WM8978 Wolfson Microelectronics Ltd., WM8978 Datasheet - Page 102
WM8978
Manufacturer Part Number
WM8978
Description
The WM8978 is a low power, high quality stereo codec designed for portable applications such as Digital still camera or Digital Camcorde
Manufacturer
Wolfson Microelectronics Ltd.
Datasheet
1.WM8978.pdf
(108 pages)
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WM8978
5-BAND EQUALISER
Figure 53 EQ Band 1 Low Frequency Shelf Filter Cut-offs
Figure 55 EQ Band 2 – Peak Filter Centre Frequencies,
Figure 57 EQ Band 2 – EQ2BW=0, EQ2BW=1
w
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Frequency (Hz)
Frequency (Hz)
Frequency (Hz)
The WM8978 has a 5-band equaliser which can be applied to either the ADC path or the DAC path.
The plots from Figure 53 to Figure 66 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 54 EQ Band 1 Gains for Lowest Cut-off Frequency
Figure 56
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EQ Band 2 – Peak Filter Gains for Lowest Cut-off
Frequency, EQ2BW=0
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Frequency (Hz)
Frequency (Hz)
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PTD Rev 2.6 November 2005
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Preliminary Technical Data
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