Design of low power UWB LNA based on common source topology with current-reused technique

Abstract

This paper presents two low power UWB LNAs with common source topology. The power reduction is achieved by the current-reused technique. The gain and noise enhancement of the proposed circuit is based on an output buffer which is used by a common source amplifier with shunt–shunt feedback. Chip1 is an adopted T-match input network of 50Ω matching in the required band. Measurements show that the S11 and S22 are less than −10dB, and the maximum amplifier gain S21 gives 9.7dB, and the noise figure is 4.2dB, the IIP3 is −8.5dBm, and the power consumption is 11mW from 1.1V supply voltage. The input matching of chip2 is adopted from a LC high pass filter and source degenerated inductor. The output buffer with the RC-feedback topology can improve the gain, increase the IIP3, restrain the noise, improve the noise figure and decrease the DC power dissipation. Measurements show 13.2dB of power gain, 3.33dB of noise figure, and the IIP3 is −3.3dBm. It consumes 9.3mW from 1.5V supply voltage. These two chips are implemented in a 0.18μm TSMC CMOS process.