Patent ID: 7283793
Filing Date: 2007-10-16
Classification: H04B

Abstract:
1. A transceiver front end circuit comprising: an antenna terminal capable of being coupled to an antenna; a first balun circuit having a single input coupled to the antenna terminal and a pair of balanced outputs coupled to a corresponding pair of balanced receiver inputs, the first balun circuit matching an input impedance of the pair of balanced receiver inputs and substantially phase shifting an input reflection coefficient of the pair of balanced receiver inputs by about 180-degrees; a second balun circuit having a single output coupled to the antenna terminal and a pair of balanced inputs coupled to a corresponding pair of balanced transmitter outputs, the second balun circuit matching an output impedance of the pair of balanced transmitter outputs and substantially phase shifting an output reflection coefficient of the pair of balanced transmitter outputs by about 180-degrees and the first balun circuit and the second balun circuit being contained within a single package; a first shunt switch coupled across the pair of receiver inputs, including a first transistor coupled across the pair of receiver inputs, and a means for increasing a depletion zone of the first transistor when the first shunt switch is open; and a second shunt switch coupled across the pair of transmitter outputs, including a second transistor coupled across the pair of transmitter outputs, and a means for increasing a depletion zone of the second transistor when the second shunt switch is open.