element 110 is turned off, so that the collector current Ic is cut off and the collector voltage Vc increases rapidly, and then becomes equal to the voltage Vb of the power supply 40. Become. Next, a transient operation of the semiconductor device 100 will be described.

  FIG. 9 shows an example of an enlarged waveform of the second example of the operation waveform shown in FIG. FIG. 9 shows an example in which the time before and after the control signal Vin is switched off in FIG. In FIG. 9, the time when the control signal Vin is turned off is changed to time t7a. The detection signal Vt output from the detection unit 132 becomes a low potential at time t7a in accordance with the control signal Vin.

  Transitionally, when the control signal Vin is turned off, the gate potential Vg of the power semiconductor element 110 gradually decreases as shown from time t7a to time t7b. Since the decrease amount of the gate potential Vg is slight, the cutoff circuit control signal Vs, the collector current Ic, and the collector voltage Vc are hardly changed during the period from the time t7a to the time t7b and hold the value at the time t7a.

  When the gate potential Vg of the power semiconductor element 110 decreases, the power semiconductor element 110 eventually pinches off. In this case, the collector voltage Vc starts to increase, a mirror current flows from the collector to the gate, and the decrease in the gate potential Vg stops. In FIG. 9, the period during which the gate potential Vg is maintained at a substantially constant voltage is defined as time t7b to t7c. During the period from the time t7b to the time t7c, the cutoff circuit control signal Vs starts to increase as the collector voltage Vc increases. Further, the collector current Ic hardly changes and maintains the value at time t7a.

  When the collector voltage Vc of the power semiconductor element 110 increases and reaches a certain value, the expansion of the depletion layer between the gate and the collector stops and the mirror current also stops. As a result, the gate potential Vg of the power semiconductor element 110 is lowered to 0V. In FIG. 9, the period during which the gate potential Vg decreases to the threshold value Vthi is defined as the time t7c to t7d. As the gate potential Vg decreases, the cutoff circuit control signal Vs and the collector voltage Vc increase, and the collector current Ic decreases.

  When the gate potential Vg of the power semiconductor element 110 becomes 0V, the cutoff circuit control signal Vs becomes equal to the voltage Vzd, the collector current Ic becomes equal to 0A, and the collector voltage Vc increases rapidly to the voltage Vb. As described above, in the semiconductor device 100, the gate potential Vg becomes transiently lower than the threshold value Vthi after the interruption time from the time t7a when the control signal Vin is turned off to the time t7d has elapsed. Therefore, the semiconductor device 200 according to the present embodiment shortens such a cutoff time.

  FIG. 10 shows a second modification of the ignition device 2000 according to the present embodiment. In the ignition device 2000 of the second modification, the same reference numerals are given to the substantially same operations as those of the ignition device 2000 according to the present embodiment shown in FIG. 3, and the description thereof is omitted. In the semiconductor device 200 of the second modified example, the input terminal 140 of the cutoff condition detection unit 130 is connected to the first terminal 204, the gate terminal of the power semiconductor element 110, and the control terminal 202 via a resistive element. An example is shown.

  That is, in the semiconductor device 200, the input terminal 140 is connected to the first terminal 204 via the second rectifying element 220 and the resistor 150, as in the example of FIG. The input terminal 140 is connected to the gate terminal of the power semiconductor element 110 through the first rectifying element 210. The input terminal 140 is connected to the control terminal 202 via the first rectifying element 210 and a resistive element. That is, the first rectifying element 210 is connected between the resistive element and the input terminal 140, and the first rectifying element 210 is connected between the gate terminal of the power semiconductor element 110 and the input terminal 140. The The resistive element is a resistor or a switch element. FIG. 10 shows an example in which the resistive element is a resistor 160.

  As described above, in the ignition device 2000 of the second modified example, the resistance value between the gate terminal of the power semiconductor element 110 and the input terminal 140 is lower than the resistance value between the control terminal 202 and the input terminal 140. . Therefore, when the voltage at the control terminal 202 becomes 0 V, and the charge and the mirror current transiently charged at the gate flow from the gate terminal to the control terminal 202, the semiconductor device is compared with the semiconductor device 100 shown in FIG. The potential of the 200 input terminals 140 is increased by the voltage drop of the resistor 160.

