Patent ID: 9696388
Date: 2017-07-04
CPC Classifications: G01R

Claim:
1. A magnetic sensing apparatus, comprising: a reference magnetic field (MF) generating unit, configured to provide a reference MF; an MF sensing unit, configured to sense an external MF and the reference MF to provide an MF sensing signal, wherein the MF sensing signal comprises a first MF sensing signal having a first frequency and a second MF sensing signal having a second frequency, wherein the first frequency is greater than the second frequency; a signal processing unit, coupled to the MF sensing unit and configured to receive and transfer the MF sensing signal into an output signal; a calibration unit, configured to calibrate the output signal according to the MF sensing signal; and a frequency generating unit, coupled to the reference MF generating unit and the MF sensing unit and configured to provide an operating frequency, wherein the reference MF generating unit provides the reference MF according to the operating frequency, and the MF sensing unit senses the external MF and the reference MF according to the operating frequency, wherein the MF sensing unit comprises: