Figure 7-5 Magnetic Response for a 360° Input Field

Figure 7-5 shows the response of the differential-ended AMR output signals and the Hall outputs (Q₁, Q₀) for a 360° input magnetic field (B_IN).

An example code for extending the angle range from 180 degrees to 360 degrees using the Q0, Q1 outputs is given below ;

MeasuredAngle = arctan2(SIN, COS)/2 ; //0-180° angle range , Multiply by 180/Pi if the angle is returned in radians

MeasuredAngle = 90 - MeasuredAngle // If arctan2 function returns from -90deg to 90deg angle range, then use this to convert to 0-180° angle range

if (MeasuredAngle is between 45°–135°) then

(

if (Q1_Q0 is 00b or 10b) then //around 90°

   AbsAngle = MeasuredAngle ;

else //Q1_Q0 is 11b or 01b, around 270°

   AbsAngle = MeasuredAngle + 180°;

)

else //MeasuredAngle is 0°–45° or 135°-180°

(

if (Q1_Q0 is 00b or 01b) then //around 0°

(

if (MeasuredAngle ≥ 135°) then

AbsAngle = MeasuredAngle + 180°;

      else  
        //MeasuredAngle is 0-45°

AbsAngle = MeasuredAngle;

)

   else   
        //2Digital is 10b or 11b, around 180°

(

if (MeasuredAngle ≥ 135°) then

AbsAngle = MeasuredAngle;

      else  
        //MeasuredAngle is 0-45°)

AbsAngle = MeasuredAngle + 180°;

)