An integrated chip structure

Abstract

This utility model relates to the field of integrated circuit packaging technology, specifically to an integrated chip structure. The integrated chip structure includes a main control chip, a switching transistor, a gallium nitride (GaN) power chip, a lead frame, and a molding compound. The switching transistor is electrically connected to both the main control chip and the GaN power chip. The main control chip outputs a PWM signal and drives the switching transistor to generate a negative voltage. This negative voltage drives the GaN power chip to turn on and off. The lead frame includes three electrically isolated base islands: a first base island, a second base island, and a third base island. The main control chip is disposed on the first base island, the switching transistor on the second base island, and the GaN power chip on the third base island. The first, second, and third base islands are encapsulated within the molding compound, with at least a portion of the side of the third base island facing away from the GaN power chip exposed outside the molding compound. This application can improve heat dissipation and extend the overall lifespan of the integrated chip structure.

Description

Technical Field

[0001] This utility model relates to the field of integrated circuit packaging technology, and in particular to an integrated chip structure. Background Technology

[0002] In some chargers, gallium nitride power devices, main control chips, and switching transistors are used in combination to achieve power and frequency regulation.

[0003] In existing circuit designs, gallium nitride (GaN) power devices, main control chips, and switching transistors are integrated into a single chip structure, simplifying the charger's circuitry. However, because GaN power devices generate a significant amount of heat during operation, integrating them into a single chip structure results in poor heat dissipation for the GaN power devices, leading to a reduced lifespan for the integrated chip structure. Utility Model Content

[0004] The technical problem to be solved by this utility model embodiment is to provide an integrated chip structure to solve the problem that the heat dissipation effect of the integrated chip structure on gallium nitride power devices is not good in the prior art, which leads to a decrease in the service life of the integrated chip structure.

[0005] This utility model discloses an integrated chip structure, including a main control chip, a switching transistor, a gallium nitride (GaN) power chip, a lead frame, and a plastic package. The switching transistor is electrically connected to the main control chip and the GaN power chip respectively. The main control chip is used to output a PWM signal and drive the switching transistor to generate a negative voltage through the PWM signal. The negative voltage is used to drive the GaN power chip to turn on and off. The lead frame includes a first base island, a second base island, and a third base island that are electrically isolated from each other. The main control chip is disposed on the first base island, the switching transistor is disposed on the second base island, and the GaN power chip is disposed on the third base island. The first base island, the second base island, and the third base island are encapsulated in the plastic package, and at least part of the side of the third base island facing away from the GaN power chip is exposed outside the plastic package.

[0006] Optionally, the lead frame further includes a first current detection pin, a second current detection pin, a third current detection pin, and a fourth current detection pin, all exposed on the molding compound. The first and second current detection pins are integrally formed with the third base island, the third current detection pin is separate from the third base island but electrically connected, and the portion of the third base island exposed on the molding compound forms the fourth current detection pin.

[0007] Optionally, the bottom edge of the main control chip forms a first angle with the horizontal direction, and the angle range of the first angle is 155°-165°.

[0008] Optionally, the bottom edge of the gallium nitride power chip forms a second angle with the horizontal direction, and the angle of the second angle is in the range of 20°-30°.

[0009] Optionally, the area of ​​the third base island is larger than the areas of the first base island and the second base island, and the first base island and the second base island are arranged on the same side of the third base island, with the first base island located below the second base island.

[0010] Optionally, the lead frame further includes a drain pin exposed on the molding compound, and the integrated chip structure further includes multiple first metal leads, with the drain of the gallium nitride power chip electrically connected to the drain pin through the multiple first metal leads.

[0011] Optionally, the integrated chip structure further includes a second metal lead, and the lead frame further includes a reference ground pin exposed on the molding compound. The reference ground pin is integrally formed with the first base island, and the ground terminal of the main control chip is electrically connected to the first base island through the second metal lead.

[0012] Optionally, the lead frame further includes a voltage feedback pin and a power input pin, and the integrated chip structure further includes a third metal lead and a fourth metal lead. The voltage feedback pin is electrically connected to the main control chip through the third metal lead, and the power input pin is electrically connected to the main control chip through the fourth metal lead.

[0013] Optionally, in the width direction of the molding compound, the lead frame has a first side and a second side opposite to each other, the first current sensing pin, the second current sensing pin and the drain pin are arranged on the first side, the reference ground pin, the power input pin, the voltage feedback pin and the third current sensing pin are arranged on the second side, and the first base island, the second base island and the third base island are located in the region between the first side and the second side.

