Using the AT85DVK-07 Board
2-16
AT85DVK-07 Development Board User Guide
4391B–MP3–07/07
Figure 2-15.
Audio Input Unit Implementation
2.9
Audio Output
Unit
The Audio Output unit consists in 2 stereo 3.5 mm jacks J7 & J8 allowing output selec-
tion between on-chip audio codec (with its optional on-board headphone amplifier) and
on-board audio DAC. Moreover 2 extension connectors J5 and J9 (see Table 2-15 and
Table 2-16) allow user to plug daughter boards replacing on-board headphone amplifier
or on-board audio DAC. In this case, solder straps SE1, SE2, SE19, SE18, SE51 for
external headphone amplifier and SE49, SE50 for external audio DAC must be left
opened to avoid short circuits.
Note:
On-board DAC and on-chip DAC (audio codec) usage is exclusive. User’s selection can
be configured in the audio firmware driver (for further information, refer to the firmware
user’s manual).
Figure 2-16.
Audio Output Unit Implementation
Table 2-15.
Headphone Amplifier Extension Connector (J5)
J3
MIC
Pin Number
Pin Name
Pin Description
1
LVDD
Very Low Voltage VDD power supply 1.8V
2
AMP_EN
Active low amplifier enable signal
3
AMP_IR
Amplifier left channel analog input
4
AMP_IC
Common reference analog input
5
AMP_IL
Amplifier right channel analog input
6
AMP_OR
Amplifier left channel output
J9
J8
J7
J5
