A Drain Lag Model for GaN HEMT based on Chalmers Model and Pulsed S-Parameter Measurements

P. Luo1,2, O. Bengtsson1 and M. Rudolph1,2

Published in:

IEEE MTT-S Int. Microw. Symp. Dig., Honolulu, USA, Jun. 4-9, pp. 240-243 (2017).

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This paper addresses a novel approach to account for trapping effects in the large-signal description of GaN HEMTs. Instead of relying on an internal effective gate voltage, which is not very intuitive, it is investigated how the Chalmers (Angelov) model parameters are altered by trapping. It is verified that such an approach enables reliable load-pull prediction over a wide range of drain bias voltages. In addition, appropriately scaled parameters are shown to allow for a good estimation of large-signal performance even if the model itself misses a dedicated trapping description.

1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany
2 Brandenburg University of Technology, Ulrich. L. Rohde Chair of RF and Microwave Techniques, Siemens-Halske-Ring 14, 03046 Cottbus, Germany

Index Terms:

GaN HEMT modeling, Chalmers model, trapping effects, drain lag, pulsed S-parameter measurements.