TLE4998S3 Datasheet, PDF (27/39 Pages) Infineon Technologies AG – Programmable Linear Hall Sensor

TLE4998S
Temperature Compensation
8.1
Parameter Calculation
The parameters TC₁ and TC₂ may be calculated by:
TC₁
=
-^T----^L-----–----1---6---0-- × 1000000
65536
TC₂
=
-^T----^Q------–----1---2---8-- × 1000000
8388608
Now the digital output for a given field B_IN at a specific temperature can be calculated by:
OUT
=
2
⋅
⎛
⎜
⎝
--^B-----^I--^N---
B_FSR
×
S_TC
×
S_TCHall
×
S₀
×
⎞
4096⎟
⎠
+ OUT_OS
B_FSR is the full-range magnetic field. It is dependent on the range setting (e.g 100 mT).
S₀ is the nominal sensitivity of the Hall probe times the Gain factor set in the EEPROM.
S_TC is the temperature-dependent sensitivity factor calculated by the DSP.
S_TCHall is the temperature behavior of the Hall probe.
The pre-calibration at Infineon is performed such that the following condition is met:
S_TC(T_J – T₀) × S_TCHall(T_J) ≈ 1
Within the application, an additional factor B_IN(T) / B_IN(T₀) is given due to the magnetic
system. S_TC then needs to be modified to S_TCnew so that the following condition is
satisfied:
--^B----^I--^N----⁽--T----⁾--
B_IN(T₀)
×
S_TCnew(T)
×
S_TCHall(T)
≈
S_TC(T)
×
S_TCHall(T)
≈
1
Therefore, the new sensitivity parameters S_TCnew can be calculated from the pre-
calibrated setup S_TC using the relationship:
--^B----^I--^N----⁽--T----⁾--
B_IN(T₀)
×
S_TCnew(T)
≈
S_TC(T)
Data Sheet
27
V 1.0, 2008-07