A sensor circuit is configured and operated in the presence of interference. In connection with various example embodiments, a stray magnetic field is sensed with current sensors that also respectively sense current-induced magnetic fields generated by current flowing in opposing directions through different portions of a conductor. The current-induced magnetic fields and the stray magnetic field are coplanar, and the current sensors are arranged such that a portion of the output from each current sensor corresponding to the stray magnetic field is canceled when the sensor outputs are combined.