Silicon IC-GaN hybrid drive system

Abstract

The present invention discloses a silicon IC-gallium nitride hybrid drive system, including a drive module and a gallium nitride power device; the drive module includes a silicon IC linear buck component for outputting a preset voltage and a gallium nitride monolithic integrated drive half-bridge component; the output end of the gallium nitride monolithic integrated drive half-bridge component is connected to the gate circuit signal of the gallium nitride power device to modulate the conductivity of the gallium nitride power device by charging and discharging; the silicon IC linear buck component and the gallium nitride monolithic integrated drive half-bridge component are connected by wire bonding; the drive module and the gallium nitride power device are matched by a common packaging method. The present invention includes at least the following advantages: combining the advantages of silicon IC integrated circuits, flexibility, low cost, and maturity, and the benefits of gallium nitride monolithic integrated half-bridge components to eliminate parasitic parameters of the drive circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics and power semiconductors, and in particular to a silicon IC-gallium nitride hybrid drive system. Background Art

[0002] The description in this section merely provides background information related to the present disclosure and does not constitute prior art.

[0003] Gallium nitride is known as the representative material of the third-generation semiconductors. It has achieved large-scale mass production in the field of small and medium-power adapters and is expected to completely replace silicon in some fields in the near future. However, the application of gallium nitride power devices requires corresponding gate driver chips. Ordinary silicon power device driver chips cannot be directly applied to gallium nitride power devices because the requirements for performance such as driving voltage and driving capability are different.

[0004] At present, GaN power devices are mainly in the form of discrete components and integrated ICs with drivers. Discrete components have good design flexibility, but the parasitic parameters of the external drive circuit will inevitably cause the drive loop to oscillate, resulting in reduced conversion efficiency and even tube explosion. There are two ways to implement integrated ICs with drivers: the first is GaN monolithic integration, which uses GaN monolithic integrated drivers and power devices (such as Figure 1 ); Another way is to use a relatively mature silicon driver IC and a gallium nitride power device in a sealed package (such as Figure 2 ).

[0005] Existing monolithic integrated GaN ICs lack CMOS logic commonly used in silicon analog circuits (currently, GaN processes do not have p-type high electron mobility transistors (P-type HEMTs), and can only use depletion-mode HEMTs and enhancement-mode HEMTs in combination). This shortcoming results in limited functions of GaN monolithic integrated analog circuits, lacks some necessary functional units, and cannot implement some more complex protection and control circuits. At the same time, the price of GaN far exceeds that of silicon per unit chip area, and the current process node (minimum line width) of GaN is much larger than that of silicon, resulting in a high cost for GaN monolithic integration.

[0006] Although the existing co-packaging method takes advantage of the mature silicon-based analog circuits, the parasitic inductance is inevitable because the silicon IC chip and the gallium nitride chip need to be connected by wire bonding, even if the wire diameter is very short. Especially when the output pad of the silicon IC chip or the gate pad of the gallium nitride device is not large enough to bond thicker copper wires / gold wires, the parasitic inductance cannot be ignored.

[0007] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0008] In order to overcome the defects in the prior art, an embodiment of the present invention provides a silicon IC-gallium nitride hybrid drive system, which combines the advantages of silicon IC integrated circuits, flexibility, low cost, and maturity, and the benefits of gallium nitride monolithic integrated half-bridge components to eliminate parasitic parameters of the drive loop.

[0009] The embodiment of the present application discloses: a silicon IC-gallium nitride hybrid drive system, including a drive module and a gallium nitride power device;

[0010] The driving module includes a silicon IC type linear buck component and a gallium nitride monolithic integrated driving half-bridge component for outputting a preset voltage;

[0011] The output end of the GaN monolithic integrated driving half-bridge component is connected to the gate circuit signal of the GaN power device to modulate the conductivity of the GaN power device by charging and discharging;

[0012] The silicon IC type linear buck component and the gallium nitride monolithic integrated driving half-bridge component are connected by wire bonding;

[0013] The driving module and the gallium nitride power device are matched with each other in a co-packaging manner.

