Product Preview
WM8983
HIGHPASS FILTER
The WM8983 has a selectable digital highpass filter in the ADC filter path. This filter has two
modes, audio and applications. In audio mode the filter is a 1st order IIR with a cut-off of around
3.7Hz. In applications mode the filter is a 2nd order high pass filter with a selectable cut-off
frequency.
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Figure 51 ADC Highpass Filter Response, HPFAPP=0
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Figure 52 ADC Highpass Filter Responses (48kHz),
HPFAPP=1, all cut-off settings shown.
Figure 53 ADC Highpass Filter Responses (24kHz),
HPFAPP=1, all cut-off settings shown.
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Figure 54 ADC Highpass Filter Responses (12kHz),
HPFAPP=1, all cut-off settings shown.
PP Rev 1.1 August 2005
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
