Low-power magnetometer assemblies with high offset stability

A method for operating an assembly that comprises a first magnetometer sensor and a second magnetometer sensor, the method comprising:

• determining a difference between a current signal measurement output component of a current output of the first magnetometer sensor and a previous signal measurement output component of a previous output of the first magnetometer sensor;
• comparing the determined difference with a current threshold value;
• and
• generating an assembly output based on the comparing, wherein:
• when the determined difference is greater than the current threshold value based on the comparing, the generating comprises providing a first assembly output using a current offset output component of a current output of the second magnetometer sensor;
• when the determined difference is less than the current threshold value based on the comparing, the generating comprises providing a second assembly output using a previous offset output component of a previous output of the second magnetometer sensor;
• and
• the first magnetometer sensor operates with a lower power consumption than the second magnetometer sensor.

A method for operating an assembly that comprises a first magnetometer sensor and a second magnetometer sensor, the method comprising:

• determining an output difference between a new output of the first magnetometer sensor and a previous output of the first magnetometer sensor;
• accessing a current threshold;
• comparing the determined output difference with the accessed current threshold;
• selectively updating a value of a stored offset based on the comparing, wherein the selectively updating comprises:
• not changing the value of the stored offset when the determined output difference is not greater than the accessed current threshold based on the comparing;
• and
• changing the value of the stored offset when the determined output difference is greater than the accessed current threshold based on the comparing, wherein the changing comprises:
• determining a sensor difference between the new output of the first magnetometer sensor and a new output of the second magnetometer sensor;
• and
• storing the determined sensor difference as the value of the stored offset;
• and
• after the selectively updating, generating an assembly output using the new output of the first magnetometer sensor and the value of the stored offset, wherein the changing further comprises de-activating the second magnetometer sensor after the determining the sensor difference and before the generating the assembly output.

A hybrid magnetometer sensor assembly comprising:

• a first magnetometer sensor;
• and
• a second magnetometer sensor, wherein the assembly is operative to:
• re-center a transfer function of the first magnetometer sensor using an offset output component of an output of the second magnetometer sensor;
• and
• generate an assembly output using the re-centered transfer function and a signal measurement output component of an output of the first magnetometer sensor, wherein the first magnetometer sensor operates with a lower power consumption than the second magnetometer sensor.