RF Switch with Bypass Topology

Abstract

An RF signal switch circuit that allows connection of any of N radio frequency (RF) input terminals to a switch output port, either in an in-circuit mode or in a bypass mode. Embodiments of the invention allow for both a single switch in the series input path while still having the ability to isolate the bypass path from an input matching network. In both modes, the circuit simultaneously exhibits low input insertion loss (and thus a low noise factor) and high bypass mode isolation.

What is claimed is: 
     
         1 . A radio frequency (RF) signal switch, including:
 (a) at least one RF input port, each RF input port having a shunt switch coupled between the RF input port and circuit ground and configured to selectively shunt the RF input port to ground, a bypass switch coupled between the RF input port and a switch output port, and at least one set of in-path connector switches coupled to the RF input port and the shunt switch;   (b) at least one in-circuit path each coupled to a corresponding isolation shunt switch and coupled to a corresponding one set of in-path connector switches, each in-circuit path being configured to be coupled to an input of a corresponding target circuit;   (c) at least one switch return path configured to be coupled to an output of a corresponding target circuit, and being coupled to a corresponding output connector shunt; and   (d) at least one output connector switch coupled to a corresponding one switch return path and to the switch output port.