Abstract: A two stage amplifier with an inter-stage matching network constituted of a first and a second transistor forming a differential first stage, a third and a fourth transistor forming a differential second stage, an on-chip connection path connecting the emitters of the first and second transistor to the emitters of the third and fourth transistors, a first transformation network and a second transformation network. A collector of the first transistor is operatively connected to a base of the third transistor by the first transformation network and a collector of the second transistor is operatively connected to a base of the fourth transistor by the second transformation network. At least one resistor is provided in the on-chip connection path to stabilize the input of the third and fourth transistors.

Abstract: An amplifier has a first transistor, a second transistor, a third transistor and a fourth transistor, a first transformation network having first and second grounds and a second transformation network having third and fourth grounds. The amplifier has a collector of the first transistor operatively connected to a base of the third transistor by the first transformation network, a collector of the second transistor operatively connected to a base of the fourth transistor by the second transformation network, the first ground and the third ground are electrically connected to each other, the second ground and the fourth ground are electrically connected to each other, the emitters of the first and of the second transistors are electrically connected to the first ground and the third ground, and the second ground and the fourth ground are electrically connected to the emitters of the third and of the fourth transistors.

Abstract: Sets of power amplifier branches (which comprise an RF/microwave amplifier stage) are power combined within each stage and each set of power amplifier branches are biased in different classes of operation by bias circuits possessing different impedance characteristics such that the fundamental frequency components present at the output are in-phase with one another and the IMD3 components are anti-phase over a broad range of power levels. The RF input signal is provided by the output of the previous stage of the RF/microwave amplifier. The output of each stage is formed by power combining sets of these power amplifier branches, each of which are separately biased, so the fundamental components are additive resulting in the maximum possible output power and the IM3 components cancel partially or completely.

Abstract: Sets of power amplifier branches (which comprise an RF/microwave amplifier stage) are power combined within each stage and each set of power amplifier branches are biased in different classes of operation by bias circuits possessing different impedance characteristics such that the fundamental frequency components present at the output are in-phase with one another and the IMD3 components are anti-phase over a broad range of power levels. The RF input signal is provided by the output of the previous stage of the RF/microwave amplifier. The output of each stage is formed by power combining sets of these power amplifier branches, each of which are separately biased, so the fundamental components are additive resulting in the maximum possible output power and the IM3 components cancel partially or completely.