Intelligent power module

Abstract

The utility model provides an intelligent power module. A first substrate, a second substrate, a capacitance isolation drive circuit module and a power circuit module are arranged in the intelligent power module. The capacitance isolation driving circuit module is arranged on the first substrate, the power circuit module is arranged on the second substrate, and the first substrate is electrically connected with the power circuit module; wherein; and the capacitance isolation driving circuit module is used for receiving an external control signal and sending an internal control signal corresponding to the external control signal to the power circuit module. The isolation driving circuit is integrated in the intelligent power module, so that the isolation requirement of electrical safety can be met, the system integration degree is improved, the overall parasitic inductance is reduced, meanwhile, the isolation driving circuit is arranged on the first substrate, the arrangement of leads in the intelligent power module can be reduced, common-mode interference is reduced, and the service life of the intelligent power module is prolonged. The reliability of the intelligent power module is improved, and on the basis, setting of higher voltage and frequency can be achieved.

Description

Technical Field

[0001] This utility model relates to the field of electronic devices, and in particular to an intelligent power module. Background Technology

[0002] An IPM (Intelligent Power Module) is a multi-chip structure module that encapsulates power device chips and protection driver chips or circuits within the same insulator. With the development of power semiconductor technology, the power that IPMs can handle is gradually increasing. The voltage and switching frequency that traditional silicon-based chips can withstand are no longer sufficient to meet the growing demands. However, with the development of silicon carbide (SiC), a third-generation semiconductor material capable of withstanding higher voltages and frequencies, SiC discrete devices and integrated power modules are already being used in home appliances, new energy vehicles, and other fields.

[0003] However, for IPMs that integrate drive and protection functions into the same module, reliability issues such as common-mode interference and lack of electrical isolation limit the IPM's ability to achieve higher voltage and higher frequency specifications. Utility Model Content

[0004] The main purpose of this invention is to propose an intelligent power module, which aims to solve the problem that the reliability of existing IPMs prevents the application of higher voltage and higher frequency specifications.

[0005] To achieve the above objectives, this utility model provides an intelligent power module, which includes a first substrate, a second substrate, a capacitor-isolated drive circuit module, and a power circuit module. The capacitor-isolated drive circuit module is disposed on the first substrate, and the power circuit module is disposed on the second substrate. The first substrate and the power circuit module are electrically connected.

[0006] The capacitor-isolated drive circuit module is used to receive external control signals, and after capacitively isolating the drive side receiving the external control signals from the power side where the power circuit module is located, it sends the internal control signal corresponding to the external control signal to the power circuit module.

[0007] Optionally, the first substrate is a printed circuit board, and the second substrate is a ceramic copper-clad laminate.

[0008] Optionally, the capacitor isolation drive circuit module includes an isolation unit and a signal output unit, and the power circuit module includes multiple power devices, with the signal output unit connected to each power device in a one-to-one correspondence; wherein:

[0009] One set of output terminals of the isolation unit is connected to one of the signal output units.

[0010] Optionally, the isolation unit includes a processing chip and a capacitor subunit; the capacitor subunit includes multiple capacitor components, and the output terminal of the capacitor components serves as the output terminal of the isolation unit.

[0011] The output terminals of the processing chip are connected one-to-one with the input terminals of the capacitor assembly; wherein:

[0012] The processing chip is used to receive external control signals, convert the external control signals into alternating current and output them to the capacitor assembly, so that the capacitor assembly outputs the corresponding internal control signals.

[0013] Optionally, the capacitor assembly includes an isolation capacitor and a drive output chip; wherein:

[0014] The first terminal of the isolation capacitor is connected to a set of output terminals of the processing chip, and the second terminal of the isolation capacitor is connected to the input terminal of the drive output chip, wherein the output terminal of the drive output chip serves as the output terminal of the capacitor assembly; wherein:

[0015] The drive output chip is used to convert the signal received through the isolation capacitor into DC power to obtain the internal control signal, and send the internal control signal to the corresponding power device.

[0016] Optionally, the isolation capacitor includes a first metal electrode, a second metal electrode, a third metal electrode, and a fourth metal electrode; an insulating material is filled between the first metal electrode and the second metal electrode, and an insulating material is filled between the third metal electrode and the fourth metal electrode; wherein:

[0017] The first metal electrode is connected to the output terminal of the processing chip, the second metal electrode is electrically connected to the third metal electrode, and the fourth metal electrode is connected to the input terminal of the drive output chip.

[0018] Optionally, a modulator is provided within the processing chip, and a demodulator is provided within the drive output chip; wherein:

[0019] The processing chip is used to convert the external control signal into alternating current, and modulate the alternating current to a preset frequency through the modulator before outputting it to the capacitor assembly, so that the capacitor assembly outputs the corresponding internal control signal.

