Triple inductor transformer for multiband radio frequency integrated circuits

A transformer, comprising:

• first means for storing energy in a magnetic field, the first energy storing means being accessible via a first port;
• second means for storing energy in a magnetic field, the second energy storing means magnetically coupled to the first energy storing means, the second energy storing means being accessible via a second port, the second energy storing means comprising a first portion configured to permit current flow in a clockwise direction and a second portion configured to permit current flow in a counter-clockwise direction;
• and
• third means for storing energy in a magnetic field, the third energy storing means magnetically coupled to the first energy storing means and to the second storing means, the magnetic coupling between the third storing means and the second storing means being represented by a magnetic coupling coefficient, the third energy storing means being accessible via a third port, in which the counter-clockwise direction is opposite the clockwise direction to reduce the magnetic coupling coefficient to less than 0.1 between the second energy storing means and the third energy storing means based on magnetic coupling cancellation,
• wherein the second storing means is shaped in accordance with a figure eight configuration and in which the second storing means overlaps the first energy storing means and/or the third energy storing means.