Design of a reconfigurable gain low noise amplifier for multistandard receivers in 65 nm technology

Abstract

This paper presents a broadband variable gain low noise amplifier (LNA) suitable for multistandard receivers. The LNA has been implemented in 65 nm CMOS technology. To provide low noise input impedance matching, a negative-shunt feedback matching has been proposed. This LNA achieves a simulated noise figure less than 1.94 dBm at the highest gain (25 dB) over a wideband frequency (100 MHz–1 GHZ). Furthermore, the gain of the LNA is variable over a wide range of 11 dB and S11 is less than −19 dB over the entire desired frequency band. The −3 dB bandwidth is 2 GHz, the IIP3 is −6.5 dBm at the highest gain. The LNA drains 18.3 mA from a 1.2 V supply and 7.3 mA from a 2.2 V supply. In addition, a single-ended to differential converter (SDC) is presented providing a differential output for the LNA and increasing the gain re-configurability range to 20 dB.