[0014] Furthermore, the length of the connection wire used for bonding between the silicon IC type linear buck component and the gallium nitride monolithic integrated driving half-bridge component is less than 2 mm.

[0015] Furthermore, the driving module also includes a silicon IC type undervoltage lockout component signal-connected to the gallium nitride monolithic integrated driving half-bridge component.

[0016] Furthermore, when the gate voltage of the gallium nitride power device is lower than its threshold voltage, the gallium nitride power device is in a disconnected state; wherein the threshold voltage is between 1V and 2V.

[0017] Furthermore, when the gate voltage of the gallium nitride power device is higher than its threshold voltage and reaches its preset working voltage, the gallium nitride power device is in the on state; wherein the preset voltage is between 5V and 7V.

[0018] Furthermore, the GaN integrated half-bridge component includes two semiconductor transistors in a half-bridge arrangement.

[0019] Furthermore, the substrate of the gallium nitride power device is made of silicon material.

[0020] Furthermore, the wafer size of the GaN integrated driver half-bridge and the GaN power device is 6 inches or 8 inches.

[0021] Furthermore, the silicon IC type linear buck component is integrated on one chip, and the gallium nitride power device and the gallium nitride monolithic integrated driving half-bridge component are integrated on another chip.

[0022] By means of the above technical scheme, the beneficial effects of the present invention are as follows: the hybrid drive combines the advantages of flexibility, low cost and maturity of silicon IC integrated circuits and the benefits of gallium nitride monolithic integrated half-bridge components to eliminate parasitic parameters of the driving circuit; the advantage of this is that the gallium nitride monolithic integration is used as the last-stage driving half-bridge to eliminate the parasitic parameters of the driving circuit between the driving module and the gallium nitride power device; and the wire bonding method is used to make the two chips co-sealed, and the silicon IC of the previous stage can greatly reduce the area and cost of the silicon IC because it does not have the last-stage driving half-bridge. At the same time, because the gallium nitride monolithic integration is used as the last-stage driving half-bridge, compared with the silicon process, the upper and lower tube areas required for the same driving capability are very small, which will not affect the total cost of the gallium nitride power device.

[0023] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the structure of a gallium nitride monolithic integrated drive and power device in the background technology of the present invention;

[0026] Figure 2 It is a schematic diagram of the structure of a silicon driver IC and a gallium nitride power device in the background technology of the present invention;

[0027] Figure 3 Schematic diagram of the structure of the silicon IC-gallium nitride hybrid drive system in an embodiment of the present invention.

[0028] The figure numbers of the above figures are: 1. Silicon IC type linear buck component; 2. GaN monolithic integrated driving half-bridge component; 3. GaN power device; 4. MOS tube; 5. Resistor; 6. Operational amplifier; 7. Upper tube; 8. Lower tube. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, and they cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0031] Combination Figure 3 As shown, in this embodiment, a silicon IC-gallium nitride hybrid drive system is disclosed, including a drive module located on the left and a gallium nitride power device 3 located on the right. The drive module includes a silicon IC linear buck component 1 for outputting a preset voltage, a plurality of drive protection function components, and a gallium nitride monolithic integrated drive half-bridge component 2. It is worth noting that the silicon IC linear buck component 1 is integrated on one chip, and the gallium nitride power device 3 and the gallium nitride monolithic integrated drive half-bridge component are integrated on another chip.

[0032] In this embodiment, the silicon IC type linear buck component 1 is composed of a MOS tube 4, an operational amplifier 6 and two series resistors 5; it should be noted that the system includes a plurality of other driving protection circuits that can cooperate with the silicon IC type linear buck component 1. Since the input voltage required for the normal operation of the silicon IC type linear buck component 1 is about 12V, and the working voltage required by the gate of the gallium nitride power device 3 is about 5-7V, in this embodiment, the working voltage there is 6V. Through the above-mentioned silicon IC type linear buck component 1 (LDO) setting, the higher input voltage can be adjusted to the voltage range that the gallium nitride power device 3 can use in a relatively stable manner.

