TLE5011_11 Datasheet, PDF (19/45 Pages) Infineon Technologies AG – GMR Angle Sensor

TLE5011
Specification
3.5
Calibration
GMR Values
The end-of-line calibration can be accomplished using following sequence:
1. Turn magnetic field 360° left and measure X and Y values
2. Calculate amplitude, offset, phase correction values of left turn
3. Turn further 90° left and 90° back right without measurement
4. Turn magnetic field 360° right and measure X and Y values
5. Calculate amplitude, offset, phase correction values of right turn
6. Calculate mean values of amplitude, offset, phase correction values
The conditions are specified in Table 9.
The values obtained from this sequence must be stored in a non-volatile memory. They are used for the correction
of the read-out X and Y values before the angular calculation.
The resulting angular deviation is calculated using the parameters determined above.
Temperature Measurement
The signal amplitude T₂₅ of the temperature measurement path at the calibration conditions must be measured
and stored.
Calibration Conditions
All errors are related to calibration performed by Infineon under the following conditions:
Table 9 GMR test calibration conditions at IFX
Parameter
Symbol Limit Values
Unit Notes
min.
typ.
max.
Flux density
Temperature
B_CAL
-
30
-
T_CAL
-
25
-
mT
B_Z = 0 mT
°C
3.6
Angle Calculation
3.6.1 Components of the Output Signals
The X and Y signals at the output can be described by the following equations:
A_X : Amplitude of X (= cos) signal
O_X : Offset of X (= cos) signal
ϕ_X : Phase error of X (= cos) signal
X = A_X × cos (α + ϕ_X) + O_X
Y = A_Y × sin (α + ϕ_Y) + O_Y
A_Y : Amplitude of Y (= sin) signal
O_Y : Offset of Y (= sin) signal
ϕ_Y : Phase error of Y (= sin) signal
3.6.2 GMR Error Compensation
Temperature-dependent Offset Value
To increase the accuracy, the temperature-dependent offset drift can be compensated. The temperature of the
chip must be read out. The offset values O_X and O_Y can be described by the following equations.
Final Data Sheet
19
V2.0, 2011-03