A Highly Linear and Efficient Differential CMOS Power Amplifier With Harmonic Control
- 30 May 2006
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Journal of Solid-State Circuits
- Vol. 41 (6), 1314-1322
- https://doi.org/10.1109/jssc.2006.874276
Abstract
A 2.45 GHz fully differential CMOS power amplifier (PA) with high efficiency and linearity is presented. For this work, a 0.18-/spl mu/m standard CMOS process with Cu-metal is employed and all components of the two-stage circuit except an output transformer and a few bond wires are integrated into one chip. To improve the linearity, an optimum gate bias is applied for the cancellation of the nonlinear harmonic generated by g/sub m3/ and a new harmonic termination technique at the common source node is adopted along with normal harmonic termination at the drain. The harmonic termination at the source effectively suppresses the second harmonic generated from the input and output. The amplifier delivers a 20.5dBm of P/sub 1dB/ with 17.5 dB of power gain and 37% of power-added efficiency (PAE). Linearity measurements from a two-tone test show that the power amplifier with the second harmonic termination improves the IMD3 and IMD5 over the amplifier without the harmonic termination by maximally 6 dB and 7 dB, respectively. Furthermore, the linearity improvements appear over a wide range of the power levels and the linearity is maintained under -45 dBc of IMD3 and -57dBc of IMD5 when the output power is backed off by more than 5dB from P/sub 1dB/. From the OFDM signal test, the second harmonic termination improves the error vector magnitude (EVM) by over 40% for an output power level satisfying the 4.6% EVM specification.Keywords
This publication has 19 references indexed in Scilit:
- A capacitance-compensation technique for improved linearity in CMOS class-AB power amplifiersIEEE Journal of Solid-State Circuits, 2004
- Accurate small-signal model and its parameter extraction in RF silicon MOSFETsPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2003
- A 2.4-ghz 0.18-μm cmos self-biased cascode power amplifierIEEE Journal of Solid-State Circuits, 2003
- Linearity analysis of CMOS for RF applicationIEEE Transactions on Microwave Theory and Techniques, 2003
- A 5-GHz CMOS transceiver for IEEE 802.11a wireless LAN systemsIEEE Journal of Solid-State Circuits, 2002
- An improved de-embedding technique for on-wafer high-frequency characterizationPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- Monolithic transformers for silicon RF IC designIEEE Journal of Solid-State Circuits, 2000
- Large- and small-signal IMD behavior of microwave power amplifiersIEEE Transactions on Microwave Theory and Techniques, 1999
- A nonlinear microwave MOSFET model for SPICE simulatorsIEEE Transactions on Microwave Theory and Techniques, 1998
- A three-step method for the de-embedding of high-frequency S-parameter measurementsIEEE Transactions on Electron Devices, 1991