Power semiconductor device, power module assembly and method for measuring current

Abstract

A power semiconductor device, a power module assembly, and a method for measuring current are disclosed. A packaged integrated power semiconductor device is proposed, which includes at least one power transistor coupled to a current path, a current measuring device, and a package. The current measuring device is electrically insulated from the current path and magnetically coupled to the current path. The current path and the current measuring device are arranged so that the current measuring device can sense the magnetic field of the current flowing through the current path. The power transistor, the current measuring device, and the current path are arranged inside the package. In addition, a power module assembly including the packaged integrated power semiconductor device and a method for operating the packaged integrated power semiconductor device are proposed.

Description

Technical Field

[0001] The present disclosure relates to a power semiconductor device, a power module assembly, and a method for measuring current. Background Art

[0002] In order to properly control the power semiconductor device and the load to which it is connected, the power semiconductor device requires current measurement. Typically, in order to measure the current in the power semiconductor device, an external current sensing element, such as a shunt or a magnetic sensor element (e.g., a Hall element, xMR, an open-loop or closed-loop magnetic transducer) is used. Although sensor units such as current mirrors are common solutions for integrated current measurement devices, the sensor units can only be used for unipolar low-voltage devices with a nominal blocking voltage of less than 100V. In bipolar power semiconductor devices such as IGBTs, due to the poor linearity and limited accuracy of the sensor units, they are only able to detect overload or short-circuit conditions. Therefore, bipolar power semiconductor devices such as IGBTs require external current measurement devices, which leads to an increase in engineering workload as well as space and cost.

[0003] In addition, the internal current measurement device does not provide functional isolation of the measurement signal and the load current. Typically, functionally isolated sensors are only available at relatively high costs, which makes them incompatible with cost-sensitive applications such as household appliances, electric hand tools, etc.

[0004] Therefore, there is a need for a low-cost power semiconductor device including an internal current measurement device that is functionally isolated.

[0005] The internal current measurement device needs to measure the load current, where the corresponding voltage swings between the positive and negative supply voltages with steep transients in the range of several kV / μs. Therefore, as the power semiconductor device operates under steep current and voltage transients, it is also necessary to isolate the sensor signal of the internal current measurement device from the interference generated by these transients. Summary of the invention

[0006] In order to solve the above problems, a packaged integrated power semiconductor device is proposed, which includes at least one power transistor coupled to a current path, a current measuring device and a package, wherein the current measuring device is electrically insulated from the current path and magnetically coupled to the current path, wherein the current path and the current measuring device are arranged so that the current measuring device can sense the magnetic field of the current flowing through the current path, and wherein the at least one power transistor, the current measuring device and the current path are arranged inside the package.

[0007] In some embodiments of the package-integrated power semiconductor device, the current measuring device may be arranged to extend along the length of the current path.

[0008] In some embodiments of the package-integrated power semiconductor device, the current measuring device may be arranged to at least partially surround the current measuring device.

[0009] In some embodiments of the package-integrated power semiconductor device, the current measuring device may be arranged to at least partially surround the current measuring device on three sides.

[0010] In some embodiments of the package-integrated power semiconductor device, a portion of the current path may be U-shaped, and the current measuring device may be arranged inside the U-shaped portion of the current path.

[0011] In some embodiments of the package-integrated power semiconductor device, at least one power transistor and the current measuring device may be arranged on separate die pads.

[0012] In some embodiments of a package-integrated power semiconductor device, a die pad, on which a current measuring device may be arranged, may be coupled to a reference potential.

[0013] In some embodiments of the packaged integrated power semiconductor device, the package may include an electrically insulating mold material, wherein the mold material may provide electrical insulation between the current measuring device and the current path.

[0014] In some embodiments, the package-integrated power semiconductor device may further include a thermally conductive insulator, and the package, the at least one power transistor, and the current path may be arranged on the thermally conductive insulator.

[0015] In some embodiments of the packaged integrated power semiconductor device, the thermally conductive insulator may include an inorganic material including at least one of the following materials: SiO 2 、Al 2 O 3 , AlN and Si 3 N 4 .

[0016] In some embodiments of the package-integrated power semiconductor device, the current measurement device may include a sensor element configured to detect a magnetic field generated by a current flowing through the current path.

