Clemens Valens @ elektormagazine.com discuss about LEM’s new current sensors which do not use the Hall effect make the measurement. Instead they integrate conductors for gradient measurement and provide immunity against the external fields. He writes:
Here are some new integrated circuit transducers for AC and DC isolated current measurement up to 300 KHz that offer full isolation, despite their small size, by integrating the primary conductor for nominal current measurements of up to 30 A. The transducers are mounted directly onto a printed circuit board as SO8 or SO16 SMT devices and support overload currents up to 200 A peak for short durations (1 ms).
New current sensors have no magnetic circuits – [Link]