No-switching AC magnetic Hall-effect measurement method

Apparatus for performing a Hall effect measurement of a time-varying magnetic field, the apparatus comprising:

• a Hall effect sensor, wherein the Hall effect sensor provides a first signal proportional to a product of applied current and the time-varying magnetic field, and wherein the Hall effect sensor provides a second signal proportional to the applied current and independent of the time-varying magnetic field;
• an electrical source configured to drive the applied current through the Hall effect sensor, wherein a frequency of the applied current is fA;
• a narrowband electrical detector configured to provide an output Hall effect signal of the apparatus at 2fA, wherein the narrowband electrical detector is preferentially responsive at 2fA relative to fA;
• whereby the output Hall effect signal at 2fA of the apparatus has improved magnetic field sensing accuracy due to suppression of the second signal.