Modeling the zero and forward bias operation of PIN diodes for high-frequency applications

Silicon-based PIN diodes have been studied in a high-frequency switching application under moderate to high input voltage levels. A model suitable for full circuit simulators such as SPICE is proposed and tested. The model accurately describes the impedance behavior over changes in frequency, DC bias current and applied voltage level. A localized maximum in series resistance is accurately modeled and found to be a function of the diode’s transit time effect. The model also describes the nonlinear high current stored charge-DC bias current effect. The full circuit PIN diode model is verified with experimental observations.