GaN High-Electron Mobility Transistor Track-and-Hold Sampling Circuit With Over 100-dB Signal-to-Noise Ratio

A track-and-hold sampling circuit (THSC) fabricated in gallium nitride (GaN) high-electron mobility transistor (HEMT) on silicon carbide substrate is presented for the first time, considering the impact of GaN HEMT memory effects on the sampled signal. A single-transistor GaN track-and-hold sampler with an external gate-bootstrapping sampling clock demonstrates over 100-dB signal-to-noise ratio with 700-MHz track-mode bandwidth.