Theoretical analysis on the automotive electronic compass sensor

In this analysis, the B-H curve was attained and assumed by Z and R type curves. The B/sub max/, H/sub c/, the driving frequency and the demagnetizing factors are considered as parameters to solve a numerical solution. As the driving frequency increased from 4 kHz to 12 kHz-step 4 kHz-the output voltages increased from 147 mV to 446 mV in Z-type. The detection error due to the rotation angles are limited to +3 degrees. In the R type curve, the output voltages are in the range of 145 mV to 354 mV. As the coercive force H/sub c/, is increased, the output voltage increased slightly. Considering the demagnetizing factor, the output voltages are reduced, but the detection error is decreased greatly.