Semiconductor module

Abstract

A semiconductor module that implements a noise countermeasure for a control device and suppresses an increase in cost is provided. The semiconductor module is configured such that a first switching device and a second switching device, a first control device and a second control device are packaged by a package having a rectangular shape in plan view, in the semiconductor module, signals to the first control device and the second control device are input from a plurality of signal terminals provided on a side surface of a first long side of the package, outputs of the first switching device and the second switching device are output from output terminals provided on a side surface of a second long side, control grounds of the first control device and the second control device are connected to control ground terminals provided on the side surface of the first long side, a main power supply terminal and a power supply ground terminal are provided on the side surface of the second long side, the power supply ground terminal is electrically connected to the control ground terminal inside the package via a current detection resistor provided outside the package and an impedance member provided inside the package.

Description

TECHNICAL FIELD

[0001] The present application relates to a semiconductor module, and particularly to a semiconductor module in which a power semiconductor element and a control circuit thereof are packaged by transfer molding. BACKGROUND

[0002] A semiconductor module in which a switching device such as an IGBT (Insulated Gate Bipolar Transistor) and a control device that performs drive control of the switching device are packaged is called an IPM (Intelligent Power Module), but in the case of the conventional IPM, a current detection resistor, so-called shunt resistor, that detects a main current of the switching device is connected outside the package, and the main current is monitored, whereby an abnormal operation such as generation of a short-circuit current is detected, and short-circuit protection is performed.

[0003] In the case where a short-circuit current is generated, an electromotive force is generated by a current change (di / dt) at the time of current interruption and a wiring inductance between an emitter and a ground of a power circuit, i.e., a power supply ground. In order that a ground current caused by the electromotive force does not flow into a ground of a control device, i.e., a control ground, of the semiconductor module, an impedance is provided between the power supply ground and the control ground as a noise countermeasure. In the power module disclosed in Patent Literature 1, Figure 1 one example of a power module to which a noise countermeasure is applied is disclosed.

[0004] Patent Literature 1: International Publication No. 2020 / 017169

[0005] In the case of the power module disclosed in Patent Literature 1, an external resistor is provided as an impedance for a noise countermeasure, and there is a problem that the cost increases due to an increase in the number of components. SUMMARY

[0006] The present application has been made to solve the above-described problems, and has an object to provide a semiconductor module in which a noise countermeasure against a control device is implemented and an increase in cost is suppressed.

[0007] The semiconductor module according to the present application includes: a first switching device and a second switching device connected in series between a main power terminal and a power ground terminal, and complementarily operated; a first control device that controls driving of the first switching device; and a second control device that controls driving of the second switching device, the first switching device and the second switching device and the first control device and the second control device are packaged in a package having a rectangular shape in a plan view, in the semiconductor module, signals to the first control device and the second control device are input from a plurality of signal terminals provided on a side surface of a first long side of the package, outputs of the first switching device and the second switching device are output from an output terminal provided on a side surface of a second long side, control grounds of the first control device and the second control device are connected to a control ground terminal provided on the side surface of the first long side, the main power terminal and the power ground terminal are provided on the side surface of the second long side, the power ground terminal is electrically connected to a current detection resistor provided outside the package, and the control ground terminal is electrically connected to the current detection resistor and an impedance member provided inside the package.

[0008] Effects of the Invention

[0009] According to the semiconductor module of the present application, the power ground terminal is electrically connected to the control ground terminal inside the package via the current detection resistor provided outside the package and the impedance member provided inside the package, so that the impedance of the impedance member can be set in a manner that eliminates the frequency of the electromotive force caused by the short-circuit current of the switching device, thereby enabling implementation of a noise countermeasure for the control device, and enabling suppression of an increase in cost by providing the impedance member inside the package. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 is a circuit diagram showing the structure of the inverter module of Embodiment 1.

[0011] Figure 2 is an internal wiring diagram showing the structure of the inverter module of Embodiment 1.

[0012] Figure 3 is an internal wiring diagram showing the structure of the inverter module of Embodiment 2.

[0013] Figure 4 is an internal wiring diagram showing the structure of the inverter module of Embodiment 3.

[0014] Figure 5 is an internal wiring diagram showing the structure of the inverter module of Embodiment 4.

