Wireless Power Transmission to a Mobile Device

In an embodiment, an active stylus includes: an enclosure; a first ferrite core disposed inside the enclosure; a wireless power receiver that includes a first receiving coil wrapped around the first ferrite core between the first ferrite core and the enclosure; and an alignment mark configured to be aligned with a center of a transmitting coil of a wireless power transmitter, where the alignment mark is not align with a center of the first receiving coil.