Time domain large signal characterization of self-biasing phenomena in switch-mode AlGaN/GaN HEMTs

This paper proposes experimental studies and measurement techniques for AlGaN/GaN FET transistors in switch-mode applications. The main contribution is the demonstration of self-biasing effects due to drain and gate loads. To achieve this, RF large signal excitation has been applied at the FET drain port, with the device mounted in shunt configuration. Time-domain large signal characterizations have been performed with a Nonlinear Vector Network Analyser (NVNA), and special care has been given to load lines in both ON- and OFF-states. Validation of experiments has been done with a FET nonlinear model operating in positive and negative drain current.