Magnetic sensor assembly

Medical position sensing apparatus, comprising:

• one or more field generators, which are arranged to generate a magnetic field;
• a probe for insertion into a patient, the probe comprising sensor assembly, comprising:
• a first magneto-resistive field sensor in a first surface-mountable package, which is arranged to measure first and second components of the magnetic field projected onto respective different first and second axes with respect to a spatial orientation of the first field sensor and to produce first position signals indicative of the measured first and second components;
• a second magneto-resistive field sensor in a second surface-mountable package, which is arranged to measure at least a third component of the magnetic field projected onto at least a third axis with respect to the spatial orientation of the second field sensor, and to produce second position signals indicative of the measured third component;
• and
• a substrate assembly having the first and second field sensors surface-mounted thereon, which is coupled to orient the first field sensor in a first spatial orientation and to orient the second field sensor in a second spatial orientation, so that the third axis is oriented out of a plane containing the first and second axes;
• and
• a control module, which is arranged to receive and send the first and second position signals and a processing unit for receiving the first and second position signals and to calculate a spatial position of the sensor assembly with respect to the one or more field generators responsively to the position signals by calculating up to six-dimensional coordinate information of the probe.