Patent ID: 7197284

Claim:
A transceiver circuit comprising: a transmission amplifier coupled with an antenna input/output node wherein the transmission amplifier is configured to amplify communications to be transmitted from the transceiver circuit; a receiver including a receiver input coupled with the antenna input/output node; a capacitor coupled between the antenna input/output node and an electrical reference; a field effect transistor being integrated on a same semiconductor chip as the transmission amplifier and being coupled between the receiver input and the electrical reference wherein the field effect transistor is configured to provide an open circuit when receiving communications at the receiver input and wherein the field effect transistor is configured to provide a closed circuit when not receiving communication at the receiver input; a PIN diode coupled between the transmission amplifier and the antenna input/output node and between the transmission amplifier and the receive input, the PIN diode adapted to isolate the transmission amplifier from the antenna input/output node and isolate the transmission amplifier from the receive input; and a bias circuit coupled with the antenna input/output node wherein the bias circuit is configured to provide a low impedance at the PIN diode when transmitting communications from the transmission amplifier and to provide a high impedance at the PIN diode when communications are not being transmitted from the transmission amplifier, the bias circuit adapted to provide a path in the transmit mode to the antenna input/output node via a microstrip coupled to the receiver input, wherein the capacitor, the microstrip and the closed field effect transistor provide a high impedance.