4.9 Filters Tab
TLV320AIC3007EVM Software
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Figure 14. Filters Tab
The TLV320AIC3007 has an advanced feature set for applying digital filtering to audio signals. This tabcontrols all of the filter features of the TLV320AIC3007. In order to use this tab and have plotting of filterresponses correct, the DAC sample rate must be set correctly. Therefore, the clocks must be set upcorrectly in the software following the discussion in Section 4.6 . See Figure 14 .
The AIC3007 digital filtering is available to both the ADC and DAC. The ADC has optional high-pass (HP)filtering and allows the digital output from the ADC through digital effects filtering before exiting the codecthrough the PCM interface. Likewise, the digital audio data can be routed through the digital effectsfiltering before passing through the optional de-emphasis filter before the DAC. The digital effects filteringcan only be connected to either the ADC or DAC, not both at the same time.
The Figure 14 is divided into several areas. The left side of the tab, is used to select between the DAC orADC filters and to assist in the selection and calculating of the desired filter coefficients. The right side ofthe tab shows a frequency response plot of the digital effects filter selected and the coefficients that areprogrammed 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 theeffect filters, not the combined response of those filter along with the de-emphasis and ADC high-passfilters.
20 TLV320AIC3007EVM-K SLAU286 – June 2009Submit Documentation Feedback