Comparison between equivalent-circuit and black-box non-linear models for microwave electron devices

Black-box and equivalent-circuit electron device models present different advantages. The first ones are independent from process and device technology (i.e, GaAs, InP, GaN). In the other side the black-box model extraction procedure could not be changed and modified, thus a "post-tune" procedure is not possible. On the contrary, equivalent circuits are strongly technology dependent, though they are more flexible in the identification procedure. In fact an "optimization" of the extracted model parameters is possible following a trade-off with measured data over a large set of bias conditions and frequencies. In this paper two device models, which represent the two categories, are compared pointing out the differences in the extraction procedures and in the achievable accuracy under small-signal and large-signal operating conditions.