Abstract |
GaN-HEMTs as switching devices impress with their very good properties and gain therefore a lot ofattention from the power electronics community. However, some GaN devices may exhibit increasedresistance during on-state due to charge trapping effects. As for designers of switch mode power supplies the internal structure of devices is concealed, measurements are the only way to gain information. This paper shows the measurement of the static on-state resistance of a GaN-HEMT. Furthermore, it quantifies the dynamic on-state resistance by measurement with a novel clamping circuit using a digitizer card with high resolution. Based on these results, it presents an easy to implement method for calculating conduction losses in the presence of dynamic on-state resistance. |