TLE4997E2 Datasheet, PDF (20/35 Pages) Infineon Technologies AG – Programmable Linear Hall Sensor

TLE4997
Signal Processing
6.4
DSP Input Low Pass Filter
A digital Low Pass Filter is placed between the Hall A/D Converter and the DSP to
reduce the noise level. The Low Pass filter has a constant DC amplification of 0 dB (this
is exactly a gain of 1), which means that its setting has no influence on the internal Hall
A/D Converter value.
The bandwidth can be set in 8 steps.
Table 10 Low Pass Filter Setting
Parameter LP
Cutoff frequency in Hz (at 3dB attenuation)¹⁾
0
78
1
244
2
421
3
615
4
826
5
1060
6
1320
7
off ²⁾
1) _{As this is a digital filter running with an RC-based oscillator, the cutoff frequency may vary within ±25%.}
2) _{The output low pass-interpolation filter behavior remains as main component in the signal path.}
Table 11 Low Pass Filter
Parameter
Symbol Limit Values Unit Notes
min. max.
Register size
LP
3
bit
Corner frequency
∆f
- 25 + 25 %
variation
Note: In Low Pass filter setting 7 (filter off), the output noise increases. Because of
higher DSP load, the current consumption also rises slightly.
Data Sheet
20
V 2.08, 2008-09