DATA SHEET
SigmaTel, Inc.
Integrating Mixed-Signal Solutions
STAC9721/23
Stereo AC'97 Codec
With Multi-Codec Option
GENERAL DESCRIPTION:
SigmaTel’s
STAC9721/23
is a general-purpose 18-bit stereo, full duplex, audio codec that conforms to
the analog component specification of AC'97 (Audio Codec 97 Component Specification Rev. 2.1). The
STAC9721/23
incorporates
SigmaTel’s
proprietary Sigma-Delta technology to achieve a DAC SNR in
excess of 95dB. The DACs, ADCs, and mixer are integrated with analog I/Os, which include four analog
line-level stereo inputs, two analog line-level mono inputs, two stereo outputs, and one mono output
channel. Also included are
SigmaTel’s
3D stereo enhancement (SS3D), and an extra true line-level out
for headphones or speaker amplifiers. The
STAC9721/23
may be used as a secondary codec, with the
STAC9700/04/07/44/45
or a 4-channel
STAC9708
as the primary, in multiple codec configurations
conforming to the AC'97 Rev. 2.1 specification. This configuration can provide up to six-channel output,
providing AC-3 playback for DVD applications. The
STAC9721/23
communicates via the five-wire AC-
Link interface with any AC-Link capable controller or advanced core logic chip-set. Packaged in an
AC'97 compliant 48-pin TQFP, the
STAC9721/23
can be placed on motherboards, daughter boards, add-
on cards or AMR/MDC cards.
FEATURES:
•
•
•
•
•
•
•
High performance
Σ∆
technology
Energy saving power down modes
18-bit full duplex stereo ADC, DACs
AC-Link protocol compliance
3.3V Multiple power supply options
Pin compatible with the STAC9700/44/45
SigmaTel Surround (SS3D) Stereo Enhancement
•
•
•
•
•
•
EAPD –
External Amplifier Power Down Control
Multi-Codec option (Intel AC'97 rev 2.1)
Six analog line-level inputs
48-pin TQFP
LINE-to-LINE SNR 102dB
The STAC9723 is tested at +3.3V
ORDERING INFORMATION:
PART
NUMBER
STAC9721T
STAC9723T
PACKAGE
48-pin TQFP 7mm x7mm x 1.4mm
48-pin TQFP 7mmx7mm x 1.4mm
TEMPERATURE
RANGE
0o C to +70o C
0o C to +70o C
SUPPLY RANGE
DVdd = 3.3V or 5V, AVdd = 5V
DVdd = 3.3V, AVdd = 3.3V
SigmaTel reserves the right to change specifications without notice
1
04/07/00
SigmaTel, Inc.
Table of Contents
Data Sheet
9.6
9.7
10.1
10.2
10.3
10.4
10.5
10.6
STAC9721
AC-L
INK
L
OW
P
OWER
M
ODE
36
ATE T
EST
M
ODE
M
AXIMUM
R
ATINGS
:
P
OWER
C
ONSUMPTION
AC-L
INK
S
TATIC
D
IGITAL
STAC9721 A
NALOG
STAC9723 A
NALOG
37
38
39
41
41
43
GENERAL DESCRIPTION:.........................1
TABLE OF CONTENTS................................2
TABLE OF CONTENTS – FIGURES ..........3
1.
PIN/SIGNAL DESCRIPTIONS .............7
10. ELECTRICAL SPECIFICATIONS: ...38
R
ECOMMENDED
C
ONDITIONS
38
1.1
1.2
1.3
1.4
2.
D
IGITAL
I/O
A
NALOG
I/O
F
ILTER
/R
EFERENCES
/GPIO
7
8
9
P
OWER AND
G
ROUND
S
IGNALS
9
C
LOCKING
R
ESET
AC-L
INK
S
ERIAL
I
NTERFACE
10
10
AC-LINK ................................................10
APPENDIX A ................................................45
APPENDIX B ................................................46
2.1
2.2
3.
