Electronic device having electronic compass with demagnetizing coil and annular flux concentrating yokes

Apparatus, comprising:

• a substrate;
• an elongated ring-shaped magnetic flux concentrating yoke on the substrate;
• first and second elongated thin-film magnetoresistance sensors on the substrate extending along opposing sides of the elongated ring-shaped magnetic flux concentrating yoke.

A method of operating an electronic device having an electronic compass with magnetic sensors, comprising:

• with control circuitry in the electronic device, determining whether magnetic sensor sensitivity updates are desired for the magnetic sensors of the electronic compass;
• and
• in response to determining that magnetic sensor sensitivity updates are desired, using the control circuitry to apply a direct current (DC) current to a coil in the electronic device and making calibrating magnetic sensor measurements with the magnetic sensors while the DC current is being applied.