HybridPACK(TM) Drive Power Module with SiC- MOSFET’s and Monolithic RC- Snubber Chips for Optimized Power Density

Abstract:
The snappiness of the parasitic body diodes of SiC- MOSFETs lead to high voltage overshoots, often exceeding the physical limits of the chip technology. The impact of monolithic RC-snubber chips paralleled to MOSFET half bridges were investigated in HybridPACK(TM) Drive power modules. Due to the filter-effect no oscillation effects occur and the EMI-amplitude is reduced by 30 dB. For diode recovery operation a significant overvoltage reduction is found. Hence, lower (RG,on)-resistors can be used which results in lower total dynamic losses (26%).This saving-effect is significant and manifests itself in 8% higher RMS-currents or in 12% lower junction temperatures.