Monolithically integrated GaN hysteresis comparator based on complementary logic

A monolithically integrated gallium nitride (GaN) hysteresis comparator based on complementary logic (CL) architecture is demonstrated on a GaN-on-Si platform. The proposed circuit integrates a first-stage comparator, a second-stage inverter buffer, and a feedback network to generate a hysteresis window. At V_DD = 6 V, the fabricated hysteresis comparator achieves an output swing of ∼5.8 V and a hysteresis window of ∼1.5 V. Transient voltage waveforms at critical circuit nodes are measured and analyzed to elucidate the impact of GaN n/p-channel field-effect transistor (n/p-FET) performance mismatch on circuit operation. The analysis reveals that the low current density and threshold voltage shifts of p-FETs limit the switching precision and slew rate. Based on these findings, strategies for performance enhancement are identified from both device processing and circuit design perspectives. These results provide valuable insights for the further development of GaN CL integrated circuits for next-generation power conversion systems.