JP6270549B2 - Semiconductor device, motor using the same, and air conditioner - Google Patents

Description

  The present invention relates to a semiconductor device applicable to motor driving, a motor using the semiconductor device, and an air conditioner.

  In recent years, AC motors are driven at a variable speed by an inverter circuit composed of power semiconductor switching elements. A technique is known in which a motor drive device including the inverter circuit and its control circuit is configured by a semiconductor integrated circuit of one semiconductor chip or a plurality of semiconductor chips to reduce the size of the motor drive device (see, for example, Patent Document 1).

  An example of a semiconductor device for driving a high voltage motor according to the above prior art will be described with reference to FIG.

  The high breakdown voltage motor driving semiconductor device 10 in FIG. 11 (hereinafter referred to as a high breakdown voltage motor driving IC) includes a high breakdown voltage motor driving semiconductor chip 10 '. T1 to T6 in FIG. 11 are six switching elements for driving a three-phase motor, and are IGBTs (Insulated Gate Bipolar Transistors) in the example of FIG. D1 to D6 are free-wheeling diodes connected in antiparallel to the respective IGBTs. P1 is a U-phase output terminal, P2 is a V-phase output terminal, and P3 is a W-phase output terminal. These output terminals are connected to the stator coil 8 of the motor.

  VUT is a U-phase upper arm control signal, is input from the U-phase upper arm control signal input terminal P11, and is transmitted through a path of logic circuit LG → upper arm drive circuit KT → U-phase upper arm IGBT T1. VVT is a V-phase upper arm control signal, is input from the V-phase upper arm control signal input terminal P12, and is transmitted through a path of logic circuit LG → upper arm drive circuit KT → V-phase upper arm IGBT T2. VWT is a W-phase upper arm control signal, is input from the W-phase upper arm control signal input terminal P13, and is transmitted through a path of logic circuit LG → upper arm drive circuit KT → W-phase upper arm IGBT T3.

  VUB is a U-phase lower arm control signal, is input from the U-phase lower arm control signal input terminal P14, and is transmitted through a path of logic circuit LG → lower arm drive circuit KB → U-phase lower arm IGBT T4. VVB is a V-phase lower arm control signal, is input from the V-phase lower arm control signal input terminal P15, and is transmitted through a path of logic circuit LG → lower arm drive circuit KB → V-phase lower arm IGBT T5. VWB is a W-phase lower arm control signal, is input from the W-phase lower arm control signal input terminal P16, and is transmitted through a path of logic circuit LG → lower arm drive circuit KB → W-phase lower arm IGBT T6.

  The control semiconductor device 7 outputs the six control signals VUT, VVT, VWT, VUB, VVB, and VWB.

  In FIG. 11, the charge pump circuit CH is a circuit that generates the power supply voltage VCP for driving the upper arm IGBT. Diodes D7 and D8 and capacitors C3 and C4 are external components for the charge pump circuit. The clock signal VCL for operating the charge pump circuit CH is generated by an internal circuit of the high-voltage motor driving IC 10 and input to the charge pump circuit CH.

  The internal power supply circuit 11 generates the power supply voltage VB of the control semiconductor device 7 based on the drive circuit power supply voltage Vcc. The overcurrent detection circuit 16 outputs an overcurrent detection signal to the logic circuit LG when the voltage of the shunt resistor Rs exceeds a certain level.

  The control semiconductor device 7 receives the power supply voltage VB from the high breakdown voltage motor driving IC 10 and outputs six control signals VUT, VVT, VWT, VUB, VVB, and VWB to the high breakdown voltage motor driving IC 10.

  C1, C2, and C5 in FIG. 11 are power supply stabilization capacitors.

  In the high-voltage motor driving IC 10 as described above, if an overvoltage such as a surge voltage is applied to the high-voltage power supply voltage VDC, the high-voltage motor driving IC 10 may break down. Therefore, in the conventional technique shown in FIG. 11, a Zener diode ZD is externally connected by wiring on the printed circuit board between the high-voltage power supply potential VDC and the ground potential in order to prevent a failure due to a surge voltage.

JP 2008-228547 A

  In the above prior art, an overvoltage due to a surge voltage is suppressed by disposing an external Zener diode on the printed circuit board. However, when an overvoltage occurs due to a regenerative current, current flows through the Zener diode for a long time, unlike an overvoltage caused by a surge voltage. At this time, the Zener voltage has a relatively large positive temperature dependency, and therefore increases as the temperature rises. If the Zener voltage exceeds the withstand voltage of the high voltage motor driving IC, the high voltage motor driving IC may break down.

  In order to prevent this, it is necessary to improve the breakdown voltage of the high breakdown voltage motor driving IC. In order to improve the withstand voltage of the high voltage motor driving IC, in the element structure of all elements to which a high voltage is applied in the high voltage motor driving IC, the semiconductor layer is made low in concentration or thickened to increase the withstand voltage. There is a need to improve. However, the output stage elements (IGBTs T1 to 6 and the diodes D1 to 6 in FIG. 11) in the high withstand voltage motor driving IC have a trade-off relationship between the withstand voltage and the generated power loss. Generated power loss increases.

