A CMOS semi-distributed step attenuator with low insertion loss and low phase distortion

Abstract

A semi-distributed step attenuator with low insertion loss and low phase distortion is presented with 0.18 µm BiCMOS process, which is implemented with a step distributed attenuator for 0–7 dB attenuation with low insertion loss and two π-type switched resistive attenuation modules for large attenuation amplitude. The proposed attenuator has a maximum attenuation range of 0–31 dB with 1 dB-increase at the frequency range of 10–20 GHz and involves less than 8.6 dB of insertion loss. The RMS amplitude error and insertion phase at each attenuation state are less than 0.6 dB and 3°, respectively.