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

摘要

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.

主权项

1. A radio frequency (RF) single-pole-double-throw (SPDT) switch, comprising:
a first node; a first RF switching device; a second RF switching device; a first direct current (DC) blocking capacitor coupled between the first node and the first RF switching device; a second DC blocking capacitor coupled between the first node and the second RF switching device; a second node; a third DC blocking capacitor coupled between the second node and the first RF switching device; a third node; a fourth DC blocking capacitor coupled between the third node and the second RF switching device; and a thin electrically conductive line having a first end coupled between the first DC blocking capacitor and the first RF switching device, and a second end thereof coupled between the second DC blocking capacitor and the second RF switching device, wherein the thin electrically conductive line provides a DC path between the first and second RF switching devices.