  Therefore, the present invention provides a semiconductor device capable of improving the overvoltage resistance performance while suppressing an increase in power loss, a motor using the semiconductor device, and an air conditioner.

In order to solve the above problems, a semiconductor device according to the present invention includes a power conversion circuit that outputs electric power for driving a motor by switching a plurality of semiconductor switching elements, and a drive circuit that drives the plurality of semiconductor switching elements. In order to suppress overvoltage due to surge voltage , a surge absorption diode connected between the power supply potential of the power conversion circuit and the ground potential is provided, the power conversion circuit, the drive circuit, the diode , Are sealed with resin so as to constitute one package. The power conversion circuit and the drive circuit are provided in the first semiconductor chip, the diode is provided in the second semiconductor chip, and the first semiconductor chip and the second semiconductor chip are arranged on a die pad made of a conductor. Alternatively, the power conversion circuit, the drive circuit, and the diode are provided in the first semiconductor chip. Furthermore, at the same temperature, the withstand voltage of the plurality of semiconductor switching elements is greater than the withstand voltage of the diodes, and the withstand voltages of the plurality of semiconductor switching elements and the withstand voltage of the diodes both have positive temperature dependence, and an overvoltage is generated by the regenerative current. In some cases, unlike the overvoltage due to the surge voltage, the temperature of the power conversion circuit, the drive circuit, and the diode is increased by the heat generation of the diode due to the current flowing through the diode for a long time.

  The motor according to the present invention includes a motor driving semiconductor device for applying a voltage to the stator coil, and the semiconductor device according to the present invention is used as the motor driving semiconductor device.

  Furthermore, the air conditioner according to the present invention includes an outdoor unit and an indoor unit, and the outdoor unit or the indoor unit has a fan motor, and the motor according to the present invention is used as the fan motor.

  According to the present invention, the temperature of the semiconductor switching element of the power conversion circuit rises due to the heat generated by the surge absorbing semiconductor element, so that the breakdown voltage of the semiconductor switching element can be increased when the temperature rises without changing the element structure. Thereby, the overvoltage resistance can be improved while suppressing an increase in power loss of the semiconductor device. Furthermore, according to the semiconductor device of the present invention, the reliability with respect to the overvoltage of the motor or the air conditioner is improved.

  Problems, configurations, and effects other than those described above will be clarified by the following description of examples.

1 shows a circuit configuration of a motor drive device that is Embodiment 1 of the present invention. A mounting structure example of a high voltage motor driving IC is shown. An example of temperature characteristics of withstand voltage in a semiconductor chip for driving a high voltage motor and a Zener diode chip is shown. 2 shows a circuit configuration of a motor drive device that is Embodiment 2 of the present invention. 3 shows a circuit configuration of a motor drive device that is Embodiment 3 of the present invention. 9 shows a circuit configuration of a motor drive device that is Embodiment 4 of the present invention. FIG. 9 is a schematic set diagram illustrating a configuration of a motor that is Embodiment 5 of the present invention. FIG. 10 is a schematic set diagram illustrating a configuration of a motor that is a modification of the fifth embodiment. FIG. 10 is a schematic external view showing a configuration of a motor that is another modified example of Embodiment 5. 9 shows a circuit configuration of a motor drive system that is Embodiment 6 of the present invention. 1 shows an example of a semiconductor device for driving a high voltage motor according to the prior art.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a circuit configuration of a motor drive apparatus that is Embodiment 1 of the present invention.

  A high breakdown voltage motor driving semiconductor device 10P (hereinafter referred to as a high breakdown voltage motor driving IC) of FIG. 1 includes a high breakdown voltage motor driving semiconductor chip 10 '. The breakdown voltage of the high voltage motor driving IC is, for example, about 100 to about 1000V. T1 to T6 in FIG. 1 are six semiconductor switching elements for driving a three-phase motor, and are IGBTs in the example of FIG. D1 to D6 in FIG. 1 are free-wheeling diodes connected in antiparallel to the respective IGBTs. The IGBTs T1 to T6 and the freewheeling diodes D1 to D6 constitute a power conversion circuit that supplies power by applying a voltage to the motor, that is, an inverter circuit including a three-phase bridge in this embodiment. P1 to P3 are three-phase AC output terminals, P1 is a U-phase output terminal, P2 is a V-phase output terminal, and P3 is a W-phase output terminal. These output terminals are connected to the stator coil 8 of the motor.

  VUT is a U-phase upper arm control signal, which is input from the U-phase upper arm control signal input terminal P11, and goes to the gate of IGBT T1 through a path of logic circuit LG → upper arm drive circuit KT → U-phase upper arm IGBT T1. Communicated. VVT is a V-phase upper arm control signal, which is input from the V-phase upper arm control signal input terminal P12, and goes to the gate of IGBT T2 through the path of logic circuit LG → upper arm drive circuit KT → V-phase upper arm IGBT T2. Communicated. VWT is a W-phase upper arm control signal, which is input from the W-phase upper arm control signal input terminal P13, to the gate of IGBT T3 through a path of logic circuit LG → upper arm drive circuit KT → W-phase upper arm IGBT T3. Communicated.

