An exact lumped‐element equivalent circuit model for transmission‐line transformers formed from coupled microstrip lines

This paper introduces an exact lumped-element equivalent circuit model for Ruthroff transmission-line transformers (TLTs) constructed from coupled microstrip lines. Measured results are compared with model predictions from 0.01 GHz up to 16.7 GHz for the case of three spiral TLTs fabricated in a silicon multichip-module-deposited (MCM-D) process. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2983–2988, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22939