Patent ID: 7391596

Claim:
A high frequency integrated circuit (IC) pad configuration comprises: a first IC pad to directly couple to an antenna to transmit and receive a high frequency signal; an inductor to operate as a single-ended winding of an inductively coupled balun for direct coupling to the antenna via the first IC pad and electrically disposed on an antenna side of a transmit/receive switch, in which a first node of the inductor is coupled to the first IC pad and the inductor has a desired high impedance at a frequency of the high frequency signal, but the inductor has lower impedance at frequencies of an electrostatic discharge (ESD); a differential winding inductively coupled to the single-ended winding to form the balun with the single-ended winding, the differential winding disposed across a first terminal and a second terminal in which a center tap of the differential winding is coupled to a supply return, the differential winding having a third terminal at a winding tap located between the first terminal and the center tap, and the differential winding also having a fourth terminal at a winding tap located between the second terminal and the center tap, wherein a single balun is used for both transmit and receive modes of operation, in which the first and second terminals are differentially coupled to a low noise amplifier of a receiver and the third and fourth terminals are differentially coupled to a power amplifier of a transmitter; an ESD protection circuit coupled to a second node of the inductor so that the ESD protection circuit is not directly coupled to the first IC pad, in order not to provide loading on the first IC pad; and a second IC pad coupled to the second node of the inductor and to the ESD protection circuit, wherein the second IC pad is to be coupled to another circuit connection having a signal of a lower frequency than the high frequency signal on the first IC pad, so that the ESD protection circuit provides ESD protection to both first and second IC pads.