Monolithic Comparators using E/D-mode AlGaN/GaN MIS-HEMTs for High-temperature Applications

AlGaN/GaN metal-insulator-semiconductor high-electron-mobility-transistors (MIS-HEMT) in enhancement (E-) and depletion (D-) modes are monolithically integrated on an intelligent integrated circuit (IC) platform to form the basic circuit modules-the comparators. The comparator circuit operates over different voltage ranges by varying the DIE-mode type of the differential input pair. The transfer characteristics of E/D mode MIS-HEMT comparators are shown at room temperature and high temperatures up to 200°C. The results indicate that the proposed comparators with different E/D operating modes correspond to different operating ranges, implementing logic conversion for −8 to 0 V and 0 to 5 V, respectively. The results of these comparators demonstrate the feasibility and flexibility of the structure and provide additional options for monolithic integration for the all-GaN power platform.