Design and Modeling of Millimeter-Wave Transformer in Silicon: A Tutorial (Invited)

A comprehensive review of transformer design and modeling techniques in silicon technology is presented in this paper. Compact, distributed and coupled T-line models of the transformer are established and compared in terms of common-mode and differential-mode behaviors. By use of the modeling technique, the bandwidth and the insertion loss of weakly- and strongly-coupled transformers are explored, and corresponding design examples are provided.