Analysis and optimization of monolithic inductors and transformers for RF ICs

A fast and accurate approach for analyzing Si IC spiral inductors and transformers is presented. The technique incorporates the substrate in the calculation to fully characterize the devices. Many test structures are fabricated and measured data is used to verify the analysis technique over a broad frequency range. Suitable lumped broadband equivalent circuit models of the structures are presented which can be incorporated into traditional circuit simulators. A custom CAD tool ASITIC is described which is used for the design and optimization of inductors and transformers.