wm8974gefl-v Wolfson Microelectronics plc, wm8974gefl-v Datasheet - Page 81

• Manufacturer Part Number: wm8974gefl-v
• Description: Mono Codec With Speaker Driver
• Manufacturer: Wolfson Microelectronics plc

Production Data
Figure 52 EQ Band 2 – Peak Filter Centre Frequencies,
EQ2BW=0
Figure 54 EQ Band 2 – EQ2BW=0, EQ2BW=1
w
5-BAND EQUALISER
Figure 50 EQ Band 1 – Low Frequency Shelf Filter Cut-offs Figure 51 EQ Band 1 – Gains for Lowest Cut-off Frequency
-10
-15
-10
-15
-10
-15
15
10
15
10
15
10
-5
-5
-5
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10
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0
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0
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0
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-1
-1
-2
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10
-1
0
0
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10
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1
1
0
Frequency (Hz)
Frequency (Hz)
Frequency (Hz)
10
10
10
The WM8974 has a 5-band equaliser which can be applied to either the ADC path or the DAC path.
The plots from Figure 50 to Figure 63 show the frequency responses of each filter with a sampling
frequency of 48kHz, firstly showing the different cut-off/centre frequencies with a gain of ±12dB, and
secondly a sweep of the gain from -12dB to +12dB for the lowest cut-off/centre frequency of each
filter.
2
2
1
10
10
10
3
3
2
10
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10
4
4
3
10
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10
5
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4
Frequency, EQ2BW=0
Figure 53 EQ Band 2 – Peak Filter Gains for Lowest Cut-off
-10
-15
-10
-15
15
10
15
10
-5
-5
10
10
5
0
5
0
-1
-1
10
10
0
0
10
10
1
1
Frequency (Hz)
Frequency (Hz)
10
10
2
2
PD, Rev 4.5, September 2008
10
10
3
3
10
10
4
4
WM8974
10
10
5
5
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