WM8750BL Datasheet, PDF (54/59 Pages) Wolfson Microelectronics plc – Stereo CODEC for Portable Audio Applications

WM8750BL
0
0.4
0.3
-2
0.2
0.1
-4
0
-6
-0.1
-0.2
-8
-0.3
-10
0
5000
10000
Frequency (Fs)
15000
20000
Figure 45 De-emphasis Frequency Response (44.1kHz)
0
-0.4
0
5000
10000
Frequency (Fs)
Figure 46 De-emphasis Error (44.1kHz)
0.4
0.3
-2
0.2
0.1
-4
0
-6
-0.1
-0.2
-8
-0.3
-10
0
5000
10000
Frequency (Fs)
15000
Figure 47 De-emphasis Frequency Response (48kHz)
20000
-0.4
0
5000
10000
Frequency (Fs)
Figure 48 De-emphasis Error (48kHz)
Pre-Production
15000
20000
15000
20000
HIGHPASS FILTER
The WM8750BL has a selectable digital highpass filter in the ADC filter path to remove DC offsets. The filter response is
characterised by the following polynomial:
H(z) =
1 - z^-1
1 - 0.9995z^-1
0
-5
-10
-15
0
0.0005
0.001
0.0015
Frequency (Fs)
Figure 49 ADC Highpass Filter Response
0.002
w
Pre-Production Rev 3.3 January 2007
54