Reliability of polynomial I/sub DS/-V/sub GS/-V/sub DS/ model fitted using harmonic-balance simulation

A distortion tear-down analysis technique based on harmonic-balance (HB) simulation and polynomial model fitting has been presented recently. However, the fitting of I/sub DS/-V/sub GS/-V/sub DS/ current source of LDMOS RF power transistor amplifier suffers from high correlation between controlling voltages V/sub GS/ and V/sub DS/. In this paper, the accuracy of the analysis results is discussed, and techniques to improve the reliability of the fitting are presented.