An X-Band GaN HEMT Low-Noise Amplifier MMIC With Gate-Grounded Self-Biasing for Negative Supply-Free Operation

This letter presents an X-band low-noise amplifier (LNA) monolithic microwave integrated circuit (MMIC) fabricated in a 150-nm GaN-on-SiC high-electron-mobility transistor (HEMT) process. A gate-grounded self-biasing technique is employed to eliminate the negative gate voltage supply typically required for depletion-mode GaN HEMTs. The negative gate–source voltage is generated through the voltage drop across a source resistor, enabling single positive drain supply operation without bias sequencing requirements. The three-stage common-source LNA achieves a gain of over 18.5 dB across the 8.5–11.5-GHz band with a minimum noise figure (NF) of 2.0 dB. The input and output return losses exceed 10 dB from 8.5 to 11.5 GHz. The measured input 1-dB compression point (IP${}_{\text {1$\,$dB}}$) is −16.4 dBm at 10 GHz. The circuit dissipates 234 mW from a 10-V supply, with a chip area of$2840\times 1189~\mu $m2.