CMOS power amplifiers

Abstract

Accurate MOSFET device modeling is an extremely important procedure to develop low-cost silicon integrated circuits using CMOS technology for higher speed and higher frequency integrated circuits and subsystems within shorter design time. The accuracy of MOSFET models to describe their nonlinear behavior is crucial to predict the entire circuit performance. The lumped-parameter equation-based equivalent circuit model provides a clearer physical description and more design flexibility. The cross section of the MOSFET and substrate coupling networks are shown in Figure 7.1(a). Here, the considerable ohmic loss caused by the semiconductive silicon substrate is characterized by the resistances Rb1, Rb2, and Rsub. The junction capacitance corresponding to source-drain region is represented by the capacitances Cjs and Cjd. The capacitance Cgb represents the gate-to-substrate coupling capacitance consisting of the gate oxide capacitance and the depletion layer capacitance.