An Isolated Gate-Drive Method for Series MOSFETs in a Wide Adjustable Pulsewidth Range

Solid-state switching semiconductors, such as
mosfet
s, can realize high repetitive high-voltage pulse output with a wide adjustable pulsewidth range, which are of interest in laser technology and application, X-ray tomography, ion implantation, etc. In this article, an isolated drive method was proposed to realize driving series
mosfet
s in a wide adjustable pulsewidth range in high repetitive high-voltage applications while omitting the need for isolated power supplies. In the drive method proposed, charging and discharging paths for the input capacitance of the main
mosfet
s are set, respectively, and narrow
on/off
isolated drive pulse signals are utilized. Its operation stages, expressions for the voltage and current in turn-
on
and turn-
off
transient, and design basis of an optimal dead time delay have been presented in a detailed analysis. Through applying the proposed series
mosfet
s drive method, a 130 ns–28 ms adjustable pulsewidth range, 3000 V, 10 kHz repetition rate, 24 ns rise time, and 34 ns fall time high-voltage pulse output was realized, and the continuous switching capability was verified. These results proved that the isolated drive method we proposed can achieve driving series
mosfet
s in a wide adjustable pulsewidth range and is practical in high-voltage and high repetition rate applications.