Texas Instruments TLV320DAC26EVM, Руководство пользователя

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Program Description
3-14
Figure 3−4. DAC Output Filter Screen
Different filter coefficients can be loaded for left and right channels, though
usually these are set the same. Six preconfigured filters are selectable using
the drop-down list box of this screen. Selecting one of these updates the
coefficients and causes the graph of the filter response to update. However,
nothing is loaded into the DAC26 until the Download button is pressed.
If changes are made to coefficient values directly, the response can be viewed
on the graph by pressing the View Response button. It is recommended that
you view the response before downloading values to the DAC26, as some
values can cause clipping or oscillation of the filter. The filter equation is
described in the DAC26 data sheet.
Checking the Boost Filter On box enables the filter.
The DAC26 provides another digital filter, the de-emphasis filter, for the audio
DAC. Checking the Deemphasis Filter On box enables the filter.
Moreover, to reduce the DAC26’s power-up pop noise, two pop-reduction
functions were added to the DAC26 and are selectable on this screen. They
are the audio output driver pop-reduction and the audio DAC pop-reduction.
See the DAC26 data sheet for the details of the pop-reduction features.