A Low-Power Current-Reuse LNA for 3D Ultrasound Beamformers

Yohei NAKAMURA, Shinya KAJIYAMA, Yutaka IGARASHI, Takashi OSHIMA, Taizo YAMAWAKI
2021 IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences  
3D ultrasound imagers require low-noise amplifier (LNA) with much lower power consumption and smaller chip area than conventional 2D imagers because of the huge amount of transducer channels. This paper presents a low-power small-size LNA with a novel currentreuse circuitry for 3D ultrasound imaging systems. The proposed LNA is composed of a differential common source amplifier and a source-follower driver which share the current without using inductors. The LNA was fabricated in a 0.18-µm CMOS
more » ... process with only 0.0056 mm 2 . The measured results show a gain of 21 dB and a bandwidth of 9 MHz. The proposed LNA achieves an average noise density of 11.3 nV/ √ Hz, and the 2nd harmonic distortion below −40 dBc with 0.1-Vpp input. The supply current is 85 µA with a 1.8-V power supply, which is competitive with conventional LNAs by finer CMOS process.
doi:10.1587/transfun.2020gcp0011 fatcat:5bl4rzkiangeziphtp6brxgnyy