SigmaTel, Inc.
Data Sheet
STAC9721
1.2 Analog I/O
These signals connect the STAC9721/23 to analog sources and sinks, including microphones and
speakers.
. Analog Signal List
Table 4
Signal Name
Type
Description
PC Speaker beep pass-through
PC-BEEP
PHONE
I
I
From telephony subsystem speakerphone (or DLP - Down
Line Phone)
MIC1
MIC2
I
I
Desktop Microphone Input
Second Microphone Input
Line In Left Channel
LINE-IN-L
LINE-IN-R
CD-L
I
I
Line In Right Channel
CD Audio Left Channel
CD Audio analog ground
CD Audio Right Channel
Video Audio Left Channel
Video Audio Right Channel
Aux Left Channel
I
CD-GND
CD-R
I
I
VIDEO-L
VIDEO-R
AUX-L
I
I
I
AUX-R
I
Aux Right Channel
LINE-OUT-L
LINE-OUT-R
MONO-OUT
O
O
O
Line Out Left Channel
Line Out Right Channel
To telephony subsystem speakerphone (or DLP – Down
Line Phone)
LNLVL_OUT_
L
O
O
True Line Level Out Left Channel
LNLVL_OUT_
R
True Line Level Out Right Channel
* Note: any unused input pins should be tied together and connected to ground with a capacitor (0.1 uF
suggested), except the MIC1 and MIC2 inputs which require their own 0.1 uF capacitors to ground if not
used.
8
04/07/00
04/07/00
ETC [ ETC ]
