Title :
Automatic phase alignment for a fully integrated Cartesian feedback power amplifier system
Author :
Dawson, Joel L. ; Lee, Thomas H.
Author_Institution :
Stanford Univ., CA, USA
Abstract :
A phase-alignment system is used in the first reported IC to fully integrate a power amplifier, Cartesian feedback linearization circuitry, and a phase-alignment system. The phase-alignment system consumes 8.8 mW from a 2.5-V supply and employs a new technique for offset-free analog multiplication that enables it to function without manual trimming. Phase alignment of better than 9° is maintained for drifts as large as ±90°. We demonstrate how the phase-alignment system improves the stability margins of the fully integrated Cartesian feedback system. The power amplifier itself, integrated on the same die, operates at 2 GHz and delivers a maximum of 14.2 dBm of output power into a 50-Ω load. The IC was fabricated in a 0.25-μm CMOS process.
Keywords :
CMOS analogue integrated circuits; UHF integrated circuits; UHF power amplifiers; analogue multipliers; feedback amplifiers; 2 GHz; 2.5 V; 8.8 mW; CMOS process; Cartesian feedback power amplifier; automatic phase alignment; chopper stabilization; feedback linearization circuitry; fully integrated amplifier system; offset-free analog multiplication; synchronous downconversion problem; CMOS integrated circuits; Driver circuits; Feedback circuits; Linearization techniques; Manuals; Power amplifiers; Power generation; Radiofrequency amplifiers; Stability; Terminology;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2003.819090
