Research On Silicon-based GaN Monolithic Integrated Power IC

With the development of automotive electronics and data centers power electronic market,high efficiency,high power density,high reliability,high speed and light weight have become the main development trends of power integrated circuits.The superior performance of GaN power semiconductors in high frequency,high efficiency,high temperature operation and the resulting high power density characteristics are the competitive advantages of GaN compared with mainstream Si-based power semiconductors and emerging power semiconductors such as Si C and Ga O.Maximizing the high-efficiency,high-speed performance advantages of GaN power devices is the key to GaN's wider application and competitive advantage.As for the GaN application,compared with the traditional GaN discrete device application scheme,GaN monolithic power IC technology greatly reduces the parasitic effects caused by multi-chip interconnection by integrating GaN power devices,driving ? protection circuits,and control circuits on the same chip.GaN monolithic power IC technology is an ideal technical solution for GaN power semiconductors to maximize their performance.At present,the core problems of GaN monolithic integrated driving technology mainly lie in the transient and steady-state driving capability,the design of driving control circuits,and the protection capabilities for abnormal states of GaN power devices.Based on the p-GaN gate E-mode GaN monolithic integration platform,this thesis demonstrates a high driving capability and high reliability GaN-based gate driver circuit.The proposed gate driver mainly includes:(1)Driving stage circuit with dead-time control function,with high current driving capability of 1.2A source current and 3.35 A sink current,its 5ns transmission delay can ensure the high frequency switching characteristics of GaN power devices.(2)PWM circuit,which can realize the flexible regulation of the frequency and duty cycle,or formulate the drive strategy as a controller.In addition,the on-chip integrated PWM module will eliminate the need for off-chip PWM chip and reduce the driver design costs(3)The overcurrent protection circuit proposed based on the Sense HEMT realizes a 10 ns overcurrent response time,and has functions such as blanking time generation and protection mode selection.(4)The over-temperature protection circuit proposed based on the temperature resistance integrated inside the GaN power device realizes the over-temperature protection triggered by 150°C,with a hysteresis window of25°C.(5)The under-voltage lockout circuit can provide a voltage unlocking point of4.75 V,the hysteresis window is 0.3V,ensures the normal working voltage of each module in the gate driver.The above-mentioned circuits are simulated and verified based on the established high-precision ASM-HEMT GaN Spice model.The simulation results show that the design of each circuit meets the driving requirements of GaN power devices.