[0015] Figure 6 is a partial enlarged view of the inverter module of Embodiment 4.

[0016] Figure 7 is a diagram for explaining a noise countermeasure for the semiconductor module. DETAILED DESCRIPTION

[0017] <INTRODUCTION>

[0018] Before the explanation of the embodiments, a noise countermeasure originating from a short-circuit current is explained. Figure 7 is a circuit diagram showing a circuit structure of a semiconductor module MD in which only an IGBT 1 and a drive circuit DIC are packaged, as an example of a semiconductor module in which the noise countermeasure is implemented, in which the drive circuit DIC performs drive control of the IGBT 1.

[0019] As shown in Figure 7 , the semiconductor module MD has the IGBT 1 connected between a collector terminal CT and an emitter terminal ET, and a gate of the IGBT 1 is connected to an output node ND of the drive circuit DIC.

[0020] The drive circuit DIC has a gate driver composed of a P-channel MOS transistor MT1 and an N-channel MOS transistor MT2 connected in series between a drive voltage terminal VCC to which a drive voltage is supplied from a direct-current power supply PW and a control ground terminal VNC, and a connection node of the two transistors becomes the output node ND. Further, for the drive circuit DIC, a structure other than the gate driver is omitted for convenience.

[0021] An emitter of the IGBT 1 is connected to one end of a shunt resistor SR via the emitter terminal ET, and the other end of the shunt resistor SR is connected to a power supply ground GND and to the control ground terminal VNC via an external resistor OIP. A wiring that connects the control ground terminal VNC and the power supply ground GND as shown above is called a gate charge return wiring GCR.

[0022] As explained before, in a case where a short-circuit current is generated in a switching device, an electromotive force is generated by a current change (di / dt) at the time of current interruption and a wiring inductance ID between the emitter and the power supply ground. A ground current caused by the electromotive force, if flowing into the control ground of the drive circuit DIC, can affect the N-channel MOS transistor MT2 by noise, and therefore, the external resistor OIP is connected between the power supply ground and the control ground to make the impedance Z large. The gate charge return wiring GCR constitutes a charge-discharge path for charging and discharging the gate of the IGBT 1, which is shown by an arrow. The N-channel MOS transistor MT2 is included in the charge-discharge path, and therefore, the noise is reduced by making the impedance Z large by providing the external resistor OIP.

[0023] Embodiment 1

[0024] Next, the structure of the semiconductor module of Embodiment 1 will be described. Figure 1 and Figure 2 The structure of the semiconductor module of Embodiment 1 will be described. Figure 1 is a diagram showing the structure of the inverter module 100 of a 3-phase full bridge, Figure 2 is an internal wiring diagram of the inverter module 100, and only the main parts are shown. Further, in Figure 2 , the setting region of the package PG is shown by a broken line.

[0025] As shown in Figure 1 , the inverter module 100 is an IPM (Intelligent Power Module) in which a switching device and a control circuit that controls the drive of the switching device are resin-sealed, and as shown in Figure 2 , the inverter module 100 is of a DIP (Dual-In-line Package) configuration in which one column of terminal columns is provided on each of the two long sides of the package PG.

[0026] As shown in Figure 1 , the inverter module 100 has each group of N-channel type IGBTs 11 and 12, IGBTs 21 and 22, and IGBTs 31 and 32 connected in series between a terminal P that is a main power supply terminal of a high potential and a terminal NU that is a power supply ground terminal, and the connection nodes thereof are connected to output terminals W, V, and U of the W-phase, V-phase, and U-phase of the package PG. Further, the output terminals U, V, and W are connected to each phase of a 3-phase motor, for example.

[0027] A freewheeling diode 111, 121, 211, 221, 311, and 321 is connected in antiparallel to each of the IGBTs 11, 12, 21, 22, 31, and 32. Further, a control device HIC is provided in order to control the IGBTs 11, 21, and 31 that are the first switching devices, that is, the devices on the high potential side. Further, the control device HIC is a so-called HVIC (High Voltage Integrated Circuit), and a control output signal is supplied from the control device HIC to the gate electrode of each of the IGBTs 11, 21, and 31.

