Device and methods for high isolation and interference suppression switch-filter

Abstract

Systems and methods are provided for a stacked die configuration of a high isolation switch and a rejection filter where transmit and receive signals are desired to have a high out-of-band rejection and a low loss band-pass region. In some aspects of the invention the high isolation switch is a double pole double throw switch modified to operate as a high isolation single pole double throw (SPDT) switch. In some aspects of the invention the high isolation switch is a conventional high isolation SPDT switch. The switch is mounted on a low profile rejection filter having metallization on a portion of an outer surface of the rejection filter. The metallization on the outer surface of the rejection filter provides an AC ground layer in close proximity to the switch that provides a short coupling path between the switch and the AC ground. The resulting switch-filter component also results in a smaller footprint than if the two devices were mounted individually and/or adjacently. The switch-filter component has applications in devices requiring high isolation between transmit and receive paths, for example use within a front-end module (FEM) of a single antenna, multi-radio device.