[0017] In some embodiments of the package-integrated power semiconductor device, the sensor element may include at least two magnetoresistive elements.

[0018] In some embodiments of a packaged integrated power semiconductor device, at least one power transistor and a current measuring device may be arranged on separate die pads, and at least two magnetoresistive elements may be arranged on two opposite sides of the die pad on which the current measuring device may be arranged, wherein one of the opposite sides is the side closest to the current path and the other side of the opposite side is parallel to the one side.

[0019] In some embodiments of the package-integrated power semiconductor device, the current measuring device may include a metal shielding path, and the metal shielding path may at least partially surround the current measuring device.

[0020] In some embodiments of the package-integrated power semiconductor device, the metal shielding path may include at least one opening on a side of the metal shielding path opposite to the current path.

[0021] In some embodiments of the package-integrated power semiconductor device, the metal shielding path may be coupled to a reference potential.

[0022] In order to solve the above problems, a power module assembly is also proposed, which includes a packaged integrated power semiconductor device and a heat sink as described above, wherein the heat sink is bonded to the packaged integrated power semiconductor device, and wherein the heat sink is coupled to the packaged integrated power semiconductor device via an electrically insulating and thermally conductive interface.

[0023] In order to solve the above-mentioned problem, a method for measuring the current in a packaged integrated power semiconductor device is also proposed, the packaged integrated power semiconductor device comprising at least one power transistor coupled to a current path, a current measuring device and a package, wherein the current measuring device is electrically insulated from the current path and magnetically coupled to the current path, wherein the current path and the current measuring device are arranged so that the current measuring device can sense the magnetic field of the current flowing through the current path, and wherein at least one power transistor, the current measuring device and the current path are arranged inside the package, wherein the method comprises the following steps: operating at least one power transistor; measuring the current flowing through the current path using the current measuring device; and providing a signal representing the measured current as an output of the packaged integrated power semiconductor device using the current measuring device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present disclosure can be easily understood from the following detailed description taken in conjunction with the accompanying drawings.

[0025] Figure 1A , Figure 1B and Figure 1C An exemplary block diagram of a package-integrated power semiconductor device with an integrated current measuring device according to an embodiment of the present invention is shown.

[0026] Figure 2A , Figure 2B and Figure 2C An exemplary block diagram of a package-integrated power semiconductor device with an integrated current measuring device according to an embodiment of the present invention is shown.

[0027] Figure 3A and Figure 3B A circuit diagram of a half-bridge with an integrated current measuring device according to an embodiment of the present invention is shown.

[0028] Figure 4A and Figure 4B A layout diagram of the circuit of FIG. 3 is shown according to an embodiment of the present invention.

[0029] Figure 5A and Figure 5B A detailed view of a portion of the layout diagram of FIG. 4 is shown in accordance with an embodiment of the present invention.

[0030] Figure 6 A cross-sectional view along line VV in FIG. 5 is shown according to an embodiment of the present invention.

[0031] Fig. 7A and Figure 7B A circuit diagram of a boost converter with an integrated current measuring device according to an embodiment of the present invention is shown.

[0032] Fig. 8A and Figure 8B A circuit diagram of a buck converter with an integrated current measuring device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0033] Reference will now be made in detail to the exemplary embodiments shown in the accompanying drawings. Although the exemplary embodiments will be described with specific details, it will be understood that the exemplary embodiments can be practiced without these specific details. In addition, the following description of the exemplary embodiments is not intended to limit the present application to the exemplary embodiments. On the contrary, the present application will be interpreted as covering all alternatives, modifications and equivalents that may be included within the scope of the described embodiments defined by the appended claims. In addition, the features described with respect to one embodiment may be combined with the features of other embodiments, even if such a combination of features is not explicitly described herein.

[0034] In the accompanying drawings, similar reference numerals represent similar structural elements. In order to avoid unnecessary repetition, repeated descriptions of elements with similar reference numerals are omitted. Therefore, the descriptions provided for structural elements with similar reference numerals are applicable to all corresponding structural elements.

[0035] For purposes of describing the present invention, when an element is described as being “connected” or “coupled” to another element, such description is intended to include both a direct connection ie without any intervening elements and an indirect connection ie with any number of intervening elements, unless otherwise specified.

