A9.8–30.1GHzCMOSlow-noise amplifier with a 3.2-dB noise figure using inductor- and transformer-based g_m-boosting techniques

Abstract

A 9.8–30.1 GHz CMOS low-noise amplifier (LNA) with a 3.2-dB minimum noise figure (NF) is presented. At the architecture level, a topology based on common-gate (CG) cascading with a common-source (CS) amplifier is proposed for simultaneous wideband input matching and relatively high gain. At the circuit level, multiple techniques are proposed to improve LNA performance. First, in the CG stage, loading effect is properly used instead of the conventional feedback technique, to enable simultaneous impedance and noise matching. Second, based on in-depth theoretical analysis, the inductor- and transformer-based g_m-boosting techniques are employed for the CG and CS stages, respectively, to enhance the gain and reduce power consumption. Third, the floating-body method, which was originally proposed to lower NF in CS amplifiers, is adopted in the CG stage to further reduce NF. Fabricated in a 65-nm CMOS technology, the LNA chip occupies an area of only 0.2 mm² and measures a maximum power gain of 10.9 dB with −3 dB bandwidth from 9.8 to 30.1 GHz. The NF exhibits a minimum value of 3.2 dB at 15 GHz and is below 5.7 dB across the entire bandwidth. The LNA consumes 15.6 mW from a 1.2-V supply.

Keywords

CMOS / g_m-boosting / Low-noise amplifier / Transformer / Common-gate

RIGHTS & PERMISSIONS

2021 Zhejiang University Press