Low‐power fully‐differential 3.5‐GHz wideband CMOS LNA

Abstract

AbstractThis article presents a low‐power fully‐differential 3.5‐GHz wideband complementary metal oxide semiconductor (CMOS) low‐noise amplifier (LNA) based on the LC‐ladder match network approach. To have low power consumption and high power gain, two common‐source stages are cascaded for reusing the bias current. To have wideband low noise figure, the gate width of the input transistor is determined from the wideband optimization of noise contribution. The implemented 0.18‐μm CMOS differential LNA achieves a power gain of 12 dB, a minimum noise figure of 3.0 dB, an input‐referred third‐order intercept point of −3.2 dBm, and a 3‐dB bandwidth of 2.5–4.5 GHz, while consuming 12.9 mW. Compared with the other wideband differential LNAs tailored for the same frequency range, a very high figure‐of‐merit of 0.36 is achieved. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1196–1198, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23321