Ultrafast Gate Driver With GaN HEMTs for ns-Pulse Generator Using SiC MOSFET

Shorter voltage and current rise/fall time are the main driving forces for nanosecond pulse power technology. The switching capabilities of SiC-MOSFET directly determine the dynamic characteristics of most solid-state pulse topologies. The core to explore the dynamic performance potential of SiC-MOSFET is the ultrafast gate driver with a high instantaneous current. It also is the guarantee for generating nanosecond pulses with shorter rising time. In this article, we discuss the influence of the driver’s parasitic parameters on the driving capacity and propose the GaN-based driver with extremely low turn-on parasitic inductance (< 1 nH) by the integrated structure of multi-layer printed circuit board (PCB) wiring. We compared the proposed driver with the RF-Si-based high-speed and high-current gate driver of the commercial low inductance package. The results show that the driver using GaN HEMTs has unique dynamic advantages, and the
${U} _{\text {gs}}$
rise and fall time is 2.3 and 3.8 ns, respectively. The dynamic characteristics of SiC-MOSFET have been extremely optimized in the full-scale load test. The voltage turn-on speed is 215 kV/
$\mu \text{s}$
(2.4 times increased), and the turn-off speed is 206 kV/
$\mu \text{s}$
(2 times increased). The current rise speed is 8.3 kA/
$\mu \text{s}$
(2.2 times increased) and the fall speed is 6 kA/
$\mu \text{s}$
(1.4 times increased) with the limit pulse current.