  VUB is a U-phase lower arm control signal, which is input from the U-phase lower arm control signal input terminal P14, and goes to the gate of IGBT T4 through a path of logic circuit LG → lower arm drive circuit KB → U-phase lower arm IGBT T4. Communicated. VVB is a V-phase lower arm control signal, which is input from the V-phase lower arm control signal input terminal P15, and goes to the gate of IGBT T5 through a path of logic circuit LG → lower arm drive circuit KB → V-phase lower arm IGBT T5. Communicated. VWB is a W-phase lower arm control signal, which is input from the W-phase lower arm control signal input terminal P16, to the gate of IGBT T6 through a path of logic circuit LG → lower arm drive circuit KB → W-phase lower arm IGBT T6. Communicated.

  The control semiconductor device 7 outputs these six control signals VUT, VVT, VWT, VUB, VVB, and VWB. In response to these control signals, the upper arm drive circuit KT drives the upper arm IGBTs T1 to T3 on and off, and the lower arm drive circuit KB drives the lower arms IGBTs T4 to T6 on and off. As a result, the inverter circuit converts the DC voltage of the power source into a three-phase AC voltage and outputs it to the output terminals P1 to P3. Then, by applying this three-phase AC voltage to the stator coil 8, a three-phase AC motor, for example, a permanent magnet type synchronous motor is driven at a variable speed.

  In FIG. 1, the control semiconductor device 7 and the high-voltage motor driving IC 10P are separate semiconductor devices, and the above six inputs (VUT, VVT, VWT, VUB, VVB, VWB) are used as control signals. However, the control semiconductor device 7 may be built in the high voltage motor driving IC 10P, and the motor speed command signal (Vsp) may be used as the control signal.

  In FIG. 1, the charge pump circuit CH is a circuit that generates the power supply voltage VCP for driving the upper arm IGBT. Diodes D7 and D8 and capacitors C3 and C4 are external components for the charge pump circuit. The clock signal VCL for operating the charge pump circuit CH is generated by an internal circuit (not shown) of the high voltage motor drive IC 10P and is input to the charge pump circuit CH.

  The internal power supply circuit 11 generates the power supply voltage VB of the control semiconductor device 7 based on the drive circuit power supply voltage Vcc. The overcurrent detection circuit 16 outputs an overcurrent detection signal to the logic circuit LG when the voltage of the shunt resistor Rs exceeds a preset level. When the logic circuit LG receives the overcurrent detection signal, the logic circuit LG transmits an off signal to the upper arm drive circuit KT and the lower arm drive circuit KB, thereby turning off the IGBTs T1 to T6. As a result, the high-voltage motor driving IC 10P can be protected from overcurrent.

  The control semiconductor device 7 receives the power supply voltage VB from the high voltage motor driving IC 10P and outputs six control signals VUT, VVT, VWT, VUB, VVB, VWB to the high voltage motor driving IC 10P. As the control semiconductor device 7, a general-purpose microcomputer or a motor control IC can be applied.

  C1, C2, and C5 in FIG. 1 are power supply stabilizing capacitors.

  As the semiconductor switching element constituting the output stage inverter circuit, the IGBT is used in the first embodiment. However, the semiconductor switching element is not limited to the IGBT but may be another semiconductor switching element such as a MOSFET or a junction bipolar transistor. In FIG. 1, the charge pump method is used as the upper arm driving method, but other circuit methods such as a bootstrap method may be used.

  In the first embodiment, a surge absorbing Zener diode is connected between the high-voltage power supply potential VDC and the ground potential in order to suppress overvoltage due to the surge voltage. A semiconductor chip ZDP (hereinafter referred to as a Zener diode chip) in which the Zener diode is formed and a semiconductor chip 10 'for driving a high voltage motor are disposed in one package.

  In this embodiment, a Zener diode is used as the surge absorbing semiconductor element. However, the present invention is not limited to this, and an avalanche diode, a surge voltage absorbing diode, a TVS (Transient Voltage Suppressor) diode, a constant voltage diode, or the like is used. May be. In addition, about the semiconductor element for surge absorption, a required withstand pressure | voltage may be obtained by one semiconductor junction structure, and may be obtained by connecting two or more in series.

  Next, the structure of the high voltage motor driving IC 10P will be described.

  FIG. 2 shows an example of a mounting structure of the IC 10P for driving the high voltage motor.

  As shown in FIG. 2, in the high withstand voltage motor driving IC 10P, the high withstand voltage motor driving semiconductor chip 10 'and the Zener diode chip ZDP are electrically connected to a die pad DP made of a metal conductor, such as solder or silver paste. Joined by materials. The high-voltage motor driving semiconductor chip 10 ', the Zener diode chip ZDP, the high-voltage power terminal lead LE1, and the ground terminal lead LE2 are electrically connected to each other by a conductive wire WI such as an aluminum wire. As a result, the circuit of the high-voltage motor driving IC 10P as shown in FIG. 1 is configured.

