Modeling the switching behaviour of SuperJunction MOSFETs in cascode configuration with a low voltage silicon MOSFET

This work presents a piecewise model to predict electrical waveforms of SuperJunction Cascode Configurations (SJ-CCs) during hard-switching operation. This ultra-fast high-voltage switch is composed of a SuperJunction MOSFET (SJ-FET) in Cascode Configuration (CC) with a Low-Voltage silicon MOSFET (LV-FET). SJ-CCs have been recently proposed as the first solution fully-based on silicon technologies that outperforms standalone SJ-FETs in high-frequency power converters. The model deeply explains its switching behaviour and it takes into account the most relevant parasitic elements and the strong nonlinearity of the SJ-FET capacitances. Moreover, the model is validated with experimental measurements in a 240W boost converter using a SJ-CC composed of discrete devices.