Patent ID: 7057475

Claim:
A π filter comprising: a primary ferrite choke including, a primary tube of ferrite made of a single piece of ferrite, a primary supply wire received inside the tube of ferrite, and a primary return wire received inside the primary tube of ferrite; and a first primary capacitor coupled between the primary supply wire and ground; a second primary capacitor coupled between the primary return wire and ground; and a third primary capacitor coupled between the primary supply wire and the primary return wire; a redundant ferrite choke including, a redundant tube of ferrite made of a single piece of ferrite, a redundant supply wire received inside the redundant tube of ferrite, and a redundant return wire received inside the redundant tube of ferrite, and a first redundant capacitor coupled between the redundant supply wire and ground; a second redundant capacitor coupled between die redundant return wire and ground; and a third redundant capacitor coupled between the redundant supply wire and the redundant return wire.