[0014] Optionally, the main control chip is mounted on the first base island using insulating adhesive, the switching transistor is mounted on the second base island using first conductive adhesive, and the gallium nitride power chip is mounted on the third base island using second conductive adhesive.

[0015] Compared with the prior art, the beneficial effects of the integrated chip structure provided by the embodiments of this utility model are as follows: The integrated chip structure of this application embodiment is provided with a main control chip, a switching transistor, a gallium nitride power chip, a lead frame, and a plastic package. The lead frame is provided with a first base island, a second base island, and a third base island that are electrically isolated from each other. The main control chip is located on the first base island, the switching transistor is located on the second base island, and the gallium nitride power chip is located on the third base island. The first base island, the second base island, and the third base island are encapsulated in the plastic package, which provides support and heat conduction for the main control chip, the switching transistor, and the gallium nitride power chip, respectively. Moreover, the design of mutual electrical isolation can isolate the electrical interference of devices on different base islands. At least part of the side of the third base island facing away from the gallium nitride power chip is exposed to the plastic package, which can directly dissipate the heat generated by the gallium nitride power chip, improve the heat dissipation effect, and extend the overall service life of the integrated chip structure. Attached Figure Description

[0016] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0017] Figure 1 This is a schematic diagram of the internal bonding wires of the integrated chip structure provided in this embodiment of the utility model;

[0018] Figure 2 This is a schematic diagram of the planar structure of the integrated chip structure provided in this embodiment of the utility model.

[0019] The labels for the attached figures are as follows:

[0020] 110. Main control chip; 120. Switching transistor; 130. Gallium nitride power chip; 140. Lead frame; 140a. First base island; 140b. Second base island; 140c. Third base island; 140d. First current detection pin; 140e. Second current detection pin; 140f. Third current detection pin; 140g. Fourth current detection pin; 140h. Drain pin; 140i. Reference ground pin; 140j. Voltage feedback pin; 140k. Power input pin; 150. Molded package; 160. First metal lead; 170. Second metal lead; 180. Third metal lead; 190. Fourth metal lead. Detailed Implementation

[0021] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The preferred embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0022] This utility model embodiment provides an integrated chip structure, such as Figure 1 and Figure 2The integrated chip structure includes a main control chip 110, a switching transistor 120, a gallium nitride power chip 130, a lead frame 140, and a molding compound 150. The switching transistor 120 is electrically connected to both the main control chip 110 and the gallium nitride power chip 130. The main control chip 110 outputs a PWM signal and drives the switching transistor 120 to generate a negative voltage. This negative voltage is used to drive the gallium nitride power chip 130 to turn on and off. The lead frame 140 includes a first lead frame that is electrically isolated from the first lead frame. The three base islands are 140a, 140b, and 140c. The main control chip 110 is disposed on the first base island 140a, the switching transistor 120 is disposed on the second base island 140b, and the gallium nitride power chip 130 is disposed on the third base island 140c. The first base island 140a, the second base island 140b, and the third base island 140c are packaged in a plastic package 150, and at least part of the side of the third base island 140c facing away from the gallium nitride power chip 130 is exposed outside the plastic package 150.

[0023] The integrated chip structure of this embodiment includes a main control chip 110, a switching transistor 120, a gallium nitride power chip 130, a lead frame 140, and a molding compound 150. The lead frame 140 comprises electrically isolated first base islands 140a, second base islands 140b, and third base islands 140c. The main control chip 110 is disposed on the first base island 140a, the switching transistor 120 on the second base island 140b, and the gallium nitride power chip 130 on the third base island 140c. The 140c package is encapsulated in a plastic package 150, providing support and heat conduction for the main control chip 110, the switching transistor 120, and the gallium nitride power chip 130. The electrical isolation design can isolate electrical interference between devices on different base islands. At least part of the side of the third base island 140c facing away from the gallium nitride power chip 130 is exposed outside the plastic package 150, which can directly dissipate the heat generated by the gallium nitride power chip 130, improve heat dissipation, prevent the gallium nitride power chip 130 from overheating and being damaged, and extend the overall service life of the integrated chip structure.

[0024] Alternatively, the switching transistor 120 can be a MOSFET, which has a fast switching speed and can complete the switching between the on and off states in a very short time.

