Optimizing isolation and insertion loss of a radio frequency single pole-double-throw switch

Abstract

A single pole double throw (SPDT) switch is fabricated on an integrated circuit (IC) and may comprise two radio frequency (RF) switching devices each having a separate DC blocking capacitor coupled between respective RF switching devices and a common node. A DC connection is provided between the two RF switching devices with a thin electrically conductive line. This thin electrically conductive line provides for increased isolation between the two RF switching devices and decreased insertion loss. The increased isolation and/or decreased insertion loss is accomplished by tuning the thin electrically conductive line through the characteristic impedance of the line when impedance matching conditions are met. Undesired circuit resonance(s) in the SPDT switch may be substantially reduced by using two or more thin electrically conductive lines that further reduce the thin electrically line(s) inductance.