A COMPACT BROADBAND TRANSFORMER-BASED LINEAR CMOS POWER AMPLIFIER DESIGN

A novel broadband transformer-based CMOS power amplifier (PA) design method is studied in this article. To obtain a broadband PA, the parasitic parameters of the transformer are absorbed into the PAs load match and their impacts on bandwidth are studied. The fully-integrated PA combined with an 8-shaped transformer is implemented in 0.13 mu m CMOS process with only 1.2 x 1.2 mm(2) chip size and operates at Class AB mode. The single-stage PA delivers 27.36 dBm output power with 27% efficiency and has 10.5 dB gain. It has 500 MHz bandwidth (1 dB degeneration) in the large and small signal measurements. IMD3 and IMD5 are also lower than -25 dBc at 19 dBm across the bandwidth. The spectrum of PA can meet the m-WiMAX spectrum mask at 19 dBm average power level. (C) 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:422-425, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25731