4.9.1 ADC Filters
4.9.1.1 High-Pass Filter
4.9.1.2 Digital Effects Filter - ADC
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TLV320AIC3007EVM Software
Figure 15. ADC High-Pass Filters
The TLV320AIC3007 ADC provides the option of enabling a high-pass filter, which helps to reduce theeffects of DC offsets in the system. The Figure 15 tab shows the options for programming various filterassociated with the ADC. The high-pass filter has two modes: standard and programmable.
The standard high-pass filter option (Figure 16 ) allows for the selection of the high-pass filter frequencyfrom several preset options that can be chosen with the Left ADC HP Filter and Right ADC HP Filtercontrols. The four options for this setting are disabled or three different corner frequencies which arebased on the ADC sample rate.
Figure 16. ADC High-Pass Filter Settings
For custom filter requirements, the programmable function allows custom coefficients to achieve adifferent filter than provided by the preset filters. The controls for the programmable high-pass filter arelocated under the Programmable Filters heading. The following steps describe the process:
1. Enter the filter coefficients in the HP Filter controls near the bottom of the tab.2. Press the Download Coefficients button to download the coefficients to the codec registers.3. Enable the Programmable High-Pass Filters by selecting the Left ADC and Right ADC buttons.
The programmable high-pass filter is now correctly programmed and enabled. The ADC can be enabledwith the high-pass filter.
The ADC digital outputs stream can be routed through the digital effects filter in the codec to allow customaudio performance. The digital effects filter cannot operate on both the ADC or DAC at the same time.The digital effects filter operation is discussed in Section 4.9.3
SLAU286 – June 2009 TLV320AIC3007EVM-K 21Submit Documentation Feedback