[0025] In an optional embodiment of this application, reference is made to Figure 1 and Figure 2The lead frame 140 also includes a first current detection pin 140d, a second current detection pin 140e, a third current detection pin 140f, and a fourth current detection pin 140g, all of which are exposed on the molding compound 150. The first current detection pin 140d and the second current detection pin 140e are integrally formed with the third base island 140c. The third current detection pin 140f is separated from the third base island 140c but electrically connected. The portion of the third base island 140c exposed on the molding compound 150 forms the fourth current detection pin 140g.

[0026] The first current detection pin 140d, the second current detection pin 140e, the third current detection pin 140f, and the fourth current detection pin 140g, exposed in the molding compound 150, can be soldered onto a circuit board for easy electrical connection with other components in the circuit. By configuring the first current detection pin 140d, the second current detection pin 140e, the third current detection pin 140f, and the fourth current detection pin 140g, users can flexibly configure them according to specific application requirements. For example, some or all of the pins can be used depending on the application scenario. Since the gallium nitride power chip 130 needs to monitor the current in the external circuit to ensure normal circuit operation, setting multiple current detection pins, and using the portion of the third base island 140c exposed in the molding compound 150 as the fourth current detection pin 140g, provides greater redundancy in the integrated chip structure. Even if some current detection pins fail, the normal current monitoring function of the gallium nitride chip can be guaranteed. Furthermore, this integrated chip structure is often used in fast charging circuits, where the detected current is often quite large. Multiple current detection pins can distribute the heat generated by the large current, further improving heat dissipation efficiency. Specifically, the first current detection pin 140d and the second current detection pin 140e are both integrally formed with the third base island 140c, which reduces the connection lines in the integrated chip structure, lowers circuit complexity, and reduces the connection resistance between the current detection pins and the third base island 140c, improving the accuracy and stability of signal transmission, and enhancing the reliability and stability of the circuit.

[0027] In an optional embodiment of this application, reference is made to Figure 1 The bottom edge of the main control chip 110 forms a first angle α with the horizontal direction, and the angle range of the first angle α is 155°-165°.

[0028] By rotating the main control chip 110 to form a first angle α of 155°-165° with the horizontal direction, the wiring path connecting the main control chip 110 to other chips and pins within the integrated chip structure can be shortened. This reduces resistance and loss, decreases crosstalk and electromagnetic interference between signals, and improves the anti-interference capability of the integrated chip structure. The shorter wiring path also makes the internal wiring of the integrated chip structure simpler and clearer, meaning less wiring material and cost, thereby reducing the cost of the integrated chip. Specifically, the first angle α can be any angle between 155° and 165°, such as 155°, 157°, 159°, 160°, 161°, 163°, or 165°. Preferably, the first angle α is 160°.

[0029] Further, refer to Figure 1 The bottom edge of the gallium nitride power chip 130 forms a second included angle β with the horizontal direction, and the angle range of the second included angle β is 20°-30°.

[0030] By rotating the gallium nitride power chip 130 so that its bottom edge forms a second included angle β of 20°-30° with the horizontal direction, the wiring path connecting the gallium nitride power chip 130 to other chips and pins within the integrated chip structure can be shortened. This reduces resistance and loss, decreases crosstalk and electromagnetic interference between signals, and improves the anti-interference capability of the integrated chip structure. The shorter wiring path also makes the internal wiring of the integrated chip structure simpler and clearer, meaning less wiring material and cost, thereby reducing the cost of the integrated chip. Specifically, the second included angle β can be any angle between 20° and 30°, such as 20°, 22°, 24°, 25°, 26°, 28°, or 30°. Preferably, the second included angle β is 25°.

[0031] In an optional embodiment of this application, reference is made to Figure 1 The area of ​​the third base island 140c is larger than the area of ​​the first base island 140a and the second base island 140b, and the first base island 140a and the second base island 140b are arranged on the same side of the third base island 140c, with the first base island 140a located below the second base island 140b.

[0032] Gallium nitride (GaN) power chips 130 typically generate significant heat during operation. By designing the area and location of the first base island 140a, second base island 140b, and third base island 140c, and optimizing the limited internal space of the lead frame 140 and the integrated chip structure, a larger area is allocated to the third base island 140c, where the heat-generating GaN chip resides. This helps to conduct heat more effectively to the lead frame 140 and the molding compound 150, improving heat dissipation efficiency, reducing the operating temperature of the GaN power chip 130, thereby extending its lifespan and improving reliability. Furthermore, placing the first base island 140a and second base island 140b on the same side of the third base island 140c, with the first base island 140a located below the second base island 140b, optimizes wiring and connections. This layout reduces wiring complexity and lowers wiring resistance and inductance.

