A 22-to-47 GHz 2-Stage LNA With 22.2 dB Peak Gain by Using Coupled L-Type Interstage Matching Inductors

Abstract

This article presents a 22–47 GHz wideband low-noise amplifier (LNA) with coupled L-type interstage matching inductors. The coupled inductors extend the bandwidth of LNA by moving zeros to lower frequencies to cancel the effect of poles. Meanwhile, asymmetric L-type inductors with different inductances can be designed separately to achieve better gain flatness. In addition, the quality factor of coupled inductors is also slightly improved without significantly changing their inductance. The LNA is fabricated in a 0.13- $\mu \text{m}$ SiGe BiCMOS technology, and it occupies a core area of 0.13 mm2. The LNA achieves a peak gain of 22.2 dB with the 3dB bandwidth of 22–47 GHz (fractional bandwidth up to 72.5%). The measured NF varies between 3.0 and 4.3 dB from 22 to 47 GHz. The measured input 1-dB gain compression point is stable from −23.9 to −22.6 dBm in the entire 3-dB gain bandwidth. The chip consumes a total power of 9.5 mW from a 1.2 V supply.