US Patent 8068795 RF multiband transmitter with balun

A multi-band RF transmitter circuit (30) for a wireless communication device combines a plurality of RF transmission blocks into a single transceiver integrated circuit which includes a shared broadband SVGA (32), a shared tunable balun (34), and an output switching network (38) at the output of the balun to support three different frequency bands. The outputs of the multi-band RF transmitter circuit are connected to separate external power amplifier circuits (42-44), where each power amplifier circuit generates an amplified signal for one of the plurality of predetermined frequency bands.