WM8971L Wolfson Microelectronics Ltd., WM8971L Datasheet - Page 55

• Manufacturer Part Number: WM8971L
• Description: Stereo Codec for Portable Audio Applications
• Manufacturer: Wolfson Microelectronics Ltd.

Production Data
Figure 47 De-emphasis Frequency Response (44.1kHz)
Figure 49 De-emphasis Frequency Response (48kHz)
w
HIGHPASS FILTER
The WM8971L has a selectable digital highpass filter in the ADC filter path to remove DC offsets. The filter response is
characterised by the following polynomial:
Figure 51 ADC Highpass Filter Response
-10
-10
-2
-4
-6
-8
-2
-4
-6
-8
-10
-15
0
0
-5
0
0
0
0
5000
5000
0.0005
Frequency (Fs)
Frequency (Fs)
Frequency (Fs)
10000
10000
0.001
H(z) =
0.0015
15000
15000
1 - 0.9995z
1 - z
0.002
20000
20000
-1
Figure 48 De-emphasis Error (44.1kHz)
Figure 50 De-emphasis Error (48kHz)
-1
-0.1
-0.2
-0.3
-0.4
-0.1
-0.2
-0.3
-0.4
0.4
0.3
0.2
0.1
0.4
0.3
0.2
0.1
0
0
0
0
5000
5000
Frequency (Fs)
Frequency (Fs)
10000
10000
PD Rev 4.1 August 2005
15000
15000
WM8971L
20000
20000
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