  That is, even if the collector voltage Vc of the power semiconductor element 110 is a low voltage of about Vcl and the voltage of the control terminal 202 becomes 0V, the mirror current flows, so that the signal output unit 134 causes the voltage drop of the resistor 160. Can be received from the input terminal 140. In this case, the signal output unit 134 can output a voltage corresponding to the resistance value of the resistor 160 as the cutoff circuit control signal Vs. Next, the transient response of the semiconductor device 200 according to the second modification will be described.

  FIG. 11 shows an example of the operation waveform of each part of the semiconductor device 200 of the second modification. FIG. 11 shows an example of an operation waveform when the control signal Vin shown in the operation waveform shown in FIG. 8 is input to the control terminal 202. Note that the horizontal axis and the vertical axis in FIG. 11 are shown with substantially the same scale as the horizontal axis and the vertical axis of the operation waveform shown in FIG. 9.

  That is, the horizontal axis in FIG. 11 represents time, and the vertical axis represents a voltage value or a current value. In FIG. 11, the control signal input from the control terminal 202 is “Vin”, the detection signal output from the detection unit 132 is “Vt”, the cutoff circuit control signal output from the signal output unit 134 is “Vs”, and the power semiconductor. The respective time waveforms are shown, assuming that the gate terminal potential of the element 110 is “Vg”, the collector current of the power semiconductor element 110 is “Ic”, and the collector voltage of the power semiconductor element 110 is “Vc”.

  In FIG. 11, the time when the control signal Vin is turned off is assumed to be t7a. The detection signal Vt output from the detection unit 132 becomes a low potential at time t7a in accordance with the control signal Vin. When the control signal Vin is turned off, the gate potential Vg of the power semiconductor element 110 gradually decreases as shown from time t7a to t7b ′.

  Here, the potential of the input terminal 140 is higher than the potential of the control terminal 202 (that is, 0 V) by the voltage drop of the resistor 160. Therefore, in the period from time t7a to t7b ′, the cutoff circuit control signal Vs can have a voltage value larger than the control signal Vs in the period from time t7a to t7b shown in FIG. In particular, the semiconductor device 200 can make the cutoff circuit control signal Vs during the period from time t7a to t7b ′ larger than the threshold value Vths of the cutoff circuit 120 in accordance with the setting of the resistance value of the resistor 160. As a result, since the cutoff circuit 120 is turned on, the rate at which the gate potential Vg decreases is faster than the rate at which the gate potential Vg shown in FIG. 9 decreases. That is, the time t7b ′ at which the power semiconductor element 110 is pinched off is earlier than the time t7b.

  Similarly to the example of FIG. 9, when the power semiconductor element 110 is pinched off and the collector voltage Vc starts to increase, a mirror current flows from the collector to the gate, and the decrease in the gate potential Vg stops. In FIG. 11, the period during which the gate potential Vg is maintained at a substantially constant voltage is defined as time t7b ′ to t7c ′. In the period from the time t7b ′ to the time t7c ′, the cutoff circuit control signal Vs can continue to be larger than the threshold value Vths, and thus the cutoff circuit 120 holds the on state.

  Thereby, more mirror current from the gate of the power semiconductor element 110 can flow through the cutoff circuit 120, and the increasing speed of the collector voltage Vc is made faster than the increasing speed of the collector voltage Vc shown in FIG. be able to. That is, the period until the mirror current of the power semiconductor element 110 stops (time t7b ′ to t7c ′) is shorter than the period from time t7b to t7c shown in FIG.

  When the mirror current of the power semiconductor element 110 stops, the gate potential Vg decreases to 0V. In FIG. 11, the period during which the gate potential Vg decreases to the threshold value Vthi is set from time t7c ′ to t7d ′. As the gate potential Vg decreases, the cutoff circuit control signal Vs and the collector voltage Vc increase, and the collector current Ic decreases. When the gate potential Vg of the power semiconductor element 110 becomes 0 V, the cutoff circuit control signal Vs becomes the voltage Vzd, the collector current Ic becomes 0 A, and the collector voltage Vc rapidly increases to the voltage Vb, as in the example of FIG. , Respectively.

  As described above, the semiconductor device 200 can make the gate potential Vg smaller than the threshold Vthi at the time t7d ′ earlier than the time t7d. That is, in the semiconductor device 200 of the second modification, the period from time t7a to time t7c ′ is shorter than the period from time t7a to time t7c of the semiconductor device 100 shown in FIG. Can be shortened.