[0028] Further, within the inverter module 100, a control device LIC is provided for controlling the IGBTs 12, 22, and 32, which are the second switching devices, i.e., low-potential side devices. The control device LIC is a so-called LVIC (Low Voltage Integrated Circuit), and control output signals of the control device LIC are supplied to the respective gate electrodes of the IGBTs 12, 22, and 32. Further, the control devices HIC and LIC operate in accordance with a drive voltage from the direct-current power supply PW, and a control ground of the control devices HIC and LIC is commonly connected to the control ground terminal VNC.

[0029] The emitters of the IGBTs 12, 22, and 32 are connected to one end of an external shunt resistor SR via the terminal NU, and the other end of the shunt resistor SR is connected to the power supply ground GND and to the terminal NV. The terminal NV is electrically connected to the control ground via an impedance member IIP provided within the inverter module 100.

[0030] Here, the use of Figure 2 The detailed structure of the inverter module 100 will be described. As shown in FIG. 1, the inverter module 100 is provided with a lead frame LF1 on which the control devices LIC and HIC are mounted on the first long side of a rectangular package PG, and a lead frame LF2 on which the IGBTs and the freewheeling diodes are mounted on the second long side. Figure 2

[0031] The lead frame LF1 has a plurality of lead terminals LT1 that become signal terminals, and a die pad P11 on which the control devices LIC and HIC are mounted.

[0032] The die pad P11 extends in a direction parallel to the long side of the package PG, and is connected to one of the lead terminals LT1. The control devices LIC and HIC mounted on the die pad P11 are connected to the lead terminals LT1 by wire bonding, and are supplied with various signals and drive voltages.

[0033] The lead frame LF2 has seven lead terminals LT2, die pads P1 to P4, and wire bonding regions P20, P21 to P23.

[0034] The die pads P1 to P4 are arranged in a manner parallel to the long side of the package PG, and are independent of each other. Further, the wire bonding regions P21 to P23 are provided in a manner integral with the die pads P2 to P4, respectively, and the lead terminals LT2 are connected in a manner integral with the wire bonding regions P21 to P23, respectively. Further, the lead terminals LT2 are connected in a manner integral with the die pads P1 and the wire bonding region P20, respectively, and the wire bonding regions P20 to P23 are arranged in a manner parallel to the long side of the package PG. ​

[0035] Here, the lead terminal LT2 integrated with the die pad P1 corresponds to Figure 1 The lead terminal LT2 integrated with the wire bonding region P20 corresponds to the terminal NU.

[0036] In the lead frame LF1 shown in Figure 2 In the lead frame LF1 shown in

[0037] In addition, the freewheeling diodes 111, 211, 311 are arranged above the die pad P1 in a manner opposite to each of the IGBTs 11, 21, 31, and the freewheeling diodes 321, 221, 121 are arranged above the die pads P2 to P4 in a manner opposite to each of the IGBTs 32, 22, 12, respectively.

[0038] In addition, the freewheeling diodes 111, 211, 311 are arranged above the die pad P1 in a manner opposite to each of the IGBTs 11, 21, 31, and the freewheeling diodes 321, 221, 121 are arranged above the die pads P2 to P4 in a manner opposite to each of the IGBTs 32, 22, 12, respectively.

[0039] In addition, the freewheeling diodes 111, 211, 311 are arranged above the die pad P1 in a manner opposite to each of the IGBTs 11, 21, 31, and the freewheeling diodes 321, 221, 121 are arranged above the die pads P2 to P4 in a manner opposite to each of the IGBTs 32, 22, 12, respectively.

[0040] In addition, the freewheeling diodes 111, 211, 311 are arranged above the die pad P1 in a manner opposite to each of the IGBTs 11, 21, 31, and the freewheeling diodes 321, 221, 121 are arranged above the die pads P2 to P4 in a manner opposite to each of the IGBTs 32, 22, 12, respectively.

[0041] In addition, the freewheeling diodes 111, 211, 311 are arranged above the die pad P1 in a manner opposite to each of the IGBTs 11, 21, 31, and the freewheeling diodes 321, 221, 121 are arranged above the die pads P2 to P4 in a manner opposite to each of the IGBTs 32, 22, 12, respectively.