  High-voltage motor driving semiconductor chip 10 ', Zener diode chip ZDP, wire WI, high-voltage power terminal lead LE1, part of ground terminal lead LE2, part of die pad DP The resin is sealed with a resin RE, for example, an epoxy resin blended with a filler such as silica. Thereby, one package is constituted. In FIG. 2, in order to dissipate the heat generated by the IGBT and the diode of the inverter circuit to the outside, the back surface of the die pad DP opposite to the bonding surface of the high-voltage motor driving semiconductor chip 10 ′ and the Zener diode chip ZDP. Is exposed. When the amount of heat radiation is small or sufficient heat dissipation is obtained, the back surface of the die pad DP does not have to be exposed. In order to connect an external circuit, a part of the high-voltage power terminal lead LE1 and a part of the ground terminal lead LE2 are exposed to the outside from the resin RE.

  In the first embodiment, a regenerative current flows from the stator coil 8 toward the power source VDC. Since this regenerative current also flows in the Zener diode chip ZDP for a relatively long time, the Zener diode chip ZDP generates heat and the temperature of the Zener diode chip ZDP rises. When the temperature of the Zener diode chip ZDP rises, the heat generated by the Zener diode chip ZDP is transmitted to the high-voltage motor driving semiconductor chip 10 ′ through the die pad DP. For this reason, the temperature of the semiconductor chip 10 ′ for driving the high-voltage motor is also increased and becomes substantially the same temperature as the Zener diode chip ZDP. As a result, the breakdown voltage of the high breakdown voltage motor driving semiconductor chip 10 ', that is, the breakdown voltage value of the high breakdown voltage elements such as IGBTs T1 to T6 and diodes D1 to D6 in FIG. This will be described with reference to FIG.

  FIG. 3 shows an example of a temperature characteristic of the withstand voltage for the semiconductor chip 10 ′ for driving the high withstand voltage motor and the Zener diode chip ZDP.

  As shown in FIG. 3, the withstand voltage of the Zener diode chip ZDP, that is, the Zener voltage has a positive temperature dependency. For this reason, when the temperature rises due to heat generated by the regenerative current, the Zener voltage rises, and the overvoltage applied to the high-voltage motor driving semiconductor chip 10 'increases. On the other hand, since the withstand voltage of the high withstand voltage motor driving semiconductor chip 10 ′ also has a positive temperature dependency, the high withstand voltage motor is increased when the temperature of the high withstand voltage motor driving semiconductor chip 10 ′ increases due to the heat generated by the Zener diode chip ZDP. The breakdown voltage of the driving semiconductor chip 10 ′ increases. Therefore, the element structure of the high breakdown voltage semiconductor element in the high breakdown voltage motor driving semiconductor chip 10 ′ is set so that the breakdown voltage of the high breakdown voltage motor driving semiconductor chip 10 ′ is larger than the Zener voltage at the same temperature. For example, even if the Zener voltage increases as the temperature rises, the high breakdown voltage motor driving semiconductor chip 10 ′ can be protected from overvoltage. That is, the breakdown voltage of high breakdown voltage elements such as IGBTs T1 to T6 and diodes D1 to D6 is increased by temperature characteristics without depending on the element structure such as the thickness of the semiconductor layer and the impurity concentration. The overvoltage resistance performance of the driving semiconductor chip 10 ′ can be improved while suppressing an increase in power loss generated by the high breakdown voltage motor driving semiconductor chip 10 ′.

  The temperature characteristics of the withstand voltage of the Zener diode as described above are remarkable when the withstand voltage at room temperature (for example, 25 ° C.) is 100 V or more, according to the study of the present inventors.

  In this embodiment, the high-voltage motor driving semiconductor chip 10 'and the Zener diode chip ZDP are connected to the high-voltage power supply terminal and the ground terminal inside the high-voltage motor driving IC 10P. You may connect by printed wiring above.

  FIG. 4 shows a circuit configuration of a motor drive device that is Embodiment 2 of the present invention. In addition, about the same component as Example 1, while attaching | subjecting the same code | symbol as FIG. 1, detailed description is abbreviate | omitted.

  The main difference between the second embodiment and the first embodiment shown in FIG. 1 is that the high-voltage motor driving semiconductor chip 10 ′ in FIG. 1 is divided into a plurality of semiconductor chips in FIG. .

  In FIG. 4, the semiconductor chip 10MT1 is composed of a U-phase upper arm MOSFET and a free-wheeling diode connected in reverse parallel thereto, and the semiconductor chip 10MT2 is composed of a V-phase upper arm MOSFET and a free-wheeling diode connected in reverse parallel thereto. The semiconductor chip 10MT3 is composed of a W-phase upper arm MOSFET and a free-wheeling diode connected in antiparallel thereto. In addition, the semiconductor chip 10MT4 is configured by a U-phase lower arm MOSFET and a free-wheeling diode connected in reverse parallel thereto, and the semiconductor chip 10MT5 is configured by a V-phase lower arm MOSFET and a free-wheeling diode connected in reverse parallel thereto, The semiconductor chip 10MT6 is composed of a W-phase lower arm MOSFET and a free-wheeling diode connected in antiparallel thereto. The Zener diode for overvoltage protection is formed in the Zener diode chip ZDP. The circuit semiconductor chip 10MB is configured by another circuit, that is, a drive circuit unit that drives each MOSFET on and off.

