A variable gain wideband CMOS low-noise amplifier for 75 MHz–3 GHz wireless receivers

Abstract

A wideband CMOS variable gain low noise amplifier suitable for multi-standard radio applications between 75 MHz and 3 GHz is presented. Wideband matching to 50 Ohm (single ended) is achieved using a common-drain feedback stage whereas variable gain is realized using a resistive attenuator. The circuit has been designed in a 65 nm CMOS process and achieves 22 dB maximum gain, 29 dB gain range, 3.3 dB noise figure, and an IIP3 higher than -4 dBm.