STAC9751XXTAEC1X IDT, Integrated Device Technology Inc, STAC9751XXTAEC1X Datasheet - Page 33

• Manufacturer Part Number: STAC9751XXTAEC1X
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of STAC9751XXTAEC1X

• Single Supply Voltage (typ): 3.3/5V
• Single Supply Voltage (min): 3.135V
• Single Supply Voltage (max): 3.465/5.25V
• Package Type: TQFP
• Lead Free Status / RoHS Status: Compliant

IDT™
VALUE-LINE TWO-CHANNEL AC’97 CODECS
STAC9750/9751
VALUE-LINE TWO-CHANNEL AC’97 CODECS
6.1.
6.2.
6.3.
6.4.
Analog Mixer Input
Analog Mixer Output
SPDIF Digital Mux
PC Beep Implementation
The mixer provides recording and playback of any audio sources or output mix of all sources. The
STAC9750/9751 supports the following input sources:
•
•
•
The mixer generates three distinct outputs:
•
•
•
The STAC9750/9751 incorporates a digital output that supports SPDIF formats. A multiplexer deter-
mines which of two digital input streams are used for the digital output conversion process. These
two streams include the PCM OUT data from the audio controller and the ADC recorded output. The
normal analog LINE_OUT signal can be converted to the SPDIF formats by using the internal ADC
to record the “MIX” output, which is the combination of all analog and all digital sources. In the case
of digital controllers with support for 4 or more channels, the SPDIF output mode can be used to sup-
port compressed 6-channel output streams for delivery to home theater systems. These can be
routed on alternate AC-Link slots to the SPDIF output, while the standard 2-channel output is deliv-
ered as selected by bits D5 and D4 in Register 6E. If the digital controller supports 6 channels, a
SPDIF output with 4 analog channels can also be configured (in a multi-CODEC setup).
information for SPDIF please see 6.5.12.2; page 44.
Pin 48: To Enable SPDIF, use an 1 KΩ-10 KΩ external pulldown. To Disable SPDIF, use an
1 KΩ-10 KΩ external pullup. Do NOT leave Pin 48 floating.
PC Beep is active on power up and defaults to an un-muted state. The PC_BEEP input is routed
directly to the MONO_OUT, LINE_OUT and HP_OUT pins of the CODEC. Because the PC_BEEP
input drive is often a full scale digital signal, some resistive attenuation of the PC_BEEP input is rec-
ommended to keep the beep tone within reasonable volume levels. The user should mute this input
before using any other mixer input because the PC Beep input can contribute noise to the lineout
during normal operation. This style of PC Beep is related to the AC’97 Specification Rev 2.2. To use
the analog PC Beep, a value of 00h to bits F[7:0](D[12:5]) disables the Digital PC Beep generation.
PV[3:0] (D[4:1]) controls the volume level from 0 to 45dB of attenuation in 3dB steps.
Note: All unused inputs should be tied together connected to ground through a capacitor (0.1
Note: Mono output of stereo mix is attenuated by -6 dB.
Any mono or stereo source
Mono or stereo mix of all sources
Two-channel input with mono output reference (microphone + stereo mix)
A stereo mix of all sources for output to the LINE_OUT and HP_OUT
A stereo mix of all analog sources for recording
Microphone only or mono mix of all sources for MONO_OUT
33
STAC9750/9751
µ
F suggested).
PC AUDIO
V 5.8 103106
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