  As the free wheel diode, a parasitic diode inside the MOSFET may be used in addition to the individual element. Each semiconductor chip is electrically connected by, for example, a wire or an inner lead (a resin-sealed portion of the lead).

  In the second embodiment, the semiconductor chips 10MT1 to 10MT6, the circuit semiconductor chip 10MB, and the Zener diode chip ZDP are arranged on a plurality of die pads DP (not shown). These die pads DP are resin-sealed with, for example, an epoxy resin blended with a filler such as silica to form one IC (10M in FIG. 4) having the same appearance as FIG. The epoxy resin blended with filler has a relatively large thermal conductivity, about 0.1 to 3 W / mK, as compared with air around the high voltage motor driving IC 10M on the printed circuit board. Therefore, even if the semiconductor chips 10MT1 to 10MT6, the circuit semiconductor chip 10MB, and the Zener diode chip ZDP are arranged on the plurality of die pads DP, the temperatures of the semiconductor chips 10MT1 to 10MT6, the temperature of the circuit semiconductor chip 10MB, and the Zener diode chip ZDP The temperature will be close. Therefore, also in the second embodiment, as in the first embodiment, the overvoltage resistance performance of the high-voltage motor driving IC can be improved while suppressing an increase in power loss.

  In this embodiment, the semiconductor chips 10MT1 to 10MT6, the circuit semiconductor chip 10MB, and the Zener diode chip ZDP are arranged on a plurality of die pads DP, but the same effect can be obtained even if they are arranged on one die pad DP. available.

  In the second embodiment, since each semiconductor switching element constituting the inverter circuit is constituted by an individual semiconductor chip, it is easy to increase the output power of the high voltage motor driving IC.

  As semiconductor switching elements constituting the semiconductor chips 10MT1 to 10MT6, IGBTs or junction bipolar transistors can be used in addition to the MOSFETs shown in FIG. In FIG. 4, the charge pump method is used as the upper arm drive method, but other methods such as a bootstrap method may be used. Further, in FIG. 4, one circuit semiconductor chip 10MB includes a drive circuit for three phases, but two circuit semiconductor chips, that is, the first and second circuit semiconductor chips are respectively for three phases. An upper arm circuit and a lower arm circuit for three phases may be provided. Three circuit semiconductor chips, that is, first, second, and third circuit semiconductor chips, each include a U-phase upper and lower arm circuit, a V-phase upper and lower arm circuit, and a W-phase upper and lower arm circuit, respectively. Also good.

  FIG. 5 shows a circuit configuration of a motor drive device that is Embodiment 3 of the present invention. In addition, about the same component as Example 1, while attaching | subjecting the same code | symbol as FIG. 1, detailed description is abbreviate | omitted.

  The difference between the present embodiment and the first embodiment shown in FIG. 1 is that the high breakdown voltage motor driving semiconductor chip 10 ′ and the Zener diode chip ZDP of the first embodiment are constituted by one semiconductor chip. .

  In FIG. 5, since the semiconductor device for driving a high voltage motor including the zener diode ZDS is integrated on one semiconductor chip, the temperatures of the high voltage devices such as IGBTs T1 to T6 and diodes D1 to D6 and the zener diode ZDS are The temperature is almost the same. For this reason, also in the second embodiment, as in the first embodiment, the overvoltage resistance performance of the high-voltage motor driving IC can be improved while suppressing an increase in power loss.

  In addition, according to the third embodiment, since the semiconductor device for driving a high voltage motor including the zener diode ZDS is integrated on one semiconductor chip, the semiconductor device for driving a high voltage motor can be reduced in size, and leads and die pads can be used. Wiring with can be simplified.

  In the third embodiment as well, a MOSFET, a junction bipolar transistor, or the like can be used as a switching element. Further, as the upper arm driving method, other methods such as a bootstrap method can be used.

  FIG. 6 shows a circuit configuration of a motor drive apparatus that is Embodiment 4 of the present invention. In addition, about the same component as Example 1, while attaching | subjecting the same code | symbol as FIG. 1, detailed description is abbreviate | omitted.

