MULTI-PRIMARY TRANSFORMER AND POWER AMPLIFIER USED THEREOF

摘要

A transformer with plural primary sides and a power amplifier using the same are provided to improve efficiency of the power amplifier by utilizing a plurality of load resistances in the power amplifier by supplying the plurality of load resistances to the transformer. A multi-primary transformer includes first and second primary sides(701,702) and a secondary side(703). The second primary side is located at both sides of the first primary side. The second primary side is located outside the secondary side. A plurality of primary sides is wound around the secondary side to form the transformer with plural primary sides. Each of the primary sides is asymmetrically arranged with respect to each other. The transformer with plural primary sides is used as a part of a matching circuit of a power amplifier of a wireless communication system required for a plurality of load impedances.