STAC9750 Datasheet, PDF (31/73 Pages) Integrated Device Technology – VALUE-LINE TWO-CHANNEL AC’97 CODECS

STAC9750/9751
VALUE-LINE TWO-CHANNEL AC’97 CODECS
PC AUDIO
6. STAC9750/9751 MIXER
The STAC9750/9751 includes analog and digital mixers for maximum flexibility. The analog mixer is
designed to the AC'97 specification to manage the playback and record of all digital and analog
audio sources in the PC environment. The analog mixer also includes several extensions of the
AC’97 specification to support “all analog record” capability as well as “POP BYPASS” mode for all
digital playback. The analog sources include:
• System Audio: digital PCM input and output for business, games and multimedia
• CD/DVD: analog CD/DVD-ROM audio with internal connections to CODEC mixer
• Mono microphone: choice of desktop microphone, with programmable boost and gain
• Speakerphone: use of system microphone and speakers for telephone, DSVD, and video con-
ferencing
• Video: TV tuner or video capture card with internal connections to CODEC mixer
• AUX/synth: analog FM or wavetable synthesizer, or other internal source
The digital mixer includes inputs for the PCM DAC and the recorded ADC output
Figure 17. STAC9750 2-Channel Mixer Functional Diagram
PCMOut
28h: D5-D4
Slot
Select
2Ah:D5-D4
Slot
Select
6Ah:D1
PCM to
SPDIF
SPDIF
KEY
MonoAnalog
StereoAnalog
Digital
DAC
PC_BEEP
Analog
Audio
Sources
Phone
20h:D8
MIC1
MIC2
LINEIN
0Eh:D6
20 or
30 dB
6E:D2
CD
AUX
VIDEO
ADCRecord
18h
vol mute
0Ah _{vol mute}
0Ch _{vol mute}
0Eh _{vol mute}
10h _{vol mute}
12h _{vol mute}
16h _{vol mute}
14h _{vol mute}
Σ
Σ
AllAnalog
vs
AllRecord
MUX
6Eh:D12
-6dB
Σ
04h
Headphone
Volume
3D
HP_OUT
20h:D15
-6dB
02h
Master
Volume
3D
06h
Σ
Mono
Volume
1Ah
20h:D9
1Ch
3D
Record
Volume ADC
LINE_OUT
MONO_OUT
Slot
Select ^PCMIn
Ganged3DControl
20h:D13
22h:D2-D3
IDT™
VALUE-LINE TWO-CHANNEL AC’97 CODECS
31
STAC9750/9751
V 5.8 103106