[0036] Figure 1A An exemplary block diagram of a package-integrated power semiconductor device 10 is shown, which includes a power transistor 14, a current measuring device 16, and a package 17. In order to interface with other devices, the package-integrated power semiconductor device 10 also includes an input terminal 11 and two output terminals 12 and 13. The power transistor 14 is coupled to the output terminal 12 through a current path 15. In addition, the power transistor 14 is coupled to the input terminal 11. The current measuring device 16 is coupled to the output terminal 13.

[0037] The power transistor 14, the current measuring device 16 and the current path 15, as well as the path between the input terminal 11 and the power transistor 14 and the path between the current measuring device 16 and the output terminal 13 are arranged inside the package 17. Therefore, the power semiconductor device 10 is called package-integrated because all elements of the power semiconductor device 10 are arranged inside the package. In the context of the present invention, being arranged inside the package 17 means that all sides of all elements of the package-integrated power semiconductor device 10 are generally covered by the package 17. However, in some embodiments, one or more sides of some elements may not be covered by the package 17. An uncovered side of an element may be used to provide a heat exchange interface between an element of the package-integrated power semiconductor device 10 and a component outside the package-integrated power semiconductor device 10, such as a heat sink. Therefore, in some embodiments of the present invention, at least one side of an element of the integrated packaged power semiconductor device 10 may not be covered by the package 17.

[0038] The package 17 may be made of any material that provides electrical insulation between elements of the package-integrated power semiconductor device 10 and between the package-integrated power semiconductor device 10 and the exterior of the package-integrated power semiconductor device 10. In one example, the package 17 may be a plastic, such as a thermosetting polymer, molded over the elements of the package-integrated power semiconductor device 10.

[0039] The power transistor 14 may be any transistor commonly used in the art to handle high currents (up to tens or hundreds of amperes) and / or high voltages (up to tens, hundreds or thousands of volts), such as an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET) (e.g., a Si MOSFET or a SiC MOSFET), an enhancement mode GaN field effect transistor (eGaNFET), or a high electron mobility transistor (HEMT). Therefore, it should be understood that any particular type of power transistor shown in the drawings may be easily replaced by another type of power transistor.

[0040] although Figure 1A Only a single power transistor is shown, but the package-integrated power semiconductor device 10 may include any number of power transistors, and Figure 1A The single power transistor 14 in is only an example. Similarly, Figure 1A The numbers of input terminals and output terminals of the packaged integrated power semiconductor device 10 shown are only examples, because the numbers of output terminals and input terminals of the packaged integrated power semiconductor device 10 also depend on other factors such as the number of power transistors in the packaged integrated power semiconductor device 10 .

[0041] The current measuring device 16 may be any device configured to provide a signal indicative of the current flowing through the current path 15 based on sensing the magnetic field generated by the current. In order to ensure that the current measuring device 16 provides a signal indicative of the current flowing through the current path 15, the current measuring device 16 is electrically insulated from the current path 15 and magnetically coupled to the current path 15. To this end, the current path 15 and the current measuring device 16 are arranged such that the current measuring device 16 can sense the magnetic field of the current flowing through the current path 15. Figure 1A In the example of the embodiment of the present invention, such arrangement is achieved by arranging the current path 15 to at least partially surround the current measuring device 16. In order to sense the magnetic field, in some embodiments, the current measuring device 16 may include a sensor element configured to detect the magnetic field generated by the current flowing through the current path 15. Examples of such sensor elements include, but are not limited to, Hall effect sensors, fluxgate sensors, or magnetoresistive current sensors.

[0042] Different types of current measuring devices may require different arrangements of the current path. In one example, the current path partially surrounds the current measuring device by surrounding it on three sides. Figure 1AIn the example of, in order to sense the magnetic field generated by the current flowing through the current path 15, the current path 15 includes a U-shaped portion in which a current measuring device 16 is arranged. It should be understood that the current path of the integrated packaged power semiconductor device of the present invention can be arranged according to the needs of the specific type of current measuring device used so that the corresponding type of current measuring device can be electrically insulated from the current path and magnetically coupled to the current path. Other goals of the arrangement of the current path may include adjusting a certain measurement range of the current measuring device or ensuring that it is not affected by interfering background signals (for example, ambient magnetic fields or other noise caused by the operation of the integrated packaged power semiconductor device). The specific arrangements discussed in the specification and shown in the drawings are exemplary only.

