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4.11 Filters Tab
TLV320AIC3104EVM Software
Figure 15. Filters Tab
The TLV320AIC3104 has an advanced feature set for applying digital filtering to audio signals. This tab
controls all of the filter features of the TLV320AIC3104. In order to use this tab and have plotting of filter
responses correct, the DAC sample rate must be set correctly. Therefore, the clocks must be set up
correctly in the software following the discussion in
. See
The AIC3104 digital filtering is available to both the ADC and DAC. The ADC has optional high pass
filtering and allows the digital output from the ADC through digital effects filtering before exiting the codec
through the PCM interface. Likewise, the digital audio data can be routed through the digital effects
filtering before passing through the optional de-emphasis filter before the DAC. The digital effects filtering
can only be connected to either the ADC or DAC, not both at the same time.
The
is divided into several areas. The left side of the tab, is used to select between the DAC or
ADC filters and assist in the selection and calculating the desired filter coefficients. The right hand side of
the tab shows a frequency response plot of the digital effects filter selected and the coefficients that are
programmed into the device. The plots show the magnitude and phase response of each biquad section,
plus the combined responses of the two biquad filters. Note that the plot shows only the responses of the
effect filters, not the combined response of those filter along with the de-emphasis and ADC high-pass
filters.
SLAU218 – August 2007
TLV320AIC3104EVM and TLV320AIC3104EVM-PDK
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