Patent ID: 7978448
Filing Date: 2011-07-12
Classification: H02H,H04B

Abstract:
1. A hybrid device for protecting a radio-frequency input of a communications device from a radio frequency power transmission of a transmitter during a transmit mode of operation, and from electro-static discharge during both a receive mode of operation and the transmit mode of operation, said hybrid device comprising: at least one electro-static discharge protection element connected to the radio-frequency input of the communications device and adapted for diverting a transient associated with the electro-static discharge to a ground; a shunt switching transistor having a drain coupled to the radio-frequency input of the communications device, a source connected to the ground, and a gate connected to a control signal, wherein the control signal turns on the shunt switching transistor when in the transmit mode of operation and turns off the shunt switching transistor when in the receive mode of operation; wherein the at least one electro-static discharge protection element is operational for preventing damaging electro-static discharge whether the shunt switching transistor is on or off; and a matching network coupled between an antenna connection and the drain of the shunt switching transistor, the antenna connection is also coupled to an output of the transmitter,