Design Of The Drive Chip For SiC Switch Devices

SiC switch device is currently the focus of research in the field of power electronics, the SiC MOSFET, as the most typical power electronic switch device, is widely used in the power electronic circuits with high breakdown voltage, high current transmission capacity, low power loss, high working temperature. And SiC MOSFET drive circuit, as the interface between the high voltage circuit and low voltage control circuit, directly determines the switch device’s working condition. But the increase of switching frequency results in higher switching loss. Current drive circuit can’t solve the switching loss problem.This paper proposes a closed-loop control strategy of SiC MOSFET drive, and according to the strategy, we design and produce a SiC MOSFET drive chip. The major function of the chip is providing SiC MOSFET-5V~15V driving voltage and controllable current, and the external detection circuit provides di/dt and dv/dt signals to adjust positive and negative driving current values dynamically, so that the closed loop control of SiC switch device reduce its switch loss.The chip contains the level shift module, the comparator module, the logic control module and the current driving module. This article firstly shows the basic principles of each module, gradually discusses the circuit design principle and simulation results of the chip. Next, the layout design and post simulation results of the chip are introduced based on the design rules of the technology platform. Eventually, the tape-out chip’s test results shows that the driver chip can provide an effective voltage and controllable drive current to SiC MOSFET and the whole circuit’s delay is controlled in less than 10 ns, and the switching loss of the SiC switch devices reduce 35% ultimately.