Texas Instruments TLV320AIC26EVM, User Manual

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Program Description
3-18
Figure 3−7. Audio Screen With AGC On
3.5.3.3 DAC Section
Like the ADC section, the AIC26 audio DAC can be powered on or off. By
default, the DAC is powered off. Before a DAC power on, make sure to check
the DAC output mode on the EVM board. If the audio output is connected to
J6 or J13, the virtual GND should be powered up before the DAC powers up.
Otherwise, if the audio output is connected to J7 ( AC coupled plug), the virtual
GND should be powered down before power up.
The stereo audio volumes can be controlled by the left (L) and right (R) volume
control slides, in three different ways, selectable through setting the master
volume controller: 1) independent, 2) right channel controlled, or 3) left
channel controlled.
Like the audio ADC’s gain controls the DAC’s PGA gain can be changed in soft
stepping either 0.5-dB per one sample, or 0.5-dB per 2 samples.
The audio DACs output swing range can be set from the list in the Output
Peak-to-Peak Range pulldown. Refer to the AIC26 data sheet to find out the
range. Note that the output peak-to-peak range is related to the analog driver
power supply voltage.