Fully integrated CMOS power amplifier design using the distributedactive-transformer architecture

摘要

A novel on-chip impedance matching and power-combining method, thendistributed active transformer is presented. It combines severalnlow-voltage push-pull amplifiers efficiently with their outputs innseries to produce a larger output power while maintaining a 50-Ωnmatch. It also uses virtual ac grounds and magnetic couplingsnextensively to eliminate the need for any off-chip component, such asntuned bonding wires or external inductors. Furthermore, it desensitizesnthe operation of the amplifier to the inductance of bonding wires makingnthe design more reproducible. To demonstrate the feasibility of thisnconcept, a 2.4-GHz 2-W 2-V truly fully integrated power amplifier withn50-Ω input and output matching has been fabricated usingn0.35-Μm CMOS transistors. It achieves a power added efficiency (PAE)nof 41 % at this power level. It can also produce 450 mW using a 1-Vnsupply. Harmonic suppression is 64 dBc or better. This new topologynmakes possible a truly fully integrated watt-level gigahertz rangenlow-voltage CMOS power amplifier for the first time