[0020] The drive output chip is used to demodulate the internal control signal through the demodulator and convert the demodulated signal into DC power.

[0021] Optionally, a set of output terminals of the isolation unit includes a signal output terminal; the signal output unit includes a first resistor; wherein:

[0022] The first resistor is connected between the signal output terminal of the isolation unit and the gate of the power device.

[0023] Optionally, the signal output unit further includes a second resistor and a first diode; wherein:

[0024] The negative terminal of the first diode is connected to the signal output terminal of the isolation unit, the positive terminal of the first diode is connected to the first terminal of the second resistor, and the second terminal of the second resistor is connected to the gate of the power device.

[0025] Optionally, the isolation unit includes an upper transistor output terminal, which includes an upper transistor high-voltage terminal and an upper transistor ground terminal; the signal output unit includes a negative voltage drive subunit, which includes a first capacitor, a second capacitor, a first Zener diode, and a third resistor; wherein:

[0026] The positive terminal of the Zener diode is connected to the ground terminal of the isolation unit, the negative terminal of the Zener diode is connected to the source terminal of the power device, the negative terminal of the Zener diode is also connected to the first terminal of the third resistor, the second terminal of the third resistor is connected to the high-voltage terminal of the isolation unit, the first capacitor is connected in parallel with the third resistor, and the second capacitor is connected in parallel with the Zener diode.

[0027] Optionally, the isolation unit includes an upper transistor output terminal, which includes a high-voltage terminal and a ground terminal of the upper transistor; the capacitor isolation drive circuit module further includes a bootstrap unit, which includes a fourth resistor, a second diode, and a third capacitor; wherein:

[0028] The first end of the fourth resistor is connected to the driving power supply, the second end of the fourth resistor is connected to the positive terminal of the second diode, the negative terminal of the second diode is connected to the high voltage terminal of the upper tube of the isolation unit, the first end of the third capacitor is connected to the high voltage terminal of the upper tube of the isolation unit, and the second end of the third capacitor is connected to the ground terminal of the upper tube of the isolation unit.

[0029] Optionally, the intelligent power module further includes a lead frame; wherein:

[0030] The lead frame is electrically connected to the first substrate, the second substrate, and the power circuit module, respectively, and is used to lead out the electrodes on the first substrate, the second substrate, and the power circuit module to the corresponding pins.

[0031] This invention proposes an intelligent power module, which includes a first substrate, a second substrate, a capacitor-isolated drive circuit module, and a power circuit module. The capacitor-isolated drive circuit module is disposed on the first substrate, and the power circuit module is disposed on the second substrate, with the first substrate and the power circuit module electrically connected. The capacitor-isolated drive circuit module receives external control signals, and after capacitively isolating the drive side receiving the external control signals from the power side where the power circuit module is located, it sends an internal control signal corresponding to the external control signals to the power circuit module. By integrating the isolation drive circuit into the intelligent power module, the electrical safety isolation requirements are met, the system integration is improved, and the overall parasitic inductance is reduced. Furthermore, placing the isolation drive circuit on the first substrate reduces the number of leads within the intelligent power module, lowers common-mode interference, and improves the reliability of the intelligent power module. Based on this, higher voltage and frequency settings can be achieved. Attached Figure Description

[0032] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0033] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0035] Figure 1 This is a module structure diagram of the first embodiment of the intelligent power module of this utility model;

[0036] Figure 2 This is a side sectional view of the intelligent power module of this utility model;

[0037] Figure 3 This is a circuit structure diagram of an embodiment of the intelligent power module of this utility model;

[0038] Figure 4 This is a circuit diagram of another embodiment of the intelligent power module of this utility model;

[0039] Figure 5This is a structural diagram of an embodiment of the capacitor assembly in the intelligent power module of this utility model;

[0040] Figure 6 This is a schematic diagram of the intelligent power module of this utility model;

[0041] Figure 7 This is a schematic diagram of the layout structure of the intelligent power module of this utility model.

[0042] Explanation of icon numbers:

[0043]

[0044] Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0046] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0047] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention. To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0048] This utility model provides an intelligent power module, referring to... Figure 1 , Figure 1This is a structural diagram of the first embodiment of the intelligent power module of this utility model. The intelligent power module includes a first substrate 100, a second substrate 200, a capacitor isolation drive circuit module 300, and a power circuit module 400. The capacitor isolation drive circuit module 300 is disposed on the first substrate 100, and the power circuit module 400 is disposed on the second substrate 200. The first substrate 100 and the power circuit module 400 are electrically connected.