[0042] In addition, the freewheeling diodes 111, 211, 311 are arranged above the die pad P1 in a manner opposite to each of the IGBTs 11, 21, 31, and the freewheeling diodes 321, 221, 121 are arranged above the die pads P2 to P4 in a manner opposite to each of the IGBTs 32, 22, 12, respectively.

[0043] WithFigure 1 The lead terminals LT2 corresponding to the unused terminals, i.e., the terminals NV and NW, are connected as shown Figure 2 as shown inside to the frame member FL constituting the impedance member IIP. Further, the lead terminal LT2 corresponding to the terminal NU and NV is connected as shown Figure 1 as shown inside to the frame member FL constituting the impedance member IIP. Further, the lead terminal LT2 corresponding to the terminal NU and NV is connected as shown Figure 2 The external shunt resistor SR is connected as shown inside.

[0044] The frame member FL is provided to connect the lead frame LF1 and the lead frame LF2 in parallel with the short side of the package PG, and on the lead frame LF1 side, the lead terminal LT1 corresponding to the control ground terminal VNC is connected. Figure 1 The lead terminal LT1 of the control ground terminal VNC is connected as shown inside.

[0045] The impedance of the impedance member IIP constituted by the frame member FL has a frequency characteristic such that the frequency of the electromotive force generated by the current change (di / dt) at the time of current interruption and the wiring inductance between the emitter and the power supply ground in the case where a short-circuit current is generated in the switching device is eliminated, is such that the peak value of the generated electromotive force is less than or equal to the allowable voltage, for example, less than or equal to the gate withstand voltage of the IGBT or the element withstand voltage of the control device LIC and HIC.

[0046] In the case of the semiconductor module constituted by the switching device such as the inverter module 100, the frequency of the electromotive force generated by the short-circuit current of the switching device can be derived from the rated value of the switching device or the like, and therefore, it is only necessary to set the width of the frame member FL so as to become an impedance capable of eliminating the electromotive force at the time of design of the semiconductor module, and therefore, it is possible to suppress an increase in cost due to the provision of the impedance member IIP.

[0047] Generally, the ferrite beads used for the noise countermeasure have an inductance component and a resistance component, and in the low frequency region, the inductance component mainly functions to reflect noise, and in the high frequency region, the resistance component mainly functions to absorb noise. Therefore, in the high frequency region, it is possible to remove a specific frequency component by adjusting the impedance, i.e., the resistance component.

[0048] As described above, in the inverter module 100, a part of the gate charge return wiring connecting the control ground terminal VNC and the power supply ground GND is constituted by the impedance member IIP provided inside the inverter module 100. Therefore, it is not necessary to provide an external resistor, and it is possible to suppress an increase in cost accompanying the addition of the external resistor. In addition, the impedance member IIP is provided inside the module, and therefore, it is possible to reduce the mounting area of the module as compared with the case where an external resistor is provided.

[0049] <Embodiment 2>

[0050] Next, the use ofFigure 3 The structure of the semiconductor module of Embodiment 2 will be described. Figure 3 is an internal wiring diagram of the inverter module 200 of a 3-phase full-bridge, and like the inverter module 100 using Figure 2 The same reference numerals are given to the same structures as those of the inverter module 100 described above, and repeated description will be omitted. Further, the circuit structure of the inverter module 200 is the same as that of the inverter module 100 shown in Figure 1

[0051] As shown in Figure 3 , in the inverter module 200, the lead terminal LT2 equivalent to the terminal NV and the terminal NW shown in Figure 1 is internally commonly connected and connected to the lead frame LFl equivalent to the control ground terminal VNC via the lead wire WR1, which constitutes the impedance member IIP. Figure 1

[0052] As described above, in the inverter module 200, the part of the gate charge return wiring that connects the control ground terminal VNC to the power supply ground GND is constituted by the lead wire WR1 provided inside the inverter module 200. Therefore, it is not necessary to provide an external resistor, and it is possible to suppress an increase in cost accompanying the addition of the external resistor. In addition, the impedance member IIP is provided inside the module, and thus, compared to the case where an external resistor is provided, it is possible to reduce the mounting area of the module.

[0053] In addition, the lead frames LFl and LF2 can use an existing frame, and it is not necessary to process the existing frame, and thus, it is possible to suppress an increase in cost caused by the provision of the impedance member IIP.

