Development of W-CDMA RFCMOS Inductively-Degenerated LNAs

A detailed and systematic methodology on the design of the inductively-degenerated LNA, also known as the SNIM LNA, for W-CDMA application is presented in this book. Detailed voltage gain, S-parameters and noise derivations for the SNIM LNA are provided. This is followed by comprehensive circuit analysis, design methodology and performance comparisons of the modified SNIM, namely the PCSNIM, CR and FC LNAs. Results show that for applications with low voltage requirement, the FC offers good linearity at a comparable NF, with gain as the trade-off. CR and matched SNIM are comparable in all of the performance metrics, but matched SNIM posed a disadvantage in terms of space. A PCSNIM with output buffer was designed to maintain the matched conventional PCSNIM noise figure (NF) merit over the SNIM, but with much less layout space consumed by the latter which is better for circuit integration.Good reverse isolation obtained proves the merit of the cascode topology. Comprehensive analysis on the extreme condition effects on the SNIM¿s performance is given with two types of post-layout simulations performed, i.e. with the distributed R+C+CC and the lump parasitic.