A new approach to modeling the dynamic behavior of microwave devices based on pulsed measurements, is presented. Both DC and pulsed I/V characteristics of these devices are modeled using a single function derived from an existing and well-established MESFET/HEMT nonlinear static current model. The robust methodology in this work can be applied to other current models and subsequently implemented into a new large-signal circuit as a single current source, capable of accurately predicting both static and small-signal performance of FET devices. © 2006 IEEE.