[0054] In addition, the impedance member IIP is constituted by the lead wire WR1, and thus, compared to the structure of the inverter module 100 constituted by the frame member FL, it is possible to increase the resistance value by the contact resistance between the lead wire WR1 and the frame. In addition, the lead wire WR1 is wire-bonded in a manner of forming a wire loop, and thus, compared to the structure of the inverter module 100 constituted by the frame member FL of a straight line shape, the length of the impedance member IIP is longer, and it is possible to increase the resistance value. Figure 2 Figure 2

[0055] Further, as the lead wire WR1, an aluminum lead wire or a gold lead wire can be used, and it is possible to adjust the impedance by changing the material.

[0056] <Embodiment 3>

[0057] Next, the structure of the semiconductor module of Embodiment 3 will be described. Figure 4 Figure 4 is an internal wiring diagram of the inverter module 300 of a 3-phase full-bridge, and like the inverter module 100 using Figure 2 ​​​​​The inverter module 100, which has the same structure as described above, is labeled with the same reference numerals, so repeated descriptions are omitted. Furthermore, the circuit structure of the inverter module 300 is the same as... Figure 1 The inverter module 100 shown is the same.

[0058] like Figure 4 As shown, in inverter module 300, with Figure 1 The lead terminal LT2 corresponding to terminals NV and NW shown is internally connected to the frame component FL that constitutes the impedance component IIP.

[0059] The frame component FL is configured to connect lead frame LF1 and lead frame LF2 and be parallel to the short side of the package PG, and on the lead frame LF1 side, it is equivalent to... Figure 1 The control ground terminal VNC shown is connected to the lead terminal LT1, but a portion of the lead terminal LT1 is cut off and separated from the die pad P11 that houses the control devices LIC and HIC. The cut portion is electrically connected to the die pad P11 by connecting the cut portion with the wire WR2. The frame component FL and the wire WR2 constitute the impedance component IIP.

[0060] As described above, in the inverter module 300, a portion of the gate charge return wiring connecting the control ground terminal VNC to the power ground GND is constituted by an impedance component IIP provided within the inverter module 300. Therefore, an external resistor is not required, suppressing the cost increase associated with adding an external resistor. Furthermore, since the impedance component IIP is located inside the module, the module's mounting area can be reduced compared to the case where an external resistor is used.

[0061] Furthermore, by cutting off a portion of the lead terminal LT1 and separating it from the die pad P11, and then connecting the cut portions electrically via the wire WR2, the resistance value can be increased by the contact resistance between the wire WR2 and the frame, compared to the case where only the frame component FL constitutes the impedance component IIP. In addition, the impedance of the impedance component IIP can be finely adjusted by finely adjusting the length of the wire WR2.

[0062] As a conductor, WR2 can use aluminum or gold conductors, and the impedance can be adjusted by changing the material.

[0063] <Implementation Method 4>

[0064] Next, use Figure 5 and Figure 6 The structure of the semiconductor module in Embodiment 4 will be described. Figure 5 This is the internal wiring diagram of a 3-phase full-bridge inverter module 400, for use... Figure 2The same structure as the inverter module 100 described above is assigned the same reference numeral, and repeated description is omitted. Further, the circuit structure of the inverter module 400 is the same as that of the inverter module 100 shown in FIG. 1. Figure 1

[0065] As shown in FIG. 4, in the inverter module 400, the lead terminal LT2 equivalent to the terminal NV and the terminal NW shown in FIG. 1 is internally connected in common with the frame member FL constituting the impedance member IIP. Figure 5 Figure 1

[0066] The frame member FL is provided to connect the lead frame LF1 and the lead frame LF2 in parallel with the short side of the package PG, and is connected on the lead frame LF1 side with the lead terminal LT1 equivalent to the control ground terminal VNC shown in FIG. 1. Figure 1

[0067] The front end of the lead terminal LT1 is integrated with the die pad P11 on which the control device LIC and the HIC are mounted, and is electrically connected to the control device LIC via a wire WR3 such as a gold wire. Figure 6 Figure 5 is an enlarged view of the region "A" in FIG. 4 including the control device LIC.

