Patent ID: 8325003

Claim:
A common mode filter, comprising: at least two inductance unit sets, each inductance unit set comprising: an insulating substrate comprising a first surface and a second surface; a coil leading layer disposed on the first surface of the insulating substrate, including at least two leading wires, at least four leading terminals, and at least two contacts, each leading wire connecting a respective one of the leading terminals and a respective one of the contacts; a coil main body layer disposed on the second surface of the insulating substrate, including a coil lead and two end portions thereof; and at least two electrically conductive columns through the insulating substrate, each connecting a respective one of the contacts and a respective one of the two end portions; and an electrically insulating layer bonding the two insulating substrates of the at least two inductance unit sets, bonding the two coil main body layers of the at least two inductance unit sets, electrically isolating the two coil main body layers from each other.