A unified approach to charge-conservative capacitance modelling in HEMTs

The voltage dependence of high electron mobility transistor (HEMT) gate-source- and gate-drain capacitance is described by a set of equations based on a unified charge-conservative model approach. The model is applied to a low-noise GaAs pseudomorphic-HEMT (pHEMT) technology as well as its power variant. In terms of topology and parameters, the new expressions resemble the Curtice drain current model. They provide a globally accurate description of nonlinearities in HEMT capacitance.