TLE4997 Datasheet, PDF (17/36 Pages) Infineon Technologies AG – Programmable Linear Hall Sensor for Industrial Use

TLE4997I
Signal Processing
6
Signal Processing
The flow diagram in Figure 5 shows the data processing algorithm.
Hall
Sensor
Range LP
A
D
Temperature ^TC₂
Sensor
X
A
D
+
Gain
X
1+
X
Limiter
(Clamp)
X₊
D
A
out
Offset
LP_DAC
-T₀
TC₁
X
Temperature
Compensation
Stored in
EEPROM
Memory
Figure 5 Signal Processing Flow
Magnetic Field Path
• The analog output signal of the chopped Hall cell is converted in the continuous-time
A/D Converter. The range of the chopped A/D Converter can bet set in several steps
(see Table 6). This assures a suitable level for the A/D Converter.
• After the A/D conversion, a digital low pass filter reduces the bandwidth (Table 10).
• A multiplier amplifies the value according to the gain setting (see Table 8) plus
temperature compensation.
• The offset value is added (see Table 9).
• A limiter reduces the resulting signal to 12 bits and feeds the D/A converter.
Temperature Compensation
(Details are listed in Chapter 8)
• The output signal of the temperature cell is also A/D converted.
• The temperature is normalized by subtraction of the T₀ value (zero point of the
quadratic function).
• The linear path is multiplied with the TC₁ value.
Data Sheet
17
V 1.0, 2007-06