Evaluation of SiC MOSFET Key Parameters for Nanosecond Pulsed Field Ablation: Investigating Discrepancies Between Experimental Data and Manufacturer Datasheet Values

Nanosecond pulsed field ablation (nsPFA) is a promising modality for clinical tissue ablation. The performance of the pulse generator (PG) strongly depends on the switching characteristics of the SiC MOSFET. Currently, many key parameters listed in SiC MOSFET datasheets are determined using double-pulse test circuits with inductive loads, whereas loads in nsPFA-applications are predominantly resistive. This study proposes a test scheme for SiC MOSFETs under nsPFA-like operating conditions. Key parameters to be evaluated are pulsed drain current (IDM), on-resistance (Ron), rise/fall time, turn-on/off delay, and minimum pulse width. The results show significant differences between manufacturer datasheet values and experimental data. For example, one switch under test has an Idm value of 40 A in the datasheet but 153 A in experimental test. This study recommends that custom testing of SiC MOSFETs is essential when designing PGs for nsPFA-applications.