The Research And Implementation Of High-side Power Supply For GaN Driver ICs

The enhanced Gallium Nitride(GaN)power devices have been used in high-frequency and high-power density systems due to their high operating frequency,low switching loss and high critical breakdown voltage.In the bridge drive system,the high-side power supply technology that supplies power to the high-side circuit is one of the key technologies of the GaN driver ICs.When the traditional high-side power supply circuit is applied in the GaN power device drive system,there is inevitably a problem that it is difficult to compromise between power consumption and reliability.Therefore,it is of great significance to systematically study the power consumption and reliability of high-side power supply circuits.Firstly,this thesis describes the high-side power power supply mechanism of GaN driver chip based on GaN bridge driver system.The several traditional high-side power supply technologies of GaN driver ICs have been researched,which indicate that the contradiction between reducing power consumption and improving chip VS negative bias capability.Therefore,a low-power and high-reliability high-side power supply circuit is proposed in this thesis,which consists of an active clamp circuit and a VS negative bias boost circuit.In the active clamp circuit,the high-side power supply circuit is controlled to turn off by detecting that the VS voltage is negative,and realizes the low-power output stage clamp function of the GaN drive chip.In the VS negative bias boost circuit,the dual-channel integrated bootstrap power supply technology is utilized to supply high-side circuit,the problem of the drive signal transmission interruption under the VS is negative voltage can be solved and the VS negative bias capability of GaN driver ICs is improved effectively.The high-side power supply circuit designed in this thesis is based on 600 V Bipolar-CMOS-DMOS(BCD)process for simulation and tapeout.The test results of tapeout wafer show that,the maximum of high-side quiescent current is 66.7?A when VS is-6V,the allowable negative swings to-6.2V and GaN driver ICs have clamping protection capability under the condition of 600 V power voltage,5V power supply voltage and 1.25 MHz signal transmission frequency.