WM8978_06 Wolfson Microelectronics Ltd., WM8978_06 Datasheet - Page 113

• Manufacturer Part Number: WM8978_06
• Description: Stereo Codec With Speaker Driver
• Manufacturer: Wolfson Microelectronics Ltd.

Pre-Production
5-BAND EQUALISER
Figure 58 EQ Band 1 Low Frequency Shelf Filter Cut-offs
Figure 60 EQ Band 2 – Peak Filter Centre Frequencies,
Figure 62 EQ Band 2 – EQ2BW=0, EQ2BW=1
w
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Frequency (Hz)
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The WM8978 has a 5-band equaliser which can be applied to either the ADC path or the DAC path.
The plots from Figure 58 to Figure 71 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.
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Figure 59 EQ Band 1 Gains for Lowest Cut-off Frequency
Figure 61
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EQ Band 2 – Peak Filter Gains for Lowest Cut-off
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PP Rev 3.0 May 2006
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WM8978
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