[0043] It should be noted that the current flowing through the current path 15 may be a direct current or an alternating current, depending on the corresponding application or operating conditions of the packaged integrated power semiconductor device 10 .

[0044] exist Figure 1A In the example, the current path 15 couples the power transistor 14 to the output terminal 12, so the current measuring device 16 measures the output current of the power transistor 14. In another example, Figure 1B FIG. 1 shows a package-integrated power semiconductor device 10 in which a current path 15 couples an input terminal 11 to a power transistor 14. Figure 1B In the exemplary package-integrated power semiconductor device 10 , the current measuring device 16 measures the input current of the power transistor 14 . Figure 1C The packaged integrated power semiconductor device 10 is shown to include two current measuring devices 16a and 16b with corresponding current paths 15a and 15b and corresponding output pins 13a and 13b. Figure 1C In the exemplary packaged integrated power semiconductor device 10, both the input current and the output current of the power transistor 14 are measured. Therefore, it is clear to those skilled in the art that any number of current measurement devices may be included in the packaged integrated power semiconductor device 10, depending on the number of power transistors and current paths that require current measurement.

[0045] FIG. 2A to FIG. 2C Shows the above discussion Figures 1A to 1C An exemplary block diagram of a package-integrated power semiconductor device 10 corresponding to an exemplary block diagram of FIG. FIG. 2A to FIG. 2C Another example of an arrangement of the current measuring device 16 and the current path 15 is shown, which enables the current measuring device 16 to sense the magnetic field of the current flowing through the current path 15. FIG. 2A to FIG. 2CIn the exemplary arrangement of , the current measuring device 16 is arranged to extend along the length of the current path 15. The length along which the current measuring device 16 extends may depend on various factors, such as the sensing requirements of the particular type of current measuring device used, the sensitivity of the particular type of current measuring device used, or the sensing resolution required for the application using the package-integrated power semiconductor device 10, such as one tenth of an ampere or one hundredth of an ampere. It should also be noted that FIG. 2A to FIG. 2C The length shown is merely an example and is not intended to imply a necessary length or a ratio of the length to the length of the current path 15 .

[0046] The power semiconductor device 10 may be used according to the requirements of the corresponding application of the packaged integrated power semiconductor device 10. Figures 1A to 1C and FIG. 2A to FIG. 2C The two exemplary arrangements of the current path 15 and the current measuring device 16 are shown to enable the current measuring device 16 to sense the magnetic field of the current flowing through the current path 15. These two exemplary arrangements can also be used simultaneously in the package-integrated power semiconductor device 10. For example, in Figure 1C and Figure 2C In the block diagram of , one of the two arrangements of the current path 15a and the current measuring device 16a and the current path 15b and the current measuring device 16b can be replaced by a corresponding other exemplary arrangement. In addition, it is clear to those skilled in the art that, depending on the type of the current measuring device, other arrangements of the current path and the current measuring device can be used as long as these arrangements can sense the magnetic field of the current flowing through the current path while ensuring electrical insulation from the current path and being unaffected by any noise caused by the operation of the package-integrated power semiconductor device.

[0047] Figure 3A and Figure 3B Two power transistors 14 are shown having a half bridge. 1 and 14 2 FIG. 1 is a circuit diagram of an exemplary packaged integrated power semiconductor device 10. Figures 1A to 1C In addition to the components discussed, Figure 3A and Figure 3B The packaged integrated power semiconductor device 10 further includes two freewheeling diodes D 1 and D 2 , provide the corresponding reference potential V DC 、V SS and GND to connect the input terminal V DC 、V SS and GND and various components of the current measurement device 16, which will be discussed in more detail below. In some embodiments, the freewheeling diode D 1 and D 2 can be integrated in the corresponding power transistor 141 and 14 2 In some embodiments, if the freewheeling diode D 1 and D 2 If this is not necessary for the type of application using the package-integrated power semiconductor device 10, the freewheeling diode D may be omitted. 1 and D 2 .

