Modelling GaN-HEMT Dynamic ON-state Resistance in High Frequency Power Converter

Abstract

In order to model GaN device dynamic RDSon value due to trapped charge, a measurement circuit to accurately measure device dynamic RDSon value under different OFF-state time and ON-state time is at first proposed. Based on measurement results, an analytical model with different cells is proposed to represent dynamic RDSon evolution. It is then represented as a behavioural voltage source to compensate device ON-state VDS voltage, which can be implemented easily into device manufacturer model in Spice-type electrical circuit simulator. The model is then validated by comparing with the measurement on device dynamic RDSon value of different switching frequencies, where the model agrees with experimental results on both transient and stabilized dynamic RDSon value.