  In the fourth embodiment, unlike the first embodiment shown in FIG. 1, the high-voltage motor driving IC 10 </ b> T includes the overheat protection circuit 17. The overheat protection circuit 17 is provided in the high-breakdown-voltage motor driving semiconductor chip 10TC. When the temperature of the high withstand voltage motor driving IC 10T rises due to heat generated by the Zener diode and becomes equal to or higher than a preset overheat protection operating temperature, the overheat protection circuit 17 sends an overheat detection signal to the logic circuit LG. When receiving the overheat detection signal, the logic circuit LG turns off the control signals to the upper arm drive circuit KT and the lower arm drive circuit KB. As a result, the IGBTs of the upper and lower arms of the U phase, V phase, and W phase are all turned off, and the high-voltage motor driving IC 10T is in the overheat protection function operating state. When the temperature of the high-voltage motor driving IC 10T decreases to the overheat protection recovery temperature, the overheat protection circuit 17 sends a release signal to the logic circuit LG. When receiving the release signal, the logic circuit LG returns the control signals to the upper arm drive circuit KT and the lower arm drive circuit KB to the normal state. As a result, the overheat protection function operating state of the high-voltage motor driving IC 10T is released.

  As described above, according to the fourth embodiment, when the temperature of the high withstand voltage motor driving IC 10T is excessively increased due to the heat generated by the Zener diode, it is possible to prevent the breakdown of the high withstand voltage motor driving IC 10T due to overheating. Reliability is improved.

  FIG. 7 is a schematic set diagram showing a configuration of a motor that is Embodiment 5 of the present invention. In FIG. 7, main components are shown, and other peripheral components and detailed wiring configurations are omitted for simplicity (the same applies to FIG. 8 described later).

  The motor shown in FIG. 7 is a three-phase permanent magnet type synchronous motor such as a brushless motor, and a motor driving apparatus including a high voltage motor driving IC according to any one of the first to fourth embodiments is applied.

  As shown in FIG. 7, the control semiconductor device 7, the high breakdown voltage motor driving IC 10 </ b> P, the high voltage power supply voltage detection circuit 15, the shunt resistor Rs and the Hall IC 9 are arranged on the motor built-in substrate 6. In addition, the stator coil 8 of the motor is fitted in the lower housing casing 5B. The permanent magnet rotor 22 is installed inside the stator coil 8 with an appropriate gap provided so as not to touch the stator coil 8. The motor built-in substrate 6 is installed on the upper part of the permanent magnet rotor 22. The Hall IC 9 arranged on the motor built-in substrate 6 is provided on the surface of the motor built-in substrate 6 on the side of the permanent magnet rotor 22 (the lower surface in FIG. 7) so that the magnetic pole position of the permanent magnet rotor 22 can be easily detected. Be placed. The control semiconductor device 7, the high-voltage power supply voltage detection circuit 15, and the shunt resistor Rs are disposed on the surface of the motor-embedded substrate 6 on the permanent magnet rotor 22 side (the lower surface in FIG. 7). Is disposed on the surface of the motor-embedded substrate 6 opposite to the permanent magnet rotor 22 (upper surface in FIG. 7).

  A coil connection terminal 21 is disposed on the motor-embedded substrate 6, and the stator coil 8 is connected to the coil connection terminal 21 by soldering. The lead wiring 20 is connected to the motor built-in substrate 6 by soldering. The lead-out wiring 20 is composed of five wirings: a VDC wiring, a Vcc wiring, a Vsp (speed command signal) wiring, an FG (rotational speed signal) wiring, and a GND (grounding) wiring. The motor housing upper part 5A is installed on the motor-embedded substrate 6 like a lid. Therefore, in a state where the motor is assembled, the motor-embedded substrate 6 is disposed inside the motor casing composed of the motor casing upper part 5A and the motor casing lower part 5B.

  With the above configuration, a voltage can be applied to the stator coil 8 of the motor by the high-voltage motor driving IC 10 </ b> P disposed on the motor-embedded substrate 6.

  According to this embodiment, the motor driving device including the high-voltage motor driving IC according to any one of the first to fourth embodiments is incorporated, so that if the motor is connected to the power source, an individual driving device is used. The motor can be driven at a variable speed according to the speed command without any change. Therefore, a motor application device such as an air conditioner can be reduced in size. Moreover, since the overvoltage resistance performance of the motor drive unit is improved, the reliability of the motor is improved.

  FIG. 8 is a schematic assembly diagram showing a configuration of a motor which is a modification of the fifth embodiment. In the modification of FIG. 8, the lower casing 5B of the motor shown in FIG. 7 is not used, but a stator coil 5C molded with resin is used instead.

  FIG. 9 is a schematic external view showing a configuration of a motor that is another modification of the fifth embodiment. In the modification of FIG. 9, the stator coil 8 and the motor built-in substrate 6 are molded with resin instead of using the motor housing upper part 5A and the motor housing lower part 5B shown in FIG. 5D is provided.

  FIG. 10 shows a circuit configuration of a motor drive system that is Embodiment 6 of the present invention. Note that FIG. 10 shows a main circuit configuration, and some circuit portions are not shown for simplification.

  In the sixth embodiment, the power supply circuit 2 rectifies or converts the AC voltage of the commercial power supply 1 to generate DC voltages VDC, Vcc, and Vm. VDC is a high voltage of about 141 V to about 450 V, for example, and is used as a high-voltage power supply voltage for driving an inverter of a motor. Vcc is about 15 V, for example, and is a power supply voltage for a driving circuit such as an upper and lower arm driving circuit used in the high withstand voltage motor driving IC 10P. Vm is a power supply voltage for the microcomputer 3, for example, about 2V to about 5.5V. The power supply circuit 2 and the microcomputer 3 are disposed on a first circuit board 4 such as a printed circuit board.

