Infineon TLE4997, User Manual

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TLE4997
User’s Manual
Calibration of TLE4997 Temperature Compensation
User’s Manual 32 v01_01, 2019-08
5.5 Usage of Infineon’s Temperature Calibration Tool
For laboratory calibration purpose, Infineon provides a simple tool to determine the calibration parameters from
measurement data (see
Figure 5-4 ).
The following sequence of steps is used for the temperature calibration the Infineon tool:
1. Measure the sensor’s AOUT and TCAL registers at a fixed magnet position for different temperatures as
described in Chapter 5.3 , enter the T
J
(in °C) and AOUT (in V) values in the table fields marked in yellow (see
Figure 5-4 , upper left side). For the readout of this data, the Infineon TLE4997 Evaluation Kit can be used.
2. The tool automatically calculates the corresponding Sensitivity correction values S from the entered T
J
and
AOUT values according to Equation (5.7) .
3. Based on the calculated S values, the tool performs a quadratic fit and calculates the Application Sensitivity
Polynomial parameters TC1 and TC2 (see Figure 5-4 , upper right side).
Figure 5-4 Infineon tool for temperature calibration, application sensitivity polynomial fit.
4. Readout the sensor’s preprogrammed TL
pre
and TQ
pre
values and enter them in the corresponding table fields
marked in yellow (see Figure 5-5 upper left side). For the readout of this data, the Infineon TLE4997 Evaluation
Kit can be used.
5. The tool calculates the TL
final
and TQ
final
parameters out of the entered TL
pre
and TQ
pre
values, the (fixed) TT
value and the TC1 and TC2 coefficients determined in steps 1-3. For that, an automated script is used that
implements the procedure explained in
Chapter 5.4 . The calculated values TL
final
and TQ
final
appear in the
corresponding table fields marked in green (see Figure 5-5 upper right side)
6. Program the calculated TL
final
and TQ
final
values into the TLE4997 using the Infineon TLE4997 Evaluation Kit
or a suitable programmer tool.
For illustration purpose, the tool also displays graphs for the preprogrammed and final sensitivity polynomials,
S
DSP,pre
and S
DSP,final
, the application sensitivity polynomial S
app
and the product S
DSP,pre
*S
app
. Ideally, after
succesful calibration, S
DSP,final
should by approximately equal S
DSP,pre
*S
app
(compare Equation (5.6) ).
User Parameter Calculation
i T
J
(i) [
°
C]
VOUT
(i)
[V] S
(i)
y = a + bx + cx
2
1 -40 4,45000 1,282 a = 1,31E+00
2 -20 4,43500 1,292 b = 6,55E-04[
°
C
-1
]
3 0 4,41000 1,309 c = 2,14E-06[
°
C
-2
]
4 25 4,39000 1,323
5 50 4,36500 1,340 S
user
= 1 + TC1
user
(T-T0
user
) + TC2
user
(T-T0
user
) 2
6 75 4,32500 1,370 T0
user
= 48[
°
C]
7 100 4,30000 1,389 TC1
user
= 641[ppm/
°
C]
8 120 4,26500 1,416 TC2
user
= 1,59[ppm/ °
C 2 ]
T
J
(i) [
°
C] and VOUT (i) shall be read from the sensor for each data point (T
J
= TCAL/16 + 48)
y = 2,135E-06x
2
+ 6,550E-04x + 1,305E+00
1,26
1,28
1,30
1,32
1,34
1,36
1,38
1,40
1,42
1,44
-50 0 50 100 150
S
en
sit
iv
it
y
co
rr
ec
ti
o
n
S
(T
J
)
T
J
(
°
C)
S(i)
Quadratic fit