[0049] The capacitor-isolated drive circuit module 300 is used to receive external control signals, and after capacitively isolating the drive side receiving the external control signals from the power side where the power circuit module is located, it sends the internal control signal corresponding to the external control signals to the power circuit module 400.

[0050] The capacitor-isolated drive circuit module 300 is used to achieve electrical isolation within the intelligent power module through capacitors.

[0051] The capacitor-isolated drive circuit module 300 includes capacitor-isolated drive devices, and the specific device type can be set according to actual needs.

[0052] The power circuit module 400 is used to perform the power drive function of the intelligent power module.

[0053] The power circuit module 400 includes power switching devices, and the specific type and structure of the power switching devices can be set according to actual needs.

[0054] The external control signal is a control signal sent by an external controller connected to the intelligent power module. It can be understood that the external control signal is sent from the external controller to the intelligent power module. The capacitor isolation drive circuit module 300 in the intelligent power module receives the external control signal and performs capacitor isolation on the external control signal. At the same time, it outputs an internal control signal corresponding to the external control signal to the power circuit module 400. The power circuit module 400 executes the switching action corresponding to the external control signal based on the control of the internal control signal, and then outputs power based on the executed switching action.

[0055] For silicon carbide smart power modules operating in high-voltage, high-frequency environments, the capacitance to ground generates common-mode current flowing through the signal path. Simultaneously, impedance asymmetry creates differential-mode voltage interference, both of which can cause malfunctions in the power circuit module 400. By incorporating a capacitor-isolated drive circuit module 300, electrical isolation between the drive side receiving external control signals and the power side where the power circuit module 400 is located improves anti-interference capabilities and reduces common-mode interference. Furthermore, integrating the capacitor-isolated drive circuit module 300 within the smart power module, rather than placing it in an external circuit, increases the overall system integration, reduces parasitic effects in high-frequency environments, and enhances overall system safety against accidental electric shock. Therefore, it is possible to achieve silicon carbide smart power modules with higher voltage and frequency specifications.

[0056] Existing smart power modules primarily use lead frames to electrically connect components. However, this method employs numerous bonding wires, resulting in significant parasitic capacitance within the smart power module, which fails to meet the requirements of high-voltage and high-frequency applications. Therefore, in this embodiment, a capacitor-isolated drive circuit module 300 is mounted on a first substrate 100, and a power circuit module 400 is mounted on a second substrate 200. This allows components within the capacitor-isolated drive circuit module 300 to be electrically connected via the first substrate 100, and components within the power circuit module 400 to be electrically connected via the second substrate 200. Consequently, lead frames can be avoided within the smart power module, greatly reducing the use of bonding wires and lowering the parasitic capacitance within the smart power module.

[0057] This embodiment integrates the isolation drive circuit into the intelligent power module, thereby meeting the isolation requirements for electrical safety, improving system integration, and reducing overall parasitic inductance. At the same time, by placing the isolation drive circuit on the first substrate 100, the number of leads inside the intelligent power module can be reduced, common-mode interference can be reduced, and the reliability of the intelligent power module can be improved. On this basis, higher voltage and frequency settings can be achieved.

[0058] Further, see Figure 2 The first substrate 100 is a printed circuit board.

[0059] In this embodiment, the first substrate 100 is a PCB (Printed Circuit Board).

[0060] It is understandable that the circuit structure of the capacitor isolation drive circuit module 300 is relatively complex, and the heat dissipation requirement is relatively low. Therefore, in this embodiment, the first substrate 100 is a PCB, which can reduce the application cost while meeting the requirements of the isolation drive circuit.

[0061] Other components 800 within the capacitor isolation drive circuit module 300 can be connected to the PCB via solder paste 700 through reflow soldering. The chip can be connected to the PCB via conductive silver paste 710, and the electrical connection is completed through the copper foil circuit inside the PCB.

[0062] In other embodiments, the type of the first substrate 100 can be specifically set, such as a ceramic PCB.

[0063] Furthermore, the second substrate 200 is a ceramic copper-clad laminate.

[0064] The power circuit module 400 is composed of power switching devices, so it generates a lot of heat in applications. Therefore, the power circuit module 400 has a high requirement for heat dissipation. At the same time, the structure of the power circuit module 400 is relatively simple. Therefore, in this embodiment, the second substrate 200 is made of DBC (Direct Bond Copper) to meet the heat dissipation requirements of the power circuit module 400.

[0065] In specific configurations, the heat dissipation side of the ceramic copper-clad laminate is placed at the bottom edge of the intelligent power module to improve its heat dissipation capacity.

[0066] The power circuit module 400 can be connected to the ceramic copper-clad laminate via reflow soldering using solder paste 700.

