WM8731 / WM8731L
Production Data
0.02
0.01
0
0
-20
-0.01
-0.02
-0.03
-0.04
-0.05
-0.06
-40
-60
-80
-100
0
0.5
1
1.5
2
2.5
3
0
0.05
0.1
0.15
0.2
0.25
Frequency (Fs)
Frequency (Fs)
Figure 47 ADC Digital Filter Frequency Response –Type 2
Figure 48 ADC Digital Filter Ripple –Type 2
0.02
0.01
0
0
-20
-0.01
-0.02
-0.03
-0.04
-0.05
-0.06
-40
-60
-80
-100
0
0.5
1
1.5
2
2.5
3
0
0.05
0.1
0.15
0.2
0.25
Frequency (Fs)
Frequency (Fs)
Figure 49 ADC Digital Filter Frequency Response –Type 3
Figure 50 ADC Digital Filter Ripple –Type 3
ADC HIGH PASS FILTER
The WM8731/L has a selectable digital high pass filter to remove DC offsets. The filter response is
characterised by the following polynomial.
H(z) =
1 – z-1
1 – 0.9995 z-1
PD, Rev 4.9, October 2012
58
w