A Test Circuit for GaN HEMTs Dynamic $R_{\text{ON}}$ Characterization in Power Electronics Applications

Wide bandgap devices such as gallium nitride (GaN) high electron mobility transistors (HEMTs) are a promising technology in the field of power electronics. Due to the physical properties of the GaN and the device design, they can outperform their silicon counterparts for the design of highly efficient power switching converters. However, its design should face certain effects that can diminish its performance. One such effect is the degradation mechanism known as dynamic ON-resistance (dynamic $R_{\mathrm{\scriptscriptstyle ON}}$ ), being its mitigation one of the main objectives in the design of the device. In this paper, a circuit is proposed for assessing if this effect is present in GaN transistors in power electronics applications. The circuit allows testing the GaN HEMTs with different stress voltages and times maintaining the desired current level, and allows for repeating the test in successive switching pulses, with adjustable switching frequency and duty cycle, always with the same current, mimicking a real power electronics application.