[0067] Further, see Figure 3 The capacitor isolation drive circuit module 300 includes an isolation unit 301 and a signal output unit, and the power circuit module 400 includes a plurality of power devices Q1, with the signal output unit connected to each power device Q1 in a one-to-one correspondence; wherein:

[0068] One set of output terminals of the isolation unit 301 is connected to one of the signal output units.

[0069] The isolation unit 301 is used to electrically isolate the drive side that receives external control signals from the power side where the power device Q1 is located, and to send the internal control signal corresponding to the external control signal to the signal output unit.

[0070] The signal output unit is used to send internal control signals to the gate of power device Q1.

[0071] The specific type of power device Q1 can be set based on actual needs. For example, the material of the power device can be silicon-based or silicon carbide-based, and the type of power device can be MOSFET, IGBT, etc.

[0072] The input terminal of isolation unit 301 is connected to an external controller. Isolation unit 301 includes multiple output terminals for different power devices Q1. Each output terminal is connected to the gate of power device Q1 through a signal output unit. That is, the number of signal output units is the same as the number of power devices Q1, and they are connected one-to-one. The number of power devices Q1 can be set according to the circuit requirements of the actual application. For example, for a half-bridge circuit, two power devices Q1 can be set, and correspondingly, isolation unit 301 can include two output terminals and two corresponding signal output units. For a two-phase bridge, four power devices Q1 can be set, and correspondingly, isolation unit 301 can include four output terminals and four corresponding signal output units. For a three-phase bridge, six power devices Q1 can be set, and correspondingly, isolation unit 301 can include six output terminals and six corresponding signal output units.

[0073] The specific type of power device Q1 can be set based on actual needs. In this embodiment and subsequent embodiments, a silicon carbide MOSFET is used as an example for illustration.

[0074] The isolation unit 301 can specifically adopt an isolation driver chip. The corresponding isolation driver chip can be selected based on the specific settings of the power circuit module 400. For example, when the power circuit module 400 is a half-bridge power module, a dual-channel isolation driver chip can be used; when the power circuit module 400 is a full-bridge power module, a four-channel isolation driver chip or two dual-channel isolation driver chips can be used; when the power circuit module 400 is a three-phase bridge power module, a six-channel driver chip, three dual-channel driver chips, or six single-channel driver chips can be used.

[0075] The isolation unit 301 receives an external control signal sent by an external controller, such as a high / low level signal, and determines the power device Q1 to which the external control signal is targeted. The isolation unit 301 electrically isolates the drive side receiving the external control signal from the power side where the power device Q1 is located, and determines the power device Q1 to which the external control signal is targeted. It then outputs an internal control signal with the same high / low level as the external control signal to the corresponding signal output unit. The signal output unit sends the internal control signal to the gate of the corresponding power device Q1 so that the power device Q1 sets its switching state based on the gate level.

[0076] Further, see Figure 4 The isolation unit includes a processing chip U1 and a capacitor subunit; the capacitor subunit includes multiple capacitor components, and the output terminal of the capacitor components serves as the output terminal of the isolation unit.

[0077] The output terminals of the processing chip U1 are connected one-to-one with the input terminals of the capacitor assembly; wherein:

[0078] The processing chip U1 is used to receive external control signals, convert the external control signals into alternating current and output them to the capacitor assembly, so that the capacitor assembly outputs the corresponding internal control signals.

[0079] The capacitor assembly is connected to the gate of the power device Q1 in a one-to-one correspondence.

[0080] The processing chip U1 receives the external control signal sent by the external controller and determines the power device Q1 to which the external control signal is targeted, and then determines the capacitor component corresponding to the power device Q1; the processing chip U1 modulates the switching signal into an AC signal and sends the AC signal to the corresponding capacitor component, thereby sending the corresponding internal control signal to the gate of the corresponding power device Q1 through the AC-blocking capacitor component; thus achieving electrical isolation.

[0081] Further, see Figure 5 The capacitor assembly includes an isolation capacitor CG and a drive output chip U2; wherein:

[0082] The first terminal of the isolation capacitor CG is connected to a set of output terminals of the processing chip U1, and the second terminal of the isolation capacitor CG is connected to the input terminal of the drive output chip U2. The output terminal of the drive output chip U2 serves as the output terminal of the capacitor assembly; wherein:

[0083] The drive output chip U2 is used to convert the signal received through the isolation capacitor CG into DC power to obtain the internal control signal, and send the internal control signal to the corresponding power device Q1.

