TLV320AIC3109EVM Software
23
SLAU738 – September 2017
Copyright © 2017, Texas Instruments Incorporated
TLV320AIC3109EVM-K
4.8.1
ADC Filters
4.8.1.1
High Pass Filter
The TLV320AIC3109-Q1 ADC provides the option of enabling a high-pass filter, which helps to reduce the
effects of DC offsets in the system. The ADC high-pass filter tab is shown in
. This tab shows the
options for programming various filter associated with the ADC. The high-pass filter has two modes:
standard and programmable.
The standard high-pass filter option allows the selection of the high-pass filter frequency from several
preset options that can be chosen with the
ADC HP Filter
control. Four options are available for this filter
setting, one for disable and other three different corner frequencies which are based on the ADC sample
rate.
For custom filter requirements, the programmable function allows custom coefficients to achieve a
different filter than provided by the preset filters. The controls for the programmable high-pass filter are
located under the
Programmable Filters
heading. The process should use the following steps:
1. The filter coefficients can be entered 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
ADC
button.
The programmable high-pass filter should now be correctly programmed and enabled. The ADC can now
be enabled with the high-pass filter.
Figure 16. ADC High Pass Filters
4.8.1.2
Digital Effects Filter - ADC
The ADC digital outputs stream can be routed through the digital effects filter in the codec to allow custom
audio 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
4.8.2
DAC Filters
The
DAC Filters
tab is shown in
. Detailed information about the different configuration options
for the DAC filters is discussed in the following sections.
Figure 17. DAC Filters
