Patent ID: 7411449
Filing Date: 2008-08-12
Classification: H03F

Abstract:
1. A method of driving a composite power amplifier having a first power amplifier entity and a first power amplifier entity pair, in turn including a second and a third power amplifier entity, the first, second and third power amplifier entities being connected to a common signal input over a control network and to a common load output over a combiner network, the method comprising the steps of: determining a momentary amplitude of an input signal of the signal input and correlating the momentary input signal amplitude to a momentary output voltage amplitude; and driving the first power amplifier entity with the input signal; and, restricting the second and third power amplifier entities at momentary output voltage amplitudes below a first output voltage amplitude to deliver less current than a linearly increasing current function defined by zero current at zero momentary output voltage amplitude and a minimum required current at a momentary output voltage amplitude equal to a maximum linear output voltage that can be achieved with the first, second and third amplifier entities when the second and third amplifier entities deliver current with substantially 180 degrees phase difference;