[0084] Processing chip U1 receives external control signals sent by an external controller and determines the power device Q1 targeted by the external control signal, and then determines the isolation capacitor CG corresponding to the power device Q1. Processing chip U1 modulates the switching signal into an AC signal based on the external control signal and sends the AC signal to the isolation capacitor CG, thereby sending the AC signal to the drive output chip U2 through the AC-blocking isolation capacitor CG. Drive output chip U2 receives the AC power and demodulates it into a switching signal to output the corresponding high-level signal, i.e., the internal control signal, to the gate of the corresponding power device Q1.

[0085] Further, the isolation capacitor CG includes a first metal electrode P1, a second metal electrode P2, a third metal electrode P3, and a fourth metal electrode P4; the space between the first metal electrode P1 and the second metal electrode P2 is filled with an insulating material, and the space between the third metal electrode P3 and the fourth metal electrode P4 is filled with an insulating material; wherein:

[0086] The first metal electrode P1 is connected to the output terminal of the processing chip U1, the second metal electrode P2 is electrically connected to the third metal electrode P3, and the fourth metal electrode P4 is connected to the input terminal of the drive output chip U2.

[0087] The isolation capacitor CG consists of insulating material within the chip and metal electrodes. The insulating part is typically made of silicon dioxide 900, and it exists on both sides of the isolation chip, working together to provide isolation. It can be understood that the isolation capacitor CG can be considered as the equivalent capacitance formed by the series connection of the capacitors between the processing chip U1 and the drive output chip U2.

[0088] The specific structure of the isolation capacitor CG can be set according to actual needs, as shown in [reference needed]. Figure 5 The isolation capacitor CG can be fabricated using MOS technology, specifically consisting of chip electrodes and internal silicon dioxide 900 material. First, insulation is achieved using silicon dioxide 900, within which metal electrodes are embedded. The first metal electrode is connected to the functional circuit area on one side of the P1 processing chip U1, and the second metal electrode P2 is connected to the metal electrode on the side of the drive output chip U2 via bonding wires. The third metal electrode P3 on the side of the drive output chip U2 is connected to the functional circuit on one side of the drive output chip U2 via silicon dioxide 900 and the fourth metal electrode P4. External control signals are connected to the processing chip U1 via bonding wires and then connected to the drive output chip U2 via the capacitor structure of metal electrode-silicon dioxide 900-metal electrode.

[0089] Furthermore, a modulator is provided within the processing chip U1, and a demodulator is provided within the drive output chip U2; wherein:

[0090] The processing chip U1 is used to convert the external control signal into alternating current, and modulate the alternating current to a preset frequency through the modulator before outputting it to the capacitor assembly, so that the capacitor assembly outputs the corresponding internal control signal.

[0091] The drive output chip U2 is used to demodulate the internal control signal through the demodulator and convert the demodulated signal into DC power.

[0092] Considering that high-frequency interference can also be transmitted through capacitors, this embodiment includes a modulator and demodulator for the capacitor isolation structure. This converts the switching signal to a preset frequency before transmission. The specific value of the preset frequency can be set based on the actual application scenario. Alternatively, two capacitors can be used for differential signal transmission of the modulated signal to improve anti-interference capability.

[0093] Further, see Figure 4The isolation unit 301 includes a set of output terminals, one of which is a signal output terminal; the signal output unit includes a first resistor R1; wherein:

[0094] The first resistor R1 is connected between the signal output terminal of the isolation unit 301 and the gate of the power device Q1.

[0095] When the isolation unit 301 outputs a high-level internal control signal, the internal control signal reaches the gate of the power device Q1 through the first resistor R1, and the gate of the power device Q1 presents a high level.

[0096] When the isolation unit 301 outputs a low-level internal control signal, the internal control signal reaches the gate of the power device Q1 through the first resistor R1, and the gate of the power device Q1 presents a low level.

[0097] Furthermore, the signal output unit also includes a second resistor R2 and a first diode D1; wherein:

[0098] The negative terminal of the first diode D1 is connected to the signal output terminal of the isolation unit 301, the positive terminal of the first diode D1 is connected to the first terminal of the second resistor R2, and the second terminal of the second resistor R2 is connected to the gate of the power device Q1.

[0099] It is understandable that in practical applications, due to circuit interference and other issues, the power device Q1 will oscillate when switching. Therefore, in order to avoid the oscillation from affecting the system operation, this embodiment sets up an oscillation suppression and current limiting circuit composed of the second resistor R2 and the first diode D1, thereby suppressing the oscillation of the power device Q1 when switching.