  FIG. 12 shows a third modification of the ignition device 2000 according to this embodiment. In the ignition device 2000 of the third modified example, the same reference numerals are given to the substantially same operations as those of the ignition device 2000 of the second modified example shown in FIG. The ignition device 2000 according to the third modification further includes a delay circuit 230.

  The delay circuit 230 is provided between the interruption condition detection unit 130 and the interruption circuit 120 and delays a signal transmitted from the interruption condition detection unit 130 to the interruption circuit 120. The delay circuit 230 may include a resistive element and a capacitive element. The delay circuit 230 may include an inductance element and a capacitive element. The delay circuit 230 may be a filter circuit that reduces high frequency components such as noise. FIG. 12 shows an example in which the delay circuit 230 includes a resistor 232 and a capacitor 234.

  In this case, the delay circuit 230 delays the signal passing through the delay circuit 230 by a delay time determined according to the resistance value of the resistor 232 and the capacitance value of the capacitor 234. That is, the cutoff circuit control signal Vs output from the signal output unit 134 of the cutoff condition detection unit 130 is delayed by the delay circuit 230 and then input to the cutoff circuit 120. Thereby, when the power semiconductor element 110 is in the ON state, even if the cutoff circuit control signal Vs output from the signal output unit 134 temporarily becomes a high potential, if it becomes a low potential in a time shorter than the delay time. The power semiconductor element 110 can be prevented from switching off.

  For example, the cutoff condition detection unit 130 may malfunction due to noise or the like, and the cutoff circuit control signal Vs may suddenly become a high potential. In such a case, the ignition device 2000 of the third modification can prevent malfunction of the power semiconductor element 110 if the cutoff circuit control signal Vs returns to a low potential in a time shorter than the delay time. Next, the transient response of the ignition device 2000 of the third modified example will be described.

  FIG. 13 shows an example of the operation waveform of each part of the semiconductor device 200 of the third modification. FIG. 13 shows an example of an operation waveform when the control signal Vin shown in the operation waveform shown in FIG. Note that the horizontal axis and the vertical axis in FIG. 13 are shown on substantially the same scale as the horizontal axis and the vertical axis of the operation waveform shown in FIG. 9.

  That is, the horizontal axis in FIG. 13 represents time, and the vertical axis represents voltage value or current value. In FIG. 13, the control signal input from the control terminal 202 is “Vin”, the detection signal output from the detection unit 132 is “Vt”, the cutoff circuit control signal output from the signal output unit 134 is “Vs”, and the cutoff circuit The cutoff circuit control signal input to the gate of 120 is “Vs ′”, the potential of the gate terminal of the power semiconductor element 110 is “Vg”, the collector current of the power semiconductor element 110 is “Ic”, and the collector voltage of the power semiconductor element 110 is Each time waveform is shown as “Vc”.

  In FIG. 13, the time when the control signal Vin is turned off is t7a. The detection signal Vt output from the detection unit 132 becomes a low potential at time t7a in accordance with the control signal Vin. In response to the control signal Vin being turned off, the cutoff circuit control signal Vs output from the signal output unit 134 becomes a high potential. Here, since the delay circuit 230 is provided between the signal output unit 134 and the cutoff circuit 120, the cutoff circuit control signal Vs ′ input to the gate of the cutoff circuit 120 has a time constant determined by the resistor 232 and the capacitor 234. In response, gradually increase.

  At time t7a ′, when the cutoff circuit control signal Vs ′ input to the gate of the cutoff circuit 120 reaches the threshold value Vths of the cutoff circuit 120, the cutoff circuit 120 shifts to the on state. The gate potential Vg of the power semiconductor element 110 gradually decreases from the time t7a ′ to the time t7b ″ in accordance with the transition of the cutoff circuit 120 to the ON state. Note that the time t7b ″ is the time t7b shown in FIG. 'May be substantially the same time as the time delayed by the delay time of the delay circuit 230. Similarly, each of time t7c "and time t7d" shown in FIG. 13 may be substantially the same as the time delayed by the delay time of delay circuit 230 from each of time t7c 'and time t7d' shown in FIG. .

  Further, since the semiconductor device 200 of the third modified example has a configuration in which the delay circuit 230 is added to the semiconductor device 200 of the second modified example, the operation waveform of each part after the time t7b "is after the time t7b 'shown in FIG. The operation waveform is the same as the operation waveform of each unit, and the cutoff circuit control signal Vs ′ input to the gate of the cutoff circuit 120 delays the cutoff circuit control signal Vs output from the signal output unit 134 according to the time constant. 13 shows an example in which the high-frequency signal is removed by the filtering effect of the delay circuit 230 as compared with the cutoff circuit control signal Vs of FIG.