DIGITAL INTERFACE........................11
TABLE of Tables
Table 1. Package Dimensions
Table 2. Pin Designation
Table 3. Digital Signal List
Table 4. Analog Signal List
Table 5. Filtering and Voltage References
Table 6. Mixer Functional Connections
Table 7. Programming Registers
Table 8. Play Master Volume Register
Table 9. PC_BEEP Register
Table 10. Analog Mixer Input Gain Register
Table 11. Record Select Control Registers
Table 13. Record Gain Registers
Table 14. General Purpose Register
Table 15. 3D Control Registers
not defined.
Table 16. Powerdown Status Registers
Table 17. Extended Audio ID Functions
Table 19: Analog Current Adjust
Table 16. Multi-Channel Programming
Table 18. Low Power Modes
Table 19. Codec ID Selection
Table 20. Secondary Codec Register Access
2
3.1
3.2
4.
11
4
4
7
8
9
20
21
22
22
23
23
24
24
Error! Bookmark
25
26
27
28
29
31
32
AC-L
INK
L
OW
P
OWER
M
ODE
18
M
IXER
I
NPUT
M
IXER
O
UTPUT
PC B
EEP
I
MPLEMENTATION
P
ROGRAMMING
R
EGISTERS
:
20
20
20
21
STAC9721/23 MIXER ...........................19
4.1
4.2
4.3
4.4
5.
6.
LOW POWER MODES ........................29
MULTIPLE CODEC SUPPORT .........31
6.1
6.2
7.
8.
P
RIMARY
/S
ECONDARY
C
ODEC
31
S
ECONDARY
C
ODEC
A
CCESS
32
Table 12. Left Record Select Control Registers 23
TESTABILITY ......................................32
EXTENDED FUNCTIONALITY ........33
8.1
9.
A
NTI
-P
OP
C
IRCUITRY
C
OLD
R
ESET
W
ARM
R
ESET
C
LOCKS
D
ATA
S
ETUP AND
H
OLD
S
IGNAL
R
ISE AND
F
ALL
33
33
34
34
35
35
AC TIMING CHARACTERISTICS .33
9.1
9.2
9.3
9.4
9.5
04/07/00
04/07/00
SigmaTel, Inc.
Table 21. Cold Reset
Table 22. Warm Reset
Table 23. Clocks
Table 24. Data Setup and Hold
Table 25. Signal Rise and Fall Times
Data Sheet
33
34
34
35
35
36
37
38
STAC9721
Figure 2. STAC9721/23 Block Diagram............... 5
Figure 3. AC-Link to its companion controller .. 10
Figure 4. Bi-directional Audio Frame ................. 12
Figure 5. AC-Link Audio Output Frame .......... 12
Figure 6. Start of an Audio Output Frame ....... 13
Figure 7. STAC9721/23 Audio Input Frame ..... 16
Figure 8. Start of an Audio Input Frame ........... 16
Figure 9. STAC9721/23 Powerdown Timing ..... 18
Figure 10. STAC9721/23 Mixer ......................... 19
Figure 11. Powerdown/Powerup flow.................. 29
Figure 12. Powerdown/Powerup flow ................. 30
Figure 13. Cold Reset........................................... 33
Figure 14. Warm Reset ........................................ 34
Figure 15. Clocks.................................................. 34
Figure 16. Data Setup and Hold.......................... 35
Figure 17. Signal Rise and Fall Times ................ 35
Figure 18. AC-Link Low Power Mode Timing.. 36
Figure 19. ATE Test Mode .................................. 37
Table 26. AC-Link Low Power Mode Timing
Table 27. ATE Test Mode
Table 28. Operating Conditions
Table 33: Power Consumption 39
Table 34: Power Consumption at 3.3V Analog 39
Table 35: Reduced Analog Power Settings
Table 30. AC-Link Static Specifications
40
41
Table 31. Analog Performance Characteristics 41
Table 32. Analog Performance Characteristics 43
Table of Contents – Figures
Figure 1. Package Outline ..................................... 4
3
04/07/00
04/07/00
SigmaTel, Inc.