[0100] Further, the isolation unit 301 includes an upper transistor output terminal, which includes an upper transistor high-voltage terminal and an upper transistor ground terminal; the signal output unit includes a negative voltage driving subunit, which includes a first capacitor C1, a second capacitor C2, a first Zener diode DZ1, and a third resistor R3; wherein:

[0101] The positive terminal of the Zener diode DZ1 is connected to the ground terminal of the isolation unit 301, the negative terminal of the Zener diode DZ1 is connected to the source terminal of the power device Q1, the negative terminal of the Zener diode DZ1 is also connected to the first terminal of the third resistor R3, the second terminal of the third resistor R3 is connected to the high voltage terminal of the isolation unit 301, the first capacitor C1 is connected in parallel with the third resistor R3, and the second capacitor C2 is connected in parallel with the Zener diode DZ1.

[0102] In practical applications, due to circuit interference and other issues, the power device Q1 will oscillate when switching. Therefore, in order to avoid the oscillation from affecting the system operation, this embodiment is provided with a negative voltage drive subunit consisting of a first capacitor C1, a second capacitor C2, a first Zener diode DZ1 and a third resistor R3.

[0103] Specifically, after the high-voltage terminal of the isolation unit 301 outputs voltage, the second capacitor C2 is charged through the third resistor R3. After the voltage of the second capacitor C2 reaches the reverse breakdown voltage of the first Zener diode DZ1, the voltage across the first Zener diode DZ1 stabilizes. At this time, a stable negative voltage is provided to the source of the power device Q1.

[0104] By using a negative voltage drive subunit to improve the reliability of power device Q1 turn-off, the switching speed can be increased, switching losses reduced, parasitic oscillations suppressed, and system stability and reliability improved.

[0105] Further, the isolation unit 301 includes an upper transistor output terminal, which includes an upper transistor high-voltage terminal and an upper transistor ground terminal; the capacitor isolation drive circuit module 300 also includes a bootstrap unit, which includes a fourth resistor R4, a second diode D2, and a third capacitor C3; wherein:

[0106] The first end of the fourth resistor R4 is connected to the driving power supply, the second end of the fourth resistor R4 is connected to the positive terminal of the second diode D2, the negative terminal of the second diode D2 is connected to the high voltage terminal of the upper tube of the isolation unit 301, the first end of the third capacitor C3 is connected to the high voltage terminal of the upper tube of the isolation unit 301, and the second end of the third capacitor C3 is connected to the ground terminal of the upper tube of the isolation unit 301.

[0107] It is understandable that, for the upper transistor of the power switching circuit, after it is turned on, the power supply voltage reaches the source of the power device Q1. At this time, if the gate voltage receives the voltage of the internal control signal and is consistent with the power supply voltage, the gate voltage of the power device Q1 will be consistent with the source voltage, and the power device Q1 will be turned off immediately after being turned on, and cannot maintain the conducting state. Therefore, in order to maintain the conduction of the power device Q1, this embodiment sets up a bootstrap unit composed of the fourth resistor R4, the second diode D2 and the third capacitor C3. The bootstrap unit increases the gate voltage so that after the power device Q1 is turned on, the gate voltage can be guaranteed to be greater than the source voltage, thereby maintaining the conduction of the power device Q1.

[0108] Further, see Figure 2 The intelligent power module further includes a lead frame 500; wherein:

[0109] The lead frame 500 is electrically connected to the first substrate 100, the second substrate 200, and the power circuit module 400, respectively, and is used to lead out the electrodes on the first substrate 100, the second substrate 200, and the power circuit module 400 to the corresponding pins.

[0110] In this embodiment, the internal and external components of the smart power module are connected through the lead frame 500.

[0111] It is understandable that the lead frame 500 here is used for the connection between the internal devices and external pins of the smart power module, rather than for the electrical connection between internal devices. Therefore, the use of the lead frame 500 here will not increase the parasitic capacitance in the smart power module.

[0112] Specifically, the lead frame 500 can be connected to the first substrate 100 and the second substrate 200 respectively through a reflow soldering process using solder paste 700.

[0113] Furthermore, the first substrate 100 is connected to the power circuit module 400 via bonding wire 600.

[0114] For ease of implementation, in this embodiment, the first substrate 100 and the points that need to be connected in the power circuit module 400 are connected by bonding wires 600, thereby realizing the connection between the capacitor isolation drive circuit module 300 and the power circuit module 400.

[0115] The overall manufacturing process of the intelligent power module is described below:

[0116] (1) Dicing: The required chips, such as power devices Q1, diodes, Zener diodes DZ1, drive output chips U2, etc., are cut from the wafer for use in subsequent chip assembly processes.

[0117] (2) Core assembly; First, apply solder paste 700 to the positions where soldering is required using screen printing technology on the PCB substrate and DBC substrate; Place the die, other components 800 (such as resistors and capacitors), and lead frame 500 to the corresponding positions on the DBC substrate and PCB substrate respectively; Then, assemble and bond the DBC substrate, PCB substrate, and lead frame 500 together at the reserved solder paste positions using a fixture.

