TLE4997 Datasheet, PDF (20/36 Pages) Infineon Technologies AG – Programmable Linear Hall Sensor for Industrial Use

TLE4997I
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⁾
01234567
78 244 421 615 826 1060 1320 off²⁾
1) _{As this is a digital filter running with an RC-based oscillator, the cutoff frequency may vary within ±30%.}
2) _{The output low pass-interpolation filter behavior remains as a main component in the signal path.}
Table 11 Range
Parameter
Symbol Limit Values Unit Notes
min. max.
Register size
LP
3
bit
Corner frequency
∆f
- 30 + 30 %
variation
Note: In Range 7 (filter off), the output noise increases. Because of higher DSP load, the
current consumption also rises slightly.
Data Sheet
20
V 1.0, 2007-06