STAC9750 Datasheet, PDF (63/73 Pages) Integrated Device Technology – VALUE-LINE TWO-CHANNEL AC’97 CODECS

STAC9750/9751
VALUE-LINE TWO-CHANNEL AC’97 CODECS
PC AUDIO
10.2. Analog I/O
These signals connect the STAC9750/9751 to analog sources and sinks, including microphones and
speakers.
Table 44. Analog Connection Signals
Pin Name
PC-BEEP
PHONE
AUX_L
AUX_R
VIDEO_L
VIDEO_R
CD_L
CD_GND
CD_R
MIC1
MIC2
LINE_IN_L
LINE_IN_R
LINE_OUT_L
LINE_OUT_R
MONO_OUT
HP_OUT_L
HP_COMM
HP_OUT_R
Pin # Type
Description
12 I* PC Speaker beep pass-through
13 I* From telephony subsystem speakerphone (or DLP - Down Line Phone)
14 I* Aux Left Channel
15 I* Aux Right Channel
16 I* Video Audio Left Channel
17 I* Video Audio Right Channel
18 I* CD Audio Left Channel
19
I* CD Audio analog signal return ^†
20 I* CD Audio Right Channel
21 I* Desktop Microphone Input
22 I* Second Microphone Input
23 I* Line In Left Channel
24 I* Line In Right Channel
35 O Line Out Left Channel
36 O Line Out Right Channel
37 O To telephony subsystem speakerphone (or DLP - Down Line Phone)
39 O Headphone Out Left Channel
40 O Headphone Ground Return
41 O Headphone Out Right Channel
* any unused input pins should be tied together through a capacitor (0.1 µF suggested) to ground,
except the MIC inputs which should have their own capacitor to ground if not used.
†_{The CD_GND signal is an AC signal return for the two CD input channels. It is normally biased at}
about 2.5 V. The name of the pin in the AC’97 specification is CD_GND, and this has confused many
designers. It should not have any DC path to GND. Connecting the CD_GND signal directly to
ground will change the internal bias of the entire CODEC, and cause significant distortion. If there is
no analog CD input, then this pin can be No-Connect
IDT™
VALUE-LINE TWO-CHANNEL AC’97 CODECS
63
STAC9750/9751
V 5.8 103106