Pin Description (Continued)
Analog I/O (Continued)
Name
Pin
I / O
Functional Description
AUX_R
15
I
This line level input can be routed through the Input Mux and recorded by the right ADC. In
addition, this analog input gets summed into the right output stream. The amount of AUX_R
signal mixed in the right output stream can be adjusted from +12dB to 34.5dB in 1.5dB
steps as well as muted via register 16h.
VIDEO_L
16
I
This line level input can be routed through the Input Mux and recorded by the left ADC. In
addition, this analog input gets summed into the left output stream. The amount of VIDEO_L
signal mixed in the left output stream can be adjusted from +12dB to 34.5dB in 1.5dB steps
as well as muted via register 14h.
VIDEO_R
17
I
This line level input can be routed through the Input Mux and recorded by the right ADC. In
addition, this analog input gets summed into the right output stream. The amount of
VIDEO_R signal mixed in the right output stream can be adjusted from +12dB to 34.5dB in
1.5dB steps as well as muted via register 14h.
CD_L
18
I
This line level input can be routed through the Input Mux and recorded by the left ADC. In
addition, this analog input gets summed into the left output stream. The amount of CD_L
signal mixed in the left output stream can be adjusted from +12dB to 34.5dB in 1.5dB steps
as well as muted via register 12h.
CD_GND
19
I
This input can be used to reject common mode signals on the CD_L and CD_R inputs.
CD_GND is an AC ground point and not a DC ground point. This input must be AC-coupled
to the source signal’s ground.
CD_R
20
I
This line level input can be routed through the Input Mux and recorded by the right ADC. In
addition, this analog input gets summed into the right output stream. The amount of CD_R
signal mixed in the right output stream can be adjusted from +12dB to 34.5dB in 1.5dB
steps as well as muted via register 12h.
MIC1
21
I
Either MIC1 or MIC2 can be selected via software and routed through the Input Mux for
recording. The 20dB boost circuit is enabled/disabled via register 0Eh. Also, the amount of
mic signal mixed in the output stream can be adjusted from +12dB to 34.5dB in 1.5dB
steps as well as muted via register 0Eh.
MIC2
22
I
Either MIC1 or MIC2 can be selected via software and routed through the Input Mux for
recording. The 20dB boost circuit is enabled/disabled via register 0Eh. Also, the amount of
mic signal mixed in the output stream can be adjusted from +12dB to 34.5dB in 1.5dB
steps as well as muted via register 0Eh.
LINE_IN_L
23
I
This line level input can be routed through the Input Mux and recorded by the left ADC. In
addition, this analog input gets summed into the left output stream. The amount of
LINE_IN_L signal mixed in the left output stream can be adjusted from +12dB to 34.5dB in
1.5dB steps as well as muted via register 10h.
LINE_IN_R
24
I
This line level input can be routed through the Input Mux and recorded by the right ADC. In
addition, this analog input gets summed into the right output stream. The amount of
LINE_IN_R signal mixed in the right output stream can be adjusted from +12dB to 34.5dB
in 1.5dB steps as well as muted via register 10h.
LINE_OUT_L
35
O
This is a post-mixed output for the left audio channel. The level of this output can be
adjusted from 0dB to 45dB in 1.5dB steps as well as muted via register 02h.
LINE_OUT_R
36
O
This is a post-mixed output for the right audio channel. The level of this output can be
adjusted from 0dB to 45dB in 1.5dB steps as well as muted via register 02h.
MONO_OUT
37
O
This line level output is either the post-mixed output or the mic input. The level of this output
can be adjusted from 0dB to 45dB in 1.5dB steps as well as muted via register 06h.
LNLVL_OUT_L
39
O
This is a post-mixed output for the left audio channel. The level of this output can be
adjusted from 0dB to 45dB in 1.5dB steps as well as muted via register 04h.
LNLVL_OUT_R
41
O
This is a post-mixed output for the right audio channel. The level of this output can be
adjusted from 0dB to 45dB in 1.5dB steps as well as muted via register 04h.
LM4548
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