Front end systems and related devices, integrated circuits, modules, and methods

A front end system comprising:

• a low noise amplifier in a receive path of the front end system, the low noise amplifier including (i) an input matching circuit that includes a first inductor and a series inductor, the series inductor having a first end configured to receive a radio frequency signal and a second end electrically connected to the first inductor;
• (ii) an amplification circuit configured to receive the radio frequency by way of the first inductor;
• and (iii) a second inductor magnetically coupled to the first inductor to provide negative feedback to linearize the low noise amplifier;
• and
• a multi-mode power amplifier circuit in a transmit path of the front end system, the multi-mode power amplifier circuit including a stacked output stage including a transistor stack of two or more transistors, and the multi-mode power amplifier circuit including a bias circuit configured to control a bias of at least one transistor of the transistor stack based on a mode of the multi-mode power amplifier circuit.

A wireless communication device comprising:

• a low noise amplifier in a receive path of a front end system, the low noise amplifier including a first inductor, a series inductor having a first end configured to receive a radio frequency signal and a second end electrically connected to the first inductor, an amplification circuit configured to receive the radio frequency signal by way of the first inductor, and a second inductor magnetically coupled to the first inductor to provide negative feedback to linearize the low noise amplifier;
• a multi-mode power amplifier circuit in a transmit path of the front end system, the multi-mode power amplifier circuit including a stacked output stage including a transistor stack of two or more transistors, and the multi-mode power amplifier circuit including a bias circuit configured to control a bias of at least one transistor of the transistor stack based on a mode of the multi-mode power amplifier circuit;
• an antenna;
• and
• a radio frequency switch configured to electrically couple the antenna to the transmit path in a first state and to electrically couple the antenna to the receive path in a second state.