A CMOS low noise transconductance amplifier for 1-6 GHz bands

The linearity and noise requirements in multi-band multi-standard applications make the design of RF CMOS circuits a very challenging task. A low noise transconductance amplifier (LNTA) in 130 nm CMOS technology that operates between 1 and 6 GHz is presented. The LNTA is based on a shunt-feedback (SFB) amplifier with current-reuse scheme and employing the noise-canceling technique used in low-noise amplifier designs for wideband input matching. Two versions of the LNTA were designed in a 130 nm CMOS process and occupy 0.038 and 0.014 mm(2) of silicon area while consuming just 9.1 and 7.94 mW, respectively. The second version is an inductorless, smaller, and optimized version of the first one. Post-layout simulations in the temperature range of -40 to 125 A degrees C show a good trade-off between noise and power-consumption across the frequency span with an average noise figure of 3.8 dB and a minimum transconductance of 41.5 mS over the entire band. Performance variations were estimated at 2 GHz with Monte Carlo analysis.