[0118] (3) Reflow soldering: The assembled structure is reflow soldered so that the solder paste 700 completes the connection of the lead frame 500, DBC substrate, PCB substrate, die, and other components 800.

[0119] (4) Core mounting: Apply conductive silver paste to the corresponding positions on the PCB substrate, place the processing chip U1 and the drive output chip U2 in the corresponding positions on the PCB substrate, and then cure them.

[0120] (5) Wire bonding; For power device Q1, aluminum wire is used to connect the electrodes on its surface to the lead frame 500 to lead out to the corresponding pins; For the parts of other components 800 that need to be bonded, gold wire is used to bond to the PCB substrate.

[0121] (6) Molding; The assembled body that has been bonded above is placed in a molding mold and injection molded with epoxy resin molding compound to form a molding body 331, and then subjected to a post-curing process to ensure that the cross-linking reaction is complete.

[0122] (7) Electroplating and cutting: The outer pin portion of the lead frame 500 is tin-plated to improve solderability, and then the lead frame 500 is cut apart from the part required by the smart power module by stamping process to form a dual in-line package.

[0123] (8) Testing and marking: After passing the electrical performance test, the product information is marked by laser marking to obtain the final intelligent power module.

[0124] See Figure 6 The overall principle of the intelligent power module is explained below:

[0125] The signal input of the external controller is a high-level / low-level signal issued by the control chip, i.e., an external control signal. The capacitor-isolated drive circuit module 300 is an isolated drive chip within the intelligent power module package. The capacitor-isolated drive circuit module 300 receives and processes the externally input external control signal, as well as the voltage feedback (such as bootstrapping) from other components 800. Other components 800, together with the isolated drive chip, form a complete drive circuit on the PCB substrate. The processing chip modulates the switching signal into an AC signal and sends it to the drive output chip U2 through the isolation capacitor CG. The drive output chip U2 demodulates the AC signal into a switching signal and, after passing the internal control signal through circuit structures such as undervoltage protection, transmits it to the power device chip (equipped with a power device Q1) through a negative voltage drive circuit composed of other components, thereby controlling the switching state of the power device chip. The power device chip, through the change in the switching state, ultimately outputs power to the outside, i.e., realizes the high-voltage current drive function.

[0126] See Figure 4 The driving principle of the intelligent power module will be explained below:

[0127] The power supply VDD supplies power to the isolation driver chip, and the third capacitor C3 and the fourth capacitor C4 provide filtering for the power supply to the isolation driver chip. The third capacitor C3 and the fourth capacitor C4 can be integrated into the intelligent power module; or one of them can be placed in an external computer circuit, but this will reduce the filtering effect.

[0128] The input signals INPUT[0:3] represent external control signals sent from an external controller.

[0129] When the input signal INPUT[0:3] combination indicates that the power device Q1 is turned on, the isolation driver chip determines the output terminal corresponding to the power device Q1 that needs to be turned on, and outputs the internal control signal to the gate of the power device Q1 through the output terminal to realize the driving of the power device Q1; at the same time, the circuit driving function is optimized by bootstrapping, negative voltage driving, etc.

[0130] The specific packaging structure of the intelligent power module is described below:

[0131] See Figure 7 The packaging structure can be roughly divided into three parts:

[0132] 1. The input section, consisting of an isolated driver chip and a bootstrap circuit connected to an external controller; the driver circuit section, consisting of various surface-mount capacitors and resistors;

[0133] 2. The driving circuit section composed of various surface-mount capacitors and resistors;

[0134] 3. The output section consists of power device chips and their output circuits.

[0135] The input section forms the electrical isolation structure of the intelligent power module. The isolation driver chip is soldered onto the PCB board, and external control signals are input through the lead frame 500 above it. The power supply and bootstrap of the driver side in the isolation driver chip are also input from above. To ensure the isolation effect, a safe creepage distance is maintained between the power supply input and signal input pins. To ensure the integration and isolation requirements of the intelligent power module, a capacitor-isolated driver IC can be selected.

[0136] The driving circuit is bonded to the gate and source of the power device Q1. The gate serves as the driver, while the source provides a voltage reference for the negative voltage drive.

[0137] The final output section outputs the power signal through a half-bridge circuit composed of power device Q1. The thickness and quantity of the bonding wire 600 here need to be considered based on the actual application.

[0138] In this utility model, the terms "first", "second", "third", "fourth" and "fifth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0139] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0140] Although embodiments of the present invention have been shown and described above, the scope of protection of the present invention is not limited thereto. It is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, and substitutions to the above embodiments within the scope of the present invention, and such changes, modifications, and substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope of the claims.