[0048] exist Figure 3A and Figure 3B In the example, the power transistor 14 1 and 14 2 is shown as an IGBT. However, as mentioned above Figure 1A As discussed, any other suitable power transistor type may be used, such as a power MOSFET. 1 and 14 2 The gate is coupled to the input terminal 11 of the packaged integrated power semiconductor device 10 1 and 11 2 In addition, the power transistor 14 1 and 14 2 Both with their respective freewheeling diodes D 1 and D 2 Parallel coupling. Input terminal V DC and V SS are respectively coupled to the power transistor 14 1 and power transistor 14 2 The collector of the power transistor 14 1 and power transistor 14 2 The emitter of the power transistor 14 is coupled to the current path 15. Therefore, the current path 15 is coupled to the 1 and 14 2 Output node of the implemented half-bridge.

[0049] According to about Figures 1A to 1C The exemplary arrangement discussed is arranged Figure 3A The current path 15 and the current measuring device 16 are arranged in the embodiment of the present invention. Therefore, the current path 15 is arranged to at least partially surround the current measuring device 16. Figure 3A In the example of , the current path 15 comprises a U-shaped portion in which the current measuring device 16 is arranged. Figure 3B In, according to FIG. 2A to FIG. 2C The exemplary arrangement discussed is used to arrange the current path 15 and the current measuring device 16. Therefore, Figure 3B The current measuring device 16 is arranged to extend along the length of the current path 15. Figure 3Aand Figure 3B The current path 15 is coupled to the power transistor 14. 1 and 14 2 Between the output node of the realized half-bridge and the output terminal 12 , the current measuring device 16 therefore provides a signal indicative of the output current of the half-bridge.

[0050] Figure 3A and 3B The current measuring device 16 in the embodiment comprises four magnetoresistive elements 16 arranged in an H-bridge configuration. 1 Up to 16 4 As shown by the arrows on all four magnetoresistive elements of the current measuring device 16, the magnetoresistive element 16 1 Up to 16 4 Their resistance is changed in the presence of a magnetic field, such as that generated by a current flowing through the current path 15 .

[0051] exist Figure 3A and Figure 3B In the example of FIG. 1 , the current measuring device 16 comprises four magnetoresistive elements 16 arranged in an H-bridge. 1 Up to 16 4 , to compensate for nonlinearities or changes in the resistor that may be caused, for example, by temperature changes or by other disturbances. In addition to compensating the magnetoresistive element 16 1 Up to 16 4 In addition to the nonlinearity or variation of the current measurement device 16, this H-bridge arrangement also enables the current measurement device 16 to compensate for input disturbances, such as common-mode magnetic fields in the background or other magnetic noise caused by the operation of the packaged integrated power semiconductor device 10. Each half bridge is coupled to a reference potential via the input terminal GND. The reference potential can be, for example, the system ground. Instead of the input terminal GND, each half bridge can also be coupled to the input terminal V ss The outputs of the two half bridges are respectively provided to the operational amplifier 16 of the current measuring device 16 5 The inverting input and non-inverting input.

[0052] Although Figure 3A and Figure 3B The current measuring device 16 is shown to include four magnetoresistive elements to compensate for input variations or variations in the magnetoresistive elements, but in some embodiments such compensation may not be required and the current measuring device may include two magnetoresistive elements in a half-bridge configuration or even only one magnetoresistive element. In these configurations, the operational amplifier 16 5 May be omitted or may be replaced by other components to evaluate the value of one or more magnetoresistive elements. Operational amplifier 16 5 It may be replaced or supplemented by other means or combinations of analog or digital signal processing such as filtering, instrumentation amplifiers, or analog-to-digital converters (ADCs).

[0053] Therefore, depending on the configuration adopted, operational amplifier 16 5 The output signal of the operational amplifier 16 5 The processed output of the current measuring device 16, the output of a single half-bridge or the output of a single magnetoresistive element indicates the current flowing through the current path 15 due to the change in resistance of the magnetoresistive element of the current measuring device 16. Therefore, the corresponding output terminal providing a signal indicating the current flowing through the current path 15 is coupled to the output terminal 13.

[0054] It should be understood that the configuration of the magnetoresistive current sensor discussed above is exemplary only. Other configurations of magnetoresistive current sensors may be used to implement the current measurement device 16 .

[0055] As shown by the dashed line between the current measuring device 16 and the current path 15, in some examples of the present invention, the current measuring device 16 may include a metal shielding path 16S to electrically decouple the current measuring device 16 from the current path 15, for example, to protect the current measuring device 16 from voltage changes in the current path 15. In some examples of the present invention, the metal shielding path 16S may be connected via the input terminal GND or via the input terminal V ss Coupled to the reference potential.