Figure 1
. Package Outline
D
D1
26
38
Data Sheet
STAC9721
Table 1
. Package Dimensions
Key
TQFP Dimensions
9.00 mm
7.00 mm
9.00 mm
7.00 mm
0.20 mm
0.50 mm
1.4 mm
a
e
SigmaTel
E
E1
48 pin TQFP
14
2
D
D1
E
E1
a (lead
width)
e (pitch)
thickness
Table 2
. Pin Designation
PIN
#
1
2
3
4
5
6
7
8
9
10
11
12
Signal Name
DVdd1
XTL_IN
XTL_OUT
DVss1
SDATA_OUT
BIT_CLK
DVss2
SDATA_IN
DVdd2
SYNC
RESET#
PC_BEEP
PI
N#
13
14
15
16
17
18
19
20
21
22
23
24
Signal Name
PHONE
AUX_L
AUX_R
VIDEO_L
VIDEO_R
CD_L
CD_GND
CD_R
MIC1
MIC2
LINE_IN_L
LINE_IN_R
PIN
#
25
26
27
28
29
30
31
32
33
34
35
36
Signal Name
AVdd1
AVss1
Vref
Vrefout
AFILT1
AFILT2
CAP1
CAP2
CAP3
APOP
LINE_OUT_L
LINE_OUT_R
PIN
#
37
38
39
40
41
42
43
44
45
46
47
48
Signal Name
MONO_OUT
AVdd2
LNLVL_OUT_L
NC
LNLVL_OUT_R
AVss2
NC
NC
CID0
CID1
EAPD
NC
# denotes active low
4
04/07/00
04/07/00
SigmaTel, Inc.
Data Sheet
4 stereo
sources
2 mono sources
mono
stereo
PCM out DACs
48Kss
STAC9721
Power
Management
LNLVL_OUT
MIXER
Analog mixing
and
Gain control
Mic
Boost
0/20 dB
M
U
X
AC-link
SYNC
BIT_CLK
SDATA_OUT
SDATA_IN
RESET
Digital
Interface
DAC
DAC
LINE_OUT
MONO_OUT
MIC1
MIC2
Registers
64 x 16 bits
PCM in ADCs
ADC
ADC
48Kss
Figure 2
. STAC9721/23 Block Diagram
The
STAC9721/23
block diagram is illustrated above. It performs fixed 48K sample rate D-A & A-D
conversion, mixing, and analog processing. The digital interface communicates with the AC'97 controller
via the five wire AC-Link and contains the 64 word by 16-bit registers. Two, fixed 48Ks/s DAC’s
support two stereo PCM-out channels. The digital mix of all software sources, including the internal
synthesizer and any other digital sources, is performed in the digital controller. The Mixer block mixes
the PCM_OUT with any analog sources, then outputs to LINE_OUT and LNLVL_OUT. The
MONO_OUT delivers either mic only or a mono mix of sources from the mixer. The two fixed 48Ks/s
ADC’s take any mix of mono or stereo sources and convert it to a stereo PCM-in signal. All ADC's and
DAC's operate at 18-bit resolution.
The
STAC9721/23
is designed primarily to support stereo, 2-speaker audio. However, true AC-3
playback can be achieved for 6-speaker applications by taking advantage of the multi-codec option in the
STAC9721/23.
Using this option with a STAC9704/07/21/23 or the 4-channel STAC9708 as the primary
codec, and the STAC9721/23 as the secondary codec, 6-channel output can be achieved in an AC'97
architecture. Also, the
STAC9721/23
provides for a stereo enhancement feature,
SigmaTel Surround 3D
or SS3D. SS3D
provides the listener with several options to expand the soundstage beyond the normal 2-
speaker arrangement.
Together, with the logic component (controller or advanced core logic chip-set) of AC'97, the
STAC9721/23
can be SoundBlaster
and Windows Sound System
compatible. SoundBlaster
is a
registered trademark of Creative Labs. Windows
is a registered trademark of Microsoft Corporation.
5
04/07/00
04/07/00
京公网安备 11010802033920号
EEWORLD
