Suppression of Switching Crosstalk and Voltage Oscillations in a SiC MOSFET Based Half-Bridge Converter

Abstract

The silicon carbide (SiC) MOSFET is characterized by high operating voltage, temperature, switching frequency and efficiency which enables a converter to achieve high power density. However, at high switching frequency, the crosstalk phenomenon occurs when the gate voltage spike introduced by high dv/dt and voltage ringing forces false turn-on of SiC MOSFET which causes a crow-bar current thereby increasing switching losses. In order to increase the immunity against the crosstalk phenomenon in a half-bridge configuration, this paper presents a gate driver for SiC MOSFET capable of generating the negative turn-off voltage without using a negative power supply. In addition, the effect of parasitic inductances on the switching response is analyzed and an RC snubber is designed using high-frequency based circuit reduction technique to dampen the switching ringing. The performance of the proposed gate driver and the designed RC snubber is validated using simulation and experiment at the 1 MHz switching frequency. The results show that the proposed gate driver with RC snubber eliminates crosstalk by maintaining any spurious gate spike below the gate threshold voltage.

Review of Packaging Schemes for Power Module

“…The undesired power losses are then generated in both high-and low-side MOSFETs, leading to an increase in their junction temperature and decrease in efficiency [69]. SiC MOSFET is more vulnerable to false triggering due to its low threshold voltage compared with Si counterpart [69], [70]. For instance, threshold voltage of IGBT 5SMY 12K1280 from ABB is 5-7 V [71], while for SiC MOSFET CPM2-1200-0025B from CREE, the value is only 2.6 V [72].…”

An Investigation of Gate Voltage Oscillation and its Suppression for SiC MOSFET

“…However, the fast switching characteristics of SiC MOSFET also poses challenges as their benefits are limited by the packaging technology, specifically the parasitic parameters [7][8][9][10]. Due to large dv/dt slew rate, the parasitic capacitance in the SiC MOSFET brings crosstalk and false turn-on issues, which have been discussed in previous studies [11][12][13][14]. On the other hand, the issues of gate voltage spikes and oscillations from the stray parameters remains under consideration [15,16].…”

Comparative Design of Gate Drivers with Short-Circuit Protection Scheme for SiC MOSFET and Si IGBT

“…It may lead to parasitic effects including phase-leg crosstalk and electromagnetic interference (EMI) issues due to the ringings, which are where the early works mainly focused on. To summarize, the gate driver design for SiC MOSFET should follow such rules [9][10][11][12]:…”