[0056] Figure 4A and Figure 4B Shows Figure 3A and Figure 3B FIG. 1 is a layout diagram of a packaged integrated power semiconductor device 10. Figure 4A In the embodiment, the current path 15 is arranged to at least partially surround the current measuring device 16. Figure 4B In FIG. 1 , the current measuring device 16 is arranged to extend along the length of the current path 15 . Figure 4A and Figure 4B As can be seen from the layout diagram, the input terminal 11 1 , 11 2 、V DC and V ss And the output terminals 12 and 13 may be formed by a plurality of pins. Figure 4A and Figure 4B In the example layout, the power transistor 14 1 、Power transistor 14 2 and the current measuring device 16 are arranged on separate die pads 14 1 P, 14 2 P and 16P to enable the power transistor 14 1 、Power transistor 14 2 The freewheeling diode D is electrically insulated from the current measuring device 16 in order to ensure correct measurement of the magnetic field of the current flowing through the current path 15.1 and D 2 In the embodiment, the diode D 1 and D 2 The power transistor 14 is also arranged 1 and 14 2 The corresponding die pad 14 1 P and 14 2 P.

[0057] The die pad 16P of the current measuring device 16 may be coupled to a reference potential via a pin of the die pad 16P extending to Figure 4A and Figure 4B The current measuring device 16 and the current path 15 are further electrically insulated from the package 17 of the power semiconductor device 10 integrated in the package.

[0058] exist Figure 4A and Figure 4B In the example of FIG. 1 , the packaged integrated power semiconductor device 10 includes a bonding wire 18 that connects the power transistor 14 to the power transistor 14. 1 、Power transistor 14 2 The die pads of the current measuring device 16 are coupled to different input and output terminals. The bonding wires 18 can also couple the power transistor 14 1 and power transistor 14 2 The die pads of the power transistor 14 are coupled to each other to form 1 and 14 2 Output node of the implemented half bridge. Those skilled in the art will readily appreciate that other means for coupling different die pads to each other and to the input and output of the package-integrated power semiconductor device 10 may be used in place of the bond wires 18 .

[0059] Figure 4A and Figure 4B The package 17 in the embodiment is arranged around different die pads, around current paths, and between the die pads and current paths. In particular, Figure 4A and Figure 4BThe package 17 in the embodiment is arranged between the current path 15 and the current measuring device 16 to provide electrical insulation between the current path 15 and the current measuring device 16. In order to achieve electrical insulation, the package 17 includes an electrically insulating mold material that is molded on all elements of the package-integrated power semiconductor device 10 and thus also fills the gap between the current path 15 and the die pad 16P of the current measuring device 16. Therefore, the mold material of the package 17 provides electrical insulation between the current path 15 and the current measuring device 16. At the same time, the mold material is permeable to the magnetic field generated by the current flowing through the current path 15, thereby enabling the current measuring device 16 to be magnetically coupled to the current path 15.

[0060] Figure 5A and Figure 5B Provided in Figure 4A and Figure 4B A more detailed view of an exemplary arrangement of the current path 15 and the current measuring device is shown in FIG. Figure 5A In FIG. 1 , the current path 15 partially surrounds the current measuring device 16 and the die pad 16P. Figure 5B In the embodiment, the current measuring device 16 extends along the length of the current path 15. Specifically, Figure 4A and Figure 4B The more detailed view provided shows that in some embodiments the encapsulation 17 can fill the gap between the die pad 16P of the current measurement device 16 and the current path 15 to provide further electrical insulation therebetween. Figure 5A and Figure 5B A metal shielding path 16S is shown disposed on the die pad 16P to surround the current measuring device 16. In some embodiments, the metal shielding path 16S may include at least one opening on a side of the metal shielding path 16S opposite to the current path 15, such as Figure 5A and Figure 5B As shown. Metal shield path 16S can be coupled to a reference potential via to further improve the electrical insulation between current measurement device 16 and current path 15 provided by metal shield path 16S. For example, coupling to a reference potential can be achieved by coupling the metal shield path to die pad 16P, which in turn can be coupled to GND or another reference potential via a pin of die pad 16P. Additionally or alternatively, output terminal 13 can include a reference voltage pin that can be coupled to metal shield path 16S.