[0033] The basic principle of the silicon IC linear buck component 1 is that the input and output voltages are dropped between the drain and source of the MOS tube 4. In order to stabilize the output voltage, the silicon IC linear buck component 1 also has a feedback detection function. Specifically, the two resistors 5 connected in series can realize the function of output voltage division; preferably, by adjusting the resistance value of the resistor 5, the ideal output voltage value and the voltage value corresponding to the bandgap reference can be obtained, and by comparing the difference between the two, the operational amplifier 6 is used to realize automatic adjustment, thereby achieving the purpose of stabilizing the output voltage.

[0034] In this embodiment, the GaN monolithic integrated driving half-bridge component 2 is implemented by GaN monolithic integration. Figure 2 The existing silicon IC driver replaces the last stage driving half bridge (composed of two N-LDMOS) of the silicon IC driver. On the one hand, it can eliminate the parasitic parameters generated by the driving circuit between the GaN monolithic integrated driving half bridge component 2 and the GaN power device 3. On the other hand, it can greatly reduce the area and cost of the chip where the silicon IC linear buck component 1 and multiple driving protection functional components are located. It is worth noting that the GaN monolithic integrated driving half bridge component 2 is relatively small compared to the silicon IC driving half bridge, under the same driving capability, and will not affect the area and total cost of the chip where the GaN monolithic integrated driving half bridge component 2 is located.

[0035] In the above embodiment, the GaN integrated half-bridge component includes two semiconductor transistors arranged in a half-bridge configuration, combined with Figure 3 As shown, the upper tube 7 is located at the top, and the lower tube 8 is located at the bottom.

[0036] In this embodiment, in the offline power supply application, the gallium nitride power device 3 is mainly used as a main switch in the system, and has advantages such as a good high breakdown electric field, lower on-resistance, and lower parasitic capacitance. The output end of the gallium nitride monolithic integrated driving half-bridge component 2 is connected to the gate circuit signal of the gallium nitride power device 3 to modulate the conductivity of the gallium nitride power device 3 by charging and discharging.

[0037] The above-mentioned implementation mode is specifically that when the gate voltage of the GaN power device 3 is zero, or lower than its threshold voltage (generally about 1.5V), the conductive channel from the drain to the source of the GaN power device 3 is in an open state, the resistance is very large, and it can withstand a high voltage exceeding 650V.

[0038] When the external control signal is high, the output terminal of the driving module is at a high potential, and the driving module charges the gate of the gallium nitride power device 3. Specifically, the current flows from the upper tube 7 of the gallium nitride monolithic integrated driving half-bridge component 2 to the gate of the gallium nitride power device 3, so that the gate voltage of the gallium nitride power device 3 exceeds the threshold voltage and reaches the gate voltage required for normal operation (usually about 6V), the gallium nitride power device 3 is turned on, and the resistance between the drain and the source becomes very small.

[0039] When the external control signal is low, the output end of the driving module is at a low potential, the lower tube 8 of the gallium nitride monolithic integrated driving half-bridge component 2 of the driving circuit is turned on, and the upper tube 7 is turned off, and the current quickly extracts charge from the gate of the gallium nitride power device 3, so that the gate voltage of the gallium nitride power device 3 decreases; when the gate voltage of the gallium nitride power device 3 decreases to below the threshold voltage, the gallium nitride power device 3 is turned off, and the drain to gate maintains a high impedance state, which can withstand high voltage.

[0040] In this embodiment, the driving module and the gallium nitride power device 3 are matched in a common packaging manner, that is, the driving module and the gallium nitride power device 3 are packaged together in a plastic package. At this time, the two chips of the hybrid drive system of the present application are connected by wire bonding. The length of the connecting wire used in the above-mentioned wire bonding is very short, usually less than 2mm, and the parasitic inductance generated is very small (~1nH), which greatly reduces the parasitic parameters caused by the routing and facilitates the system design.

