In this paper, the influence of traps on the dynamic on-resistance (R dson ) and switching time of AlGaN/GaN high-electron-mobility transistors is validated by means of a switching power converter with floating buck-boost topology. A new scheme based on the voltage-dependent dynamic R dson is proposed to extract the average activation energy of device degradation. The average activation energy obtained is 2.25 eV at 50-200 V and 2.60 eV at 200-600 V. In addition, the dynamic R dson is accurately extracted by a unique extraction circuit with high switching frequency up to 1 MHz and high off-state voltage up to 600 V. Meanwhile, the switching times at turn-on and turn-off transitions are captured in a floating buck-boost converter, showing that the transconductance decreases with increasing drain voltage. Furthermore, the effect of parasitic output capacitor on the dynamic R dson is investigated by an experimental method. Finally, a proper hard operating mode is proposed to alleviate the influence of the trapping effect on the performance of switching power converters.INDEX TERMS AlGaN/GaN HEMT, activation energy, dynamic on-resistance, switching time.RUI WANG received the B.S. degree from the School of Nanjing University of Posts and Telecommunications in 2017, and is currently pursuing the Ph.D. degree with the School of Electronic Science and Engineering, Nanjing University. Her research interests mainly focus on the relaibilty research of GaN-based power electronic devices, GaN-based power supply design, and so on.