CMOS transceiver analog front end having a combined power amplifier and low noise amplifier

摘要

A complementary metal oxide semiconductor transceiver analog front end circuit includes a combined transmit and receive amplifier block that produces an amplified transmit differential signal and receives a receive differential signal through the same pair of input/output nodes coupled to an external network through an RF choke block. In one embodiment the combined transmit and receive amplifier block includes separate power amplifier and low noise amplifier circuits, while a second embodiment includes a power amplification stage and a combined power amplification/low noise amplification stage. The amplifier circuits may be constructed using a combination of thin oxide core transistors and thick oxide input/output transistors. DC feeds may be selected to power the circuits in response to a transmit/receive control signal. Bias voltages to the amplifier circuits' transistors may also be set in response to the transmit/receive control signal.