[0068] As shown in FIG. 5, the wire WR3 is connected to the upper surface terminal T1 of the control device LIC by wire bonding. The upper surface terminal T1 is a terminal connecting the internal circuit INC of the control device LIC and the control ground, and is electrically connected to the adjacent upper surface terminal T2 via an aluminum wiring IL10 inside the control device LIC, and the upper surface terminal T2 is electrically connected to the internal circuit INC via an aluminum wiring IL20. Figure 6

[0069] Thus, the structure is such that the frame member FL constitutes the impedance member IIP, and inside the control device LIC, the internal circuit INC is electrically connected to the control ground terminal VNC via the aluminum wirings IL10 and IL20. The impedance of the impedance member IIP is substantially increased by adding the impedance of the aluminum wirings IL10 and IL20, and therefore, it can be considered that the aluminum wirings IL10 and IL20 are part of the impedance member IIP.

[0070] As described above, in the inverter module 400, a part of the gate charge return wiring connecting the control ground terminal VNC and the power supply ground GND is constituted by the impedance member IIP provided inside the inverter module 400. Therefore, it is not necessary to provide an external resistor, and an increase in cost accompanying the addition of an external resistor can be suppressed. In addition, the impedance member IIP is provided inside the module, and therefore, compared with the case where an external resistor is provided, the mounting area of the module can be reduced.

[0071] ​​​​​​Further, by providing the internal circuit INC to be electrically connected to the control ground terminal VNC via the aluminum wiring IL10 and IL20 provided inside the control device LIC, the impedance of the aluminum wiring IL10 and IL20 is added, whereby the impedance of the impedance component IIP can be increased.

[0072] Further, the present application can freely combine each embodiment within the scope of the present application, or appropriately modify, omit each embodiment.

[0073] Explanation of Reference Numerals

[0074] 11, 12, 21, 22, 31, 32 IGBT, FL frame component, HIC, LIC control device, P, NU, VNC terminal, IIP impedance component, WR1, WR2 wiring.

Claims

1. A semiconductor module having: a first switching device and a second switching device which are connected in series between a main power terminal and a power ground terminal, and which complementarily act; a first control device which controls driving of the first switching device; and a second control device which controls driving of the second switching device, the first switching device and the second switching device and the first control device and the second control device being packaged by a package which is rectangular in a plan view, in the semiconductor module, a signal to the first control device and the second control device is input from a plurality of signal terminals provided on a side surface of a first long side among the first long side and a second long side of the package, an output of the first switching device and the second switching device is output from an output terminal provided on a side surface of the second long side, a control ground of the first control device and the second control device is connected to a control ground terminal provided on a side surface of the first long side, the control ground terminal is connected to a control power source outside of the package, the main power terminal and the power ground terminal are provided on a side surface of the second long side, the power ground terminal is connected to a current detection resistor provided outside of the package, and is electrically connected to the control ground terminal inside of the package via the current detection resistor and an impedance member provided inside of the package.

2. The semiconductor module according to claim 1, wherein the impedance member is constituted by a frame member which connects an unused terminal provided on a side surface of the second long side and the control ground terminal inside of the package, and the current detection resistor is connected to the unused terminal outside of the package.

3. The semiconductor module according to claim 1, wherein the impedance member is constituted by a wire which connects an unused terminal provided on a side surface of the second long side and the control ground terminal inside of the package, and the current detection resistor is connected to the unused terminal outside of the package.

4. The semiconductor module according to claim 1, wherein the impedance member is constituted by a frame member which connects an unused terminal provided on a side surface of the second long side and the control ground terminal inside of the package, and a part of a portion of the control ground terminal which is connected to the control ground is cut, the wire electrically connects between the cut portions, and the current detection resistor is connected to the unused terminal outside of the package.

5. The semiconductor module according to claim 3 or 4, wherein the wire is constituted by an aluminum wire or a gold wire.

6. The semiconductor module according to claim 1, wherein the impedance member is constituted by a frame member which connects an unused terminal provided on a side surface of the second long side and the control ground terminal inside of the package, and an internal wiring which is provided inside of the second control device, and which connects an internal circuit of the second control device and the control ground terminal. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The current detection resistor is connected to the unused terminal outside the package.

7. The semiconductor module according to claim 6, wherein The internal wiring is composed of aluminum wiring.

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