摘要 |
A triple winding balun is combined with multiple switch assemblies to implement an antenna switch that provides good isolation, low loss, and good linearity with only a minor increase to the overall chip footprint. The antenna switch also isolates the receiver from power surges, where the power surges may be due to electrostatic discharge, undesirable WiMAX/LTE signals, etc. An exemplary antenna switch comprises a triple winding balun, a first switch subassembly, and an optional second switch subassembly. During stand-by and transmit modes, the first and second switch subassemblies respectively isolate the receiver from transmitter output current and connect a positive voltage bias to the third winding to prevent negative voltage swings at the receiver. During the receive mode, the configuration of the first and second switch subassemblies flips to connect the receiver to the third winding of the balun and to isolate the receiver from power surges. |