Compact Electrothermal Modeling of an X-band MMIC

Compact electrothermal modeling of lumped electrical devices and compact thermal modeling of volumetric materials enables efficient electrothermal modeling of microwave circuits. The compact thermal model of the body of an X-band MMIC is based on analytical solutions of the heat diffusion equation in thermal sub-volumes. The model is accurate and captures thermal nonlinearities. The model considers complex MMIC features such as surface metallization and vias, as well as the mounting configurations including lead-frame, carrier, and printed circuit board. This is coupled with electrothermal models of transistors and of resistors. The models are incorporated in a multi-physics simulator that uses the same model in both transient and harmonic analysis of an X-band LNA MMIC. Simulations are validated with steady-state thermal measurements