Patent ID: 8514022
Filing Date: 2013-08-20
Classification: H01L,H03F

Abstract:
1. A monolithic RF power amplifier integrated in a Si chip comprising: a first transistor and a second transistor each being an active device of a push-pull power amplification circuit; and a transformer being an output matching circuit of the push-pull power amplification circuit, wherein a non-inverted input signal and an inverted input signal can be supplied respectively to an input terminal of the first transistor and an input terminal of the second transistor, wherein the transformer has a primary coil and a secondary coil which are magnetically coupled to each other, wherein a first end and a second end of the primary coil of the transformer are respectively coupled to an output terminal of the first transistor and an output terminal of the second transistor, wherein an output signal can be generated from a first end and a second end of the secondary coil of the transformer, and wherein the primary coil of the transformer includes at least a first coil and a second coil which are coupled in parallel between the output terminal of the first transistor and the output terminal of the second transistor, and are each magnetically coupled to the secondary coil of the transformer, wherein the primary coil and the secondary coil of the transformer are respective metal thin-film wires having respective annular shapes, and each are disposed in a flat shape over a surface of a substrate, and wherein each of the first coil and the second coil of the primary coil of the transformer has a symmetrical shape.