Patent attributes
In one embodiment of a wireless power transmitter, two coils are magnetically coupled together by placing both coils on a magnetic layer. A power circuit generates an AC signal of a defined voltage magnitude that causes a current to flow through the first coil, which generates a magnetic field having a first polarity. The second coil is coupled to the first coil. Current flows through the second coil and generates a magnetic field having a second polarity that is opposite from the first polarity. Because the magnetic field generated by each coil has a different polarity, the magnetic fields attract and form a strong magnetic field that flows from the first coil to the second coil. The strong magnetic field can transfer greater amounts of power to a receiver in comparison to coil configurations that emit magnetic fields in the same direction that repel one another.