A magnetic transducer including an electrically conductive shield (ECS)
which is disposed between the substrate and first magnetic shield is
described. The ECS is preferably embedded in an insulating undercoat
layer. The ECS is preferably electrically isolated from the magnetic
sensor element and is externally connected to a ground available in the
disk drive through the arm electronics. Two alternative ways for
connecting the ECS to a ground are described. In one embodiment which is
only effective with single-ended input type arm electronics, the ECS is
connected to a ground through a via to a lead pad for the read head which
is connected to the ground of the arm electronics. In a second and more
preferred embodiment a separate lead pad is included on the head to allow
the ECS to be connected to electronic or case ground when the head is
installed in the arm. The extent of the ECS should be sufficiently large
to cover the read head portion of the transducer, i.e., from the edge of
the first magnetic shield to the outer edges of the read contact pads, but
should preferably not cover the write head pads.