[0033] Further, refer to Figure 1 and Figure 2 The lead frame 140 also includes a drain pin 140h exposed in the molding compound 150. The integrated chip structure also includes multiple first metal leads 160. The drain of the gallium nitride power chip 130 is electrically connected to the drain pin 140h through the multiple first metal leads 160.

[0034] The drain pin 140h exposed in the molding compound 150 can be soldered onto a circuit board for easy electrical connection with other components. By connecting the drain pin 140h to the drain of the gallium nitride power chip 130 via multiple first metal leads 160, the current can be distributed, with each first metal lead 160 carrying a portion of the current, thereby improving the overall current carrying capacity. This design can support higher operating currents, meeting the needs of high-power applications, while reducing the risk of overheating and damage to the first metal leads 160 due to excessive current.

[0035] It should be noted that the drain pin 140h can be defined as the D (drain) pin, or other symbolic names, without any restrictions.

[0036] Further, refer to Figure 1 and Figure 2 The integrated chip structure also includes a second metal lead 170, and the lead frame 140 also includes a reference ground pin 140i exposed in the molding compound 150. The reference ground pin 140i is integrally formed with the first base island 140a, and the ground terminal of the main control chip 110 is electrically connected to the first base island 140a through the second metal lead 170.

[0037] The reference ground pin 140i, exposed on the molding compound 150, can be soldered onto a circuit board for easy electrical connection to other components. The ground terminal of the main control chip 110 is directly connected to the first base island 140a via a second metal lead 170. Since the reference ground pin 140i and the first base island 140a are integrally formed, the resistance of the ground path is reduced, improving ground stability and thus enhancing the overall electrical performance of the chip. Furthermore, the integral formation of the reference ground pin 140i with the first base island 140a reduces soldering and connection steps during packaging, simplifying the packaging process and reducing complexity and cost.

[0038] It should be noted that the reference ground pin 140i can be defined as the GND pin or other symbol names, and there are no restrictions here.

[0039] Further, refer to Figure 1 and Figure 2 The lead frame 140 also includes a voltage feedback pin 140j and a power input pin 140k. The integrated chip structure also includes a third metal lead 180 and a fourth metal lead 190. The voltage feedback pin 140j is electrically connected to the main control chip 110 through the third metal lead 180, and the power input pin 140k is electrically connected to the main control chip 110 through the fourth metal lead 190.

[0040] The voltage feedback pin 140j and power input pin 140k, exposed in the molding compound 150, can be soldered onto a circuit board for easy electrical connection with other components. The voltage feedback pin 140j is connected to the main control chip 110 via a third metal lead 180, enabling the main control chip 110 to monitor changes in the output voltage in real time. This feedback mechanism is a key part of closed-loop control; the main control chip 110 can adjust the duty cycle of the PWM signal based on the feedback signal to precisely control the output voltage. The power input pin 140k is connected to the main control chip 110 via a fourth metal lead 190, providing a stable power input to the main control chip 110 and ensuring its normal operation.

[0041] It should be noted that the voltage feedback pin 140j can be defined as the FB (FeedBack) pin or other symbol names, without restriction. The power input pin 140k can be defined as the VCC pin or other symbol names, without restriction.

[0042] In an optional embodiment of this application, reference is made to Figure 1 and Figure 2In the width direction of the molding compound 150, the lead frame 140 has a first side and a second side. A first current detection pin 140d, a second current detection pin 140e, and a drain pin 140h are arranged on the first side. A reference ground pin 140i, a power input pin 140k, a voltage feedback pin 140j, and a third current detection pin are arranged on the second side. A first base island 140a, a second base island 140b, and a third base island 140c are located in the area between the first side and the second side.

[0043] Placing the current sensing pins (first current sensing pin 140d and second current sensing pin 140e) and drain pin 140h on the first side, and the reference ground pin 140i, power input pin 140k, voltage feedback pin 140j, and third current sensing pin 140f on the second side, effectively reduces electrical interference between different functional pins. For example, drain pin 140h typically carries a large current and may generate electromagnetic interference; placing it on the first side and high-precision signal pins (such as voltage feedback pin 140j) on the second side reduces interference with these high-precision signal pins and also makes the overall layout clearer. The first base island 140a, second base island 140b, and third base island 140c, located between the first and second sides, can be easily electrically connected to their corresponding pins, optimizing the wiring path and reducing wiring complexity and length.

