A Single-Transistor Amplifier With Back-Gate Feedback in 22-nm FD-SOI

Fully-depleted silicon-on-insulator (FD-SOI) technology provides an additional degree of circuit design freedom due to its fourth terminal, the back-gate (BG). In this letter, we present a single-transistor common-source amplifier exploiting the FD-SOI BG as a feedback injection point. This negative BG feedback improves linearity and reduces device-to-device gain variation without increasing noise or power and with no added components. A prototype amplifier, implemented in 22-nm FD-SOI, operates from weak to moderate inversion and achieves 5–10
$\times $
lower gain variation and 6–20-dB higher VIP
₃
compared to a reference two-transistor amplifier with a diode-connected load.