Patent ID: 7626384

Claim:
Magneto-resistive sensor, comprising: a first plurality of first magneto-resistive elements; a second plurality of second magneto-resistive elements; a first signal processing unit which is connected to the first plurality of first magneto-resistive elements for generating a first output signal; wherein the first output signal has a first phase; a second signal processing unit which is connected to the second plurality of second magneto-resistive elements for generating a second output signal; wherein the second output signal has a second phase; wherein the sensor has an operation mode and a test mode; a third signal processing unit for processing the first and second output signals; wherein the third signal processing unit is adapted to activate one of the operation mode and the test mode on the basis of the first and second output signals; and wherein, when the first and second plurality of first and second magneto-resistive elements are exposed to an homogeneous magnetic field, the third signal processing unit is adapted to activate the test mode.