STAC9708 Datasheet, PDF (51/56 Pages) List of Unclassifed Manufacturers – Multi-Channel AC97 Codec With Multi-Codec Option

SigmaTel, Inc.
Preliminary
STAC9708/11
Appendix A
SPLIT INDEPENDENT POWER SUPPLY OPERATION
In PC applications, one power supply input to the STAC9708/11 may be derived from a supply regulator (as
shown in Figure 3) and the other directly from the PCI power supply bus. When power is applied to the PC, the
regulated supply input to the IC will be applied some time delay after the PCI power supply. Without proper on-
chip partitioning of the analog and digital circuitry, some manufacturer's codecs would be subject to on-chip SCR
type latch-up.
SigmaTel’s STAC9708/11 specifically allows power-up sequencing delays between the analog (AVddx) and
digital (VDddx) supply pins. These two power supplies can power-up independently and at different rates with
no adverse effects to the codec. The IC is designed with independent analog and digital circuitry that prevents
on-chip SCR type latch-up.
3.3V or 5V ± 5%
REG
0.1uF
1uF
* AVdd must always be >= DVdd
0.1uF
0.1uF
10uF
3.3V or 5V ± 5%
0.1uF
25
AVdd1
38
AVdd2
12
PC ^_B E E P
1
DVdd1
9
DVdd2
2
XTL_IN
33pF
24.576MHz
13
PHONE
14
AUX_L
15
AUX_R
16
VIDEO_L
17
VIDEO_R
18
CD_L
S igm a T e l
STAC9708/11
XTL_OUT ₃
SDATA_OUT
5
6
BIT_CLK
8
SDATA_IN
10
SYNC
11
RESET
45
CID0
46
CID1
33pF
19
CD_GND
20
CD_R
21
MIC1
22
MIC2
23
LINE_IN_L
24
LINE_IN_R
45
CID0
46
CID1
27
Vref
28
Vrefout
32
CAP2
31
CAP1
33
CAP3
34
APOP
47
EAPD
35
LINE_OUT_L
0.1uF
10uF
10uF
10uF
22uF
0.1uF
560 - 1000pF
29
560 - 1000pF
30
AFILT1
AFILT2
AVss1
36
LINE_OUT_R
37
MONO_OUT
AVss2 DVss1 DVss2 DAC_OUT_L
DAC_OUT_R
26
NOTE: Pins 31, 33, 34, 40
43, 44, and 48 are No Connects
42 4
7
39
41
** Teminate ground
plane as close to power
supply as possible
Brd Analog Gnd
Brd Digital Gnd
51
10/02/98