  The microcomputer 3 outputs a speed command signal Vsp and inputs a rotation speed signal FG output from the motor 5. The microcomputer 3 adjusts the rotational speed of the motor 5 by this speed command signal Vsp. The speed command signal Vsp may be an analog signal or a pulse signal. In FIG. 10, the Vsp line and the FG line are directly connected between the microcomputer 3 and the control semiconductor device 7 by wiring, but may be connected via a photocoupler or a buffer circuit. The microcomputer 3 may output a pulsed speed command signal, convert the signal into an analog signal by a CR integration circuit including a capacitor and a resistor, and input the analog speed command signal to the control semiconductor device 7. .

  The motor built-in substrate 6 is built in the motor 5. The control semiconductor device 7, the high-voltage motor driving IC 10 </ b> P, the Hall IC 9, the shunt resistor Rs, and the high-voltage power supply voltage detection circuit 15 are arranged on the motor built-in substrate 6.

  As the motor 5, the motor shown in any of FIGS.

  Although not shown, Vcc or VB is used as the power supply voltage of the Hall IC 9. Instead of the Hall IC 9, a Hall element having a lower cost may be used. The Hall IC 9 and the Hall element operate as a magnetic pole position detector, and output a magnetic pole position signal indicating the position of the permanent magnet rotor of the motor 5. In the case of a Hall element, the output voltage of each Hall element is a voltage between two terminals. Usually, the output voltage of the Hall element is a minute voltage of 1 V or less, so that the signal is amplified using an amplifier. In FIG. 10, two Hall ICs are used as the magnetic pole position detector, but the number of magnetic pole position detectors may be three or one.

  The control semiconductor device 7 receives the power supply voltage VB, the speed command signal Vsp from the microcomputer 3, the high voltage power supply voltage signal Vh from the high voltage power supply voltage detection circuit 15, and the magnetic pole position signals VHU and VHV from the Hall IC 9. . Further, the control semiconductor device 7 outputs the control signals VU, VV, VW to the high voltage motor driving IC 10P, and outputs the rotation speed signal FG to the microcomputer 3.

  VB is a power supply voltage of the control semiconductor device 7, and is, for example, about 2V to about 7.5V. In FIG. 10, VB is generated inside the high-voltage motor driving IC 10P. However, VB may be generated from Vcc by an external regulator, a Zener diode, or the like. Alternatively, the power supply voltage for the control semiconductor device 7 may not be generated inside the motor 5, and Vm on the first circuit board 4 may be input to the control semiconductor device 7 instead.

  In FIG. 10, only the internal power supply circuit 11 and the protection circuit 14 are shown inside the high voltage motor driving IC 10P, but the detailed configuration is the same as in any of the first to fourth embodiments.

  The stator coil 8 of the motor 5 is connected to the output terminal of the high voltage motor driving IC 10P. The shunt resistor Rs is connected between the lower arm switching element of the high-voltage motor driving IC 10P and the ground potential. The shunt resistor Rs is used for detecting a current value of a main current flowing through a switching element such as an IGBT.

  The high voltage power supply voltage detection circuit 15 is connected to the high voltage power supply voltage VDC and outputs voltage information of the high voltage power supply voltage VDC as a high voltage power supply voltage signal Vh. In the example of FIG. 10, the high-voltage power supply voltage VDC is divided and converted into a low voltage Vh using two resistors connected in series and output.

  The control semiconductor device 7, the high-voltage motor driving IC 10 </ b> P, the high-voltage power supply voltage detection circuit 15, and the shunt resistor Rs may be arranged on the first circuit board 4 without being arranged on the motor-embedded board 6. it can.

  According to the tenth embodiment, since any one of the first to fourth embodiments is applied as the high-voltage motor driving IC 10P, the overvoltage resistance performance of the motor driving system is improved.

  An application example of the motor drive system shown in FIG. 10 is an air conditioner. The air conditioner includes an outdoor unit provided with a compressor that compresses a refrigerant, an outdoor heat exchanger, and an outdoor unit fan motor that blows air to the outdoor heat exchanger, and also sends air to the indoor heat exchanger and the indoor heat exchanger. The indoor unit is provided with an indoor unit fan motor that performs cooling or heating by switching the flow direction of the refrigerant using a valve.

  As a system for driving either one or both of the outdoor unit fan motor and the indoor unit fan motor, the motor driving system shown in FIG. 10 is used. This improves the reliability of the air conditioner against overvoltage. Further, by using the motor built-in substrate 6 on which the high-voltage motor driving IC 10P or the like is mounted as in the motor driving system shown in FIG. 10, that is, the motor shown in any of FIGS. By using it, an outdoor unit or an indoor unit can be reduced in size.

