Research And Design Of Monolithic Fully Integrated GaN Driver Chip

GaN power devices have the advantages of higher electron mobility,lower on-resistance and smaller parasitic capacitance than traditional silicon（Si）material devices.Therefore,they are often used for higher output power and higher efficiency and higher power density power supply systems.In power system applications,GaN power devices must be effectively controlled by drive circuits,but traditional discrete drive solutions（hybrid drive solutions using silicon-based gate drivers to driver GaN power transistors）are often affected by the parasitic inductance of PCB wiring.so the problem of gate ringing is easy to occur when working at high frequencies,which challenges the reliability of the driver chip.Therefore,it is of great research significance to design a monolithic fully integrated GaN driver chip with low power consumption and high reliability.Firstly,the conduction principle and gate breakdown characteristics of GaN devices are analyzed in this thesis,which provides a theoretical basis for the reliability design of driving circuits.Then,the problems of large static power consumption、insufficient gate voltage of output stage and excessive d V/dt in the design of GaN driver circuit are studied in this thesis.In order to solve the above problems,this thesis designs a low-power logic circuit to solve the static power consumption problem caused by the lack of p-transistor GaN process;an output stage circuit with slope control and voltage bootstrap is designed to solve the problem of insufficient gate voltage and the problem of excessive d V/dt;an integrated voltage regulation circuit is designed to supply power to the input stage and the driver stage,which solves the problem of power consumption caused by external clamping diodes,improves system integration and reduces power consumption.Finally,according to the requirements of the index,the design of a monolithic fully integrated GaN driver circuit with low power consumption and high reliability is completed.The monolithic fully integrated GaN driver chip designed in this thesis is tape-out and tested based on the GaN-on-Si process.The test results show that under the working conditions of V_BUS=200V,V_CC=15V,and fsw=2MHz,the logic function of the chip is normal,the quiescent current is less than 1.5m A,and the transmission delay is less than 20ns,which meets the design requirements.