Patent ID: 8441321
Filing Date: 2013-05-14
Classification: H03F

Abstract:
1. A multi-stage amplifier structure, comprising: a first branch connected to an output node, said first branch including two transistor amplifiers, wherein outputs of the two transistor amplifiers are connected to one another with a quarter wavelength transmission line or circuit equivalent of a quarter wavelength transmission line, wherein the two transistor amplifiers of the first branch comprise, a second branch including at least one further transistor amplifier, an output of which is connected to said output node, said second branch including a partial wavelength transmission line, or circuit equivalent of said partial wavelength transmission line, connected between the output of the further transistor amplifier and the output node wherein the second branch comprises, wherein the multi-stage amplifier structure is configured such that Chireix action takes place between at least one of said transistor amplifiers in the first branch and the at least one further transistor amplifier in the second branch.