An inductorless wideband common-gate LNA with dual capacitor cross-coupled feedback and negative impedance techniques

Abstract

A wideband common-gate (CG) low-noise amplifier (LNA) with dual capacitor cross-coupled (CCC) feedback and negative impedance techniques is presented for multimode multiband wireless communication applications. Double CCC technique boosts the input transconductance of the LNA, and low power consumption is obtained by using current-reuse technique. Negative impedance technique is employed to alleviate the correlation between the transconductance of the matching transistors and input impedance. Meanwhile, it also allows us to achieve a lower noise figure (NF). Moreover, current bleeding technique is adopted to allow the choice of a larger load resistor without sacrificing the voltage headroom. The proposed architecture achieves low noise, low power and high gain simultaneously without the use of bulky inductors. Simulation results of a 0.18-μm CMOS implementation show that the proposed LNA provides a maximum voltage gain of 25.02dB and a minimum NF of 2.37dB from 0.1 to 2.25GHz. The input-referred third-order intercept point (IIP3) and input 1-dB compression point (IP1dB) are better than –7.8dBm and –19.2dBm, respectively, across the operating bandwidth. The circuit dissipates 3.24mW from 1.8V DC supply with an active area of 0.03mm2.