WM8941
Pre Production
HIGHPASS FILTER
The WM8941 has a selectable digital high pass 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 50 ADC High Pass Filter Response, HPFAPP=0
Figure 51 ADC High Pass Filter Responses (48kHz),
HPFAPP=1, all cut-off settings shown.
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Figure 52 ADC High Pass Filter Responses (24kHz),
HPFAPP=1, all cut-off settings shown.
Figure 53 ADC High Pass Filter Responses (12kHz),
HPFAPP=1, all cut-off settings shown.
PP, Rev 3.3, December 2007
90
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
