A SAW-less CMOS TX for EGPRS and WCDMA

Abstract

A 90 nm CMOS TX path architected for operation without inter-stage SAW filters is shown. The SAW elimination strategy is purely low noise design but the architecture still achieves DG.09 weighted TX current drain of 50 mA from the battery. The combination of a passive interleaved switching mixer plus digital gain control allows 2% EVM at 2 dbm and 4.2% at −78 dbm.