[0061] Figure 6 Shown along Figure 5A The line VV shown Figure 5A. It can be seen in the cross-sectional view that, in some embodiments of the present invention, the current path 15 and the die pad 16P of the current measuring device 16 may be arranged on a thermally conductive insulator 19. The thermally conductive insulator 19 provides a thermal interface for the heat sink 20 so that the heat generated during the operation of the integrated packaged power semiconductor device 10 can be dissipated. In addition, since the thermally conductive insulator 19 is electrically insulating, the thermally conductive insulator 19 can prevent leakage current between the current path 15 and the die pad 16P of the current measuring device, and thus the thermally conductive insulator 19 can provide insulation between the current path 15 and the current measuring device 16. In some embodiments, the thermally conductive insulator 19 may include an inorganic material including SiO 2 、Al 2 O 3 、AlN、Si 3 N 4 In addition to or in place of these materials, other potting materials, such as silicone gel, may be used.

[0062] although Figure 6 Shown along Figure 5A , and thus shows the current path 15 on both sides of the current measuring device 16, but from the previous description, it is clear to those skilled in the art that Figure 5B A cross-sectional view will in principle show Figure 5A The same arrangement, with the only difference being that the current path 15 will only be shown on one side of the current measuring device 16 .

[0063] In some embodiments of the present invention, the entire packaged integrated power semiconductor device 10 may be disposed on the thermally conductive insulator 19. In some embodiments, only certain portions of the packaged integrated power semiconductor device 10, such as the die pad 14, may be disposed on the thermally conductive insulator 19. 1 P, 14 2 P and 16P and current path 15 are arranged on thermally conductive insulator 19. In some embodiments, thermally conductive insulator 19 may be omitted and package 17 covers all sides of all elements of package-integrated power semiconductor device 10.

[0064] Fig. 7A and Figure 7B FIG. 1 is a circuit diagram of a packaged integrated power semiconductor device 10 for implementing a boost converter. In this example, the packaged integrated power semiconductor device 10 includes a power transistor 14, and a current path 15 is coupled between the input terminal 11 and the emitter of the power transistor 14 and the diode D 1 between the anodes. Therefore, Fig. 7A and Figure 7BThe exemplary packaged integrated power semiconductor devices 10 correspond to Figure 1B and Figure 2B The packaged integrated power semiconductor device 10, in Figure 1B and Figure 2B In the embodiment of the present invention, a current measuring device 16 inside the package-integrated power semiconductor device 10 is used to provide a signal indicative of the input current.

[0065] Fig. 8A and Figure 8B FIG. 1 shows a circuit diagram of a packaged integrated power semiconductor device 10 for implementing a buck converter. In this example, the packaged integrated power semiconductor device 10 includes a power transistor 14, and a current path 15 is coupled between the collector of the power transistor 14 and the diode D 1 between the cathode and the output terminal 12. Therefore, Fig. 8A and Figure 8B The packaged integrated power semiconductor devices 10 correspond to Figure 1A and Figure 2A The packaged integrated power semiconductor device 10. Therefore, Fig. 8A and Figure 8B An exemplary circuit implemented by a package-integrated power semiconductor device according to the present invention is shown, the circuit including a single power transistor 14 and using a current measurement device 16 inside the package-integrated power semiconductor device 10 to provide a signal indicative of the output current.

[0066] Figure 3A and Figure 3B , Fig. 7A and Figure 7B and Fig. 8A and Figure 8B Examples of possible power circuits are provided that can be implemented in a power semiconductor device according to an integrated package of the present invention. It will be appreciated by those skilled in the art that any possible power circuit including any number of power transistors required for each circuit can be implemented in a power semiconductor device according to an integrated package of the present invention.

[0067] In addition, it should be understood that the various measures disclosed in the present application for achieving electrical insulation between the current measuring device and the current path while allowing magnetic coupling between the current measuring device and the current path inside the package of the integrated packaged power semiconductor device of the present invention can be adopted individually or in any combination guaranteed by the corresponding specifications of the circuit to be implemented in the integrated packaged power semiconductor device of the present invention. In addition, the measures for achieving electrical insulation between the current measuring device and the current path of the integrated packaged power semiconductor device of the present invention are not limited to those explicitly disclosed in the previous detailed description. Instead, it will be clear to those skilled in the art that the measures explicitly disclosed in the previous detailed description for achieving electrical insulation between the current measuring device and the current path while allowing magnetic coupling between the current measuring device and the current path, as well as other measures or combinations of measures that are not explicitly disclosed, are intended to be covered by the scope of the attached claims and their legal equivalents.

