An inductor-less CMOS broadband balun gm-boosting LNA exploiting noise cancellation techniques

Abstract

This paper presents a 100 MHz to 6 GHz broadband inductor-less single-to-differential balun gm-boosting low-noise amplifier (LNA) for multi-standard radio applications. Two mechanisms of noise cancellation techniques have been innovatively introduced in this work. To achieve the wideband input matching, high gain, and low noise figure simultaneously, a feed-forward thermal noise cancellation technique has been exploited in the design of the inverting amplifier for transconductance enhancement. Moreover, the balanced balun operation transforms the thermal noise of the common-gate transistor into a common-mode signal, and cancels it at the LNA’s differential outputs. The proposed design has been fabricated in a standard 0.18-um RF CMOS technology and occupies a die area of 0.04 mm2. Measurement results have shown that it has achieved a good performance over the whole operation frequency range of interest (100 MHz to 6 GHz) with a gain of 15.5 dB, IIP3 of 1.5 dBm, minimum NF of 3.0 dB and current dissipation of 8 mA at 1.8 V supply voltage.