The disclosed technology includes a flexible circuit for an end
effector of a medical probe. The flexible circuit includes a flexible substrate, electrodes, and a first sensing ring. The flexible substrate defines fangs extending along a longitudinal axis. Electrodes are disposed on each of the fangs. The first sensing ring is disposed on the flexible substrate. The first sensing ring forms one or more coils that generate a current indicating the position of the one or more coils when the one or more coils are subjected to a
magnetic field. The first sensing ring includes two segments disposed on corresponding fangs, the two segments extending generally parallel to the longitudinal axis and converging towards each other on the fangs disposed on the longitudinal axis.