Skyworks Solutions, Inc.
Transmit loopback path architecture

Abstract:

A front end module with transmit loopback functionality has a transmit loopback path that is configured to conduct a loopback signal from an output of a power amplifier to a receive port, and a receive path that is configured to conduct a radio frequency receive signal from an antenna port to the receive port. The transmit loopback path includes a first switch coupled between the output of the power amplifier and the receive port. The receive path includes a second switch coupled between the antenna port and the receive port, where the receive path is without the first switch.