Claims

1. A smart power module, characterized in that, The intelligent power module includes a first substrate, a second substrate, a capacitor-isolated driving circuit module, and a power circuit module; the capacitor-isolated driving circuit module is disposed on the first substrate, the power circuit module is disposed on the second substrate, and the first substrate and the power circuit module are electrically connected. in; The capacitor-isolated drive circuit module is used to receive external control signals, and after capacitively isolating the drive side receiving the external control signals from the power side where the power circuit module is located, it sends the internal control signal corresponding to the external control signal to the power circuit module.

2. The intelligent power module as described in claim 1, characterized in that, The first substrate is a printed circuit board, and the second substrate is a ceramic copper-clad laminate.

3. The intelligent power module as described in claim 1, characterized in that, The capacitor isolation drive circuit module includes an isolation unit and a signal output unit, and the power circuit module includes multiple power devices, with the signal output unit connected to each power device in a one-to-one correspondence; wherein: One set of output terminals of the isolation unit is connected to one of the signal output units.

4. The intelligent power module as described in claim 3, characterized in that, The isolation unit includes a processing chip and a capacitor subunit; the capacitor subunit includes multiple capacitor components, and the output terminal of the capacitor components serves as the output terminal of the isolation unit. The output terminals of the processing chip are connected one-to-one with the input terminals of the capacitor assembly; wherein: The processing chip is used to receive external control signals, convert the external control signals into alternating current and output them to the capacitor assembly, so that the capacitor assembly outputs the corresponding internal control signals.

5. The intelligent power module as described in claim 4, characterized in that, The capacitor assembly includes an isolation capacitor and a drive output chip; wherein: The first terminal of the isolation capacitor is connected to a set of output terminals of the processing chip, and the second terminal of the isolation capacitor is connected to the input terminal of the drive output chip, wherein the output terminal of the drive output chip serves as the output terminal of the capacitor assembly; wherein: The drive output chip is used to convert the signal received through the isolation capacitor into DC power to obtain the internal control signal, and send the internal control signal to the corresponding power device.

6. The intelligent power module as described in claim 5, characterized in that, The isolation capacitor includes a first metal electrode, a second metal electrode, a third metal electrode, and a fourth metal electrode; an insulating material is filled between the first metal electrode and the second metal electrode, and an insulating material is filled between the third metal electrode and the fourth metal electrode; wherein: The first metal electrode is connected to the output terminal of the processing chip, the second metal electrode is electrically connected to the third metal electrode, and the fourth metal electrode is connected to the input terminal of the drive output chip.

7. The intelligent power module as described in claim 5, characterized in that, A modulator is provided within the processing chip, and a demodulator is provided within the drive output chip; wherein: The processing chip is used to convert the external control signal into alternating current, and modulate the alternating current to a preset frequency through the modulator before outputting it to the capacitor assembly, so that the capacitor assembly outputs the corresponding internal control signal. The drive output chip is used to demodulate the internal control signal through the demodulator and convert the demodulated signal into DC power.

8. The intelligent power module as described in claim 3, characterized in that, The isolation unit includes an upper transistor output terminal, which includes a high-voltage terminal and a ground terminal; the signal output unit includes a negative voltage drive subunit, which includes a first capacitor, a second capacitor, a first Zener diode, and a third resistor; wherein: The positive terminal of the Zener diode is connected to the ground terminal of the isolation unit, the negative terminal of the Zener diode is connected to the source terminal of the power device, the negative terminal of the Zener diode is also connected to the first terminal of the third resistor, the second terminal of the third resistor is connected to the high-voltage terminal of the isolation unit, the first capacitor is connected in parallel with the third resistor, and the second capacitor is connected in parallel with the Zener diode.

9. The intelligent power module as described in claim 3, characterized in that, The isolation unit includes an upper transistor output terminal, which includes a high-voltage terminal and a ground terminal for the upper transistor; the capacitor isolation drive circuit module further includes a bootstrap unit, which includes a fourth resistor, a second diode, and a third capacitor; wherein: The first end of the fourth resistor is connected to the driving power supply, the second end of the fourth resistor is connected to the positive terminal of the second diode, the negative terminal of the second diode is connected to the high voltage terminal of the upper tube of the isolation unit, the first end of the third capacitor is connected to the high voltage terminal of the upper tube of the isolation unit, and the second end of the third capacitor is connected to the ground terminal of the upper tube of the isolation unit.

10. The intelligent power module as described in claim 1, characterized in that, The intelligent power module further includes a lead frame; wherein: The lead frame is electrically connected to the first substrate, the second substrate, and the power circuit module, respectively, and is used to lead out the electrodes on the first substrate, the second substrate, and the power circuit module to the corresponding pins.

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