[0044] In an optional embodiment of this application, the main control chip 110 is mounted on the first base island 140a with insulating adhesive, the switching transistor 120 is mounted on the second base island 140b with first conductive adhesive, and the gallium nitride power chip 130 is mounted on the third base island 140c with second conductive adhesive.

[0045] The main control chip 110 is mounted with insulating adhesive, which ensures good electrical isolation between the main control chip 110 and the first base island 140a, preventing leakage and short circuits. The switching transistor 120 and the gallium nitride power chip 130 are mounted on their respective base islands with conductive adhesive. The pins required by the switching transistor 120 and the gallium nitride power chip 130 are electrically connected to their respective base islands, reducing contact resistance. Furthermore, the conductive adhesive typically has good thermal conductivity, which can more effectively conduct the heat generated by the chip to the base island and the molding compound 150, improving heat dissipation efficiency, reducing the chip's operating temperature, thereby extending the chip's lifespan and improving reliability.

[0046] It should be understood that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; and all such modifications and substitutions should fall within the protection scope of the appended claims of this utility model.

Claims

1. An integrated chip structure, characterized in that, The device includes a main control chip, a switching transistor, a gallium nitride (GaN) power chip, a lead frame, and a plastic package. The switching transistor is electrically connected to both the main control chip and the GaN power chip. The main control chip outputs a PWM signal and drives the switching transistor to generate a negative voltage. This negative voltage drives the GaN power chip to turn on and off. The lead frame includes three electrically isolated base islands: a first base island, a second base island, and a third base island. The main control chip is disposed on the first base island, the switching transistor is disposed on the second base island, and the GaN power chip is disposed on the third base island. The first, second, and third base islands are encapsulated within the plastic package, with at least a portion of the side of the third base island facing away from the GaN power chip exposed outside the plastic package.

2. The integrated chip structure according to claim 1, characterized in that, The lead frame also includes a first current detection pin, a second current detection pin, a third current detection pin, and a fourth current detection pin, all of which are exposed on the molding compound. The first and second current detection pins are integrally formed with the third base island. The third current detection pin is separate from the third base island but electrically connected. The portion of the third base island exposed on the molding compound forms the fourth current detection pin.

3. The integrated chip structure according to claim 1, characterized in that, The bottom edge of the main control chip forms a first angle with the horizontal direction, and the angle range of the first angle is 155°-165°.

4. The integrated chip structure according to claim 3, characterized in that, The bottom edge of the gallium nitride power chip forms a second angle with the horizontal direction, and the angle range of the second angle is 20°-30°.

5. The integrated chip structure according to claim 1, characterized in that, The area of ​​the third base island is larger than the areas of the first base island and the second base island, and the first base island and the second base island are arranged on the same side of the third base island, with the first base island located below the second base island.

6. The integrated chip structure according to claim 2, characterized in that, The lead frame also includes a drain pin exposed on the molding compound, and the integrated chip structure also includes multiple first metal leads. The drain of the gallium nitride power chip is electrically connected to the drain pin through the multiple first metal leads.

7. The integrated chip structure according to claim 6, characterized in that, The integrated chip structure further includes a second metal lead, and the lead frame further includes a reference ground pin exposed on the molding compound. The reference ground pin is integrally formed with the first base island, and the ground terminal of the main control chip is electrically connected to the first base island through the second metal lead.

8. The integrated chip structure according to claim 7, characterized in that, The lead frame also includes a voltage feedback pin and a power input pin. The integrated chip structure also includes a third metal lead and a fourth metal lead. The voltage feedback pin is electrically connected to the main control chip through the third metal lead, and the power input pin is electrically connected to the main control chip through the fourth metal lead.

9. The integrated chip structure according to claim 8, characterized in that, In the width direction of the molding compound, the lead frame has a first side and a second side opposite to each other. The first current sensing pin, the second current sensing pin and the drain pin are arranged on the first side, and the reference ground pin, the power input pin, the voltage feedback pin and the third current sensing pin are arranged on the second side. The first base island, the second base island and the third base island are located in the region between the first side and the second side.

10. The integrated chip structure according to claim 1, characterized in that, The main control chip is mounted on the first base island using insulating adhesive, the switching transistor is mounted on the second base island using first conductive adhesive, and the gallium nitride power chip is mounted on the third base island using second conductive adhesive.

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