Patent ID: 6765442
Filing Date: 2004-07-20
Classification: H03F

Abstract:
A circuit comprising:a push-pull power amplifier configured to operate in a switching mode and comprising: a first section coupled to receive a first input signal and a second section coupled to receive a second input signal, wherein each of the first and second sections comprises a metal oxide semiconductor (MOS) transistor, a transistor pair, and a current source providing a bias current to the MOS transistor and the transistor pair, wherein the MOS transistor is coupled to the transistor pair so as to switch the bias current between the MOS transistor and the transistor pair in response to the corresponding input signal; and a signal combiner adapted to receive signals from the first and second sections to drive a load impedance, wherein, when the MOS transistor of the first section switches the bias current to the transistor pair, the transistor pair drives the load impedance through the signal combiner in one direction, and, when the MOS transistor of the second section switches the bias current to the transistor pair, the transistor pair drives the load impedance through the signal combiner in another direction.