  In addition, this invention is not limited to Examples 1-6 mentioned above, Various modifications are included. For example, each of the above-described embodiments has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to one having all the configurations described. Furthermore, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  For example, the three-phase inverter circuit that supplies power for driving the motor may be another power conversion circuit including a single-phase inverter circuit. The motor is not limited to a permanent magnet type synchronous motor, and may be another motor that operates with AC power.

DESCRIPTION OF SYMBOLS 1 Commercial power supply 2 Power supply circuit 3 Microcomputer 4 Circuit board 5 Motor 5A Case upper part 5B Case lower part 5C Stator coil 5D Mold part 6 Motor built-in board 7 Control semiconductor device 8 Stator coil 9 Hall IC
10, 10P, 10M, 10S, 10T High breakdown voltage motor drive semiconductor device 10 ', 10TC, 10SC High breakdown voltage motor drive semiconductor chip 10MB Circuit semiconductor chip 10MT1-10MT6 Semiconductor chip ZDP Zener diode chip 11 Internal power supply circuit 14 Protection circuit 15 High voltage power supply voltage detection circuit 16 Overcurrent detection circuit 17 Overheat protection circuit 20 Lead wire 21 Coil connection terminal 22 Permanent magnet rotor T1, T2, T3, T4, T5, T6 Switching elements D1, D2, D3, D4, D5, D6 Freewheeling diodes ZD, ZDS Zener diode KT Upper arm drive circuit KB Lower arm drive circuit LG Logic circuit CH Charge pump circuit Rs Shunt resistors C1, C2, C5 Power stabilization capacitors C3, C4 Charge pump circuit capacitors D7 D8 Charge pump circuit diodes P1, P2, P3 Output terminals P11, P12, P13, P14, P15, P16 Control signal input terminal P21 High voltage power supply terminal P22 Ground terminal VDC High voltage power supply voltage Vcc Drive circuit power supply voltage Vsp Speed command signal FG Speed signal VHU, VHV Magnetic pole position signal Vm Power supply voltage VB for microcomputer Power supply voltage VUM, VVM, VWM for control semiconductor device Output voltage VUT, VVT, VWT, VUB, VVB, VWB Control signal Vh High voltage power supply voltage signal VCL Clock Signal VCP Upper arm drive power supply voltage DP Die pad WI Wire LE1 High voltage power supply terminal lead LE2 Ground terminal lead RE Resin

Claims (5)

In a semiconductor device comprising: a power conversion circuit that outputs power for driving a motor by switching a plurality of semiconductor switching elements; and a drive circuit that drives the plurality of semiconductor switching elements.
In order to suppress overvoltage due to surge voltage, a surge absorption diode connected between the power supply potential of the power conversion circuit and the ground potential,
The power conversion circuit, the drive circuit, and the diode are resin-sealed so as to form one package ,
The power conversion circuit and the drive circuit are provided in a first semiconductor chip, and the diode is provided in a second semiconductor chip;
The first semiconductor chip and the second semiconductor chip are disposed on a die pad made of a conductor;
Under the same temperature, the withstand voltage of the plurality of semiconductor switching elements is greater than the withstand voltage of the diode, and the withstand voltages of the plurality of semiconductor switching elements and the withstand voltage of the diode both have a positive temperature dependency,
When an overvoltage occurs due to a regenerative current, the temperature of the power conversion circuit, the drive circuit, and the diode is increased by heat generation of the diode due to the current flowing through the diode for a long time, unlike the overvoltage due to the surge voltage. A semiconductor device characterized by the above. In a semiconductor device comprising: a power conversion circuit that outputs power for driving a motor by switching a plurality of semiconductor switching elements; and a drive circuit that drives the plurality of semiconductor switching elements .
In order to suppress overvoltage due to surge voltage, a surge absorption diode connected between the power supply potential of the power conversion circuit and the ground potential,
The power conversion circuit, the drive circuit, and the diode are resin-sealed so as to form one package,
The power conversion circuit, the drive circuit, and the diode are provided in a first semiconductor chip;
Under the same temperature, the withstand voltage of the plurality of semiconductor switching elements is greater than the withstand voltage of the diode, and the withstand voltages of the plurality of semiconductor switching elements and the withstand voltage of the diode both have a positive temperature dependency,
When an overvoltage occurs due to a regenerative current, the temperature of the power conversion circuit, the drive circuit, and the diode is increased by heat generation of the diode due to the current flowing through the diode for a long time, unlike the overvoltage due to the surge voltage. A semiconductor device characterized by the above. The semiconductor device according to claim 1 or 2,
A semiconductor device comprising an overheat protection circuit that sends a detection signal when a temperature equal to or higher than a predetermined temperature is detected, wherein the plurality of semiconductor switching elements are turned off in response to the detection signal . In a motor incorporating a motor driving semiconductor device that applies a voltage to a stator coil,
3. A motor, wherein the motor driving semiconductor device comprises the semiconductor device according to claim 1. In an air conditioner comprising an outdoor unit and an indoor unit, the outdoor unit or the indoor unit having a fan motor,
The said fan motor consists of a motor of Claim 4, The air conditioner characterized by the above-mentioned.

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