[0041] The above configuration combines the advantages of flexibility, maturity and low cost of silicon IC drive circuits with the advantages of low parasitic parameters of GaN monolithic drive integration, where the latter is achieved by implementing the last stage of the drive module by GaN monolithic integration design.

[0042] In this embodiment, the driving module also includes a silicon IC undervoltage lockout component that is signal-connected to the gallium nitride monolithic integrated driving half-bridge component 2. The function of the silicon IC undervoltage lockout component is to shut down the corresponding chip to protect the system when the power supply voltage is lower than a certain voltage value. When the power supply voltage is higher than the preset voltage value, the work is restarted. The driving module also includes an active clamping component, the function of which is to protect the gate of the subsequent gallium nitride power device 3 from the influence of high voltage spikes; the reason is that the gate voltage range of the enhanced gallium nitride power device 3 is narrower than that of silicon or silicon carbide, and a gate voltage exceeding 8V will reduce the device life and even permanently damage the chip.

[0043] In this embodiment, the substrate of the gallium nitride power device 3 is made of silicon material, wherein preferably, the wafer size of the gallium nitride monolithic integrated driving half-bridge component and the gallium nitride power device 3 are both 6 inches or 8 inches.

[0044] Regarding the hybrid drive system of the present application, its application fields may include:

[0045] 1. Consumer power products, such as mobile phone fast charging, adapters, PC power supplies, white appliances, etc.;

[0046] 2. Industrial power supply, such as server power supply, communication power supply, etc.;

[0047] 3. Electric vehicle on-board charger, on-board DC-DC converter, etc.

[0048] In these application areas, the system efficiency can be improved and the system volume can be reduced. At the same time, the use of a hybrid drive system can further simplify the circuit board design and reduce parasitic parameters.

[0049] The present invention uses specific embodiments to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A silicon IC-gallium nitride hybrid drive system, It is characterized in that Including driver module and GaN power device; The driving module includes a silicon IC type linear buck component and a gallium nitride monolithic integrated driving half-bridge component for outputting a preset voltage; The output end of the GaN monolithic integrated driving half-bridge component is connected to the gate circuit signal of the GaN power device to modulate the conductivity of the GaN power device by charging and discharging; The silicon IC type linear buck component and the gallium nitride monolithic integrated driving half-bridge component are connected by wire bonding; The driving module and the gallium nitride power device are matched with each other by using a common packaging method; The driving module also includes a silicon IC undervoltage lockout component signal-connected to the gallium nitride monolithic integrated driving half-bridge component; the silicon IC undervoltage lockout component is used to shut down the corresponding chip to protect the system when the power supply voltage is lower than a certain voltage value; and restart the work when the power supply voltage is higher than a preset voltage value; the driving module also includes an active clamping component, and the active clamping component is used to protect the gate of the gallium nitride power device from the influence of high voltage spikes.

2. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that The length of the connection wire used for bonding between the silicon IC type linear buck component and the gallium nitride monolithic integrated driving half-bridge component is less than 2 mm.

3. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that When the gate voltage of the GaN power device is lower than its threshold voltage, the GaN power device is in a disconnected state; wherein the threshold voltage is between 1V and 2V.

4. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that When the gate voltage of the GaN power device is higher than its threshold voltage and reaches its preset working voltage, the GaN power device is in the on state; wherein the preset voltage is between 5V and 7V.

5. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that The gallium nitride integrated half-bridge component includes two gallium nitride semiconductor transistors arranged in a half-bridge.

6. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that The substrate of the gallium nitride power device is made of silicon material.

7. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that The wafer sizes of the GaN integrated driving half-bridge and the GaN power device are both 6 inches or 8 inches.

8. The silicon IC-gallium nitride hybrid drive system according to claim 1, It is characterized in that The silicon IC type linear buck component is integrated on one chip, and the gallium nitride power device and the gallium nitride monolithic integrated driving half-bridge component are integrated on another chip.

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