Methods and apparatus are provided for sensing physical parameters. The
apparatus comprises a magnetic tunnel junction (MTJ) and a magnetic field
source whose magnetic field overlaps the MTJ and whose proximity to the
MTJ varies in response to an input to the sensor. A magnetic shield is
provided at least on a face of the MFS away from the MTJ. The MTJ
comprises first and second magnetic electrodes separated by a dielectric
configured to permit significant tunneling conduction therebetween. The
first magnetic region has its spin axis pinned and the second magnetic
electrode has its spin axis free. The magnetic field source is oriented
closer to the second magnetic electrode than the first magnetic
electrode. The overall sensor dynamic range is extended by providing
multiple electrically coupled sensors receiving the same input but with
different individual response curves and desirably but not essentially
formed on the same substrate.