Monolithically Integrated GaN Comparator Based on Complementary Logic

A gallium nitride (GaN) two-stage comparator based on complementary logic (CL) architecture is demonstrated and systematically investigated. The comparator features monolithically integrated enhancement-mode n-channel and p-channel GaN field-effect transistors on a commercial p-GaN gate high-electron-mobility transistor (HEMT) platform. Benefiting from energy-efficient CL configuration, the two-stage comparator exhibits rail-to-rail operation from 25 °C to 200 °C with reduced power consumption. The temperature-dependent voltage transfer characteristics, output waveforms, and frequency responses of the fabricated two-stage comparator are studied in detail to reveal limiting factors and corresponding mechanisms of n-/p-FETs on circuit performance. These results can provide valuable insights for the further development of GaN CL integrated circuits (ICs) for next-generation power conversion systems.