  As described above, the semiconductor device 200 according to the third modification example has a pulse shorter than the delay time while performing the operation substantially similar to the operation of the semiconductor device 200 according to the second modification example by adding the delay circuit 230. Even if the noise of the width is mixed in the cutoff circuit control signal Vs, it is possible to prevent the power semiconductor element 110 from malfunctioning.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

DESCRIPTION OF SYMBOLS 10 Control signal generation part, 20 Spark plug, 30 Ignition coil, 32 Primary coil, 34 Secondary coil, 40 Power supply, 100 Semiconductor device, 102 Control terminal, 104 1st terminal, 106 2nd terminal, 110 Power semiconductor element, 120 Blocking circuit, 130 Blocking condition detection unit, 132 detection unit, 134 signal output unit, 140 input terminal, 150 resistor, 160 resistor, 170 Zener diode, 200 semiconductor device, 202 control terminal, 204 first terminal, 206 second terminal, 210 First rectifier element, 220 Second rectifier element, 230 delay circuit, 232 resistor, 234 capacitor, 302 control signal input unit, 304 detection signal output unit, 306 reference potential input unit, 310 resistor, 320 resistor, 330 inverter 340 Inverter, 350 Switch element , 1000 ignition device, 2000 ignition device

Claims (12)

A power semiconductor element connected between a first terminal on a high potential side and a second terminal on a low potential side and controlled to be turned on or off according to a gate potential;
A blocking condition detection unit that detects whether a control signal that is input from a control terminal and controls the power semiconductor element satisfies a predetermined blocking condition;
A cutoff circuit that controls the gate potential of the power semiconductor element to an off potential in response to detecting that the cutoff condition detection unit satisfies the cutoff condition;
With
The shut-off condition detecting unit has an input terminal connected to the first terminal and the control terminal, and uses an electric signal input from the input terminal as a power source. A first rectifying element connected between the control terminal and the input terminal of the blocking condition detection unit;
A second rectifying element connected between the first terminal and the input terminal of the cutoff condition detection unit;
A semiconductor device according to claim 1. A power semiconductor element connected between a first terminal on a high potential side and a second terminal on a low potential side and controlled to be turned on or off according to a gate potential;
A blocking condition detection unit that detects whether a control signal that is input from a control terminal and controls the power semiconductor element satisfies a predetermined blocking condition;
A cutoff circuit that controls the gate potential of the power semiconductor element to an off potential in response to detecting that the cutoff condition detection unit satisfies the cutoff condition;
With
The blocking condition detector is
An input terminal connected to the first terminal, a gate terminal of the power semiconductor element, and the control terminal via a resistive element;
A semiconductor device using an electric signal input from the input terminal as a power source. A first rectifying element connected between the resistive element and the input terminal of the blocking condition detection unit;
A second rectifying element connected between the first terminal and the input terminal of the cutoff condition detection unit;
A semiconductor device according to claim 3.   The semiconductor device according to claim 3, wherein the resistive element is a resistor or a switch element. The blocking condition detector is
A detection unit for detecting whether the control signal exceeds a predetermined threshold;
A signal output unit that outputs a cutoff circuit control signal for controlling the cutoff circuit according to a detection result of the detection unit;
The semiconductor device according to claim 2, comprising:   The semiconductor device according to claim 6, wherein the signal output unit is connected to the first rectifier element and the second rectifier element, and uses an electric signal input from the first terminal and the control terminal as a power source.   The semiconductor device according to claim 2, wherein a resistor or a switch element is connected between the first terminal and the second rectifier element.   9. The semiconductor device according to claim 1, wherein the cutoff circuit electrically connects a gate and an emitter of the power semiconductor element so that the gate of the power semiconductor element is turned off.   The semiconductor device according to claim 1, wherein the power semiconductor element is an IGBT (Insulated Gate Bipolar Transistor) or a vertical MOSFET.   11. The delay circuit according to claim 1, further comprising a delay circuit that is provided between the cutoff condition detection unit and the cutoff circuit and delays a signal that the cutoff condition detection unit transmits to the cutoff circuit. Semiconductor device.   The semiconductor device according to claim 1, wherein the semiconductor device is an igniter that controls a current flowing through the ignition coil in accordance with a control signal from the outside.

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