Claims

1. A packaged integrated power semiconductor device, comprising: at least one power transistor coupled to the current path; Current measuring device; at least one gap formed laterally between the current measuring device and the current path; as well as Package, wherein the current measuring device is electrically insulated from the current path and magnetically coupled to the current path, wherein the current path and the current measuring device are arranged such that the current measuring device can sense the magnetic field of the current flowing through the current path, wherein the at least one power transistor, the current measuring device and the current path are arranged inside the package, wherein the package comprises an electrically insulating molding material arranged on the at least one power transistor, the current measuring device and the current path, wherein the electrically insulating molding material provides electrical insulation between the current measuring device and the current path, and The electrically insulating molding material fills the at least one gap between the current measuring device and the current path.

2. The packaged integrated power semiconductor device according to claim 1, wherein: The current measuring device is arranged to extend along the length of the current path.

3. The packaged integrated power semiconductor device according to claim 1, wherein: The current path is arranged at least partially around the current measuring device.

4. The packaged integrated power semiconductor device according to claim 3, wherein: The current path is arranged to at least partially surround the current measuring device on three sides.

5. The packaged integrated power semiconductor device according to claim 3 or 4, wherein: A portion of the current path is U-shaped and has an inner space defined by the U-shape, and wherein the current measuring device is arranged within the inner space of the U-shaped portion of the current path.

6. The packaged integrated power semiconductor device according to any one of claims 1 to 4, wherein: The at least one power transistor and the current measuring device are arranged on separate die pads.

7. The packaged integrated power semiconductor device according to any one of claims 1 to 4, further comprising a thermally conductive electrical insulator, wherein: The package, the at least one power transistor, the current measuring device and the current path are arranged on the thermally conductive electrical insulator and are inserted between the thermally conductive electrical insulator and the electrically insulating molding material.

8. The packaged integrated power semiconductor device according to claim 7, wherein: The thermally conductive electrical insulator comprises an inorganic material, and the inorganic material comprises at least one of the following materials: SiO2, Al2O3, AlN and Si3N4.

9. The packaged integrated power semiconductor device according to claim 7, wherein: The electrically insulating molding material is arranged in contact with the current measuring device and the current path, and is also arranged in contact with the thermally conductive electrical insulator at the at least one gap.

10. The packaged integrated power semiconductor device according to any one of claims 1 to 4, wherein: The current measurement device includes a sensor element configured to detect a magnetic field generated by a current flowing through the current path.

11. The packaged integrated power semiconductor device according to claim 10, wherein: The sensor element comprises at least two magnetoresistive elements.

12. The packaged integrated power semiconductor device according to claim 11, wherein: The at least one power transistor and the current measuring device are arranged on separate die pads, wherein the at least two magnetoresistive elements are arranged on two opposite sides of the die pad, and wherein one of the two opposite sides is the side closest to the current path and the other of the two opposite sides is parallel to the one side.

13. The packaged integrated power semiconductor device according to any one of claims 1 to 4, wherein: The current measuring device comprises a metal shielding path, and wherein the metal shielding path at least partially surrounds the current measuring device.

14. The packaged integrated power semiconductor device according to any one of claims 1 to 4, wherein: The electrically insulating molding material has a shape conforming to the current measuring device, the current path and the at least one gap.

15. A power module assembly, comprising: The packaged integrated power semiconductor device according to any one of claims 1 to 14; as well as heat sink; and An electrically insulating and thermally conductive interface couples the packaged integrated power semiconductor device to the heat sink such that the heat sink is bonded to the packaged integrated power semiconductor device.

16. A method for measuring current in a packaged integrated power semiconductor device according to any one of claims 1 to 14, the method comprising the following steps: operating the at least one power transistor; measuring the current flowing through the current path using the current measuring device; as well as A signal representing the measured current is provided as an output of the package-integrated power semiconductor device by means of the current measuring device.

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